KOISE
FA
U. S. ENVIRONMENTAL PROTECTION
    AGENCY
 WASHINGTON, D. C. 20450

-------
         NOISE FACTS DIGEST
              June 1972
               for the

 US BWJra*MB*TAL PROTECT ION AGENCY
OFFICE OF NOISE ABATEMENT AM) CONTROL
        WASHINGTON, DC 20460
                 by

          INFORMATICS INC.
                under
         CONTRACT 68-01-0512

-------
                        INTRODUCTION







          This pilot issue of Noise Facts Digest has been



prepared in response to a widely expressed need for more and



better information on the prevention,  abatement and control of



noise.







          It contains two general-interest articles as well as



about two hundred abstracts of material  selected from the most



recent and significant of the domestic and foreign literature.



These abstracts are designed to provide substantive informa-



tion.  Publications which have been judged difficult to obtain or



use have been abstracted at greater length than those judged



easy to obtain.  All abstracts are supported by detailed biblio-



graphic data in order to enable the  reader to obtain the  source



document directly.  We would be pleased to assist you whenever



a source document is difficult to  obtain.   Material was selected



for abstracting on the basis of its potential interest to a wide



range of readers including not only specialists in noise  abate-



ment and control,  but also state and local officials, planners,



builders, highway engineers and  all those who are only



peripherally concerned with noise.

-------
          Although the Digest concentrates on factual



information,  we have widened its  scope to include opinions and



recommendations presented at the EPA Hearings on noise held



last year.  These witness statements provide the reader with an



opportunity to obtain an impression of the problem of noise  in



America as seen from many different viewpoints.








          This issue presents  the  sub-topics of noise compre-



hensively.  Possible future issues might be dedicated to one or



two special topics.   We are actively seeking the reader's com-



ments  and  suggestions.  Please fill out  and return the User



Response Form as  soon as  you have finished perusing this



issue.   Thank you for your  cooperation.
                                11

-------
                       TABLE OF CONTENTS
1NTRODUCTI ON
FEATURES
          Chicago's New Noise Ordinance-
          The First Year                                              1

          New Noise Information Retrieval  System Now  on  Line          15
ABSTRACTS

          EPA Hearings                                               17

          Noise Subject Field and Scope Notes                        42


INDEXES

          Subject Index (BLUE)                                      147

          Author Index (BLUE)                                       164

          Glossary,  Abbreviations,  Acronyms  (YELLOW)                 168

          List of Sources (WHITE)                                   197

-------
        CHICAGO'S NEW NOISE ORDINANCE - THE FIRST YEAR

          Almost a year has passed since the 1971 Chicago Noise Ordi-
nance went into effect,  and it is now possible to assess its preliminary
impact.  There have been two basic reactions noted.  The first is the
great interest shown by other communities in the Chicago ordinance.
Among the hundreds of inquiries received by the Chicago Department of
Environmental Control have been many from other towns and cities seeking
to develop their own anti-noise legislation or implement noise control pro-
grams.  Indeed,  the noise ordinance recently passed (June 1972) by the city
of Baltimore is modeled closely on the Chicago legislation.

          The second,  and more immediate, reaction to the Chicago law
has been a dramatic increase in the number of noise complaints from
Chicago's citizens,  (See Figure 1.)  In 1970 the city government received
approximately  120 noise complaints.  During the first six months of 1971
             1500 - -
              1000 -i -
    Noise
    Per Six
    Month
    Period
               500--
                    1970
           FIGURE 1.  INCREASE IN NOISE COMPJLA1NTS IN
                         THfi CITY OF CHICAGO

-------
(before the new law went into effect) the number of complaints rose to
approximately 220.  The big increase came in the last half of 1971 "when
noise complaints climbed to over 1, 300--or almost 40% of all the com-
plaints  received by the Department of Environmental Control.  This
percentage decreased to around 20% of all  complaints during  the winter
months, reflecting the prevalence of closed windows and the improved
noise reduction afforded by them.

          The significance of these statistics (especially the  almost 1,500%
increase in complaints over the 1970 base  period) is  three-fold.  First,
they reflect the new stringency of the noise ordinance.  Second,  they
indicate an expanded public awareness of noise as an environmental pollutant.
Third,  and, perhaps,  most significantly,  they can be directly related to the
well-publicized inauguration of the ordinance and  the existence  of a single,
known,  place  to which complaints can be addressed.

          Other communities planning to establish an office of noise  control
can look forward to  a similar increase in complaints if they,  like Chicago,
properly publicize their noise-abatement activities.

          Table 1 shows a breakdown of noise complaints by  noise  source.
Relatively more complaints came from  affluent neighborhoods than from
poorer  ones.

          The remainder of this article will focus on the insights that have
emerged from Chicago's first year of experience--insights that may be of
great interest to other cities.  The reader is also referred to two abstracts*
on the Chicago experience in the abstract section  of the Digest.
   No.  08-011, and No. 08-012.

-------
                                TABLE  1
              COMPLAINT SUMMARY AND BREAKDOWN
                                 FROM
                    JULY1, 1971 to MARCH 1,  1972
CATEGORIES                                    INVESTIGATIONS MADE
Ice Cream Trucks                                           13
Buses                                                       3
Trucks                                                    125
Motorcycles                                                82
Automobiles                                                80
Air Conditioners                                           190
Exhaust Fans                                               97
Chicago Transit Authority                                   23
Construction                                               151
Hornblowing                                                77
Scavengers (privately operated refuse trucks)               142
Musical Instruments                                       109
Miscellaneous Noises                                      214
Gas Stations                                                34
Factory Noises                                             113
Lawn Mowers                                                2
Loudspeakers                                               95
Doorman Whistles                                           11
Car Washes                                                 9
Church Bells                                                25
Vibrations                                                  55
Refrigeration Units  (Trucks)                                  8
Dust Collectors                                              3
Burglar Alarms                                              7
Airplanes                                                    4

(Subtotal)                                                 1,685

Railroad Noise                                              60

Total                                                    1,745
Chicago's New Standards


          Chicago's present ordinance is the result of new legislation super-

imposed on an older (1957) noise code.  The previous code contained a zoning

approach,  with limits  placed on noise levels at the boundaries separating

various use zones—from heavy manufacturing to residential.  It also con-

tained nuisance provisions which served as "catch-alls" for the many unusual

noise sources which exist in a city.  These have been retained and modified.

For example,  Table 2  shows limits on noise from buildings and installations.

-------
          Cosimo Caccavari, Supervisor of the Noise and Vibration Control
Office,  makes a point of particular interest to owners and operators of
factories and buildings with noisy equipment.  Sometimes a new source  is

turned on that produces noise at the lot boundaries  10-15 dB higher than the
previous background.   If complaints  started (and most likely, they would),

continued operation would be likely to mobilize opposition to the point where

practically no amount of subsequent noise reduction would satisfactorily reduce
the stream of complaints.
                                TABLE 2
       LIMITS ON NOISE FROM BUILDINGS AND INSTALLATIONS
Type of District
                  |          Limits
Where Measured  j (For Monitoring Purposes)
Business  & commerical
districts
At boundaries
of the lot
62 dBA
Residential
At boundaries
of the lot
55
Vlanufacturing
   --Restricted
     Manufacturing
     -General
     Manufac turing
     -Heavy
     Manufac turing
At zoning district
boundaries
                  55   On boundary with a
                       residential district

                  62   On boundary with a
                       business-commercial district

                  58   On boundary with a
                       residential district

                  64   On boundary with a
                       business commerical district

                  61   On boundary •with a
                       residential district

                  66   On boundary with a
                       business-commercial district
          A new provision of the ordinance requires that manufacturers and

vendors certify that new equipment on sale in Chicago, including vehicles,

-------
meet noise limits.  These limits will become stricter on equipment manu-

factured after certain dates in the future.  Limits on present manufactures

are shown in Table 3.
                               TABLE 3
             NOISE LIMITS NOW IN EFFECT ON NEWLY-
           MANUFACTURED EQUIPMENT SOLD IN CHICAGO
Motorcycles

Trucks (over 8000 Ibs. gross weight)

Cars  & other vehicles

Construction & industrial equipment, including
bulldozers,  drills,  loaders, power shovels,
cranes, derricks, motor graders, paving
machines,  off-highway trucks, ditchers,
trenchers, compactors, scrapers, wagons,
pavement breakers, compressors, and
pneumatic equipment--pile  drivers not
included.

Equipment of less than 20 hp for occasional
use in residential areas,  including chain saws
pavement breakers, log chippers, powered
hand tools,  and the like.

Equipment for repeated use in residential
areas such as lawnmowers,  small lawn &
garden tools,  riding tractors,  &: snow
removal equipment.

Snowmobiles

Dune  buggies, all terrain vehicles, go-carts,
mini bikes.
                                                    Noise Limit in dBA,
                                                    Measured at 50 Ft.
                                                         dBA
                                                     88
                                                     94
                                                     74
                                                     82
          The main thrust of the new ordinance is directed at motor vehicles

and other types of noisy equipment.  Thus, the heart of Chicago's noise con-
trol program consists of vigorous enforcement of the older regulations when
a ci.mt:1 lint is made, plus active enforcement of the new operational limits on
motor vehicles.

-------
          Operational limits cm vehicle noise mow in effect .axe measured
at a. distance of 50 feet.  They are Eg dBA for trades (or 90 dBA at speeds
over 35 mph),  82 dBA. for motorcycles ($6 dBA at speeds over 35 aaaph},  amd
76 dBA for passenger cars J82 dBA at speeds over 35 mph).  Tine limit on
trucks is on total emission including noise from auxiliary equipment such
as refrigeration units.   These limits will be ™a«jk» progressively stricter in
the future.  (Details on these future limits are given in abstract No. 08-Oil
also in this issue).  So far, the over-35 mph limits have not been
enforced, in order to eliminate a variable,  tire noise,  that might be used by
defendents as an excuse in court.

Program Enforcement

          Here is how tine enforcement program works: Chicago's Depart-
ment of Environmental Control is responsible for all types of pollution
problems, including noise.  Its fingimeerijag Division and Enforcement
Division cooperate on carrying oat the noise control program.  The Enforce-
ment Division has 35 Environmental Control squad cars, radio dispatched,
on the streets on the streets 24 hours a day, seven days a week.  Tfoese cars
must respond to all environmental complaints concexniiag air, water, and
solid "waste, as well as noise.  Seven inspectors with special responsibility
for noise Tide the squad cars.  The members of the Emvorcememl Division
•write citations for all violations except those involving moving vehicles,
"where cooperation of the Chicago Police Department is needed to curb a.
vehicle.  Thus, there are two special vehicle enforcement teams which set
up at preselected sites aroumd the city to apprehend violators.  The sites
have been selected by fhp Engineering Division to  meet SAE  measurement
specification; they must afford a free and clear area within a. 1OO foot radius
of the microphone of the noise meter. This condition is hard to meet in an
urban area, axed the Engineering Division had to search hard  for eraoogrh
suitable sites.  A Chicago police officer, is detailed specifically to -work
with the measurement team. He stands by in a -waiting Environmental Control
squad  car and is alerted by radio to curb "flue violator and to issue the citation.
To be sure  that they have good court evidence, flue measurement team re-
checks the calibration of the sound level meter immediately after leggiiag the
meter reading.

-------
           Tiber* is a complicatiag factor, namely, the question of who
gets the ticket.  When a truck is cited,  the issue is,  what is more
responsible for due noise, tixe condition of the truck oar the way in -which it
-was operated ?  The procedure that has been developed is that the truck
owner usually must post bond to release the  truck and its driver.

           In an eight month period,  1, 026 traffic citations were issued arad
fines of $7,851 were levied.  Tike work of the Enforcement and Engineering
Divisions dovetails.  Every complaint must be responded to,  Enforcement
bandies most of this caseload.  Some complaint, situations are technically
difficult, such as when there  are two or more moise sources 
-------
of steps--from building a simple enclosure to relocating the unit--to help
bring older units into compliance.  A useful procedure for complex violations,
such as noise from manufacturing plants, is the supervisory program with
phased noise reduction.  After being cited, the violator can request a hearing
(there have been79 such hearings in an eight-month period).  The Engineering
Division and the violator discuss the problem and alternative methods of
noise reduction,  and the violator has from two  to four weeks in which to
come up with a proposed noise reduction program.   This program can be
designed in  phases, starting with the simplest and least expensive reduction
methods,  but must lead to compliance within a  fixed period.  The phases
must  be compatible with each other and not  go off  in different directions.
Thus, if "phase one" does not achieve  sufficient reduction,  the violator
knows in advance that he must try the next step, and he knows  in advance
what the next step will be.  If the Engineering Division approves the plan, it
may recommend to the court that the violator's fine be waived  and that he be
put into the supervisory program where his progress will be monitored by
the Engineering Division.  Several dozen cases are  now in the  supervisory
program, and about ten cases have successfully passed through  it and are
now in compliance.

Continuing Study of Noise Parameters

          Within the Engineering Division, the staff specializing in noise
consists of three professionals and three technicians.   The annual operating
costs of the entire noise program are running about $250,000 (or under 10
-------
design stage.  Finally, noise specifications are prepared for inclusion in the
specifications for new equipment purchases by other city agencies.  It can
be seen that adequate engineering backup is no mere luxury for a city noise
control program,  but rather a critical ingredient for its success.

          Such preventative measures, which require the scrutiny of engi-
neers experienced in acoustics,  are an effective method of achieving noise
reduction over the long term at very low cost.   The Department of Environ-
mental Control would like to devote more time to this  activity.

Public Awareness

          One factor of great help to the success of Chicago's program was
the effort made to get enforcement of the new ordinance off to a flying start.
The two basic ingredients were a thorough publicity campaign before the
ordinance went into force, and vigorous enforcement of the ordinance from
the very first day it was in effect.

          Supervisor Caccavari appeared at length on five or six radio  talk
shows  to answer  telephone inquiries.  A 60-second public service spot
announcing the new law, and giving  a telephone number for further informa-
tion, was run frequently by a local TV station.  Day and night telephone
numbers for making complaints  were publicized.  Inexpensive pamphlets
that explained the law in detail were printed (cost: about $500 for 50, 000).
Ten thousand of these pamphlets were  mailed out to local businessmen and
manufacturers and also to selected  manufacturers nationwide.  One hundred
thousand "SSSHHICAGO, " lapel buttons were distributed.

          In the weeks before July 1st, 1972, a complimentary inspection
site was set up which served several purposes: advising motorists who
wanted to learn if their vehicles would be in compliance with the new law,
publicizing the new law, and providing the new noise inspectors with on-the-
job practice.  Several motorcycle groups were among the citizens who turned
up to see how loud they were.  The  cost of various  publicity items totaled less
than $10, 000.  The existence of  a public  relations division within the Depart-
ment of Environmental Control was a great aid in the timing and coordination
of this publicity.

-------
Training the Enforcers

          A training program was set up for noise enforcement personnel.
It featured a one-week course on noise and noise enforcement, complete
with instruction manual, prepared by the Engineering Division of the
Department of Environmental Control.   This course was presented to 45
attendees,  17 of whom were scheduled for noise field testing work with the
Enforcement Division.  Because the new ordinance went into effect in the
summer, when smoke from buildings was less  of a problem, several  air
pollution personnel in the Department could be  transferred to the noise pro-
gram during the first days, thus increasing enforcement impact.

Evaluation
          The Chicago ordinance is, enforceable,  for the most part.  Investi-
gation of some 1800 complaints over an eight-month period revealed about
900 cases where there was a violation, and citations was issued.  Of those
citations processed through the courts,  convictions were obtained in 85-90%
of the cases.

          Since abatement was achieved,  in some cases without, resort to
eitationr., and since most  offenders involved in court cases eventually came
into compliance, it may be concluded that legal processes led to abatement
in most cases.  This contrasts favorably with the  situation in New  York,
where the Bureau of Noise Abatement, which presently has little legal power,
has relied chiefly on persuasion to secure some degree of abatement in about
30% of the complaints  it has handled.

          The most successful part of the Chicago enforcement program to
date has been reducing the amount of horn blowing in the  "Loop" area of the
city.  Horn blowing by taxicabs was a large part,  but not all, of the noise
problem there.  Cooperation came from the city courts in the form of some
clear-cut decisions accompanied by large fines.  The publicity  stemming
from  these  court cases has deterred other potential violaters.
                                     10

-------
           Effectiveness of the ordinance in reducing noise levels must be
evaluated more cautiously.  For one  thing, significant reduction of noise
sources will be observed only after a period of time,  when the progressively
more stringent noise limits on equipment go into effect and the supervisory
programs,  described above, reach successful completion. Presently,
trucking firms find they can usually bring  their vehicles  into compliance by
improving exhaust systems.  Future  limits, especially the 1980 standard of
75 dBA for trucks,  may be more difficult to meet.

           The limitation on sales  seems to entail more enforcement pro-
blems.  When the ordinance first went into effect in July 1971, only 10
manufacturers or vendors had established communication with the Depart-
ment.   There are now  300 on file, although not all of  these have yet filed the
required certification.  Effectiveness of this program is also threatened by
the sale of unregulated products, close to,  but not in  Chicago.

           The outlook for further  limits on noise sources is  complicated by
probable Federal preemption.  The main argument for Federal regulation
of noise sources is that it would eliminate  the possibility of manufacturers
being faced with a "patchwork quilt" of local ordinances differing in measure-
ment techniques as well as numbers.   Chicago agrees that Federal regulations
make sense,  but points out that even after the  legislation giving EPA
authority to set limits is passed it will be  several years  before those limits
can be promulgated and put  into force.  Until then, the local  limits can fill
the gap in  Chicago. Moreover,  experience from the Chicago and California
programs  will provide valuable data on feasibility and enforceability when
Federal standards are drawn up.

           A question as to •whether the City could not do  more about aircraft
noise is appropriate since Chicago owns and operates  three airports.  The
problem is a complicated  one.  Aircraft in the air or landing and taking  off
are under  the jurisdiction of the FAA, and beyond local control.  This still
leaves the noise from ground run-ups, for which the airport  operator  is
responsible.  The Department of Environmental Control  handles this nuisance
like  any other--on a complaint basis.  So far,  there have been few  complaints
(Table 2),  perhaps indicating that noise from ground run-ups is neglibible
compared  to that caused by aircraft in flight.  In one  sense,  aircraft noise
is a secondary problem in Chicago, compared to its impact in communities
                                     11

-------
like Inglewood,  California.  It is estimated that about 15% of Chicago's
population is adversely affected by aircraft liaise, whereas  surface trans-
Doxation noise affects neaxly all residents.

           The noise control program does not yet regulate total noise at
the boundary of construction sites.  Provisions concerning this problem
and also the problem of noise specifications in building codes -were not
included in the 1971 ordinance, because it was felt that additional technical
information was needed. Meanwhile, other measures axe being used for
enforcement.  The limits on sales equipment manwfactared aftex January
1972 is one example, although it only applies to equipment sold in Chicago.
Contractors can be  cited fox disturbing the peace if they operate  equipment
with unrnuffled exhausts.  Construction equipment is pxohibited from
operating -within 600 feet of residential  buildings between 9:30 P, M, and
'8:00 A.M., except for work on public improvements and the work of public
utilities.   Upon request, contractors have changed to quieter equipment and
xe-located noisy equipment.  One  contractor was required to construct a
partial enclosure around a pile driver.

           The private scavenger refuse trucks have been a  difficult problem
so fax. They usually meet the noise emissions limits,  tout since they
operate mostly at night,  their noise is intriusive enough to be annoying.

           Another intractable problem  is noise from the Chicago Transit
Authority (CTA) system, particularly the elevated portions whose noise
annoys the community as well as passengers.  The system can not simply be
shut down,  because thousands of citizens depend on it for transportation.
Yet, costs of completely noise-treating it are prohibitive, although the
gradual introduction of quieter  rolling stock -will lielp.   The new CTA
extensions now being planned will  benefit from noise control features
incorporated in the  design stage,  A private acoustical firm has been hired
to do this work, and the Department of  Environmental Control  is supplying
survey data.

           In a larger sense, the question of effectiveness must ultimately
be defined on the basis  of reduction of urban noise to levels consonant with
health.  As defined by the World Health Organization,  this includes aiot only
the absence of disease, but a positive state of well-being.  Hexe, CMcago1®
                                      12

-------
noise program can provide only part of the solution: unless noise problems
in areas outside of the city's jurisdiction are systematically reduced at the

same time.  These problems include aircraft noise and future urban free-

ways,  for which design criteria are to be issued at the national level.
Finally, the ultimate effectiveness  of the program will depend on the support

and cooperation of the people of Chicago. A large portion of Chicago's

program depends  on the complaint as the point at which investigation and

enforcement are initiated,  so the minimum requirement for the success of

the program is a citizenry concerned enough to pick up the phone -when

necessary. As the statistics show, a successful public awareness compaigni

can do much to foster citizen concern.



         In conclusion,  Chicago's experience suggests several points to be

considered by other cities contemplating noise control programs of their own:


         o    Enforcement in Chicago's main area of emphasis--vehicle
               noise--can be effective, but the true impact of the program
               will not be felt until the more stringent limits scheduled for
               the future go into effect.

         o    Start-up costs cd a noise program are now somewhat
               reduced for other cities, because  preliminary studies
               done by Chicago, Boston,  and several other cities are
               available.  Chicago's preliminary study cost $54,000;
               much of its findings are applicable to the problems of
               other cities.* However, other initial  costs must be
               considered: preliminary noise survey,  purchase of
               measuring instruments 'Chicago's cost $30,000,
               including a mobile measurement van), training costs,
               and hiring an acoustical consultant.

         o    The hearirg process for proposed legislation is crucial.
               It is a good idea to hire an acoustical consultant with
               outstanding credentials to be an expert witness, explain
               technical points, and assist in writing amendments.  Key
               groups who will be affected by the legislation should be
               urged to appear at the hearings.  An effort should be made
               to  canvass members of the industrial community, because
               it is often possible to find industrial spokesmen sympathetic
               to  the legislation who can be asked to testify.
  A copy of this study is available at $15. 00 from the Department of
  Environmental Control,  320 N. Clark Street, Chicago, Illinois  60610.
                                     13

-------
The enforcement staff must have at least some engineering
back-up if the program is to be a success.  It is indispensible
for such duties as measurements in complicated situations,
training others, testimony in court, helping those cited with
violations achieve compliance,  reviewing building plans  to
pinpoint and prevent future noise violations at the  design
stage, and designing  a measurement program to evaluate
program effectiveness,

A noise control program is strengthened when it can draw
on the larger resources of a comprehensive city department
for environmental affairs.

The most important single factor to the success of the
enforcement of a new noise control law is having trained,
practiced enforcement officers ready to begin operations
from  the first day that the new law is in force.
                      14

-------
       NEW NOISE INFORMATION RETRIEVAL SYSTEM NOW ON LINE

          In late June the Environmental Protection Agency launched a new
information system dedicated to noise abatement and control.  It is scheduled
to be fully operational as early as mid-July.   This  system, designed for
future growth, will contain, initially,  approximately  one thousand  citations
and abstracts of various publications.  It has been estimated that,  ultimately,
this  data base may exceed 50, 000 citations.  The abstracts in  this pilot issue
are representative of the information available from  this system.  In fact, if
future issues of this Digest are to be forthcoming,  they will be generated as
a by-product of this information system.

          The data contained in this new system are  directly accessible from
a remote  terminal.  The Office of Noise Abatement and Control anticipates
that  the data base contained in this system  will ultimately be, transferred to an
EPA-wide system which provides for terminal access from over twenty  stations
throughout the United States.  The  capability exists to add further  access
terminals including overseas locations linked through satellite communications.

          For the  time  beinj,, only recent publications are  included in the
data base, i.e.,  publications issued no earlier than 1969.   The bulk of the
coverage  emphasizes current materiel including such items as witness
statements  given at the EPA Noise Hearings, Environmental Impact Statements,
items from the current  periodical publications, proceedings of conferences,
government contractor reports, as well as special locally oriented reports.

          The EPA, in  its Report to Congress, showed that the rest of the
world has developed a wealth of practical information on noise abatement and
control.   Therefore, a particular effort has been made to include,  in English,
the best of this information.

          All abstracts  are  indexed in depth.  The index terms contained in
this publication reflect only  a small fraction  of the terms residing  in the
system.   Thus, it is possible to specify a query at a  very fine  level of detail.
Eventually, a comprehensive thesaurus will be developed which should aid the
user in formulating his  question.
                                       15

-------
          To use the system, full Boolean logic may be applied.  Thus, the
user can connect his search terms with "and", "or", "not," &: "and/or" links.
He can also specify  geographical areas  of interest as well as author, corporate
source and other elements of the bibliographic citation.  A search formulation
might appear as follows:

                 TRUCKS,  or DIESEL  ENGINES, and or
                 MUFFLERS, TRUCK, and (REGULATION,
                 or LEGISLATION),  and  or ENFORCEMENT,
                 not CALIFORNIA

          Such a query should provide informative abstracts on enforcement
of truck noise regulations in states  other than California.  Once this query
has been keyed and a transmit button has been pressed,  the system -will
respond within a few seconds with an indication of the number of "hits, " i. e. ,
the  number of abstracts available against  such a query  formulation.  If the
number of "hits" is  either greater or  smaller than desired,  the query  should
be reformulated until the number of "hits" is approximately equal to that
desired.   A command can then be given which will produce the citations and
abstracts in typed form --or displayed on a cathode  ray tube depending on the
type of terminal utilized.  An alternate  lower  cost response can be  provided
if an over-night batch process is requested in lieu of the conversational mode
response.

          Initially,  this system will facilitate ONAC's responses  to inquiries.
Ultimately,  multiple users will interrogate the system  simultaneously. Other
files, equally accessible, will contain records on on-going research pending
and completed litigation and enforcement experience  as  well as other related
information.
                                       16

-------
                               ABSTRACTS

                             EPA HEARINGS

         The following pages contain abstracts of selected witness statements
at the EPA hearings on the problem of noise pollution.  These public hearings
were conducted in 1970 by the Office of Noise  Abatement and Control in
response to a mandate given by Congress in Title IV of PL-91-604, signed
into law  in December 1970 by President Nixon.   Most of the witnesses ai,
the hearing in a particular city  spoke on a common theme  topic.  The cities
in which the hearings -were held, and the theme topics for  each city,  were
as follows:

         Atlanta, GA        Noise in construction.
         Chicago, IL        Manufacturing and transportation noise .
         Dallas,  TX         Urban planning and noise.
                            Architectural  design and noise.
                            Noise in the home.
         San Francisco, CA Standards,  measurement methods .
                            Legislation and enforcement problems.
         Denver, CO        Agricultural and recreational noise.
         New York,  NY      Transportation,  urban noise and social
                               behavior.
         Boston,  MA        Physiological  and psychological effects.
         Washington, DC    Technology and economics of noise  control.
                            National programs and the relations with state
                               and local programs.

         In the following pages, the abstracts  are arranged by the cities  in
which the hearings were held.

         Full transcripts of all  of the -witness  statements,  published by the
EPA for each hearing,  are available from Supt. of  Documents, U. S. Govern-
ment Printing Office, Washington, D. C. , Zip 20402.  For a list of all witnesses
and their organizations, the reader is  referred to Appendix C  of the Report
to the President and Congress  on Noise (also available from USGPO: SN  5500-
0040,  1972, $1.75).
                                      17

-------
00-001
                                                        HEARINGS
    00-001

    Hasten, J.
    Bergsten, L.

    CaterpiIlar Tractor Company,
    Peoria, I L

    On:  NOISE SUPPRESSION PROGRAM IN THE TRACTOR
         INDUSTRY

    Witness Sfatement
    Public Hearings on ftoise Abatement and Control-

    Atlanta,  !UL 8, T97!
    The problems encountered in attempting to equip
    or modify a tractor to meefr the operator noise
    exposure standards of the Walsh-Hea-ley Act are
    presented.  Over 10,000 engineering design
    hours and 4000 roan-fiours were requ i red to
    produce a single serr of prototype par^s which
    formed a noise suppression1 package for one
    tractor model.  This package nedaced the level
    of noise at the operator's station from 96.5
    ofiA to 89.5 dBA.  According to the Welsh-Healey
    cumulative exposure formula, the total time an
    operator could be permitted to run the machine
    fn an 8-hour day was 2.9 hours.  The only way to
    meet the Walsh-Healey criteria without
    requiring the use at protective devices is ta
    enclose the operator in an acoustical Iy treated'
    cab.  The heavy structural elements of roll-
    over protective structures (RQPS), required
    under the Occupational Health and Safety Act as
    a necessary part of such cabs, make the noise
    suppression problem all the more difficult,
    since These are excellent transmitters of
    noise.  The following recommendations are
    presented:

    1) !~he EPA should not promulgate additional
    standards fair the protection of aperaTors
    untiI it is shown that the regu t at i ons of the
    Walsh-Healey Act of 7969 and ttie Occupational
    Safety and Health Act of 5970 can be met.
    2) Research should be initiated to acquire and
    analyze relevant spectator noise data, to the
    and that realistic and attainable spectator
    noise level criteria can be established.
    3) When the research has been completed, the
    EPA ahoLld establish uniform spectator noise
    level regulations which wil! be applicable
    nationwide.
    4) Hoi-form test procedures should be
    estabt ished for the measurement of both
    spectator and operator noise levels once
    standards have been established.  These
    procedures should be representative and
    reproducible.  A single Federal agency snould
    be responsible for both the prossulgatFan and
    enforcement of all noise regulations.
    5) Due to the difficulty of retrofitting noise
    suppression packages on construction equipment
    currently in the field, if any retrofit
    standards are set, they should be less
    restrictive than new product standards.
6) It is strongly recommended that regulations
with respect to spectator noise  level criteria
for construct i on mach i nery ncrt be app lied pri or
to 1974.   In a discussion which  followed, the
additional cost of developing new machines and
retrofitting older models was considered.  In
the final analysis, the increased cost would
ultimately be reflected in the product.
00-002

Jackson, E. l.

QeIta P. Incorporated

On:  CONTROL OF NOISE WITHIN THE CONSTRUCTION!
     INDUSTRY

Witness Statement
Public Hearings on Moise Abatement and Control

Atlanta, JUL 8, 1971
A discussion of state of the art  for  noise
control  in construction equipment is  presented
and recommendations are made for  the
implementation of existing methods and  devices
for noise abatement.  It is acknowledged that
si leocfrrg packages have been developed  and  are
available for construction equipment.   There
is strI I much work to be done  in  the  field  of
noise  control, but it- is also  necessary to
minimize the economic impact" on the
construction industry.  Technical  breakthroughs
are not  the major requirement.  The problem is
to get these standard silencing techniques
introduced universally  into the construction
industry.

The basic problem of noise control  is
economic.  Performance  is ncrr  improved  in
equipment or machines when silencing  is added.
Costs  varying from I to tO£ are typically
addsd  to the equipment and Fn  some cases
operating costs are  increased.  Various studies
have tried to prove that reduction of
Workman's Compensation, for example,  would  more
than offset the cost of silencing, but
management  is not convinced.   There  is  now  no
economic incentive to the construction
industry;  in fact, there  is a  penalty.
However, there are benefits for the  industry
through  improved performance,  (ess damage to
health through hearing  loss,  increased
productivity and easier and clearer
comnun i cat i orv.

The following recommendations  are presented:
Additional  legislation  with technical meaning
in quantitative terms and enforceable language
is needed.  The economic  realities of the
situation must be  understood.  Subsidies and
economic incentives  snould" te considered during
the transition period.  Analysis  and research
                                                         18

-------
                                                                                                         00-003
                                              EPA HEARINGS
into the problem are also needed to better
identify and solve these problems with specific
emphasis on how new concepts could lead to
quieter and better equipment.
total of $362 million annually, for a reduction
of 5 to 12 dBA.  A cost of $200 to $2000 for
parts plus the cost of installation is
estimated for the equipping of existing
vehicles.
00-003

Cod I in, J. B.

Al I is Chalmers Corp.,
Springfield, I L

On:  TECHNICAL ASPECTS OF SOUND CONTROL

Witness Statement
Public Hearings on Noise Abatement and Control

Atlanta, JUL 8, 1971
00-004

Walk, F. H.

Walk, Haydel and Associates, Ltd.,
New Orleans, LA

On:  NOISE  IN CONSTRUCTION OF INDUSTRIAL PLANTS

Witness Statement
Public Hearings on Noise Abatement and Control

Atlanta, JUL 8, 1971
 In this discussion of the problems of noise
control in the manufacture of construction
equipment, emphasis is placed on the cost of
these  improvements to industry and eventually
to the taxpayer.   It is estimated that 562,000
pieces of equipment are in operation and that
they generate $8 billion worth of construction
annuaIly.

The Construction Industry Manufacturers
Association (CIMA) has cooperated in the
development of measurement and control of
noise.   Included in the study were noise
measurement at operator's station, noise
measurement at 50  ft radius, construction job
site noise measurement, and cumulative operator
noise exposure measurement along with
standardized reporting methods.

Experiments on both short-term and long-term
methods for sound  control  are discussed.
Short term methods include mufflers, enclosing
engine, hood and covers lined with sound
deadening materials.   Many of these are not
durable, and when many sound deadening
materials become oil-soaked they are inflamable
which creates a definite fire hazard.  It is
necessary to weigh the tradeoffs in
serviceability, effect on reliability, safety
and cost.

Engineers are working on a long-range basis on
components such as engines, hydraulic pumps,
gearing of transmissions and piping to
determine what can be done at the source to
control noise.   To date, success has been
marginal.   The cost implications are high.
Machines have been analyzed component by
component, and most will require redesign and
retooling.  Estimates indicate that noise level
reduction  will  be 3-6 dBA at 50 feet.  The cost
impact  is estimated to be 10 to 25% per
vehicle.  The estimated long-range cost to the
public  is $202 million annually.  This, in
addition to the short-range program costs is a
A discussion of problems in reducing noise
levels in the construction industry is
presented.

Although much progress has been made in the
isolation and reduction of plant operating
noise, far  less progress has been made toward
noise abatement in the construction industry.
The average industrial plant construction
manager has been subjected to much less noise
abatement pressure than the average industrial
plant operator.  This is probably due to the
temporary nature of construction operation as
opposed to a long-term, permanent manufacturing
operation.

An improvement in the state of the art of noise
abatement in construction can be realized if
permissible standards of sound levels are
assigned to specific  items of construction
equipment.  Manufacturers should be required
to prepare sound pressure levels on a uniform
basis for all  types of equipment.  For each
type, operating conditions, distance-
measurement criteria, and directionality
characteristics must be developed under
controlled environment.  If noise abatement
programs are accelerated, careful attention
must be given to the establishment of
reasonable standards for the industry and also
to the planning of a timetable for stepwise
enforcement so that the costs of compliance do
not become excessive and further deter capital
expansion programs of industry.  A discussion
followed on the relative cost of developing and
jsing improved equipment and it was concluded
that it would be In the order of magnitude of
1C to 10?.
                                                    19

-------
00-005
                                                  EPA HEARINGS
    00-005

    Watts, J. A.

    Michigan University, Ann Arbor

    University of Michigan Law School

    On:  VEHICULAR NOISE CONTROL  LEGISLATION

    Witness Statement
    Public Hearings on Noise Abatement and Control

    Chicago, JUL 29, 1971
    A noise control project with participation by
    the University of Michigan's Environmental Law
    Society and Department of Mechanical
    Engineering is designed to develop enforceable
    noise control  legislation for various
    governmental bodies.   It  is primarily concerned
    with vehicular noise.

    Local and state police and highway officials
    were interviewed.   It  is concluded that the
    most important aspect of noise pollution
    legislation is the  problem of enforcement.

    Enforcement of noise control legislation  is
    expensive.  It requires special equipment and
    training.  Enforcement may be extremely
    difficult.  Weather changes affect measurement.
    Certification and calibration of  instruments
    may be extremely time-consuming.  The police
    want simple, reliable and inexpensive
    instruments which can be operated under varying
    conditions.  Until  this equipment is available,
    one solution may be to employ noise teams
    composed of a police officer and  a person
    trained  in noise measurement techniques.

    Definite  legislative standards are necessary
    to avoid the problems created by  the present
    statutes which prohibit "excessive and unusual
    noise".

    An effective solution to the noise pollution
    problem  is effective enforcement  of
    manufacturing standards.  There  is  little
    evidence that manufacturers will  reduce noise
    levels without government enforced standards.

    The following recommendations are presented:

    Federal  standards for vehicular noise should
    be established at the earliest possible date.
    Provisions should be included which allow for
    stricter state standards.

    Full matching grants should be made available
    to police and health departments  throu"k-''-
    the nation ^o < un-hase equipment  and train
    personnel  in noise  control.

    A system of tax  incentives  for the manufacture
    of quiet products should  be employed to
    ascertain  its feasibility.
The  long-term goal in the fight against noise
pollution should always be to reduce the noise
level and not merely to hold the  line at an
"acceptable" noise level.  And the  last
recommendation, additional Federal  highway
funds might be supplied for research on the
use of material for quieter road  surfaces.
00-006

Lew is, E.

Northwestern Students For A Better Environment

On:  NOISE POLLUTION AND EDUCATION

Witness Statement
Public Hearings on Noise Abatement and Control

Chicago, JUL 29, 1971
This statement, made by Northwestern Students
For a Better Environment (NSBE), is based on
information presented in Volume I  and in
preliminary drafts to Volume I I  of a study
entitled "Comprehensive Plan for the North
Lakeview Section of the Uptown  Model Cities
Area" (of Chicago).

This study, financed by grants  from the Sloan
Foundation and the National  Science Foundation,
was undertaken by students working through the
Urban Systems Engineering Center and the
Design and Development Center,  both at
Northwestern University.

Noise Pollution in North Lakeview affects many
patterns of human existence.  But,  its effects
on safety and education are the most
d i sturb i ng.

It was observed that children could not hear
approachingg cars and that noise from the
elevated trains of the Chicago  Transit
Authority (CTA) frightened them.  A more
serious noise pollution problem with many
unknown effects is disruption of classrooms.

The following recommendations are made about
the level of noise generated in one Chicago
community area:

The Walsh-Healey Act should be  amended so
workers are better protected from hazardous
noise levels.  NSBE recommends  the adoption
of 80 dBA, as proposed by the New York State
Quiet Communities Program, as a maximum level
for prolonged periods.

Second, EPA should adopt Sound  Transmission
Class levels.  The STC  level is the  level of
sound which building materials  baffle.  EPA
should adopt STC  levels for building materials
that will reduce noise  levels below the 80 dBA
level.
                                                         20
                                                          t

-------
                                                                                                          00-007
                                              EPA HEARINGS
Third, EPA should perform additional research
on the effectiveness of baffles and concrete
supports which are used for noise abatement
around CTA tracks.

Finally, a new friction reducing compound
should be developed.  This compound will help
reduce noise  resulting from rail-wheel
interaction on the elevated tracks.  A
demonstration grant from the Federal government
may  lead to an inexpensive means of reducing
decibel  levels.
 00-008

 Spahr,  H.

 Park  Ridge,  IL

 On:   AIR,  NOISE, MEASUREMENTS AND PROCEDURES

 Witness  Statement
 Public  Hearings on  Noise Abatement and Control

 Chicago, JUL  29, 1971
00-007

Corbett, J. J.

Airport Operations Council
International, Washington, DC

1700 K Street, NW, 20006

On:  AIRCRAFT NOISE POLLUTION AS A NATIONAL
     PROBLEM

Witness Statement
Public Hearings on Noise Abatement and Control

Chicago, JUL 28,  1971
Aircraft Noise pollution is viewed by
governmental airport operators as the single
greatest constraint to orderly aviation
development in the 1970's.   New airport
capacity is stalled across the nation and
around the globe primarily because of
understandable community and public
disaffection with the noise of current day
aircraft.  The single most beneficial step
offering promise of noise alleviation is
accelerated Federal applied research toward,
and a prompt Federal  decision regarding, the
retrofit of the existing jet fleet, primarily
for those aircraft whose useful  service life
exceeds 5 years. The international and
interstate nature of air transportation
requires that action to mitigate aircraft noise
be concentrated on reduction of noise at its
source, the aircraft engine, and that Federal
or international action, and not  inconsistent
state/local measures, be expedited.
The City of Park Ridge  has been monitoring
aircraft flights originating from O'Hare
 International Airport flying over the
community since  1963.   In  light of this, Park
Ridge adopted an ordinance which essentially
provides that flights over portions of the
city causing noise  in excess of 95 dBC are a
nuisance.

To  implement the provisions of the ordinance,
a bubble top truck  equipped with a sound
measuring device and a  radio capable of
monitoring air traffic  was obtained and was
designed so that visual observation of flying
aircraft could be made  conveniently.

The sound truck and equipment  is generally
operated by a member of the Park Ridge Police
Department who has  received specific training
in the use of the equipment.

A consulting acoustical engineer has evaluated
the noise measuring program and has determined
that the measurement techniques of Park Ridge
officials are sufficiently good.

Complaints appear completely justified since
levels which evoke  complaints are equal to or
in excess of the 85 dBA 'critical' or 'danger'
level.

A simple, easily demonstrated case can be made
to show that present aircraft operations at
O'Hare already expose community areas to
dangerous noise  levels and that the proposed
plans for additional runways at O'Hare will
increase the exposure levels and the affected
geoographicaI  area.

The schools of Park Ridge find the
inconsistency and high  level  of noise pollution
attributable to the expansion and lack of
pattern control  at  O'Hare  International Airport
becoming increasingly less tolerant in the
educational  setting.  In general, it was
determined that modification in the teachers'
approach to instruction are necessary.
Particularly where  a combination of verbal  and
auditory faculties are needed,  the teacher is
forced either to shout or, by preference, to
discontinue communication until the noise
subsides.  Valuable instructional  time is lost
and crucial  learning activities are set adrift
as concentration is broken and  young minds
wander to the source.
                                                    21

-------
00-009
                                                  EPA  HEARINGS
     00-009

     Rupert,  H. M.

     Federal  Highway Administration,
     Washington,  DC

     Zip  20591

     On:  CONTROL OF HIGHWAY RELATED NOISE

     Witness  Statement
     Public Hearings on Noise Abatement and Control

     Chicago, JUL 28,  1971
    The  highway  related noise problem and some
    potential  solutions are presented.  The control
    of this  nuisance  requires the concerted and
    coordinated  efforts of many programs, agencies,
    firms and  individuals.

    There is good  reason to believe that quieter
    vehicles can be manufactured.   If the
    manufacturing  industry were furnished
    reasonable noise  criteria which would be
    uniformly  applied to all manufacturers,
    improvement  could be obtained without
    jeopardizing the  sales and profits of any
    indivi dual fi rm.

    The  President  has recommended Federal
    legislation  which would enable this control.
    A bill has been introduced in Congress to
    provide  this authority to the Environmental
    Protection Agency.

    If the manufacture of quieter vehicles were
    required,  there is no assurance that they would
    remain quiet.  Most State motor vehicle codes
    require  that a vehicle not be operated without
    a muffler  or in a manner which creates loud
    or excessive noise.  The determination of what
    is  loud  or excessive requires a subjective
    determination  on  the part of an enforcement
    official.  As  a result, enforcement is
    difficult  and  ineffective.  The Federal Highway
    Administration recommends State and local
    enactment  and  enforcement of numerical noise
    level Iimits.

    Reduction  of the  noise which the vehicle
    creates  will not  eliminate all highway related
    noise problems.   An amphitheater should not be
    constructed  near  an airport or adjacent to a
    heavily  travelled freeway.  The same is true of
    some types of  single family residences, some
    types of schools, hospitals and many other
    types of  land  use.

    Land use control  in areas where noise  is a
    problem  should be considered.  The  lands need
    not  necessarily remain vacant.  Most
    commercial and industrial activities can be
    made to  conform to a noise environment.

    Sometimes  the  local officials who control  land
    use, planning, and  zoning are not aware of  the
    potential  noise  in  these  situations.
    Transportation officials  must continue to
cooperate with local officials, informing them
of potential areas of incompatibility, and
helping to plan compatible activities.   In
addition, a national land use policy, with
built in incentives to localities is needed
to insure compatible land use development.

The Congress has directed the undertaking of
some enormous tasks with the enactment of the
Federal-aid Highway Act of 1970.  One of these
tasks is the development of guidelines to
assure that adequate consideration is given to
the social, economic and environmental effects
in the Federal-aid highway program.   One of the
specific effects the Congress wanted  included
is noise.

There is great potential  in the guidelines and
standards efforts for further increasing the
highway program's responsiveness to the
current concern for the environment.  However,
great care must be taken to be certain that
they are not so severe as to cause a serious
impediment to the highway program.

The noise guidelines are expected to be a
procedure for analysis of noise impacts.
Included in the analysis would be:
(a) determination of existing noise  levels,
(b) inventory of noise sensitive  land uses
or activities, (c) prediction of anticipated
noise levels from the proposed highway project,
and (d) study of noise abatement alternatives.
The results of the analysis would be  furnished
to the decision maker together with the
analyses of other social, economic, and
environmental effects to provide a more
comprehensive basis for making highway
deci sions.

The noise standards are expected to be
numerical noise  levels (in decibels using the
A-weighted scale) for various land uses and
activities.  There will be different  values
for day and night, and there will be  both
average and peak noise levels.

There are several opportunities available for
control of noise during the development of a
highway project.  During the  location studies,
the potential noise impact of each alternative
alignment can be determined.  From a  noise
standpoint, the alignment having the  least
noise impact should be selected.

The design of a highway offers additional
opportunities to control highway  related  noise.
The advantages of a depressed roadway can be
considered.  The same  noise  level reduction
can be obtained  by  construction a noise  barrier
at much  less cost.

Landscape  plantings are  an aesthetic  asset  to
almost any  highway  setting.   Some noise
reduction  can  be obtained  by  avoiding steep
roadway  grades  and  by  holding their length
to  a  mini mum.

New acoustic  materials are needed for highway
work.  They  must be durable,  attractive,
economical  and  easily  cleaned.   Truck exhaust
                                                         22

-------
                                                                                                         00-010
                                             EPA  HEARINGS
stacks must be gotten closer to the ground so
that low barriers will  be more effective.
Pavement surfaces must be developed that are
both quiet and safe.

A last resort capability is needed which could
be used when all  other techniques are
inadequate or uneconomical.  Possible
approaches might include authority to purchase
noise easements or noise rights, the outright
purchase of a property, or installation of
noise insulation.
00-010

Ringham, R. F.
Staadt, R. L.

International Harvester Company,
Chicago,  IL

Chicago,  IL

On:  HIGHWAY TRANSPORTATION NOISE

Witness Statement
Public Hearings on Noise Abatement and Control

Chicago, JUL 28, 1971
Typical truck noise and its sources and
measures involved in controlling it are
reviewed.  The overall  approach to legislative
control of highway vehicle noise is also
discussed.  Criteria for regulations must
reflect test conditions and procedures
specified for verification of compliance.

Vehicles which contribute the most to highway
noise are the large diesel  powered trucks.
Several noise sources are inherent in these
units:  exhause noise,  cooling fan, engine air
intake, engine mechanical  and combustion, and
tire and wind noise.

If certain sound sources are eliminated; for
example, the 84 dBA exhaust noise by a
theoretically perfect muffler, the total noise
level would only drop to 86 dBA.  Similarly,
if other single sources are eliminated, only a
slight drop in overall  noise is realized.
Since exhaust noise cannot be eliminated
completely, the only approach which can reduce
overall levels is to lower all  sources which
individually approach the level of the total.
Such an approach was taken in the case of the
88 dBA vehicle.
2) A larger, more efficient muffler reduced
exhaust noise.

3) The air intake noise was reduced by an
improved silencer relocated from the side of
the hood to the front to direct sound away
from observers.

4) Shields around the engine compartment now
block engine radiated mechanical and
combustion noise.

The resulting overall noise level  is now 86
dBA.  It is noted that most of these
modifications required considerable redesign
thereby making retrofitting extremely expensive
i f not impossible.

The value of 86 dBA  is considered to be the next
plateau in heavy truck noise control.  Major
cooling fan development programs and further
engine shielding will be required to meet this
level.   To get below 86 dBA will involve
extensive programs in engine and cooling
system redesign and development.  This will
involve several years and can reflect
considerable increase in cost to the user.

Regulations or sound limits for the vehicle
user should not be lower than those required
of the manufacturer or user at the time the
vehicle was built.  The operator,  or
manufacturer, for that matter, has no means
of making the vehicle quieter than it was
when originally built.  As shown earlier,
significant sound reductions by retrofit
programs generally are not practical.

Regulations cannot be effective without proper
enforcement.  Enforcement personnel  must be
trained in noise surveillance and operate at
the carefully selected sites which are
required for accurate readings.
00-011

Walker, B.

Cleveland, Ohio

On:  PREREQUISITES FOR NOISE CONTROL
     REGULATIONS

Witness Statement
Public Hearings on Noise Abatement and Control

Dal las, AUG 19, 1971
The measures employed were:

1) The cooling fan was run at a slower speed to
reduce fan noise and radiator size increased to
offset the loss in cooling air flow.
An environmental  health commissioner discusses
the sources of residential  noise and
requirements of an effective noise control
program.
                                                    23

-------
00-012
                                                  EPA  HEARINGS
     In contrast to older dwellings, the modern
     dwelling with  its  light weight construction,
     open  plan  design and multitude of noise makers
     provides very  little protection from noise
     generated  within or intruding from the outside.
     Data  from  a survey conducted  in Cleveland
     indicated  that 8055 of the  1000 respondents
     were  disturbed by noise outside the building
     and  16$ by noise from adjoining apartments.

     Zoning ordinances are of  limited value in
     controlling urban noise, as they simply
     aggregate  similar  land use activities, as
     residential, commercial and industrial, and
     tend  to  ignore peripheral  areas and factors
     such  as transportation.  These are reasonable
     grounds on which to question the adequacy of
     local government,  left to  its own resources,
     to control urban noise effectively.

     The alleviation of the noise problem frequently
     requires action that transcends political
     boundaries.  A broad-based, coordinated attack
     on the problem must involve the Federal and
     state levels of government.   It is practical
     and highly desirable to establish Federal
     standards  for some  items moving in interstate
     commerce to eliminate noise producing features
     at the point of origin or  at the point of
     manufacture rather than expect local control
     once  the equipment  is operating in a community.
     The critical areas of continuing research,
     manpower,  training and development criteria,
     demonstrations and funds for  local surveillance
     and monitoring require the full and effective
     leadership of the Federal  government.

     There are  shortcomings in our present knowledge
     and programs for noise control, and if we are
     to minimize additional environmental stresses
     on community living, a coordinated attack on
     the problem must be developed now.  It is
     essential  that nationally  accepred techniques
     be developed for the measurement, evaluation
     and rating of noise and  its effect on human
     health, and to accomplish  this will require
     scientific talent, trained technicians and
     additional facilities and  financial resources
     at all  levels of government.
Examples of ignorance of architects and
building mechanics in construction techniques
to reduce sound transmission are presented.
Some suggestion for activities of EPA  in this
field are out Ii ned.

A new hi-rise apartment was advertised as
having "revolutionary soundproofing."  In
reality the noise was worse than some old
tenement houses.  The load bearing walls had
a 62 STC rating but the others were on 35 STC
and poorly designed.

In another case, a hospital, the penthouse
machinery was not properly isolated.  After
four years professional  help was sought and the
problem corrected very easily.

Another example is post-tensioned concrete.
Using this method of  construction, floors can
be thin and supports  far apart.  The buildings
vibrated violently.  Everyone blamed someone
else.  It was eventually corrected, but much
time and money was wasted.

Two practical  methods to both  lower cost and
noise are presented.   The first entails
eliminating wood floor and placing carpeting
over the slab.   The second is changing from a
lead oakem joint in the waste pipe system to
a neoprene gasket.

EPA could disseminate available information on
architectural  design  on isolation.  Simple
consumer bulletins could be sent that would
help in consumer understanding.  The EPA should
act as a clearing house for new products that
will  help build quieter houses, such as the
neoprene gasket.  Some EPA media is needed
through which home-builders could be reached,
since they are the environment builders.    If
the builders could be reached through some
simplified type of do-don't corrective
mechanisms, they could be put  into effect very
quickly.  Time is a great concern.
     00-012

     Spano,  B.

     Polysonics  Acoustical  Engineers,
     Washington,  DC

     On:   THE STATE  OF  THE  ART,  HOME  NOISE

     Witness Statement
     Public  Hearings on Noise  Abatement  and Control

     Dal las, AUG 19, 1971
00-013

Wegner, R. L.

North Texas CounciI  of Governments

On:  REGIONAL AIRPORT PLANNING

Witness Stafement
Public Hearings on Noise Abatement and Control

Dal las, AUG  19, 1971
The efforts of a regional organization, the
North Central Texas Council of Governments
(NCTCOG) to help local governments deal
effectively with the challenges and
opportunities posed by the new Dallas/Fort
                                                         24

-------
                                                                                                         00-014
                                              EPA  HEARINGS
Worth Regional  Airport are discussed.  This
airport will  have the capacity to accommodate
300 aircraft  movements per peak hour.

The Regional  Airport Environs study stressed
the impact of aircraft sound on the development
of surrounding land.  An aircraft sound
exposure map  was prepared.  A brief simple
explanation of the significance of the sound
zones depicted on that map was prepared for use
by local officials concerned with land
development in the areas immediately adjacent
to the Regional Airport site.

Several seminars were held for planners,
administrators, building inspectors, and
representatives of school districts, which
gave technical  facts and guidance, recommended
land uses and  information about acoustical
treatment of  buildings.

Another project, funded by the Department of
Housing and Urban Development and entitled the
"Cooperative  Program of Planning for Airport
Impact," was  designed to help the cities most
directly affected by the new airport to carry
on local planning in response to airport
impact.  The  city of Irving developed an
Airport Zoning Ordinance and soundproofing
modifications to its building code.  The
soundproofing modifications will add 2 to 10?
to the cost of a building.

Another project of NCTCOG is the Cooperative
Planning Program, in which a number of model
codes and ordinances and guidelines are being
prepared to aid local governments in improving
their  local planning capability.

It is suggested that both preventive and
remedial measures to control, reduce and/or
eliminate the harmful effects of noise become
the concern of all  professional planners and
official planning agencies.   To plan
preventive and remedial measures planners and
planning agencies require legal authority,
political  sanction,  technical and financial
assistance.  Federal legislation should make
provisions for technical training and
financial  assistance and incentives for noise
control and abatement planning at state,
regional and  local  levels as part of the
environmental  protective activities at each  of
these  levels.   Approximately $6,000,000 per
year would provide an average of $25,000 to
each of the 240 standard metropolitan areas.
Assured funding of this type would establish
a  sound foundation  and a start toward
deliberate, continuing environmental  protection
activity at the regional level.
00-014

Hixon, E.

Texas University,
Austi n

On:  NOISE ISOLATION IN LOW COST HOUSING

Witness Statement
Public Hearings on Noise Abatement and Control

Dal las, AUG 19, 1971
In 1968, 10 single family, low-cost dwellings
were constructed in Austin, Texas, under the
sponsorship of the U.S. Department of Housing
and Urban Development.  The purpose was to
develop and test architectural  design,
building materials and construction methods.
The University of Texas was asked to provide
architectural, engineering, psychological  and
sociological evaluations of these houses.
Noise isolation studies were conducted as  part
of the engineering evaluation.

Standard FHA specifications were waived to
allow innovations.  Ten plans utilizing a  wide
range of materials and construction methods
were chosen.  Most of the acoustic tests were
made after the houses were occupied by the
purchaser.   Test results for 6  of the houses
indicate generally low values of noise isolation
and lack of consideration for noise isolation.
In some cases simple changes that would add
little to the cost could have resulted in
large improvements.   It is concluded that
noise isolation should be a major consideration
in housing  for low-income families who have
the greatest need to enhance the quality of
I ife.
00-015

Parrott, C. D.

Redevelopment Authority
La Crosse, Wl

On:  THE RESPONSIBILITY OF THE URBAN PLANNER
FOR NOISE CONTROL

Witness Statement
Public Hearings on Noise Abatement and Control

Dal las, AUG 19, 1971
                                                            The  selected  placement  of  potential  major
                                                            noise  producing  activities  to  protect the
                                                            urban  dweller and  his neighborhood  environment
                                                            is discussed.  Regulatory measures  governing
                                                            intensity  of  land  use,  control  limits on  sound
                                                     25

-------
00-016
                                                  EPA HEARINGS
    producing devices, and sound reduction
    engineering and architectural designs for
    transportation facilities and certain other
    forms of  land use are required to supplement
    selective placement.  With the systematic
    application of these controlling factors and
    the public's understanding of the need for
    such measures, the mounting threat of sound
    pollution can be reduced.  The urban planner
    is In a unique position to help educate the
    public and the elected and appointed officials
    he serves.

    The City of Madison, Wl, has adopted a code
    setting maximum noise levels for all
    stationary and moving noise-producing devices
    in all zoning districts and public ways with
    the only apparent exceptions being emergency
    vehicles and fireworks displays.

    Transportation planners should not be preparing
    plans for communities which call for the
    construction of high-speed freeways and
    expressways in association with residential
    land use.  Any freeway network in an urban area
    may pass through commercial, industrial,
    residential, agricultural and other types of
    land use areas.  Although normal noise levels
    from freeway sources may be acceptable in an
    industrial area, these same  levels would be
    less acceptable in a residential area.  From
    the economic standpoint, it  is difficult to
    justify the costs of purchasing additional
    widths of right-of-way to protect residents
    from the adverse effects on high speed freeway
    facilities at this point in time.

    People generally have little or no knowledge
    of the possible effects that various types of
    installations can have on their environment
    until the conditions are experienced, and then
    it is too  late.  Therefore,  it  is  important
    that the  planning profession be sufficiently
    informed on all environmental considerations
    and take  these factors  into  account  in their
    studies,  in their reports, and  in their
    explanations to the public officials.

    Land use  controls, density controls, public
    property  acquisition, and building code
    soundproofing requirements for construction
    in undeveloped areas near freeways and
    airports  can employ  limited  defensive
    measures  against excessive sound.  The problem
    near transportation facilities already
    surrounded by urban development  is
    significantly more complicated.  Preventive
    measures,  however unpopular, are far  less
    costly and difficult than corrective actions.

    The requirements for moving  traffic and
    aircraft  will be greater  in  1990 and the year
    2000 than  they are today; but, also,  it must be
    acknowledged that the requirements for
    preserving our environment will also be much
    greater than they are now.   Somewhere we must
    turn the  corner and make planning  for  the
    integrity of our natural environmental
    resources  and the people they  serve  and protect
    as commonplace as the planning  for  residential.
    Industrial and commercial areas and
    transportation facilities.
00-016

Tanner, C.

Hydrospace Research Corporation,
San Diego, CA

On:  MEASURING TECHNIQUES FOR NOISE STANDARDS

Witness Statement
Public Hearings on Noise Abatement and Control

San Francisco, SEPT 29, 1971
This discussion deals with the measurement
techniques for use in certain airport noise
standards.  These techniques are based on the
measurement and processing of noise signals to
define the 3 basic properties of noise:
     1.  Absolute level
     2.  Frequency content
     3.  Time variations

The resultant measurements are used in a
variety of computational procedures to assess
not only the basic nature of the sound signal,
such as defining a pure tone component, but to
evaluate the subjective annoyance of a sound
by calculating effective perceived noise  level
or noise exposure levels.

Each noise standard sets down some rather
detailed specifications regarding:

     1.  The instrumentation that can be used,
     2.  Calibration measurements,
     3.  Physical location of microphones,
     4.  Operating limitations, and
     5,  Signal processing and computational
         requi rements.

Measurement requirements for the Federal
Aviation Regulation Part 36 which specifies
the effective perceived noise levels of
commercial aircraft, require microphones at 3
sides and the measurement of the noise of at
least 6 take-offs and 6  landings.  These
measurements are processed to define the
frequency distribution and energy  level every
one-half second.  These values are corrected
and used to compute perceived noise levels
which are compared with the allowable  limits.

The measurements for the California Noise
Standards require that at large airports
microphones are located at 12 sides and
measure the noise above a specified threshold
from every operation.  Using an updated
summation for specified time periods of the
day, the composite noise equipment level is
computed.  This level  is compared with
previously established  levels around the
a Irport.

Although there are a number of measurement
techniques that are used in implementing noise
standards, all are subject to outside
Influences which must be recognized in order to
                                                         26

-------
                                              EPA HEARINGS
                                                                                                         00-017
maintain data quality.  Background noise can be
of sufficient  level to  invalidate the
measurement.
00-017

Olpin, 0.

Utah Univ.,
Salt Lake City

On:  REDUCTION OF TRANSPORTATION NOISE

Witness Statement
Public Hearings on Noise Abatement and Control

Denver, SEPT 30, 1971
of that money is allocated to the search for
cures.  Concrete proposals looking toward
cures should be made by the Environmental
Protection Agency at the earliest possible
moment.  It is necessary to adopt laws and
rules and regulations which will impel the
transportation industries and the consumers
of their products to shoulder their share
of this burden.   Another proposal that should
be considered is to use in this effort part of
the substantial  resources of the Highway Trust
Fund.

The Highway Trust Fund represents a practical
and appropriate source of support for the
solution of the problem of noise from
transportation.
Noise pollution from transportation, cars,
trucks, and airplanes  is discussed.  Engine
sounds from vehicles have been control led for
years by mufflers, but the market has  not
provided the  incentives needed to bring about
improvement in muffler technology.  The aim has
been to protect the motorist from noise
pollution  inside the car with windows  shut;
but not those on the outside near the
highways.

A  large part of the sound of the highways is
the sound of wheels rolling on the surface of
roads.  This  is not an unsolvable problem,
but today neither the pressure nor the market
incentive  is present.  The task  is to  create
both.

An obvious partial  solution lies in measures
to assure that presently available technology
is fully utilized.   In the case of mufflers
or other vehicle sound controlling equipment,
this can easily be made a part of existing
licensing and inspecting procedures.   Laws
should be made firm enough to require  that
licenses be denied to any vehicle not  equipped
with adequate, properly functioning sound
control devices.

A special problem is posed by noise generated
by recreational  vehicles.  Some seem to believe
that more sound means more power, and  appetites
for both sound and power seem considerable.
Motorcycles, dunebuggies, dragsters, and
snowmobiles appear to be manufactured  and
operated with a purpose to maximize sound
production.  There is available technology to
muffle most of the sound generated by
recreational vehicles.  Up to now, however,  laws
have not been passed.
Title IV of the Clean Air Act provides for a
beginning in the battle against unwanted
sound.   Authorization is provided for
$30,000,000 to begin to identify causes and
sources  of noise and to learn of the damage
and injury which results from noise.  No part
00-018

Monaghan,  J.

Colorado State Univ.
Fort Col I ins

On:  RECREATIONAL NOISE

Witness Statement
Public Hearings on Noise Abatement and Control

Denver, SEPT  30, 1971
The pervasive noise created by such
recreational vehicles as snowmobiles, motor
powered boats, all  terrain vehicles and the
like is discussed.   The high decibel  output
from some of the aforementioned recreational
sources is the antithesis of bodily and mental
refreshment.  The various concepts of
recreation seem to be on a col I ision  course.
Psychologists tell  of the mounting need for
periodic escape from the urban environment
as a survival mechanism.  Some animals and
plants are up to 30,000 times more sensitive
to noise than humans.

Noise is a national problem, and recreational
noise, produced by vehicles that are
manufactured and distributed nationally,
would be more easily regulated with uniform
requirements that manufacturers would have to
meet on a national  basis.   It is also felt
"that on a local  level the health and  individual
rights of those seeking an outdoor experience
could easily be subjugated by local interests
focused narrowly on the monetary gains of these
loud vehicles.

The Environmental  Protection Agency is urged
to promulgate regulations for recreational
noise wifhin a comprehensive noise control
program and include:  1) the establishment of
uniform decibel  limits on all  recreational
vehicles, whether manufactured in the United
                                                     27

-------
00-019
                                                 EPA  HEARINGS
    States or imported; 2) a provision for research
    of the state of the art in noise abatement
    for recreational vehicles; and 3) the provision
    for the periodic testing of such vehicles which
    are already in use; 4) the concept of
    differential use and noise zoning.

    Decibel limits must be realistic within
    existing technology.  But the freedom of the
    individual to enjoy a recreational experience,
    unhampered by an obnoxious environment, is of
    key importance.  The concept of differential
    use and noise zoning is encouraged.  In This
    manner, certain lakes, for example, would be
    zoned for such vehicles,  setting in each case
    realistic decibel  limits.
    00-019

    Lincoln, R.

    Outboard Marine Corp.
    Mi Iwaukee, Wl

    On:  MOTOR NOISE CONTROL

    Witness Statement
    Public Hearings on Noise Abatement and Control

    Denver, OCT  1, 1971
    A statement from a manufacturer of snow
    vehicles, outboard motors, lawn and garden
    equipment, all terrain vehicles, chain saws
    and golf carts is presented.   The extent to
    which regulation of noise will help reduce
    annoyance and contribute to the improved
    quality of life is of major concern.  Noise
    reduction is not as simple as adding or
    enlarging exhaust mufflers or building better
    enclosures.  Time, talent and money are
    required to make a detailed technical  analysis
    of each product.  Strict, fair and uniform
    enforcement codes are a must.  Without them,
    manufacturers whose products do conform to
    regulations will suffer severe penalties.

    Noise levels of typical  leisure time products
    have been examined and  it has been noted that
    technology can probably be developed which will
    reduce complaints stemming from annoyance.
    These reductions will penalize the product
    user  in cost, weight, bulk, ease of handling
    and simplicity of service.  Regulations and
    standards can be established which will be
    realistic and feasible, but there are many
    complexities  to be considered  if fair and
    equitable enforcement  is to be maintained.
    Since many complaints about noise are from
    members of small, special  interest groups,
    great care must be taken to assure that  large
    numbers of people are not penalized to satisfy
    a  few.
00-020

Yoerger, R.

I I Iinois Un iv.,  Urbana

On:   AGRICULTURAL EQUIPMENT NOISE CONTROL

Witness Statement
Public Hearings  on Noise Abatement and Control

Denver, SEPT 30, 1971
Scientific and engineering developments have
contributed to increased productivity and
reduced drugery of work on the modern farm.
However, the relative economic position of the
farmer, compared to his industrial  counterpart,
has deteriorated over the last 30 years.
Before any noise regulations pertaining to
agriculture are enacted, the cost benefits
ratio must be carefully evaluated.

The farm equipment industry produces $4-
$6,000,000 worth of goods annually.  The large
manufacturers have engineering and  research
facilities.  The small  manufacturer must solve
problems on a local level  and is able to
develop and modify machines quickly.  Often
the small  manufacturer develops new machines
and establishes the market potentials before a
major manufacturer is willing to commit the
resources necessary to add the item to his line.

In the past, equipment demanded by  the consumer
each year had to be larger, operate faster and
have a greater capacity than earlier models.
Because the industry has met these  demands,
productivity per worker has increased markedly.
In 1960, one farm worker produced enough food
for 26 persons; in 1970, enough for 46.  The
result of building bigger machines  has
generally been an increase in the sound power
level of noise associated with machine
operation.  Major contributors to the overall
noise level of an operating machine are the
power source, the gear train and the various
functional components of the machine.

Industrial, professional and public service
groups have been concerned about the
identification and reduction of equipment
noise for some time.  A research program at the
University of Illinois  is concerned with the
noise and vibration associated with farm and
industrial machinery.  The research at the
University of Illinois has been concerned with
reducing 2 of the major components of tractor
noise, that resulting from the cooling fan and
from the engine exhaust.  The goal   is to better
understand the mechanism of generation and
transmission of these noises and to reduce the
levels as close to the source as possible.
It is felt that the goal with agricultural
machinery should be to  reduce noise  level so
that there  is not a serious potential hazard
to hearing  loss for either the machine operator
or for associates working  in close  proximity to
the  machine.  Agricultural universities, the
                                                         28

-------
                                              EPA  HEARINGS
                                                                                                         00-021
farm equipment industry, 4-H and FAA groups and
others are cooperating  in an educational
program to alert the farmer and farm worker to
potential  hazards and in merchandising ear
protective devices.

Each piece of new mobile equipment should carry
a nameplate certification of maximum sound
power  level generated by that equipment in
operation.  A consumer should be able to get
some idea of the noisiness that will result
from the operation of the equipment before he
buys it.  On the national level, the goal
should be "to work toward maximum allowable
values of sound power emission for new
equipment that would not present hazards to the
operators or to the bystanders.

With this proposed procedure, the manufacturer
would be faced with a single, uniform criteria
for all equipment sold throughout the United
States, and he would be responding then to the
consumers' wishes by competing with his
associates to produce more desirable equipment.
It seems that this is the best kind of
regulation that can be developed.  The state,
municipal  and local bodies can then deal with
the manner in which equipment is operated, and
the resulting sound pressure levels that occur
with their operation.
00-021

Martin, T.

Boulder, CO

On:  ENFORCEMENT OF NOISE CONTROL ORDINANCE —
BOULDER, CO

Witness Statement
Public Hearings on Noise Abatemerrt and Control

Denver, SEPT 30, 1971
standard.  The snowmobile  industry has been
notified  in many ways that  it has to quiet  its
product.  Federal pressure  could eliminate
this problem.

The noise standard used  in  residential areas
is measured from 25 feet and has been  in effect
since February,  1970, in Boulder.  More than
1300 vehicles have been  repaired or modified to
meet the Boulder standard.   It  is predicted
that unless quieter motorcycles are produced
and other methods are found to quiet the older
cycles, much of this nation will become off
limits to them.  This noise  level must be
brought lower than 80 dBA.  Trucks are allowed
88 dBA at 25 feet and do not use residential
streets at night.  Industry has been amazingly
flexible and responsible to  legal requirements.
Individuals, once educated, are just as
responsive.  When the Boulder program began,
eight motorcycles out of 100 were being stopped;
now, one out of 100 is the  average.   One
automobile out of 166 was  initially in
violation; presently, it is one out of 301.

Construction noise in most  cases has been
easily corrected.  Most of  the excessively
noisy equipment was leased, and the basic
problem was insufficient muffling.  In a few
years, with proper Federal  legislation, this
should cease to be 
-------
00-023
                                                 EPA  HEARINGS
    children was probably noise induced.  Sixty-
    three percent of the noise induced-like loss
    first appeared  in the junior-senior high age
    group.  Of these, 8% suffered a hearing loss
    progression of  10 dB.  About 5 times as many
    males as females suffered from this hearing
    loss pattern.

    The greatest percentage of children with
    hearing loss came from areas where  large farms
    using heavy equipment were located and where
    many engaged in hunting.  In a less affluent
    section where farms were small and not
    mechanized, the children showed much less
    hearing loss until fire crackers became
    available on a year round basis.   The
    percentage of children showing noise induced-
    like hearing loss rose from 22 to 37$.

    The State Department of Health has tried to
    make the public aware of this problem.
    Warnings are circulated to hunters, and
    physicians and parents of children.
    Individuals manifesting hearing loss are also
    warned of the dangers to hearing of shooting,
    recreational and agricultural  noise and
    encouraged to wear earplugs or ear muffs.
    00-023

    Knight, K. G.

    Institute for Rapid Transit

    Deleuw, Gather and Company
    Washington, DC

    On:  NOISE ABATEMENT PROGRESS  IN SUBWAY
         SYSTEMS

    Witness Statement
    Public Hearings on Noise Abatement and Control

    New York, OCT 21, 1971
    The  two  basic  acoustical goals of the rapid
    transit  industry are:  to provide system
    patrons  with an acoustically comfortable
    environment by maintaining noise  levels in
    vehicles and stations within acceptable
     limits,  and to reduce the impact  of system
    construction and operation on the community
    by minimizing  transmission of noise and
    vibrations to  adjacent properties.

    Notable  improvements  in the acoustical field
    have been made since the building of early
    transit  systems:

     1) The use of  continuous welded  rail has
    become standard  in  the  industry.

    2) Resilient track  fasteners have been
    developed to reduce both noise vibrations  in
    direct fixation track.
3) 'Floating1  track slabs are also being
developed for use in acoustically sensitive
community areas.

4) The importance of smoofh rail and wheel
surfaces is now well recognized.

5) The transit car of today is much superior
acoustically to its predecessors.

6) In underground stations particularly, noise
levels are being reduced and reverberation
times shortened by the use of acoustical
ceilings and under-train-platform absorption
systems.

7) Modern and attractive aerial  structures which
are replacing transit's old "els" are combined
with acoustically designed track fasteners and
will  be as quiet as they are attractive.

8) Sound barrier walls have been developed for
use on surface and aerial lines where
additional acoustical privacy is required.

9) Acoustical design criteria for ventilating
fan selection and fan and vent shaft design
are in general  use.

10) Ancillary mechanical  and electrical
equipment and facilities have been improved
with more attention being given to reducing
noise from this equipment.

Funds to make capital improvements in
existing systems are frequently  lacking.

Basic research is required to establish  more
clearly the effects of noise upon people and
to establish appropriate criteria for the
noises of the types generated by transit
system operations.  Equal effort should be
extended in educating the public and providing
them with information.  With an educated public
as our goal, criteria scales should be
standardized throughout the industry.  The
trend in criteria establishment seems to be
towards the use of simple, easy-to-measure,
A-weighted sound  levels, and this type of
standardization is desirable.

The transit industry concurs with EPA's
ultimate goal 'to achieve a desirable
environment in which noise  levels do not
interfere with man's health and well-being or
adversely affect other values which he  regards
highly.'1  However, the industry needs
assistance  in basic acoustical  research,  in
the development of new and  improved control
techniques and in the establishment of
economically attainable noise criteria which
may be easily comprehended by the public.
Additional financial assistance  is required
in order to modernize existing systems and
provide the basic noise and vibration controls
which are now attainable through technology.

Because of the wide divergence  in age and
character of existing rapid transit systems,
it is obviously impossible  to set a standard
that alI may follow.  There must be deviations
                                                          30

-------
                                                                                                         00-024
                                             EPA  HEARINGS
from the guidelines established in  order to
achieve compatibility.   It is believed that
transit officials recognize their obligations
to the community and that a system  of self-
imposed discipline in noise control,  supported
by the technical and financial  assistance of
government, will prove superior in  the long
run to enforced  legislation relative  to noise
vi brat ion.
00-025

McCollorn, H.

Hearing Conservation Center,
Lancaster, PA

On:  SOME UNRECOGNIZED NOISE PROBLEMS

Witness Statement
Public Hearings on Noise Abatement and Control

New York, OCT 22, 1971
00-024

DriscolI ,  J.

Hempstead  County Government,
Hempstead, NY

On:  AIRCRAFT NOISE ABATEMENT

Witness Statement
Public Hearings on Noise Abatement and Control

New York,  OCT 22, 1971
Suggestions on regulatory agencies and
procedures for control  of aircraft noise are
presented.  It is felt that noise is not only
a product, but a I so a problem of the
environment,  and its control  should be in the
hands of the Environmental  Protection Agency
rather than in the hands of the Federal
Aviation Agency.

A demonstration at Minneapolis-St. Paul  airport
is reported of aircraft operating procedures
which did achieve very noticeable lowering of
the noise levels of existing  aircraft in the
present jet fleet.   Purely  by  changing the mode
of operation  and pilot technique the planes
were quieter.

EPA is asked  to provide the impetus behind a
program which  will  in effect  regulate the air
carriers and  make them operate the present
aircraft in a  less  noisy fashion.   This  can be
done without  any  expenditures  of vast sums of
money.
A discussion of 3 examples of noise problems is
presented.  The first is the ultrasonic
vehicle motion detector used with traffic
lights to control  flow of traffic.  Its 18,000
Hz signal is in the upper level  of  human
hearing found in nearly all  children and many
young women.  At the lens opening a 120 dB
signal is produced.  Many parents are concerned
when their children scream and hold their ears
at certain highway intersections.

The second example is a hazard of the future.
The air bags being considred for automotive
safety will  inflate with a literally deafening
170 dB.  The presently available facts and
technology should be used to pre-plan against
noi se.

Thirdly,  the population of Lancaster, PA, has
not changed appreciably in 10 years.  However,
calls to the police concerning noise in the
month of August 1969 were 105, while in August,
1971 there were 189.   On a very  conservative
scale this extrapolates into a national figure
of $52,000,000 per year just answering noise
complaints.   These figures suggest  that noise
is  increasing without respect to population
growth or people are changing their attitudes
and complaining more or both.
                                                           00-026

                                                           Dougherty, J.

                                                           Harvard University,
                                                           Cambridge, MA

                                                           School of Pub!ic Health

                                                           On:  EXTRA-AUDITORY EFFECTS OF NOISE

                                                           Witness Statement
                                                           Public Hearings on Noise Abatement and Control

                                                           Boston, OCT 28, 1971
                                                           A discussion of the short-term physiologic,
                                                           apparently reversible, effects of noise and
                                                           the  longer term, usually irreversible effects
                                                    31

-------
00-026 (CONT.
                                                  EPA HEARINGS
     of noise,  and the common
     is presented.
,'inks  between the two
     The short-term physiologic  responses  to noise
     are quite similar to  those  found  with
     emotional  stress  in animals and man.  The
     similarities  have been  documented by  recording
     change  in blood pressure, pulse pressure,
     heart rate, perspiration, widening of the
     pupil,  or change  in fetal blood flow.  When
     blood or urinary  hormone  levels are assayed,
     noise again causes changes  similar to those of
     emotional  stress.  Blood  levels of long-acting
     hormones such  as  adrenocortiocoids (from the
     cortex  of the  adrenal gland) are  increased by
     noise.   Levels of shorter-acting  (adrenalin-
     like) hormones from the center of the adrenal
     and from nerve endings  are  also  increased.

     The strength of the response  is primarily
     related to either the dB  level or the
     emotional  content of  the  noise.

     Emotional  content of  noise  is a function of
     several  variables.  Among them are the
     individual's  previous experience  with or
     prejudice toward  a noise, the frequency, band
     width and rate of change  of this  change, the
     amount  of startle associated with the noise,
     the degree of  interference  with activity, the
     amount  of background  stress already
     experienced by the listener, and  the
     emotional  health  of the listener.  However,
     even without  any  awareness  of an  emotional or
     physiologic response  (in  some cases when
     anesthetized), the listener will  manifest most
     of  the  physiologic responses noted above.
     Clearly the willingness of  an  individual to
     cheerfully accept noise stresses  is no
     guarantee of  his  immunity to extra-auditory
     effects.

     Animals which  are exposed to chronic  noise
     stress  develop much the same disorders as are
     associated with emotional stress  in humans.
     Diseases such  as  arterial hypertension,
     arteriosclerotic  vascular disease, myocardial
     infarction, emotional instability and birth
     defects have  been caused  by experimental noise
     exposures in  animals.

     Several experiments have  been  performed which
     show the similarity between noise and other
     forms of stress in the  genesis of stress-
     related disease.   In  general,  the same
     hormonal and  central  nervous  system pathways
     are  involved.  No  experiment is  known  which
     has described a dose-relationship between
     noise and pathologic  effects.   However, when
     stimulation  of central  nervous  system pathways
     of animals was held to  the  same  level of
     physiologic  response  as seen in  humans with
     70-80 dB white noise, marked arteriosclerotic
     change  occurred in animals  fed  atherogenic
     diets.   These changes were  not  seen with the
     diet alone.

     Increased rates of a  number of  disease
     processes in  workers  subjected  to industrial
     noise have been described  in the  Russian
     literature.    In general these studies have  not
     been well controlled.
The need for well-controlled human studies is
further supported by the lack of experiments
performed with animals which — like humans —
have phlegmatic response to noise.  Studies of
the effects of noise stress on animals such as
dogs or primates would provide valuable
evidence for or against the role of noise in
stress-related human disorders.  The absence
of a causal link between noise and stress-
related disease in noise tolerant animals
and the paucity of well-controlled studies of
human exposure constitute the greatest
weaknesses in any attempt to indict noise as
the cause stress-related disease  in humans.

Only two studies have clearly linked noise
stress to human extra-auditory disorders.  In
one, performed on hospital  patients, those
recovering from myocardial  infarction
experienced 3 to 4 times larger adrenergic
hormone outputs following a standard noise
stress than other hospital  patients.  The
second paper dealt with admission rates to
mental hospitals from equivalent socio-economic
groups with the only known difference being the
flight paths to and from Heathrow Airport.
This airport is near London, England.  No
significant differences between noisy and quiet
areas were found in various subgroups of the
population except in older single women who
had the highest rate of admission in the quiet
areas.  Admission rates for this group were
significantly elevated (still higher) in the
noisy areas.  These studies are interesting
because they both demonstrate a heightened
susceptibility to noise in groups of people
who have demonstrated an increased
susceptibility to stress-related disease.

A number of areas for future research are
I  isted.

1) Do noise-tolerant animals such as dogs or
monkeys develop stress-related disease or
birth defects after exposure?

2) What role does the aging process play  in
effects of noise on animals or human stress-
related disease?

3) What are the effects of noise  upon
individuals with pre-existing disorders such
as arteriosclerotic vascular disease, diabetes
or emotional illness?

4) What is the relative importance of noise
stress among other environmental  stresses such
as automobile driving, excitement or anger,
diet or biochemical stresses such as
atmospheric  lead or cadmium?

Clearly such research would be multivariant,
would  require a number of years to perform and
would  be costly.  However, control of
environmental pollutants is costly and should
be based upon a priority ranking  derived  from
an estimate of the  relative costs or benefits
of each dollar spent for control.
                                                          32

-------
                                              EPA  HEARINGS
                                                                                                         00-027
00-027

Standley, D.

Boston Air Pollution Control Commission,
MA

On:  PROPOSALS FOR A NOISE ORDINANCE  IN BOSTON

Witness Stafemenf
Public Hearings on Noise Abatement and Control

Boston, OCT 27, 1971
00-028

Sutton, A.

Burgundy Farm Country Day School,
Alexandria, VA

On:  STUDENT RECOMMENDATIONS FOR NOISE CONTROL

Witness Statement
Public Hearing Noise Abatement and Control

Washington, NOV 12, 1971
The Boston Air Pollution Control Commission was
charged  in APR,  1971 with jurisdiction to
investigate, control and abate noise  in
Boston.  A report on noise was prepared by Bolt,
Beranek, and Newman, Inc. (BBN) under a
commission contract, in the  light of which the
Commission has drafted proposed interim
standards for community noise, and  initial
noise abatement  regulations, patterned closely
after "the Chicago ordinance.  A public
hearing  has been held, comments reviewed, and
the regulations  drafted.  The redraft is now
in review, and the sfandards and some
regulations will be adopted  in the  very near
future.

The Commission proposes that noise  in
residential areas attributable to land uses in
or abutting those areas be  limited  to
approximately 60 dBA in the daytime, 50 dBA at
night and on Sundays.  Limits on "the noisiness
of new motor vehicles, construction equipment,
recreational vehicles, and other powered
equipment for outdoor use are proposed.   These
take the form of certification requirements
imposed  at the point of sale or lease.  Still
being reconsidered is a restriction of the
noisiness of construction activities.  It is
felt that noise  from this source should not
exceed by more than 10-15 dBA the noise
standard for the area in which the  construction
occurs.  The framework for a system of
registration of certain noise sources and
rennits  for others is being developed.  It has
been possible, to date, to a! locate not more
than $25,000 per year to this noise abatement
act; vi ty .

A certification  requirement for motor vehicles
of 7'3 'fiA, at rifi foot,  :o be mot by 1980 is
EPA  is urged to take the lead in standardizing
measurement ,  test, and certification
procedures, and methods for expressing the
impact of noise.  Complete Federal preemption
of the sf andard-setti ng process is, however,
unnecessari ly restrictive of the right and
opportunity for communities to achieve the
environmental  quality they wish.
Suggestions for noise control from a group of
sixth, seventh and eighth grade students are
presented.  These students were completing a
science study unit on noise.  Some of the
suggestions were:  the passage of anti-noise
codes throughout the country, semi-annual
noise inspections for all vehicles, and strict
enforcement of a night curfew at Washington
National Airport; passage of  laws aimed at
stopping noise at its source; retrofitting jet
airplanes, quieter horns on motor vehicles;
production of quieter home appliances.  The
Washington Subway System should be made as
acoustically quiet as possible.  The
development of quieter drills and jackhammers
is needed.  Workmen around loud noises should
be required to wear ear plugs, until the
noise level around them can be reduced.  EPA
should sponsor a yearly national  anti-noise
week or day and is urged to develop a vigorous
campaign to educate the public.

A discussion of the course content followed and
it was suggested that EPA would be interested
in fostering further work about environmental
ecology at the secondary and primary school
level.
00-029

Goldshore, L.

New Jersey State Department of Environmental
Protection

On:  FEDERAL VS. STATE STANDARDS-PREEMPTION

Witness Statement
Public Hearings on Noise Abatement and Control

Washington, NOV 11, 1971
Testimony generally in favor of the bill,
S.1016, is presented.   Exception is taken to
Section 6(d), which appears to preempt the
adoption of state regulation of certain noise
sources.  This section raises some
questions regarding the relationship of Federal
                                                    33

-------
00-030
                                                 EPA  HEARINGS
    regulation and enforcement to State activities
    in the field of environmental protection.   It
    does not appear to be in the public interest
    to preempt a state from jurisdiction to protect
    its citizens from environmental  insults.   The
    Federal  Government does not have the manpower,
    or data  base, or the ability to take over
    environmental control.   It is suggested that
    S.1016 should be amended to allow for stricter
    state regulation if the state desires it.

    The following relationship between the States
    and the  Federal government is suggested:

    The Federal government  may adopt legislation
    which enables a national regulation of
    activities which can have a harmful impact on
    the environment.  The severity of these
    regulations should, however, serve as
    nationwide minimum, not as limitations. Thus
    those states that wished, could adopt more
    stringent regulations,  and enforce them.   This
    pattern  is important if New Jersey is to clean
    up its severe environmental problems.  New
    Jersey population density is the highest in the
    nation.   The state has  more vehicles per square
    mile than any other state in the union.  If the
    Federal  government were The sole regulatory
    body, New Jersey would  be governed by the  same
    regulations as Wyoming  and Colorado, where the
    environmental problems  are not so severe.

    It is important for the regulations established
    by the Federal government to be applicable
    nationwide so that pirating industry from  more
    protective states could be avoided.  It is also
    important for the Federal government to have
    its own  set of nationally applicable
    regulations so that it  can step into the
    enforcement area if the State falls down on the
    job.
    Other sections of the biI I
    briefly.
                               were discussed
The CounciI  of Governments proposed a program
to assess the nature and extent of the noise
problem, examine successful  existing and new
control techniques, and develop a noise control
ordinance, a noise control section of a land
use planning policy, and other programs.  This
was to take 3 years under an inter-disciplinary
Noise Control Advisory Committee and a noise
control engineer.  The total cost was to be
$130,810 of which 25% would come from the local
jurisdictions.  This was refused, but
suggestions were made for modification and
resubmi ssion.

Modifications included the  identification of
and reduction of hazardous and stress producing
noise  in the environment.  This program also
was to take 3 years and was subdivided into the
following tasks:   I) review literature, 2)
inventory current noise control activities,
3) inventory and rank major noise problems,
4) design noise  level and opinion surveys,
5) assist local  jurisdictions  in establishing
noise monitoring plans, 6) carry out public
education and information activities, 7)
conduct and analyze noise level and attitude
surveys, 8) rank-order noise problems, 9)
demonstrate specific control measures, 10)
develop noise control goals and objectives,
11) develop a set of noise control standards,
12) develop a model noise control ordinance,
13) develop a set of local noise control
policies, and 14) develop a set of action
programs and policies which can be undertaken
by non-local governmental agencies, by private
industry and organizations and by individual
citizens.  The total budget for this project
was $312,130.  This was rejected because
existing priorities allowed only new family
health care projects to be funded.

In the discussion which followed, it was
suggested that projects of this type would be
valuable and hopefully funding could eventually
be obtained.
    00-030

    Lentz, J. L.

    Metropolitan Washington Council of
    Governments, DC

    On:  REGIONAL PLANNING

    Witness  Statement
    Public Hearings on Noise Abatement and Control

    Washington, NOV 11,  1971
00-031

Kreml, F. M.

Automobile Manufacturers Association,
Washi ngton

On:  MOTOR VEHICLE NOISE ABATEMENT

Witness Statement
Public Hearings on Noise Abatement and Control

Washington, NOV 12, 1971
    A  discussion  of the problems encountered by a
    regional  association of  local governments
    when  it tried to obtain  funding  for a noise
    pollution  study  is presented.
Since the object of motor vehicle noise control
is to minimize annoyance to the public, the
Automobi le Manufacturers Association
commissioned a study to define what aspects of
motor vehicle are most annoying to people.  The
                                                         34

-------
                                                                                                         00-032
                                             EPA  HEARINGS
study was intended to establish guidelines to
needed areas of acoustical  improvement of
vehicles by manufacturers.

Some of the findings of the study are:

A. To reduce annoyance from motor vehicles most
rapidly, the noise from vehicles that cause
peaks above background levels should be
reduced, because it is the occasional noise
excursion that produces most complaints.

B. In the majority of cases where people
expressed annoyance at a specific vehicle noise
event, they felt that it was a situation the
driver could control, such as tire squal, hot
rodding, and similar operations.

C. Annoying noise sources are relatively close
to the auditor, e.g., 70? of the exposures
described as annoying within 100 feet of the
noise source.

D. Most people who express annoyance  indicate
that they are at home when the annoyance occurs
and  it  is generally in the evening.

As regards trucks, reduction of truck noise is
difficult because of the varied cnaracteristies
of the many sources on each vehicle.  Included
are exhaust, engine mechanical noise, air
intake, fan, transmission gears, tires and
other miscellaneous mechanical appurtenances.
Truck noise reduction is not a question of
putting on an improved muffler.  Muffling is
available for most trucks that effectively
eliminates exhaust noise as a consideration.
Tire noise is one of the most serious obstacles
to noise reduction at high speeds.  The  impact
on the  cost of transporting goods due to
vehicle modification to achieve stringent noise
levels  must be considered.  There may be an
increase in  initial equipment cost.   Sales of
trucks  and buses in the U. S. in 1970 amounted
to $4.8 billion; therefore, a }% increase in
cost wculd be $48 million that must be borne
by the  general public.  Since there are overall
weight  and length restrictions, vehicle
redesign which involves more space or increased
weight must do so at the cost of reduced cargo
capacity.

There would also be increased maintenance costs
because of more complex construction and
possible higher engine temperatures.

A strategy for reduction of noise annoyance is
presented in the following recommendations:

A. That, after thorough study of need, uniform
national standards be issued, with Federal
preemption and consideration of possible
conflict or trade-offs involving safety and
emissions standards.

B. That model legislation be developed for the
guidance of states and local  communities.

C. That effective enforcement procedures be
developed for state and local use.
D. That a long-range policy of motor vehicle
noise reduction be undertaken, taking
technological and economic feasibility into
account.

E. That substantial research efforts be
undertaken addressing the problems of:  tire
noise, technology of noise reduction, and
comparative economic impact of noise regulations
at various levels.
00-032

Larimore, H. T.

Construction Industry Manufacturers
Association, Chicago

On:  ECONOMIC FACTORS IN NOISE REDUCTION OF
     CONSTRUCTION EQUIPMENT

Witness Statement
Public Hearings on Noise Abatement and Control

Washington, NOV 12, 1971
Economic considerations of noise control in
construction machinery and industry
recommendations are presented.

Manufacturers of construction equipment admit
that many of their products are noisy.
Construction contractors have not been
motivated to engage in research for methods
to reduce noise and have not asked
manufacturers for quieter machines.  Thus, the
machinery manufacturers have developed
machines with increased productivity and lower
costs per unit of work output but not quieter.

There does not seem to be any imminent
technical breakthrough which can overcome the
problem of noise reduction.  Noise reduction
is a step-by-step process of analyzing each
noise producing element of a machine and
reducing it to a level which is below the dBA
level of other sound-producing components.
A 3 to 8 dBA reduction could be achieved at o
cost penalty of 10 to 24 percent over  • rei~iuc
of 5 years.

In various studies of environmental noise,
emphasis is primarily given to urban areas of
hign population density.  Demolition and
construction have in many of these locations
become almost a continuous process.  This is  in
contrast to highway and civil works
construction projects which, when completed,
are utilized for many years without new
projects being undertaken nearby.

A review of Bureau of Labor sta+isties
information reveals that there- is a substantial
difference in the expenditures for machinery
                                                     35

-------
00-033
                                                  EPA  HEARINGS
used for buildings (1 to 2% of project
cost) compared to tne machinery used on
highways (12?) and civil works — land
(20?).  It can easily be seen that
increases in machinery cost will  be reflected
to a much greater extent in project costs on
large rural  e^rthmoving jobs rather than on
building projects.   In other words, the cost/
effectiveness ratio of noise reduction is far
better in urban areas.  It would  therefore seem
appropriate  itvut current efforts  of n>i~<>
reduction on construction  equipment be
initially limited to urban site construction.

Government,    .o., Federal, State  and Local, is
the largest  , tistomer of the construction
industry.  In a Conference Board  article
entitled, "Economics of the Construction
Industry," the author states, "the share of
public construction  in total construction has
increased from 22 percent  in 1945 to 34 percent
in 1967.  it  is generally  believed that this
trend will  con} i nue",

On a trial  basis, it would appear that tie
Federal  Government,  through EPA,  is in the best
position to  initiate pilot cost studies.   On
certain  selected contracts, the Government
could specify maximum noise levels f-'r the
construction site.   Separate accounting could
be established to determine the costs, record
the techniques used to  limit noise radiation
and nore compliance  jitticuIties.

The Construction  Industry  Manufacturers
Association  (CIMA) points  out the following:

1) Member companies  are working on machine
noise redi.'-t ion r ^w  and are faced with the
necessi ly if pushing the threshold of The art
onto ne^ technological ground.

2) In response 1o CIMA f'e- forman.-o Standards
action,  vai ious standards  writirg bodies,
including SAE, are establishing uniform,
definitive and repeatdble  noise measurement
standards using dBA.  CIMA strongly opposes
reported current efforts by some noise
fechrr |->us  ro develop a different ^a'e,
which rould  seriously delay the noise abatement
effort" by causing several  years or noise
meacur foment  to be re-studied.

3) Member companies  generally do not oppose
r^: ilstic individual noise  lirpits for selected
!!,;< ii  •    • _* , ' «n under standardized conditions
and test .m  , "..•>•.  to  give  the repeatable  results
necessary ~or any c-:-r + i f ', jti on or  labeling
requ iiemen t.

4) Member companies  do  not oppose individual
macn'ne n^iss- output labeling, but do not think
'"tat  labeling requirements  should be applicable
to export snipments  until  such time as this may
become a requirement for a I I manufacturers on
ar  in-e. :ational  basis.
                                                                6) Members generally  believe that  national
                                                                noise  limit Standards could apply  to  selected
                                                                individual machines,  but control of the  total
                                                                job site noise  impact on the adjacent community
                                                                should be a State and/or Local Government
                                                                perogati ve.
                                                                00-033

                                                                Singer, A. A.

                                                                National Association  of Home Builders,
                                                                Philadelphia

                                                                On:  QUIET HOUSE PROGRAMS
                                                                Washington, NOV 9,  197!
                                                                The National Association of Home  Builders
                                                                (NAHB)  initiated efforts relating  to  noise  and
                                                                sound conditioning over  10 years  ago.   "Quiet
                                                                House"  programs were undertaken to familiarize
                                                                the consumer with welI-designed housing and to
                                                                determine the consumer's interest in  such
                                                                features.  A Residential Sound Conditioning
                                                                Manual  was developed to aid builders  in
                                                                providing cost-effective acoustical housing
                                                                env i ronments,

                                                                The NAH6 Research Foundation,  Inc.  has
                                                                continued research to measure  in-place
                                                                acoustical performance  in relation  to
                                                                construction, fne Dackground noise  levels,  and
                                                                the subjective response of the occupants.

                                                                Three studies have been made,  involving
                                                                measurements of airborne noise reduction,
                                                                impact  sound transmission with various  impact
                                                                sources, and the interior 'ivJ exterior
                                                                ambient noi-e levels.

                                                                Each  improvement to performance  level  increases
                                                                the cost of housing, and it is essential that
                                                                a balance between cost and performance  be
                                                                struck  so that j reasonable degree  of  quiet
                                                                is  provided wi khout ad'*e; -:c I y o^fectinq the
                                                                ability of all to  live  in decent  housing.

                                                                Several years nyo, an attempt wa:  made  to
                                                                develop special  construction techniques within
                                                                the house and special appliances  and  equipment
                                                                t"'""  Deduce the noise  level in the  house.  This
                                                                was offered as an optional extra  at a  cost  of
                                                                about $1000.  Many were  interested, but few
                                                                w i I  Iing to pay.  The buiIder then  sea Ied the
                                                                package down to $100, dealing only  with 1 he
                                                                areas of high noise  level and found many who
                                                                would  invest at this  level.   It was suggested
                                                                by  the  pan-°l that perhapr- with publicity or!
                                                                noise abatement1 more customers would  now be
                                                                willing to pay the $1000.  These  houses
                                                                rangecTin price from $20,000 to $40,000.
                                                         36

-------
                                                                                                         00-034
                                             EPA  HEARINGS
The most significant acoustical problems are
those between apartments, while noise sources
within the home or apartment are of less
concern and exterior noises are least
disturbing.  In apartment buildings, structure
borne noise transmission is the cause of most
disturbance, particularly impact noises are
bothersome since they are developed within
units and transmitted between units.  Airborne
noise is not as significant a problem as it was
10 to 20 years ago.  Electrical outlets in
party walls reduce the effectiveness of
otherwise satisfactory construction.  Revision
of the National Electrical  Code, and changes in
local enforcement practices are needed so that
electrical outlets are not required in party
walls.  The problems of economically isolating
sources of vibration from the building
structure need more attention.  Basic to
solution  is the need for development and
acceptance of measurement techniques and rating
methods.  The generally used ISO method of test
for  impact sound transmission and the Impact
Insulation Class rating system have given equal
ratings to floor construction which may vary
400?  in  loudness of transmitted footfall noise.
Only when improved methods of evaluation are
developed, can the development of practical
construction and installation techniques be
utilized to reduce the problem.  Similar
comments are applicable to problems of
transmitted plumbing and appliance noise.

In various studies, it was found that some
occupants are bothered by noise of kitchen and
other appliances when they are in another room.
Each of these noise sources is amenable to some
control, but most people are unwilling to pay
the  initial cost of "quieter" appliances or
modified  installation techniques.
Manufacturers should be encouraged to find more
cost-effective noise control techniques.
EPA and other governmental  agencies should
continue to encourage and support continuing
and coordinated research into the effects on
people, the development of techniques of
measurement and evaluation of noise, and the
development of practical and cost-effective
noise-control techniques.

Specifically, it is suggested that further
research is needed on the following subjects:
(1) Automobile and truck noise, including the
design of efficient yet quiet engines and
exhaust systems, truck and autombile tires, and
techniques of highway design to minimize its
effects upon the surrounding land use.
(2) Aircraft noise control, including the
development of quieter engines and aircraft use
patterns that minimize  intrusive noise.
(3) Structure-borne noise transmission,
including development of physical evaluation
techniques that permit rating products and
elements of dwellings and buildings in the
manner that people respond to them in use.
(4) More cost effective methods of reducing
appliance and fixture noise.
(5) Development of economical, practical, and
market acceptable window and door systems
specifically designed to minimize excessive
exterior noise intrusion.

Additionally, EPA might consider study of
enforceable  legislation and regulations which
local and state governmental bodies could use
to keep exterior noise and disturbance at
reasonable  levels.

Finally, EPA should encourage manufacturers
to label noise levels of appliances, equipment,
and related  items under a rational and
consistent rating system to inform consumers
so they may evaluate the equipment in relation
to noise.
Transportation noises such as those produced by
airplanes, trucks, automobiles and trains are
the primary source of exterior ambient noise.
Other noise sources include building
mechanical equipment, powered lawn and garden
equipment, power tools, snowmobiles and other
off-the-road vehicles.  Primary emphasis at
this time should be on further research and
development and voluntary efforts by producers
to reduce excessive noise levels.  However,
some legislative or regulatory measures might
be considered for this equipment provided
practically attainable performance levels are
estabIi shed.

One of the recent attempts to provide good
acoustical environment is HUD's establishment
of interim standards for evaluation of
community noise.  Because this is only a first
step and its effects have not been tested,
judgment must be reserved on its practicality
and on  the criteria themselves.   Government
planners at all  levels might be required to
consider the effect of new highways and
airports on the noise levels of existing or
planned  land uses prior to the decision to
impose  such facilities on the local
community.
00-034

Orski, C. K.

Organization for Economic Cooperation and
Development, Paris /France/
On:  TRAFFIC NOISE REDUCTION
                                EUROPE
Witness Statement
Public Hearings on Noise Abatement and Control

Washington, NOV 9, 1971
The Organization for Economic Cooperation and
Development (OECD)  has been conducting
investigations in the field of noise
abatement for a number of years as part of its
program of international  cooperation in the
field of environment.  The inclusion of noise
within the program has been a reflection of the
                                                    37

-------
00-035
                                                  EPA  HEARINGS
    growing  bel ief on the part of OECD member
    governments that noise, no less than some of
    the  more visible forms of pollution, represents
    a  real threat to the quality of the environment
    and  to the well-being of people.  Activities
    have ranged over such subjects as airport
    noise, sonic boom, and most recently, motor
    vehicles.  The reduction of noise levels in
    urban areas ranks high on the agenda of almost
    every OECD government.

    Within OECD, the concern about traffic noise
    has  led  to the creation of a special task
    force to develop guidelines for a model
    national  traffic noise abatement strategy.   The
    recommendations of the task force stress the
    necessity of vehicle noise emission standards
    and  effective enforcement machinery as a
    prerequisite to any substantial reductions in
    urban noise levels.  Such standards should be
    made progressively more stringent.

    Studies  within OECD concerning vehicle noise
    abatement are continuing in the context of a
    major inquiry, "The Impact of the Motor Vehicle
    on the Environment."  The aim of this project
    is to carry out a broad technology assessment
    of the motor vehicle in order to aid member
    governments in the formulation of comprehensive
    strategies toward the automobi le.

    The  United Kingdom's proposed 1973 noise
    emission limits for new vehicles are:
    passenger cars, 80 dBA; trucks (less than 200
    hp), 86  dBA; heavy trucks (more than 200 hp),
    89 dBA.   The limits recently agreed to by the
    Common Market countries are:   passenger cars,
    82 dBA;  trucks (over 3.5 tons), 89 dBA; heavy
    trucks (more than 200 hp),  91  dBA.
economic analysis of alternative vehicle
designs with reduced noise emission
characteristi cs.

In Sweden, Volvo has recently announced the
design of a new 320 hp diesel engine which is
6 dBA quieter that current engines of equal
horsepower.  The cost of the new engine is
estimated to be 5% higher than the cost of the
current engine.

Attention in Europe is principally focused on
reducing the noise output of the vehicle system
itself, while comparatively  little attention is
devoted to the problem of tire noise or
aerodynamic noise.  This is because in the
typical European  driving conditions the engine
exhause noise clearly predominates over the
latter.
00-035

Bricken, G.

Northrup Aircraft Company,
Los Angeles

On:  A COMPUTER BASED NOISE MONITORING SYSTEM

Witness Statement
Public Hearings on Noise Abatement and Control

Washington, NOV 10, 1971
     It  is a preliminary conclusion that reductions
     of  4 decibels or higher are envisageable, but
     probably only over the  longer  run since they
     would seem to require more fundamental changes
     in  the vehicle  system.  Nevertheless,  a British
     working group has recommended  a reduction in
     noise  limits down to 75 dBA for passenger cars
     and 80 dBA for  trucks, these proposed  standards
     to  take effect  in  I960.

     Following  is a  compendium of proposed  European
     legislation concerning vehicle noise emission
     standards:

     There  is a research program  in the United
     Kingdom with the objective of  developing a
     "quiet'' 80 dBA  diesel truck.   The project is
     looking at ways of minimizing  both body and
     tire noise as well as engine exhause system
     noi se.

     A private  company  in the U.  K. has announced
     the design of a diesel  engine  with noise
     emission  characteristics 4-9 dBA  lower than
     those  of  a conventional  diesel of the  same
     horsepower.   In Germany, the firm of Heinrich
     Gil let,  in cooperation  with  the Universities of
     Cologne  and  Essen,  is carrying out,  under the
     auspices  of  the German  Engineering Society and
     the Ministry  of Transport,  a technical  and
Systems, services and products designed to
bring about constructive solutions to
environmental  noise problems are discussed.
Little has been done in the past 10 years to
systimaticaIly apply known technology to
control  the presently controllable aspects of
jet aircraft, namely, operations.  Control of
flight paths, flight schedules, and persistent
noisy aircraft can bring about a decrease  in
airport community noise exposure.  Such
management of noise  is possible through the
use of modern data acquisition and data
processing techniques.  At the Orange County,
California, Airport an area-wide noise
monitoring system operates 24 hours a day.
The system, Ecolog  I, serves as a tool for the
airport to administer its program of managing
aircraft noise.  The system consists of 5
sensors, 3 located  in the normal departure
zone of the airport  in triangular array, and 2
located on the normal approach zone.  This
layout is used for evaluation of conformance to
noise abatement procedures, determination of
violation  levels, and assessment of community
noise exposures as prescribed  in the new Noise
Regulation for California Airports.  The system
consists of field stations with microphones
and electronics to convert sound levels for
transmission to a central  location.  At this
                                                         38

-------
                                                                                                         00-036
                                               EPA HEARINGS
location is a processor consisting of an input-
output buffer and computer for arranging and
manipulating the data for output to 2 display
devices.  The computer program provides a
multiplicity of easily adjusted variables to
assist the user in interpreting and extracting
needed information.  The airport obtains
single event readings for every aircraft
departing and arriving, single event
violations, automatic hourly energy averages,
and daily energy averages.  Continual
surveillance and analysis of computer produced
records allow the airport to obtain accurate
statistical records of noise levels and changes
in those levels.  Real time operation allows
the airport to respond immediately to community
complaints and to  immediately signal offending
aircraft of their violation condition.

Small systems can be acquired for $30,000 to
$50,000.   Larger systems can run as high as
$200,000.  Operating costs will run several
hundred dollars a month.

Only  3 such systems are  in operation  in the
United States.  Three problems stand  in the
way of wi der use.

First, the  lack of simple and convenient
standards  for measurement make it difficult to
develop equipment  for wide-scale application.

Secondly, there  is no clear-cut jurisdictional
authority  for noise control at airports.

Finally, there  is no real mechanism for
bringing citations against violators of  local
noise ordinances drawn in spite of the specter
of federal preemption.  Although the technology
for such noise abatement  is available today and
can be applied  in some cases at reasonable
cost, wider benefit will  only come about when
there are more definitive assignments of
responsibility, standardization of measurement
indexes and constructive  regulatory criteria.
be allocated until the last dollar spent on any
one commodity yields the same satisfaction to
society as the last dollai  spent on any other
commodity.  Given the fundamental fact of
scarcity of resources, less pollution must
mean fewer other goods and services.  Thus if
society wants less noire, clsaner air and less
polluted rivers and seas, it must realize that
the cost of less pollution is other goods am!
services foregone.  Society must order its
priorities.  What costs are we o^epared tr> pay
to enjoy less pollution?  For almost all  types
of pollution, costs rise disproportionately in
relation to the degree of non-pollution.   To
reduce the noise  level from the  local freeway,
the local  community must decide  if the real
costs, that is, other goods and services
foregone,  are worth the reduction in noise.
The reduction in noise will  be the marginal
benefit; the alternatives forego the marginal
cost.    If the former exceeds the latter,  the
project is worthwhile.  Unfortunately, with
many projects, the benefits are difficult to
measure.

The policy implications can be stated as
follows:  1) educate the public to understand
how pollution arises, the costs of pollution,
and fhe benefits of pollution; 2) establish
criteria for solving the pollution problem;
3) devote resources to the development of
measuring tools of pollution since successful
legislation will  require an ability to identify
pollution and degree of pollution; 4)
implementation of criteria to establish who
should pay to decrease pollution levels.   In
some cases, value judgments can be made
satisfactorily by designated officials who will
act in compliance with established criteria.
In other situations, however, a vore of the
people concerned is the most satisfactory method
to determine whether a noise polluted community
is in  economic equilibrium with other
conflicting demands of the populus.
00-036

Lumsden, K. G.

California Society of Professional
Eng i neers

On:  THE ECONOMICS OF NOISE POLLUTION

Witness Statement
Public Hearings on Noise Abatement and Control

Washington, NOV 9, 1971
00-037

Howe, J.  T.

Engine Manufacturers Association,
Chicago

On:  LEGAL ASPECTS OF NOISE CONTROL

Witness Statement
Public Hearings on Noise Abatement and Control

Washington, NOV 11, 1971
A discussion of the factors involved in the
economics of pollution with emphasis on noise
pollution is presented.  The general rule for
economic efficiency is that resources should
Three areas which provide the foundation for
any effective program to legally control noise
emissions are discussed.
                                                     39

-------
00-038
                                                  EPA  HEARINGS
    First, the need for objective standards which
    are achieved by a balancing process which takes
    into account the relative position of ah
    parties is an approach which has the capability
    of protecting the interests of a I I.  A review
    of arguments for and against uniform standards,
    and the test procedures and enforcement methods
    used +o enforce them is mandatory.

    Representative cases show that common law
    remedies '~a~ed upon subjective standards are
    not the ans'.v'?r.  In each situation, the case
    must be dec iced on its own merits  through a
    lengthy trial.

    Considering statuatory and regulatory
    approaches to the problem, it is noted that
    each s+ate, with the exception of  Alaska, has
    adopted some legislative or regulatory scheme
    for the legal control  of noise emissions from
    motor vehicles.  In 1969, the Department of
    Commerce's panel  on noise abatement examined
    stare and  local ordinances concerned with
    noise control.  This study noted that
    vehicular  noise control  in 32 states was
    limited to muffler requirements.  In
    seventeen  states and the District  of Columbia,
    the basis  of noise control was a subjective
    "disturbing the peace" appraoch with some
    objectivity occasionally interspersed by The
    regulation or statute setting specific no.se
    standards.  Other methods limiting  or
    prohibiting noise sources have been adopted in
    several  states.

    In  1969, only 3 states had specific noise
    standards, with regulations, imposing criminal
    penalties  for noise measured at prescribed
    distances  from noise sources.  Since 1969,
    however, many states, in response  to the need
    for some  legislation, have been enacting laws
    and regulations.  Standards applicable to
    engines should be balanced between the concerns
    for the environment with the benefits of
    technology.  The establishment of  fair and
    equitable  standards, with technological and
    economic  feasibility being a major factor to be
    considered on an increasing basis  as heaifh or
    medical considerations decrease will be to the
    benefit of all.  Such standards should tahe
    into consideration their effect on other
    environmental areas.

    The question of preemption was dominant  in
    these hearings.  Noise standards range  in some
    states from a  low of 74 to a high  of 90 dBA.
    There  is  a  lack of consistency  in  enforcement
    methods.  Some local governments have passed
    standards  but failed to adopt any enforcement
    procedure.  The Engine Manufacturers
    Association  (EMA) recognizes the need for
    effective  legal control of noise emissions and
    supports  uniform federal standards and
    enforcement procedures with federal preemption.
    Also, because of the variances  in test methods,
    a uniform procedure should be established under
    the aegis of one Federal government agency,
    preferably The Environmental Protection Agency.
    This agency,  in turn, should be given the
    authority to  delegate responsibility for
    enforcement of noise standards applicable to
engines to state and local governments which
adopt identical plans in accordance with the
uniform procedures established by the Federal
government.

Opponents to uniform standards, or preemption,
have expressed the concept that only the state
or local government can do the job effectively.
A thorough understanding of any law is always
essential for its effective enforcement.  By
permitting confusing and conflicting noise
standards, it would be impossible for the
public to understand and difficult for the
industry to respond and comply with such
standards.  It is also important that only one
agency within the Federal  government itself be
charged with the responsibility for the
promulgation of standards.
00-038

Bennin, R.

Bureau of Noise Abatement,
New York

On:  MUNICIPAL NOISE CONTROL

Witness Statement
Public Hearings on Noise Abatement and Control

Washington, NOV 11, 1971
The groundwork for a comprehensive urban noise
abatement program for New York City is
discussed.

With the help of HUD the first leg of a pilot
study has been completed.  When the study is
completed, a methodology for accurate and
comprehensive measurement of urban noise will
have been developed.

A Noise Control Code has been developed which
may become a model for the nation.  It  is
stronger and more comprehensive than any other
code in the country.  The Code attempts to deal
with urban noise pollution in 4 ways:  through
1) statutes on unnecessary noise modeled after
those already on the books; 2) specific decibel
limits on a number of noise sources, such as
air compressors, paving breakers, etc.; 3)
ambient noise quality zones for the different
communities of the city; and 4) and enforcement
section patterned after the recently passed Air
Code which will bring noise violations before
our Environmental Control Board instead of
criminal courts.

The Bureau of Noise Abatement currently handles
more than 400 complaints a month using moral
persuasion and community pressure since its
legal power is limited.
                                                         40

-------
                                                                                                00-038 (CONT.
                                             EPA  HEARINGS
Currently the Bureau has a staff of seven and
an operating budget of $100,000.  When the code
is passed, the need for a force of 15
inspectors, plus 3 equipment certification
officers, an acoustical engineer and 2
electronic technicians is predicted at a cost
of $250,000 and $500,000 for the study and
development program, make a total  budget of
about $800,000 for Fiscal Year  '72-'73.

The first priorities are the expansion of the
community noise survey and a traffic noise
survey.  Three additional projects are
underway; a construction noise survey, a study
to explore and assess alternatives to
automobile horn noise, and a siren noise study.

The city  is pressed to meet its most urgent
financial needs, and the Noise Bureau cannot
realize  its program fully within current
budgetary  limits.  A federal program of
development, establishment and maintenance
grants for local noise abatement programs is
urgently  needed.  A system of matching funds is
not satisfactory since the city cannot
guarantee to match  it.

Another area where federal assistance is
essential  is that of mass transit.  The subway
system in New York  is old and noisy.  The City
does not have and is not going to have the
estimated millions of dollars needed for a
comprehensive program of subway noise
abatement.  A program of federal noise
abatement grants for mass transit, either out
of an expanded Office of Noise Abatement or out
of the Department of Transportation is needed.

In addition to establishing a system of grants
for local noise abatement programs, there are
a number of ways in which the federal
government can play a powerful role in noise
abatement.  First, the government should
promote the use of quieter equipment by
incorporating noise specifications into all of
its vast purchasing programs.  Second, all
federally contracted construction projects
should be  required to meet specific noise
standards.  Third, the federal government
should make funds available for demonstration
projects to promote advancement of noise
abatement technology.  Last, more research is
needed in the area of health effects of noise.

The Federal government must also play a role
in jurisdiction.  Some of the major sources of
noise pollution in urban areas are not
susceptible of solution on the municipal  level.
The most obvious is aircraft noise.  The noise
problem created in urban areas by motor
vehicles  illustrates an  important aspect of the
Federal noise abatement role.  New York City is
attempting to regulate this source in its
Noise Control Code.  The most effective way to
stop noise is at the source and Federal  limits
on a I I  classes of motor vehicles would be
welcome.   It  is essential that the Federal
government set specific noise limits wherever
possible, but states and municipalities must
be left free to set more stringent standards
if necessary.  Noise pollution is ultimately a
I oca I  p rob I em.

Noise in our cities can no longer be ignored.
It is a problem ranging in seriousness with
pollution of air and water.   It must be
attacked vigorously by a I I  levels of
government,  by industry, and by the individual
citi zen.
                                                    41

-------
                            ABSTRACTS
             NOISE SUBJECT FIELD AND SCOPE NOTES
As an aid to the reader with specialized interests,  abstracts of journal
articles,  reports and other sources have been grouped by subject area.
The twelve categories used are listed and briefly described below.
However, there is often considerable  overlap, and  related categories,
as well as the subject index,  should also be consulted.

1.    EMISSION AND SUPPRESSION RESEARCH AND DEVELOPMENT

      Phenomenology of noise generation, transmission  and suppression,
      including experimental data and theoretical studies.

2.    PHYSIOLOGICAL EFFECTS

      Aural and non-aural effects:  e. g. ,  hearing loss, circulatory and
      cardio-vascular effects, sensory perception,  neural effects, etc.

3.    PSYCHOLOGICAL AND SOCIOLOGICAL EFFECTS

      Effect of noise on sleep and work patterns and other human
      activities; personal attitudes toward noise; effect of noise on
      learning,  convalescence,  etc.

4.    ECONOMIC ASPECTS

      Costs of noise abatement  and control; costs of non-abated noise,
      impact on trade  both domestic and foreign.

5.    BUILDING ACOUSTICS AND NOISE  CONTROL

      Use of construction materials and their installation,  such as
      techniques for isolating and decoupling electrical outlets, plumbing
      and air flow ducts  from partitions; reduction  of impact and airborne
      noise transmission.

6.    NOISE MEASUREMENT

      Units, instrumentation, techniques, scales, weighting networks,
      recording and monitoring systems,  data processing systems.
                                  42

-------
7.     PLANNING, DESIGN AND ARCHITECTURAL SITING

      City planning, industrial plant layout and design, land use,  airport
      and highway siting, land development,  zoning.

8.     LEGISLATION,  STANDARDS,  LEGAL PRECEDENTS

      Laws,  codes,  zoning ordinances, statutes, standing of parties,
      jurisdiction of courts, court's decisions, etc.

9.     ENFORCEMENT

      Enforcement techniques and experience,  including training,  equip-
      ment costs, staffing.

10.   PROGRAM, PLANNING,  AND BUDGET

      Federal, state,  and local policy decisions; budget information;
      program status, program descriptions.

11.   NOISE  MEASUREMENT DATA

      Noise emissions generated by equipment or activities; attenuation
      levels for particular materials,  time histories, octave band
      analysis.

12.   EDUCATIONAL AND GENERAL

      Textbooks, university curricula,  general education articles,  mass
      media coverage, popular brochures, and other popular awareness
      materials.
                                  43

-------
01-001
                                           EMISSIONS SUPPRESSION
    01-001

    Flanagan, W.

    Automotive Engineering

    RECENT STUDIES GIVE UNIFIED PICTURE OF TIRE
    NOISE

    Automotive Engineering

    Vol 80 No 4:15-19, 1971
    Data establishing truck tires as a noise
    source are presented.  Tires fall into three
    clearly defined categories as noise producers:
    pocket re-tread, cross-bar, and circumferential
    rib.  Loudest are older recapped tires,
    particularly the pocket retread.  Lateral
    elements of cross lug tires may wear into
    pockets and produce noise the same way, but most
    noise is generated by the gripping and releasing
    action of the tread elements during traction.
    The quietest tires are rib designs.

    Rankings within tire noise categories may
    shift as the road surface changes from concrete
    to asphalt.  Sound levels rise with increasing
    speed on all tires, but at slightly different
    rates.  The National  Bureau of Standards (NBS)
    reports an average 3 dBA increase per 10 mph.
    At  lower speeds, down to 20 mph, total  truck
    noise changes faster, 5-10 dBA per 10 mph.

    NBS reports that loudness (peak dBA reading)
    produced by most tires rises 3-5 dBA when
    the tire is half used.  Some tire types make
    more noise fully-worn than when half-worn.
    NBS data indicate that the difference in peak
    sound level between new and ha If-worn states
    is greater on concrete than on asphalt,
    depending on the frictional properties of the
    road.  Theories on the effect of wear seem
    to agree that pressure distribution in the
    contract patch may be an important variable.
    Most tires wear first in the middle, trans-
    ferring weight to the outer edges of the
    patch.

    Higher forces on tread elements make for more
    noise, regardless of where the force comes
    from.  Sound level differences due to load  in
    the NBS data are only 1-3 dBA for rib tires,
    but increase significantly for cross bar
    (6-8 dB) and pocket retread tires (4-8 dB).
    Inflation pressure has no definite effect.

    The tire industry has not subscribed to dBA
    exclusively because of its deficiency in
    measuring tonality.  Subjective comparisons
    point to tonality and persistence as major
    factors of annoyance.

    High hysteresis rubbers could reduce noise
    by damping the snap actions of tread elements,
    but the energy would go  into heat  instead of
    sound.  Because of the thickness and low
    thermal conductivity of truck tires, heat
    generation creates high temperatures and has a
    deleterious  influence on durability and safety.
01-002

Fosca, V.
Biborosch, L.
Popped, N.

Technisches  Institut, Fakultaet Fuer Bauwesen,
Jassy /Rumania/

Technische Hochschule in Jassy, Str. Karl Marx
No. 38,  lasi, R. S. Romania

INVESTIGATION OF SOME TRAFFIC NOISE
RELATIONSHIPS

Untersuchung Einiger
StrassenIaermabhaengigkeiten

Laermbekaempfung

No 2/3:46-48, 1970
Investigations of traffic noise in Jassy,
Rumania, were conducted.  The results showed
that the noise levels exceeded regulations
even for the  low density traffic.  Measurements
were taken at 7 to 10 m from vehicles travelling
at 30-50 Km/h.  The results were as follows:
Type of Veh icle
Buses with diesel engine
Trucks with internal
   combustion engine
Automobi les
Street-cars
Level  in dBA
91-93

81-84
80-82
82-85
The measurements were conducted on 3 different
types of main arteries, those with greenery,
close, and distant house-fronts.  The first
group had tall trees on the side-walk area
between the street and houses, group I I
had some lawn and sparse shrubery and group
III had closely congested houses and narrower
streets.

Group I  and  II showed a small variance of 6 dB
from group III.  Frequencies play an important
part especially in the ratio of the echo time.

In order to attain considerable noise reduction
in the  lowest frequency range screening by
means of walls or types of building can be
used.
                                                         44

-------
                                                                                                         01-003
                                       EMISSIONS SUPPRESSION
01-003

Rainey,  J .  T.

Carrier Corp., Syracuse, NY

Research Division, Zip 13201

EVALUATION  OF NOISE CONTROL TECHNIQUES FOR
QUIETING PLATE FIN PRESSES

Syracuse, Carrier, 21 p.
Methods for quieting a plate fin press when
machine enclosures prove to be infeasible are
examined.

The die areas were found to be the greatest
contribufors to the noise generated by plate fin
presses.  It was also established that most
of this noise was generated by metal  to metal
contact of the traveling pads and stationary
pad keepers.

A reduction of 3-4 dBA was achieved by imposing
a resilient material between the normally metal
to metal contact areas of the traveling
stripper pads and the stationary pad keepers.
The application of the resilient material
using urethane rubber requires less than a work-
day for each machine, has been shown to  last
for at  least a year, and does not affect
the production rate of the machine.

When all of the presses are running the noise
levels produced at the operator's  locations can
be expected to be about 3 dBA above the noise
level produced by a single press.  The noise
reduction achieved by using impact strips
may not, however, be enough to meet the 8 hour
90 dBA  I imit set by the Federal  Occupational
Safety and Health Act.  Preliminary tests of
an additional noise reduction modification,
namely that of splitting the traveling pads,
show promise for reducing the noise even
further; however, the specific benefits of
this modification must await further testing.
01-004

Wiedefeld,  J.

CONSTRUCTION TECHNOLOGY FOR ABATEMENT OF
AVIATION NOISE IN THE RESIDENTIAL AREAS
AROUND THE  DUESSELDORF AIRPORT.  PART 2

Bautechnische Massnahmen zur Bekaempfung
des Fluglaerms in den Besiedelten Wohngebieten
des Flughafens Duesseldorf. Teil  2

Kampf Dem Laerm

Vol 18 No 1:13-17, 1971
Part 2 of this article describes the tech'iicnl
measures for the abatemenr of aviation noise
in a Catholic elementary schoci  GuesseIdorf-
Lohhausen, in the vicinity of The Duesseldort
Ai rport.

Acoustical measurement taken by  the Max-Planck
Institute gave values of 105 dB  ana 110  dB
for jet aircraft.

The noise level   in the classrooms facing the
west and with closed windows was 89-98 dB,
Double box-windows were installed and quality
materials were used in ("he construction.
After the windows were installed the sound
level  was lowered at least 15 dB.

A 2 meter wide and 1.40 meter deep outer
chamber (ante-room) consisting of bricks and
mineral fiber tiles was constructed on both
sides of tne entrance with a soffit over ~ne
door.   A double  layered door consisting  o^
50 mm thick metal frame and d 12 mm triicK
wired plate glass, the inner door is
similarly constructed,  was installer1.

Because of the frequency of starting and
landing jet planes the east and  north side
of the corridors were reinforced with an
outer sound-absorbing wall.

With these new sound-absorbing me=ns the
instruction  in the classrooms could be
carried out without any disturbance or
i nterrupt ion.
Bolt, Beranek, and Newman, Inc.,
Cambridge, MA

NOISE OF PILE DRIVING EQUIPMENT

At:  Acoustical  Society of America Meeting,
Washington, APR 20-22, 1971

Cambridge, BolT Beranek,  and Newman, 1971, 9p.
The problems of measurement analysis and
evaluation of pile driving equipment is
d iscussed.

Impact hammers and vibratory drivers comprise
the two main categories of pile drivers.
Impact hammers have either steam pressure or
diesel engines, and noise is generated by both
the power source and by the impact of the hammer
and pile.
                                                     45

-------
01-006
                                            EMISSIONS SUPPRESSION
    The vioratory hammers are either low frequency
    (30 Hz)  with electric engines, or high frequency
    (50-150  Hz), powered by two unmuffled gas
    engines.

    Comparisons of noise spectra generated by 3
    types  ot  pile drivers are presented in Figure
    1.   Total  sound energy varies with blows per
    minute.
    Comparison of Noise Levels of Different Pile Drivers
       A STEAM. 15" PIPE CAPPED
         BOSTON CITY HOSPITAL
       O DIESEL'14" PIPE HOLLOW
         PROVIDENCE CIVIC CENTER
       O SONIC. 14" PIPE HOLLOW
         HARVARD CEO-CHEMICAL
                                             STEAM
                                             DIESEL
ALL PEAK LEVELS
  (SLOW SCALE)
NORMALIZED TO 50'
       3L5
            63   125  230   500  1000 2000 4000 8000 16,000 3I.5OO
             OCTAVE BAND CENTER FREQUENCIES IN Hz
    Diesels  are best suited for hard soils, whereas
    steam hammers are best used on soft soils.
    Diesels,  diesel  crews, and fuel are more
    economical  than steam.  A sonic driver costs
    about 2-2i  times as much as steam equipment.

    Much more research is necessary in the field of
    construction equipment such as pile drivers;
    presently the state of economy dictates the
    choice of equipment.
    01-006

    Priede T.

    Southampton  Univ.  /England/

    ROAD  TRAFFIC NOISE-ITS  ORIGINS AND CONTROL

    In: Janson,  P.  6., Conferences in Connection
    with  the  International  Air Pollution Control
    and Noise  Abatement Exhibition, Joenkoeping,
    Sweden,  SEPT 1-6,  1971

    Joenkoeping, Sweden,  1971, 525p.  (p. 7:12-7:30)
    A  comprehensive study of the relation between
    subjective rating  of noise emitted by motor
    vehicles and the objective measurements with
    a  sound  level  meter has been made.  Subjects
    were  asked to rate the noises which were
presented to them according  to a  six-point
rating scale by verbal  description.   It can be
concluded that a  level  close to 80  dBA fairly
represents the demacration  lire between
"acceptable" and "noisy"  for most vehicles

The range of measured dBA  levels  for various
types of vehicles were:   heavy commercial
vehicles, 88-92;  light  commercial vehicles,
79-91; cars 77-91.  The  legislated  standards
in the United Kingdom for these vehicles are
89, 85 and 84 respectively.  Tests  indicate
that truck noise  is predominantly controlled
by the power unit.  This  increase of noise
is 11 dBA per doubling  the speed.   In
gasoline cars a doubling of  speed results  in
an increase of 15 dBA.

It can be concluded that noise is generally
independent of the volume of work done per
unit time or horsepower.  The  main  criteria
which determines the noise  is  the operational
speed or how short the  time  interval  is
within the operation of one cycle of events
is being performed by the machine.

Transmission noise ranges from 75-85 dBA
and seems dependent upon engine vibration.
Road conditions have greatest  effect on tire
noise, an 8-10 dBA increase  in noise is
noticed  if the road surface  is wet  and a 3-5
dBA increase if it is coarse rather than
smooth.

A quieter vehicle can only be  achieved by
close co-operation between the vehicle and
engine designer and the following essential
aims should be observed.  First,  design a
vehicle giving adequate attenuation  of
the engine noise.   Also appropriate  choice
of engine design parameters  is necessary
including:
1)  limitation of  the maximum  engine rated
speed;
2)  limitation of  engine cylinder capacity,
3)  increase of engine  load even  to  four
times the values at present used,
and, finally, a quieter engine structure.
Methods of rating  noise and noise as a
function of engine speed are also discussed.
                            01-007

                            Warren, C. H.

                            Royal Aircraft  Establishment,
                            Farnborough  /England/

                            Structures Dept.

                            SONIC BOOM EXPOSURE  EFFECTS  I.2:   THE SONIC BOOM
                            GENERATION AND  PROPAGATION

                            Journal of Sound  and Vibration

                            Vol 20 No 4:484-497, 1972
                                                        46

-------
                                                                                                          01-008
                                        EMISSIONS SUPPRESSION
A description  is given of the technical
aspects of the generation and propagation
of sonic booms in order to provide the
background for an understanding of their
effects on animate and inanimate objects.

Any aircraft  in flight creates a pressure
field  in the  surrounding air.  At
supersonic flight speeds the pressure
disturbances  are concentrated in waves.
The pressure  disturbances  in these waves
decrease at roughly the  inverse first power
of the distance from the aircraft.  Because
of this  lower intensity decrease with
distance as compared to subsonic aircraft, the
pressure disturbances made by supersonic
aircraft are  experienced at  larger distances
from the aircraft.  Moreover, the sharp
variations in pressure make  the disturbances
audible  as the sonic boom.
Field work was carried out from August to
early October, 1970,  in eastern Ontario &
western Quebec.
01-008

Myles, D. V.
Hirvonen, R.
Embleton, T. F.

National Research CounciI of Canada,
Ottawa /Ontario/

AN ACOUSTICAL STUDY OF MACHINERY ON LOGGING
OPERATIONS  IN EASTERN CANADA

Ontario, National Research Council of Canada,
APR,  1971,  41 p.
A survey concerning noise from  logging
machinery and the effect of the forest in
reducing that noise was carried out following a
meeting held in Ottawa in April, 1970, that was
attended by representatives from the Canadian
Forestry Service, National Research Council,
Ontario Department of Lands and Forests, Pulp
and Paper Research Institute of Canada, Ontario
Forest  Industries Association, and the
Canadian Pulp and Paper Association.

The survey had the twofold purpose ofobtaining
a statistical  picture of:  1) the noise
produced from typical  logging operations and
from the different types of machines on them;
and 2) the influence of normal forest conditions
on the propagation & attenuation of sound from
logging operations.

This approach  was expected to produce results
from which preliminary conditions could be drawn
concerning:   1) the noise characteristics of
common logging machinery; 2) the risk of hearing
damage to machine operators; and 3) the
propagation of sound in the forest with respect
to other forest users.
01-009

SOUND-DEADENING  IN SOIL PIPE SYSTEMS

Compressed Air Magazine

Vol 76 No 11:18, 1971
A 2-year study conducted by Polysonics
Acoustical Engineers demonstrated neoprene
synthetic rubber's role in alleviating noise
in soil pipe systems.  Random vibration.
sources were set up and neoprene was applied
in various axes to the pipe being measured.
Measurements of cumulative vibration drops
over a large number of joints, as well as the
per-joint reduction, were made.  Polysonics
determined that in a cast iron soil  pipe
system, use of neoprene gaskets provides a
positive reduction in vibration, and hence
noise, at each joint.  (Soil  pipe systems
made of cast iron are quietest because of
thei r heavy mass.)

A neoprene compression gasket was found to
provide vibration drops as high as 20 dB per
joint at the higher frequencies.  A  Cl  No-Hub
neoprene gasket with stainless steel coupling
provides vibration drops of as much  as 11 dB
per joint at higher frequences.  Both types
prevent direct metaI-to-metal  contact at joints.

Field tests conducted in Washington, DC
high-rises showed even greater vibration  drops
per joint than in the lab tests.
                                                    47

-------
01-010
                                        EMISSION & SUPPRESSION
    01-010

    Goncharenko, V. P.

    Steklotarno-lzolyatornyy Zavod, Ordzhonikidze
    /USSR/

    ON THE REDUCTION OF AUTOMOBILE AND TRACTOR NOISE

    K Voprosu o Snizhenfi Shuma Automobiley i
    Traktorov

    Gigiyena Truda i  Professional'nyye Zabolevaniya

    Vol  14 No 1:46-47, 1971
01-011

Bobin, Ye. V.

Leningradskiy  Institut Inzhenerov
Zheleznodorozhnogo Transporta im. V.  N.
Obraztsova, Leningrad /USSR/

NOISE REDUCTION FOR RAILWAY TRAFFIC AND
RHEOSTAT TESTS OF DIESEL LOCOMOTIVES

0 Snizhenii Shuma pri Dvizhenii  Poyezdov i
Reostatnykh Ispytaniyakh Teplovozov

Vol  34 No  1:94-97, 1969
    Soviet sound pressure meters with frequency
    analyzers were employed to measure noise
    levels at a 7 meter distance emitted from
    vehicles travelling at speeds of 19 to 25 mph.
    The range of readings was 74 to 109 dB.
    The total sound pressure level  (SPL)
    for trucks with frequency range predominante ly
    351-800 Hz, was 89-107 dB,  while for light
    weight cars it was 74-103 dB with an average of
    88 dB.  The ''Belorus" tractor ranged from
    78-101 dB, while heavier tractors and
    bulldozers produced readings of 95-105 dB at
    frequencies above 800 Hz.  In all  cases  the
    existing standards were exceeded.   Vehicle
    interior readings were 70-80 dB (800 Hz) at
    rest and 76-89 dB in motion.

    To reduce automobile and tractor noise,
    dynamic balancing is required for the engine,
    the gear box, the Cardan shafts, the fan,
    the divided axle, the wheels and the tires.
    Elastomettalic coatings made of perforated
    materials must be more widely introduced, along
    with antivibration coatings and soundproofing
    shields.  Damping devices must be improved
    and put into wide use.  Impacting metal  shafts,
    gears, etc. need to be replaced by plastics;
    hydraulic and pneumatic suspensions should
    phase out springs; straight-toothed gears should
    be replaced with spiral helical  or worm gears.
    Manufacturing tolerances must be cut to a
    minimum to reduce joint clearances and
    prevent frictional noise.  The bearing surfaces
    of joints must be fully protected by lubricants
    and rocker bearings must be replaced by
    slide bearings and noise and vibration
    insulating coverings.  Power transmission
    can be damped by flexible couplings and housing
    openings for passage of shafts, etc. should
    be equipped with mufflers in the form of pipes
    whose interior is faced with sound-absorbent
    materia Is.
Soviet regulations prescribe the distances that
residential  areas must be located from
railway tracks, depots and rheostat-test areas.
Recent measurements have shown that the
standards for residential noise in the vicinity
of such railway facilities are universally
violated, although distances in many cases are
in keeping with regulations.

Realistically, means must be found to attenuate
the noise, both by insulation at the source
and by screening along the sound path.  The
protective effect of brick shields built in
Lvov  is cited.

The brick shield was built 15 meters high
18 meters from the railroad tracks and 72
meters from the housing  it was to shield.
It reduced the noise  levels in the housing
area  by 20 dB, or a factor of four in terms
of subjective  loudness, enabling the
regulations to be met.
01-012

Doak, P. E.
May, D. N.

Southampton Univ. /England/

Institute of Sound & Vibration Research,
Southampton S09 5NH

LETTER TO THE EDITOR: EFFECTS OF LOUVRES ON
THE NOISE OF AN AXIAL FLOW FAN

Journal of Sound and Vibration

Vol 15 No 3:421-424, 1971
                                                                The  effect  on  the  sound  field  of  axial  flow
                                                                fans of  louvers  positioned  across their
                                                                intakes  was studies  in  light of  design  of
                                                                lift fans  for  vertical take-off  aircraft
                                                                and  ventilation  systems.
                                                         48

-------
EMISSIONS SUPPRESSION
                                                                     01-013
 A rig configuration was chosen which was
 typical  ot  ire levels wiit  and without
 tr.t, •  '•,[-.

 Measurements were made of overall  sound pressure
 level  for  rotor speeds ot 6000 and 12000 rev/min
 at ten  degree intervals of microphone position
 between  -90 degrees and +30 degrees.  This
 wj; performed for ten lonve;  angles from
   U-  rr-pc  "I  * 9>"'  ^onrpe-
 •j vjt ^r^eb  i., y^  oCgrc-L-b.

/" compjiib^n of tne  airflow measurements  and
and tne °es.ri+s  iridi  a^oo  Mat the  increase  in
sound pi-assure  level  whori  the  louvers  were
 tilted about 40 degrees  occurred when  the
 louvers begfii  t,-  navr  •,  s|v  lirig t,ffe^t on  the
flow to rhc  rotor.   Tri   --'fe-.t  bt;came
more marked  as the  icuv< r  angle  increased  unti I
a point was  reached  .-'  -   jt 65  degrees where
the opposing effects  ' "  reduced  mean  flow  and
acoustic blockage  bec.!.i»e effectively  egual,
and beyond 65  degrees  *"e  cmount of  noise
r art i a  ted f rorr  'he  i n ' ^ .' dec. rfectscd .

The overall   noise  fielj  v^as found to  be
roughly non~directionat  for all  louver
angles, but  the distr.'.,i  on  in  angle  of  the
radiated noise at  the  i >, i i d-octave  band
containing the blade  "ossage frequency was
found  to deviate  i r<  -  ~ ather  irreoular
manner.
                       01-013

                       Swetnam, G. F.
                       Willingham, F. L.

                       MITRh Corp., McLean,  VA

                       1820 Do I ley Madison Blvd.,
                       Zip 22101

                       EVALUATION OF CITY TRANSIT BUS  "EIP"  KITS  TO
                       REDUCE ENGINE SMOKE,  ODOR, NOXIOUS  EMISSIONS
                       AND NOISE
                       The General Motors' Environmental  Improvement
                       Program  (EIP) re'ruiit was  desirineo  to  be
                       installed c r CM  city  transit  bus---, vjit:1 H «o
                       cycle diest-,1 engines  for  the  reduction  ot  lit
                       emissions and nois-?.   Field testing  ha-a
                       shown that EIP kiis,  propertlv  installaJ and
                       maintained, reduce visible  smoke,  odor,
                       noxious emissions or  hyar ^carbon?  a'ld
                       carbon monoxide  and (slightly1'  noise
                       levels  inside the uus.  Mo/j^v,-r,  e>i,, , ~*(
                       noise was not reduced  and eve.1  in;'eased
                       under certain circumstances.  Better noise
                       reduction performance  might ne  jttain^t, with
                       no worsening of  other  performance ^aramelers,
                       if certain kit components were  redesigned.

                       The kit cons i s ted ot:  ( 1 )   ,e ^ r  1 oN ' JL-
                       injectors, (2) vertical,  aspirated exhaust
                       stack,  (3) muffled air  induction  system,  (4)
                       energy abso-bing engine mount-,  (:•)  mutr'i-
                       incorporai ,.ig a  ^.atat/fir reacior, as  we > ' as
                       chariges  in operation:  revised f jel  injector
                       timing, higher t ransmi . j ior>  t.Mt speed
                       setting, ana use ot Number  !  t  die csiesu1
                       fuel.

                       Bus noise  is transmitted  to the inferior
                       through engine irountings  and  various ducts.
                       Exterior noise is radiated  from exhaust and
                       intake openirg=, the  air  conditioner arid
                       the cooling tan.  The  EIP kit's improved
                       motor mounts and air  intake muffling reduced
                       inferior noise levels  slightly.   The mounts
                       used  ji-,01 |iriu-:i   rubber insul riio', ' t f ween  the
                       eno/ '  cradle ^nd The  coach ohas. 's,
                       observations showed ^ha'  sorut- of  the i
                       had soon deteriorated  VH rn  s&r"v «'\. i^
                       suggesting that  redesign  may  be  --.'G.I
                       One rxd^-r. rx:^rior roise i^as 'l 't  r-.Uu.'f-d  /jas
                       that the exriju?t stack and ..araiylic  muffler
                       treatments were chiefly aimeo a~ abating
                       ail po i 1 u i  i - .n .  Since  ^he ra'ulytiC rnufiler
                       was not par;icuiarl/ effective toward  that
                       purpose,  it might well be replaced with a
                       muffler thaT  was rror-e effective acoustically.
                       The o+her  reasr;n rhaf extei ior noise  Tended
                       to  increase was the higher shift speeds
                       needed to  reduce the smoke produced at shift
                       points.
                49

-------
01-014
                                         EMISSIONS SUPPRESSION
    GM  first  assembled  the  kits  in  late 1969.
    Of  53,000 transit buses  in the  national
    fleet, the majority  are  of 6MV  manufacture.
    The EIP kit or  at  least  its  most  effective
    component,  the  LSN  injector,  could  be fitted
    in  its entirety  to  the 24,000 "new  look"
    buses produced  since 1959.   Buses fitted  with
    EIP kits  were tested in  San  Francisco,  San
    Antonio,  and Washington,  DC,  during
    1970-71.

    A bus presently  in  service could  be fitted
    with an EIP kit  for  about $2650,  parts  and
    labor.  Including the kit at  the  factory  in  a
    new bus would cost  about $500-550.
    01-014

    Myles, D.  V.
    Hirvonen,  R.
    Embleton,  T.  F.

    National Research  Council  of  Canada,
    Ottawa /Ontario/

    ON:  NOISE MEASUREMENTS  OF LOGGING  MACHINERY
    IN THE FOREST

    In:  Myles, D., An Acoustical  Study of  Machinery
    on Logging Operations  in  Eastern  Canada

    Ontario, National  Research Council  of Canada
    APR,  1971  41p.  (p.  17-41)
    Noise measurements  of  logging  machinery  in  the
    forest and  a  few  suggestions to  reduce noise
    that  is  recreationally  intrusive are  presented.

    Sound  level  readings were  taken  of  about 130
    different  logging operation machines.   Skidder's
    and chain  saws  are  the  most common  noise
    sources.   Readings  were taken  at the  operator's
    ear for  both  loaded and empty  machines at 15 and
    50 feet  for eight frequency bands (63 to 8,000
    Hz).

    The maximum distances at which the  noise from
     logging  operation was audible  were  also
    determined  for  several  sites at  upwind,  cross
    wind  and downwind.  Temperature, humidity,  wind
    speed and  direction were noted at all  times,
    notes on topography and forest cover  were kept,
    and ambient noise levels were  measured as often
    as practicable,  using Bruel and  Kjaer portable
    sound  leve-l  meters.

    The number  of machines  producing various
    sound  levels  is  illustrated  for  all  skidders and
    chainsaws,  by histograms of the  measurements
    taken  in dBA  (Fig.  1) and  dBC  (Fig  2).  For sound
    energy following  the  inverse square law
    the  levels  should be  10dB  lower  at  50 ft
    than  15  ft, but skidder noise  decreases  by only
6 dB because of the machine's size.  On  rough
terrain, skidders produced more noise when  empty
than when full.  For the noisiest  \Q% of  fhe
chain-saw operations the sound  levels ranged
115-119 dBA.  There was great variation
between chain saws of the same make  and  model.
                                0     10
                            Scale of No. of Machines
      120
                                                                       110
                                                                       90
      80
      70S..
        "Skidd.
                                       Sawi
        at operator's ear    at \5 feet     at 50 feet

    FIGURE 1.
                               0      10
                           Scale of No. of Machines
                                                                       110
     100
      90
      80
      70
        Skidde
              Saws    Skiddtrs
                                       Saws
         at operator's ear   at 15 feet      at 50 feet

   FIGURE 2.
Noise spectra measured at 50 feet were  averaged
and plotted for chain saws, skidders,  loaders
and logalls (Fig. 3)  According to the  inverse-
square law, the noise levels should  decrease
22.5 dB between 50 feet and 10 chains  (660
feet).  However, the decrease was actually  about
32 dB in the  low frequency octave bands and
42 dB in the high frequency octave bands.
This additional reduction is probably due
to forest absorption and the average of many
different atmospheric conditions.
                                                          50

-------
                                     EMISSIONS SUPPRESSION
                                                                                                         01-015
        Companion of voriom moenmct
          01 M II
               63   125   350  500  1000  2000  4000  8000
                     FREQUENCY-Hi
01-015

Myles, D. V.
Hi rvonen, R.
Embleton, T. F.

National  Research CounciI  of Canada,
Ottawa /Ontario/

PROPAGATION OF SOUND WAVES IN FORESTS

In:  Myles, D., An Acoustical Study of
Machinery on Logging Operations in
Eastern Canada

Ontario,  National Research Council of Canada
APR, 1971, 41p.  (p. 2-17)
The human ear can certainly distinguish
machinery noise from background noise in the
forest, even when the machinery noise is less
than the ambient background noise.   For this
reason a human measured (rather than machine
measured) approach was applied to the
problem of intrusiveness of noise on a
recreational  use of the forest.  In the average
situation, the chain saw noise could be
heard to a distance of 115 chains (1.43 miles).
Skidder noise could be heard to a distance of
116 chains (1.45 miles).

Particular situations can differ markedly from
the average.  On s1 i I I mornings  logging
operations could be clearly heard for distances
of over 2 mi les.  Noise from a skidder working
across a bay registered 58 dBA at a distance
of 0.9 miles.  On some occasions in hilly
country, noise was not heard much beyond 0.5
mile, but from a hill top a slasher was heard
2.25 miles away.  On a windless, misty day,
chain saws could be heard at 2.25 miles in
fairly flat country, but  in a 5 mph breeze
the same operation was inaudible beyond 0.7
mile upw i nd .

When considering the propagation of sound over
long distances, any reduction at the noise
source  would help reduce the distance that
such noise would travel.  A 6 dB reduction can
be obtained by muffling and will reduce by 40%
the distance at which it can be heard.  Further
improvements would require an attack on
engine noises other than exhaust.

To prevent intrusiveness of noise to campers,
it is concluded that  logging operations should
not be permitted closer than one mile from the
location being used.
The propagation of sound waves in forests is
investigated as acoustical background to a
Canadian survey on noise from logging
equipment and the effect of the forest in
reducing that noise.

When a source radiates noise outdoors, the
sound levels naturally decrease with distance.
At distances greater than four times its
average linear dimension (the 'far field") sound
energy radiates according to the inverse-square
law and decreases by 6 dB for each doubling of
the distance from the noise source.  The
deviation from this law grows greater with
higher frequencies and is very dependent
on humidity and temperature, as shown.

Table 1:  Decrease of sound-pressure levels due
to energy absorption in air by molecular
processes, stated in dB per mile.

Relative  Temperature  1000 Hz  2000  4000  6300
humidity              and below  Hz    Hz    Hz
   %          oF
30



50


70


59
68
77
86
50
68
77
86
50
68
77
86
2
2
2
2
2
2
2
2
2
2
2
2
25
21
20
19
17
17
17
16
15
15
15
14
85
66
54
49
50
42
41
41
39
37
37
36
185
147
120
99
110
88
77
75
79
70
68
67
                                                            Sound  propagation  through  extensive  forests  has
                                                            a  reasonable  attenuation of  2  dB  per 100  feet.
                                                            The  thickness of the  forest  affects  sound
                                                            propagation,  but reaches a plateau,  regardless
                                                            of density, at  about  10 dB -for all  frequencies.
                                                            This value  fluctuates  due  to wind and  other
                                                            factors,  so it  is  not  constantly  accurate.
                                                    51

-------
01-016
                                        EMISSION & SUPPRESSION
    Wind primarily  redistributes the sound energy
     in different directions.  When the gradient of
    the wind velocity  is positive (downwind from
    the source), sound energy is refracted downwards.
    Likewise, as temperature increases with
    increasing height  (positive gradient), it
    refracts sound energy downwards in all directions
    increasing the sound level pressure.  Wind also
    causes  leaf rustling on trees.  There are two
    species of poplar  and birch which generate
    noise at levels as high as 40 dB at wind speeds
    of 5 mph.

    The measurements discussed here apply to the
     intrusion of noise from woodland operations
    upon those using the woods for recreational
    purposes.  Most criteria for intrusiveness
    are based on typical urban environments, and
    very little has been done on forest noise.  In
    places  such as concert halls, however, criteria
    for noise are set, and at very low  levels.  It
     is assumed that these criteria will be the
    same for forest noise.

    Such criteria are  expressed in terms of Noise
    Criteria (NO curves, which specify noise  levels
    allowed at each octave band.  The annoyance of
    a measured noise is found by plotting levels
    superimposed on the NC curves.  In these terms,
    the background noise in concert halls should
    not exceed NC 15 to NC 20.  However, this
    applies to continuous noise, and time-varying
    noise such as those produced by a chainsaw
    would  lower the criteria to NC 10-15.

    The threshold of hearing (12 dB lower than 10)
    could also be used as a criterion for forest
    noise,  although this assumes that there are no
    masking noises  in  the vicinity of the listener.
    01-016

    POLYURETHANE  FOAM CONTROLS MACHINE NOISE

    Sound and  Vibration

    Vol  5 No 7:12, JUL,  1971
     The  noise  from  high-speed computer printers
     has  been  lowered  from 80 to 55 dB using a
     sound  absorption  material made of compressed
     polyurethance foam.  The major source of noise
     printers  is  a  large  number of rapid-fire
     hammers—132 or more—that print out up to
     1250 I ines per  minutp.

     The  cornp.,.	^  t-jjm  is made by applying heat
     and  pressure to the  original material until
     its  dimensions  are reduced Dy the desired
     ratio.  This process changes the internal
     structure  of the  foam,  improving its sound
     absorbing  properties.   In the computer printer
     application, the  brand used was Scottfelt
     and  the printer was  the RCA 70/242-30.  The
original thickness of the foam layers was
attached to interior metal  surfaces of the
printers using adhesive, as well  as installed
on a sound baffle near a point where cooling
air entered the printer.  Other materials
considered, but not used included glass fiber
and closed eel I  foam.

Other applications of the material have
included tractor engine compartments and gas
turbine power plants, both stationary and
ai rcraft types.
01-017

Jackson, C. E.
Grimster, W. F.

West I and Helicopters, Ltd.,
Yeovi I  /England/

HUMAN ASPECTS OF VIBRATION AND NOISE IN
HELICOPTERS

Journal of Sound and Vibration

Vol 20 No 4:343-351, 1972
Types and sources of helicopter vibration,
methods of vibration testing and monitoring,
methods of vibration reduction, and internal
and external noise are discussed and information
is given on results of internal cabin noise
reduction.

The fundamental mechanics of the helicopter,
involving a number of rotating components, make
the machine subject to vibration and noise.  The
prime sources of excitation are the main rotor,
the transmission system, the tail rotor and the
engine.  This frequency range of 20 to 15,000
Hz encompasses main and tail rotor harmonics,
gearbox noise, noise generated by engine
components and aerodynamical Iy-produced broad-
band noise.

Externally, the predominant noise is generated
aerodynamically by the main and tail rotors.

Harmonics of the main rotor blade passing
frequency occur at the  low frequency end of
the audio range.  Tail rotor rotational
harmonics, broad-band noise from the main
rotor and gear meshing noise dominate the
mid-frequency  region and engine compressor
orders exist  above about 10 kHz.

The subjectively dominant  internal  noise sources
are transmission (gear meshing) orders.
                                                         52

-------
                                                                                                          01-018
                                     EMISSION &  SUPPRESSION
If the helicopter is to fulfill future civil
requirements  it will be necessary to  reduce
cabin noise further.  Although the  internal
noise in military helicopters  is considerable
the crew wear helmets which attenuate the  level
at the ear.

Noise can be  transmitted to the cockpit  and
cabin as airborne noise and/or as structure
borne vibration.  Present soundproofing  schemes
consist of  lining the cabin with an absorbent
material such as fiberglass.  The whole  surface
area of the cabin is treated.

Considerable  reductions in cabin noise  levels
have been obtained.  The mid and upper audio
frequency region of the noise  is subjectively
most important and  in this area the greatest
reductions are apparent.

Future investigations are planned to  optimize
soundproofing, in an attempt to reduce the noise
levels even further.

It appears that the subjective effects of noise
and vibration are additive, and thus  the
helicopter is a vehicle on which combined field
and laboratory environmental  studies  should  be
d i rected.
                    FriqueneylHi)

               Figure 1 Helicopter noise sources.
          HUMAN AS?EC15 OF HELICOPTER VIBRATION
                                : 80OO 6000
                  Oetov* centre frequency (Hi)

        Figure 2. Effect of cabin soundproofing
 01-018

 Gregoire,  M.  C.
 Streckenbach, J. M.

 Boeing Co.,  Seattle, WA

 Commercial  Airplane Group
 P.  0.  Box  3707,  Zip 98124

 EFFECTS OF  AIRCRAFT OPERATION ON COMMUNITY NOISE

 Seattle, Boeing, JUN, 1971, 10 p.
 Industry  and  government studies in
 response  to airlines,  airframe and engine
 manufacturers,  and  local  airport authorities
 to  reduce aircraft  generated noise in airport
 communities are reported.

 Three  general  areas of community noise
 improvement are summarized as:
 1)   Reduction  of the noise at its source by
 quieting  the  engine installations on the
 aircraft
 2)   Changes in  land utilization in airport
 communities
 3)   Changes in  regulatory  and operational
 procedures  in  the vicinity of airports.

 Considerable work now  being done in industry and
 government  programs is related to examining
 means  of  retrofitting  the  existing fleet of
 commercial  fanjet transport aircraft to
 significantly  reduce their community noise
 levels.   The magnitude of  noise reduction
 attained  is closely related to technical
 feasibility and to  the economics of airplane
 modification and  operation.

 Both Federal and  local  agencies are continuing
 to study  the possibilities  of community  noise
 relief through  better  land  utilization.   Such
 studies encompass the  subjects of  improved
 planning  for new  airports,  tightened building
 codes  and zoning  restrictions,  and revised land
 utilization around  existing  airports.  Economics
 is an  important and  unavoidable consideration in
 land utilization  studies.

 Noise  reduction  through operational  procedures
 offers much relief  to  the  community at
 relatively  little cost, without affecting  safety.
 These  procedures  include Federal  and  local
 regulations and operating  procedures  available
 to the ai  rli nes.

 Holding and maneuver attitudes  can  be  raised
 by Federal  and  local regulation.   Traffic
 patterns and routes can be optimized  over  less
 populated  areas.  If glide  slopes  are  steepened
 by i degree, significant noise  reduction will
occur.   Finally,  the glide  slope intercept
altitude can be raised.  If  all  of  these points
were accomplished.  Federal and  local  regulation
would be responsible for a good  deal  of noise
 reduction.
                                                    53

-------
01-019
                                         EMISSIONS SUPPRESSION
     Operational  procedures available  to the  airlines
     themselves  could  also effect changes  in  aircraft
     noise  levels.  Noise can  be reduced considerably
     by  delaying landing gear  and flap extension.
     Two-segment approaches, or  intercepting  the
     final  glide slope from a  steep  descent,  will
     keep aircraft  at  a high  level over the community,
     and the  noise  level will  remain  low.  Flap
     position  during approach  and landing  could be
     set at a  lesser angle, producing  less noise.
     This would  require additional runway  yardage.
     Take-off  procedures could be modified by
     implementing a power cutback at an acceptable
     aItitude.
                    2345
                   DIStANCE FROM THRESHOLD (NMD
       FIGURE 1.   Noise Footprint Comparisons of
                  Two-Segment Approaches
    01-019

    Kugler, B. A.
    Anderson, 6. S.

    Bolt, Beranek, and Newman,  Inc.,
    Canoga Park, CA

    Zip 91303

    AUTOMOTIVE NOISE ENVIRONMENTAL  IMPACT
    AND CONTROL

    At:  Highway Research Board Annual Meeting,
    Ingenjoersvetenskapsakademien,  Sweden,  1972

    Canoga Park, CA, Bolt, Beranek, and Newman,
    1972, 30p.
    The  units  used to describe automotive noise,
    which  is the most widespread and  important
    contributor of urban  noise, the current criteria
    used  in assessing the  impact-of traffic noise on
    people, various  automotive sources that combine
    to create  traffic noise, and control of motor
    vehicle noise are discussed.
The effects of automotive noise on people can
be divided into the subjective effects of
annoyance, nuisance, and dissatisfaction and
interference with tasks such as sleep, speech
and learning.  Interference with speech and T.V.
listening is the predominant complaint against
automotive noise and interference with sleep  is
also often cited.   In describing subjective
response, measurements of time average noise
levels and the magnitude and frequency of the
occurrence of peak noise levels are  important.
In conjunction with these points, criteria
specifying maximum noise levels to which
people will  agree have been derived.  One
method, known as the statistical time
distribution, identifies each noise  level with
the percentage of time which that level  is
exceeded.  For example, L10 is that  level which
is exceeded  \0% of the time.

Automobiles, by sheer number alone,  produce the
largest source of motor vehicle noise.  Tire/
roadway noise is the main contributor from autos
at high speeds.  Diesel trucks are the noisiest
vehicles on the road.  Figure 1 shows the
spectra of typical noise sources from trucks:
                                                                     31.5   43    125   250    503    1000   2000   4000   3COO
                                                                                 Octave Bond Center Frequency In Hz
       FIGURE 1.  TYPICAL BREAKDOWN OF TRUCK NOISE
Motorcycles produce most noise from their
exhaust systems.

Predictions of traffic noise under different
roadway conditions can be made by statistical
time distribution, given vehicle volume and
average speed.

Noise can be controlled at three points: the
source, the receiver, and along the transmission
path.  Limiting noise at the source can be
achieved by legislation on noise levels of
motor vehicles.  Control  at the receiver can be
obtained by zoning and planning of land use, and
by acoustic insulation of buildings.  Reducing
noise along the transmission path can be
achieved by design of roadway configurations and
alignments.  Increased distance, relocation,
and depression/elevation of the roadway will
reduce noise levels.  Construction of earth
berms will also control noise considerably.
Depression of the roadway, on one case, resulted
in a 13.5 dBA noise reduction.
                                                         54

-------
                                                                                                         01-020
                                     EMISSIONS SUPPRESSION
Proper planning seems to be the best and most
effective criterion for control of automotive
01-020

Erskine, J. B.
Brunt, J.

Imperial Chemical Industries Ltd.,
Billingham /England/

Agricultural  Division, Teeside

NOISE FROM CHEMICAL PLANT EQUIPMENT

Annals of Occupational Hygiene

Vol 14 No 2:91-99, 1971
The large scale industrial noise problem
resulting from increases  in chemical plant
and equipment size together with the use of
higher fluid velocities is discussed.

One problem is compressor noise, due to blade
passage, turbulence in rotating elements of
centrifigual compressors, turbulance in by-pass
systems and normal turbulent flow in pipes.
Noise reduction has been accomplished by
removing diffuser vanes, reducing the surface
area, fitting silencers, and cladding pipes.

A second problem, fan noise, comes mostly from
air coolers, and has caused complaints from the
community.  A reduction of 6 dBA was achieved at
one plant by using both inertia and absorption
silencers.

Efforts to silence the third problem, flarestacks
have been disappointing so far.  Noise is a
function of the steam rate per nozzle, not the
overall steam rate.  Evenness of combustion is
a negligible factor in noisiness.  Use of
peripheral steam jets of different orientation
resulted  in a 7-9 dBA improvement; however,
this is inadequate.  New methods of flaring gas
need to be developed.

Two components of noise from vents are noise
from pressure let down and atmosphere mixing.
The sizing of pipes and vent silencers must be
applied according to location, and hence there
are no simple design rules.

For the most effective noise control, it is
suggested that possible noise sources be treated
at the design stage.
01-021

GREAT POSSIBILITIES IN NOISE ABATEMENT

Nagy  lehetosegek a zaj csokkentesere

Ujitok Lapja (Budapest)

Vol  23 No 20:13-14, 1971
The SILKA sound damper, based on a patent
granted to physicist Domokos Horvath and
mechanical engineer Gyorgy Sardi, went
into series production at the Somogy County
Enterprise in Kaposvar, Hungary.  The
patent, granted in 1970 and entitled
"Sound damping enclosure for damping noise
caused by flowing gases, for example,
motor exhaust gases," is an enclosure
bounded by walls consisting of multilayered
film with dead space between the layers
which are filled with loose granular,
porous or other vibration damping media.
The invention has been in use in the
Ganz-MAVAG Engine Testing Station since
1966.  Noise has been abated in the plant
environment, and an attenuation of low
frequency noise of 30 dB at 12 Hz has
been attained.  Previously, the noise
level in the plant environment had reached
NC 105, extending into distant communities.
The level is presently below NC 70 (about
75 dBA).

Prototypes of the noise damper will be tested
in apartment house ventilation systems in
Obuda and Zuglo.  Tests on prototypes of the
MONO apartment house ventilation systems
produced by the Ventilator Plant and equipped
with the noise attenuation device show
attenuation of 15 dB.  A 30-40 dB attenuation
from 110 dB to approximately NC 65 was also
achieved  in exhaust noise from the compressor
room of the Pecs Leather Plant.

The noise damping device is to be applied to
damping noise from diesel and Otto engines in
engine testing stations, ventilator noise
from exhaust and air conditioning systems
in apartment houses, air filtering systems,
and noise from gas turbine exhaust systems.
                                                     55

-------
01-022
                                           EMISSIONS SUPPRESSION
    01-022

    Myakshin,  V.  N.

    Scientific Research  Institute of Building
    Construction,  Kiev /USSR/

    REDUCTION  OF  NOISE FROM COMPRESSOR  INSTALLATIONS

    Snizheniye Shuma  Kompressornykh Stantsiy

    Tekhnologiya  i Organizatsiya Proizvodstva (Kiev)

    No 1:87-88,  1971
Further reduction in noise emissions to nearby
housing can be achieved  by locating  the
compressor installation  away  from housing
areas, by orienting  the  intake and exhaust
pipes away from these areas,  and  by  using
factory buildings for screening.
    Effective  noise  reduction by means of a simple
    pipe muffler  was  achieved for a piston-type
    air compressor installation  located  in a
    separate shed on  factory property, enabling
    the compressor installation  to meet  the Soviet
    norms for  noise  emitted to adjacent
    residential areas.   Piston compressor noise
    is composed of airborne noise from the air
    intake and exhaust,  and noise radiated from
    the body of the  compressor  itself.   The noise
    spectra of four  Soviet compressor  installations
    would not  meet the  legal  limits within certain
    di stances.

    Since noise radiated from the compressor body
    is mostly  contained  inside the shed,  it is the
    intake and exhaust noise of  the engine that
    accounts for  most of the noise heard a1 a
    distance from the installation.  Measured at
    the pipes, it reached 102-104 dBA.

    A simple cylindrical  muffler attached to the
    air intake pipe  proved effective for reducing
    noise for compressors of capacity  of up to
    50 cubic meters  per  minute  (Figure  1).
    This muffler  is  simple to make, durable, and
    is effective  over a  wide  range of  frequencies.
    By using this muffler, a Soviet  IVV-10/8
    compressor (capacity 10 cubic meters per
    minute at eight  atmospheres) was quieted by
    13-15 dB over a  wide frequency range.
                  ///r
    Figure 1.  Cylindrical  muffler for  exhaust pipe.
    1.  Outside surface of muffler.
    2.  Sound  absorbing material  (density  15 kG/m3,
    layer thickness 100mm).
    3.  Layer  of fiberglass  0.1mm thick.
    4.  Perforations 5mm in  diameter in  inner wall
    of muffler, spaced 10mm  apart.   Length of
    muffler: 1  meter.
    5.  Air intake pipe with flange.
01-023

Hi rabayash i, T.

H. L. Blachford, Inc., Troy, Ml

NOISE AND THE SNOWMOBILE

In: Crocker, M., Proceedings of the Purdue
Noise Control Conference, JUL 14-16, 1971

Lafayette, Purdue Univ., 1972, 594 p.
(p. 77-79)
The noise problem of the snowmobile is
discussed with special  emphasis on methods
of measurement and control.  Snowmobiles
have found wide use both for recreation and
utility.  Conservationists are concerned about
th i s no i se impact on wildlife.  In response
legislatures are acting on noise limits.
Snowmobile noise can cause permanent hearing
loss and has been responsible for many accidents
because of its masking effect, making warning
signaIs i naud ible.

To measure the sound pressure levels, the
snowmobile was tested in a large semi-anechoic
room with the machine blocked up so as to
allow the drive track to run free.   Recordings
were taken at five positions around the machine.
The levels of a new machine were 98-101 dBA.

The following modifications were most effective:

1.  All unnecessary openings in the body were
    sealed.  Openings which were required for
    engine cooling were retained.

2.  One inch of polyurethane acoustical foam
    was stuck to the interior surface of the
    engi ne cow Ii ng.

3.  Three-quarter inch embossed polyurethane
    acoustical  foam was stuck to the interior
    surface of the instrument console.

4.  A silencer was attached to the carburetor
    intake.
5.
    The foot-well  openings in the engine cowling
    were reduced to a minimum practical  size.
                                                        56

-------
                                                                                                         01-024
                                       EMISSIONS  SUPPRESSION
These modifications did not lower the noise
level around the machine, but the value at the
operator's ear was lowered by 5 dBA.   In
order to lower sound pressure levels  around
the machine an effective engine exhaust muffler
must be added.
 01-024

 Faulkner,  L.  L.

 Ohio  State Univ., Columbus, OH

 Dept. of Mechanical  Engineering

 NOISE CHARACTER OF A RIDING LAWN MOWER

 Columbus, OH, Ohio State Univ.,  12p,  1971
 Minor modifications to an 8 HP riding  lawn
 mower enabled  it to meet the ANSI  Standard
 B71.1 recommendations for maximum  noise  levels
 at  the operator's ear; the  limit  in this
 standard, which became effective JUN  1,  1971,
 was 95 dBA.  Various noise  levels  measured
 at  the ear  level microphone position were as
 follows:

 Configuration  of Mower   Sound Level  (dBA)
 No Muffler
 Stock muffler
 Stock muffler with
   engine cover
 Experimental muffler
   with engi ne cover
98
93

87

85
Another  useful method was reduction of maximum
engine speed.  However, meeting community noise
ordinance  limits such as those  in the Chicago
Code will  become quite difficult as the  limits
become more  stringent with time.  Engine noise
may be reduced, revealing an even tougher
problem—blade noise.  The Chicago Code gives
a maximum  limit of 74 dBA at 50 ft effective
JAN 1, 1972, and this limit drops to 65 dBA by
JAN, 1978.

The two  riding mowers tested had 4 cycle,
aircooled, non-dynamicaIly balanced engines
producing  3600 maximum RPM.  Vibrating loose
parts such as the seat and fenders were
significant  noise sources.  A 3 dBA reduction
was obtained merely by placing a hand on a
vibrating  fender.  It'is recommended fenders
be removed during these tests, and that
manufacturers eliminate them.  A dynamically
balanced 8 HP engine was 4 dB quieter at
ear level than the standard mower engine.
This engine  would cost $12, or $3/dB more
than the standard one.

Replacement  of the stock "tin can" muffler
with an experimental  muItichambered muffler
                            reduced  noise only 2 dBA, but perceived
                            reduction of  loudness was greater because the
                            new muffler eliminated harsh-sounding components
                            at the firing frequency.   Improved mufflers
                            alone are not the answer because direct
                            radiation from the engine casting was the
                            controlling source, not the exhaust noise.
                            Tests with a  long tailpipe completely
                            eliminating exhaust noise confirmed this.
                            Likewise, vibration isolation of the engine
                            from the frame had no effect because the engine
                            casing itself was the controlling source.  A
                            partial  sheet metal cover with absorption
                            material on the engine side gave a 6 dBA
                            reduction, however.  The absorption material
                            was glassfiber blanket approximately 2  in
                            thick.

                            The combined  reductions achieved by the above
                            means are enough to meet the limit of 74 dBA
                            at 50 ft, but meeting the future limits of
                            70 dBA (1975) and 65 dBA (1978) will be a
                            reaI challenge.

                            The only other possible means of reduction,
                            other than drastic engine and blade redesign,
                            is reduction of engine speed.  For these two
                            mowers,  with  stock equipment, a relationship
                            of about 1 dBA/200 RPM was observed:
                            Engine  speed
                            3380 RPM
                            3175
                            2875
                            2550
                            2400
                    Sound level  at ear
                    of operator (dBA)

                           92
                           91 .5
                           89.5
                           88
                           87
Reducing engine speed will  perhaps be the most
common way to meet legal  limits,  since it
requires only the change  of the governor
setti ng.
                           01-025

                           Caccavari, C.

                           Chicago  Department of Environmental Control,  IL

                           Engineering Div., Dept. of Environmental
                           Control,  320 N. Clark St., Chicago, Zip 60610

                           NOISE STUDY OF AN AIR PILE DRIVER

                           Chicago,  Dept. of Environmental Control,  1971,
                           9p.
                           The problem of noise from the use of pile
                           drivers on steel sheet piles at a downtown
                           construction site was studied and a three-sided
                           enclosure developed that produced some quieting.
                                                    57

-------
01-026
                                           EMISSIONS SUPPRESSION
    The study, performed by the City of Chicago's
    Department of Environmental Control, was done
    on pile driving operations at the First National
    Bank construction site.  The equipment was a
    double action air pile driver.  Preliminary
    measurements established the duration of the
    peak noise, the frequency characteristics of
    the noise, the repetition rate, and the true
    peak level (about 122 dB at 25 feet, equivalent
    to 102 RMS dBA and  106 RMS dBC).

    The City  recommended that a three-sided
    enclosure be installed on the existing support
    frames of the pile  driver.  The enclosure was
    left open in the front to provide visual freedon
    for the crane operator, but it still partially
    shielded observers  to the rear of the pile
    driving operation.  The enclosure was
    constructed of an outer steel shell (i inch
    sheet steel), coated with a damping compound
    to minimize the vibration of the shell (i inch
    "Vibradamp") and lined with U inches of open
    celled polyurethane, an acoustical absorption
    material.

    A test was made where measurements were taken
    as the enclosure was elevated above the pile
    driver and gradually  lowered over it.  The
    results showed a 15 dB reduction of the peak
    level (and a reduction of 7 dBA in the "A-
    weighted"  level) to the rear of the pile
    driver, and a slight reduction to the side of
    the pile  driver.  (See Table.)
     Sound  level
                      Without
                      enclosure
With
enclosure
     At  rear  of  enclosure  (about 25  ft.):
     Peak  levels (dB)      123              108
     RMS Peak (dBA)        106              99
     RMS Peak (dBC)        108              104

     At  site  of  enclosure  (about 25  ft.):
     Peak  level  (dB)       113              110
     RMS Peak (dBA)        107              103
     RMS Peak (dBC)        108              105

     Noise  levels  at the First National
     Bank site.
    Further reductions could be achieved by
    improving the design of the enclosure, which
    in this case did not extend far enough down
    and forward because of the presence of an
    angle  iron support frame.  The enclosure
    could  be slotted to allow it to descend upon
    the sheet pilings, thus better cutting off
    noise  emissions.  By making the enclosure
    more triangular  in shape and eliminating the
    opening on the fourth or open side through
    the use of a plexiglass or glass shield, the
    size of openings  in the enclosure could be
    further reduced.  Finally, thicker acoustical
    treatment would  provide  increased attenuation
    at the lower frequencies.

     In this case, the study was initiated from a
    series of complaints received by the Department
    of Environmental Control.  A series of meetings
                          with  representatives  of  the  bank  and  the
                          construction  company  led to  the decision to try
                          the enclosure.   Additional actions  agreed upon
                          were  that air mufflers or baffles were  to be
                          installed on  all  pile driver units, and a
                          vibro driver  was  to be used  for extracting the
                          sheet metal piles after  the  completion  of the
                          project.

                          The vibro driver  is a different type  of pile
                          driver that operates  at  speeds of 18  to 30
                          cycles per second.  The  vibro driver's  noise
                          level, as measured  at a  second construction
                          site, was between 82  and 84  dBA at  20 feet,
                          markedly  quieter  than the air pile  driver.  This
                          device functions  well  as a driver only  in
                          certain types of  soils.   However, it  is
                          effective for the extraction of sheet metal
                          piling in all  types of soils.
01-026

Weber, 6.

Technische Universitaet, Hannover
/West Germany/

SONIC BOOM EFFECTS 11.1: STRUCTURES AND TERRAIN

Journal of Sound and Vibration

Vol  20 No 4:505-509, 1972
                          Effects on structures due to pressure waves
                          from explosions  and  guns  have been known and
                          studied for a long time.   Three general  sets
                          of  parameters determine the  effect of sonic
                          booms on the structures and  terrain;  (i) the
                          generation; (ii) the propagation of shock
                          waves;  (iii) the characteristics of the
                          structures.

                          When an acoustic shock wave  strikes the  ground,
                          a ground wave is set in motion and travels  at
                          a speed which is a function  of the terrain
                          and its composition.  A component of  this
                          ground  motion travels along  the surface
                          (Rayleigh wave), exposing buildings and  other
                          structures on the ground.  Its effect on
                          structures would no  be sufficient to  cause
                          damage.  It has  been shown that ground motions
                          associated with  sonic booms  are usually  of
                          the same order as those associated with  the
                          passage of vehicles.  The structural  vibration
                          induced by ground motion  is  far less  than
                          excitation by the acoustic shock wave.

                          The effect of the ground  motion on surface
                          topographical features is the same as that
                          already discussed for structures.  The effect
                          on  underground features such as mines has not
                          been studied, but should  be  noted that the
                          amplitude of the ground motion caused by the
                          sonic boom usually diminishes with depth.
                                                         58

-------
                                                                                                          01-027
                                        EMISSIONS SUPPRESSION
The main effect of the boom on topographical
features, or on structures, will come from
the direct excitation by the acoustic shock
wave.  On many features, for example cliffs,
existing natural disturbances such as wind
have been found to be compatible with or
greater than sonic boom disturbance.  A
sonic  boom could trigger a fall, but this
would  only be slightly premature to the
naturally occurring event.  Damage to primary
structure of dwellings even under extreme
assumptions  is not be expected.  Structural
elements with  large surfaces and small masses
and not preloaded by other structural elements,
are more susceptible to booms than any other
structural part.  Therefore damage to plaster,
panes, suspended ceilings and roofs can be
expected to  be more numerous than other
structural damages.  Damage expectancy will
decrease with overpressure, but theoretically
there  is no  overpressure  level at which damage
 is  impossible.  Relevant boom characteristics
on a certain structural part are normally not
known  mainly because the free field waveform
 is altered by the structure itself and by
reflections  from neighboring buildings.
 been  successful.   The  best way  to  prevent
 damage  from  sonic  booms  is to keep buildings
 in  a  good  state of preservation.

 Suitable sonic boom generators  can be  used to
 obtain  fatigue data on building elements or
 sections.  Since there is some  evidence that
 higher  order modes can play an  important part
 in  the  damage mechanism,  it seem prudent
 that  experimental  generators produce N-waves
 that  contain all frequencies found in  a real
 sonic boom.  Three items appear pertinent for
 general research.   The first is glass, which
 features extensively in sonic boom claims
 in  walls where the point of interest is fatigue
 work.   Third, crack propagation in plaster and
 other structural elements is important.

 Data  on structures should be standardized to
 facilitate comparison  among different
 experiments.
 In an Oklahoma City study with 1235 sonic booms
 having an average maximum intensity of about
 70 N/sq.m. there was no evidence of cumulative
 damage in the four test structures intensively
 studies throughout the program.  By a suitable
 choice of buildings and by an examination of
 their maintenance histories, it is feasible
 that appropriate fatigue data could be
 accumulated on the problem of repeated sonic
 booms.

 Effects of booms on structures vary from
 slight vibrations, detectable only by
 special equipment, to severe vibrations which
 might cause damage.  Type and number of
 damages in structures follow a certain order.
 This is determined by the peak overpressure,
 the time history of the boom shock waves
 and the susceptibility of the structural
 element.  Glass panes and plaster are more
 susceptible than roofs which in turn are
 more susceptible than walls.  In connection
 with an exposure to a sonic boom of very high
 intensity in MAY 1970 over the German town of
 Westerburg and some villages situated 1 km to
 the south, 378 damage claims were filed.  Most
 involved damage to glass panes and slated
 roofs where slates were shaken up.  Some
 chimneys were damaged, some closed doors went
 off the hinges and door panels were broken.
 No serious damage on the main house structures
 was recorded.  Extended criteria for statistical
 assessment need to be developed.  These can
 be based on both figures of damage claims and
 results from experimental  investigations.  In
 the case of one single boom with the intensity
 of 125 N/sq.m. which exposes an urban community
with a population of 500,000 people and 20
window panes/person, one window (out of ten
million)  can be expected to be broken.

 In several  cases, preventive measures chiefly
performed  to protect plaster and glass  have
01-027

Wi1 Iiams, T. E.

Southampton Univ. /England/

Dept, of Civil Engineering, University of
Southampton, Highfield, Southampton S09 5NH

HIGHWAY ENGINEERING AND THE INFLUENCE OF
GEOMETRIC DESIGN CHARACTERISTICS ON NOISE

Journal of Sound & Vibration

Vol  15 No 1:17-22, 1971
 In contrast to the quantitative approaches to
traffic and design problems which are available,
 in highway engineering, noise is an area in
which the boundaries between quantitative and
qualitative assessments are frequently diffuse.

The motorway requires the segregation of
vehicles from pedestrians; this allows its
design as a ground level facility, an elevated
structure, depressed in a cutting or in a
tunnel.  It is feasible to submerge most urban
motorways in tunnels, but the cost is so much
greater than elevated or ground level
construction that tunnels are kept to a minimum.
Thus, what would be desirable in terms of
reduction of noise is usually unacceptable on
grounds of cost, and disruption of services.
The general  effect of an elevated motorway
or one which is in a cutting is a reduced level
of noise in  its vicinity, although the
introduction of ramps and slip roads on
gradients result in concentrations of
relatively higher levels of noise in their
particular localities.
                                                    59

-------
02-001
                                                PHYSIOLOGICAL
    The results of a comprehensive  factual  survey
    of 600 properties and 200 sites in  various
    parts of the United States on the effects of
    landscape treatment, highway  alignment  and
    traffic noise on property indicated the
    following: (1) The depressed  or subsurface
    highway is potentially the greatest single
    reducer of noise level.  (2) Tree plantings
    affect noise levels only slightly.  (3)  In
    tall  apartment buildings which  are  adjacent
    to roads of the motorway type,  the  occupants
    found the disturbance from traffic  noise
    highly objectionable. (4) Trucks were
    considered the most objectionable source of
    noise, insofar as it disturbed  normal  domestic
    activities. (5) The presence  of limited-access
    highways of the motorway type did not result
    in the general  devaluation of houses and
    properties which were adjacent  to them. (6)
    A general equation was computed by  multiple
    regression in indicate the probable combined
    effects of distance, alignment  and  vegetation
    of the level  of noise from road traffic.
    For different types  of  road  surfaces,  the
    following equations  were established  for
    passenger cars:
    Open textured asphalt:

    Motorway concrete:

    New asphalt:
noise level  (dBA)=
28+30 log (speed).
noise level  (dBA)=
23+30 log (speed).
noise level  (dBA)=
18+30 log (speed).
    It is noted that the most effective resistance
    to skidding is generally obtained from new
    concrete and new asphalt.  A high quality
    surface is therefore beneficial  both in terms
    of safety and noise.  The methods of shielding
    from traffic noise the occupants of properties
    adjacent to major highways require attention
    to landscape treatment and the insulation  of
    buiIdings.

    The importance of research in the field of
    barrier design has increased because of the
    problems which arise in regard to the planning
    and implementation of urban projects.
                                   02-001

                                   Karlsson, C. G.

                                   Royal  Caroline Inst., Stockholm /Sweden/

                                   MAN AND NOISE STRESS AND RISK OF INJURY

                                   In: Jansson, P. G. , Conferences in Connection
                                   with the International Air Pollution Control
                                   and Noise Abatement Exhibition, SEPT 1-6, 1971

                                   Joenkoeping, Sweden,  1971, 525 p. (p. 4:1-4:6)
An estimate shows that more than half the
machines in heavy industry can cause noise with
levels above 90 dBA, and that roughly 50$ of
industrial  workplaces have noise levels of over
85 dBA.  Since noise is known to produce
harmful effects in man, a study was made on
the physiological  and psychological effects
of noise on 20 female card punch operators.

Group 1 was exposed to sound levels of 76, 82,
88, & 94 dBC on 4 consecutive working days
respectively while engaged in their normal work.
The other group was exposed to the same sound
levels in reverse sequence whi le working.
The normal  sound level  of the card puching
machines was 76 dBC.  The other levels were
produced by playing tape recordings of punching
noise and superimposing this on the 76 dBC
level.  Preliminary findings show that only
slight increases in physiological  and mental
stress were observed.  No proportionality was
established between the sound level in dBC and
the mental  and physical reactions recorded.
These sound levels, physically speaking quite
high, produced only mild stress reactions.  The
reason for this is believed to be a favorable
attitude toward the test and hence toward the
noise.  However, a positive relation was
confined between subjective disturbance, and
secretion of adrenalin and noradrenaI in.
Considerable individual differences were
exhibited in reactions to the same noise
stimuI us.
                                                                02-002

                                                                Abrol ,  B.  M.
                                                                Nath,  L.  M.
                                                                Sahai,  A.  N.

                                                                All-India  Institute  of  Medical  Sciences
                                                                New  Dehli  /India/

                                                                NOISE  AND  ACOUSTIC TRAUMA
                                                                NOISE  LEVELS  IN  DISCOTHEQUES IN NEW DELHI

                                                                Indian  Journal  of  Medical Research

                                                                Vol  58  No 12:1758-1763, 1970
                                                        60

-------
                                                                                                         02-003
                                             PHYSIOLOGICAL
Live music  in discotheques may be more
dangerous to hearing than recorded music of
seemingly equal  loudness. Discotheques  in
New Delhi,  India, were surveyed for potentially
dangerous noise  levels, both when recorded
music  (8 discotheques) and when live music
interspersed with recorded music (2
discotheques) was being played.  Bruel and
Kjaer  equipment was used.

In a typical discotheque the general noise
level  (GNL), based on an average of 10 trials,
was 90 dB for  recorded music and 109 dB for
live music  from a "rock'1 band.

Frequency analysis showed that highest sound
pressure levels were found in the lower octave
bands  (125, 250, and 500 Hz) for both recorded
and  live music, but that  levels in the higher
bands  were  also considerable.  Sound pressure
levels in the 4000 Hz band ranged from 61-81
dB for recorded music  in the various
discotheques.  Levels for live music  in the
same octave band were 84 and 86 dB.  Background
noise  was typically 20-30 dB down from recorded
music  levels at all frequencies.

The authors account for the significantly
higher sound levels for live music,  as opposed
to recorded music, by assuming that volume of
the recorded music was set to seem as loud as
the live music for which it was substituting.
One of the factors which contributes to the
sensation of loudness is the distortion content
of the signal, and it is likely that distortion
levels were markedly higher with recorded
music.  They conclude that the levels measured
for live music definitely exceeded levels
usually accepted as ear damage risk criteria
(Lebo  and Oliphant, California Medicine,Vol
107 (1967), p. 378), and that risk of acoustic
trauma existed not only for the musicians, but
also to habituees if they were particularly
susceptible to such a noise trauma.
Measurements were conducted in a weaving
plant to determine the affects of noise
on workers.  Two groups were investigated:
Group I  worked on a shuttle looms type
TSFS, reaching noise  levels from 108 to 113 dB,
and group  II operated microshuttle  looms type
STB, reaching noise levels from 100 to 102 dB.
Measurements on the workers were taken 4 times
per day: before work,  before and after lunch,
and at the end of the work shift.

The weavers in Group  I showed more pronounced
changes in the nervous system and the systolic
arterial pressure.  These changes result in
fatigue, headaches and ringing in the ears.
All of these symptoms cannot be relieved
by a noise free period during lunch or
during time away from work.  Definite
measures should be taken to relieve the nervous
tension caused by noise exposure, which
can easily turn into trauma.
02-004

Becker, R.
Bonk, U.
KiessIi ng, P.

East Germany

NOISE LEVEL MEASUREMENTS DURING A FISHING
EXPEDITION

SchalIpegeImessungen Waehrend einer Fangreise

Seewi rtschaft

Vol 3 No 12:926-928, 1971
02-003

Gorshkov, S.  I .
Kohan, N. A.
Kolesnikova,  A.  V.

PHYSIOLOGICAL CHANGES IN WEAVERS OPERATING
LOOMS WITH DIFFERENT NOISE INTENSITY

Fiziologicheskiye Sdvigi u Tkachey Obsluzhi-
vayushchikh Tkatskiye Stanki  s Raznymi
Urovnyami Shuma

Gigiyena i  Sanitariya

Vol  37 No 1:29-32,  1972
Noise measurements were conducted in East
Germany on the fishing vessel  "WiI I i  Bredel"
during its 100 day expedition.  Noise meter
101 of the Technical  Vibration and Acoustics
Plant in Dresden was employed and the noise
levels were measured on the A, B, C
weighting scale.

All possible noise sources were taken into
account and measured .  The noise levels
ranged from 62 dBA in rooms located on the
first deck to 104 dBA at the main oil-diesel
machine.

Recommended norms for work places were
considerably exceeded on "WiI Ii  Bredel".
Most complaints came from patients of the
hospital, which is located on the deck where
3 elevators for fish supplies are situated.
The highest noise levels come from the
conveyor-refrigeration unit and "fish flour
mi I I".
                                                    61

-------
02-005
                                                 PHYSIOLOGICAL
    The guards at the main-machine use  individual
    Hermetos ear plugs produced by Prothetik
    Plant Berlin or superfine hearing-
    protection cotton from Lauscha/Thueringen.
    The ear plugs reduce the noise level of
    104 dBA by 22 dBA, and at level of 89 dBA by
    9 dBA, at  level of 93 dBA only by 8 dBA.
    '"Cotton1  reduces the level of 89 dBA by 14 dBA
    and that of 93 dBA by 15 dBA.  At values
    below 75 dBA the ear plugs, not only do not
    reduce the level, but raise it by means of
    resonance.

    Of importance are the extra-aural noise
    damages; a frequently observed noise symptom
    is the delay of the stomach peristalsis.
    Seamen often complain of digestive problems.
    Also the vegetative nervous system  is
    affected, as well as pulse frequency and
    systolic blood pressure.  Medical research
    shows that the vegetative system does not
    aclimate itself to noise even though it
    can be tolerated as a psychological
    phenomenon.
was conducted for 5 or 6 days in each plant.
The noise level  in the work area is 88 to
107 dB for 3.9 t or - 1.01  minutes and
alternates with pauses in the operation of the
test stand of 1.94 minutes, during which
the noise level  is 68-90 dB.   The noise is
generally of high frequency,  but in some work
areas medium frequency dominates the noise
spectrum.  Workers are affected by this noise
7 hours a day.  The noise  level  exceeds the
limits prescribed by Health Norm 785-69 of
April 30, 1969 by 14-18 dB (see Figure 1).
                                                                  FIG.  1.   Noise Spectrum of Test Stands In an
                                                                           Aircraft Maintenance Enterprise
                                                                  A = ISO  Curve 80
                                                                  (1  -  Test Stand No.  1;   2 - Test Stand No.  2)
    02-005

    Men'shov, A. A.
    Zagurskaya,  L. A.

     Institut Gigiveny Truda  i Profzabolevan iy /USSR/

    Kiev, USSR

    HYGIENIC EVALUATION OF  INTERMITTENT NOISE IN
    TESTING OF AIRCRAFT HYDRAULIC UNITS

    Gigiyenicheskaya Otsenka Preryvistogo Shuma
    pri  Ispytanii Aviatsionnykh Gidroagregatov

    Gigiyena Truda  i ProfessionaI'nye
    Zabolevan iya

    Vol  15 No  10:9-12,  1971
     Noise  conditions  were  studied  in  areas for
     testing  hydraulic aviation  units  in  four
     aircraft maintenance plants.   Noise  meter type
     2203 (Bruel  &  Kjaer) and octave spectrum
     analyzer type  1613 were used  in the  tests.

     The job  requires  working  in a  standing
     position and manual visual  coordination.   It
     also involves  static nerve  stress.   The
     dominant adverse  working factor  is noise.
     Sources  of noise  include the  hydraulic unit
     itself,  the engine and reducer of the test
     stand, and the system  for  loading the test
     stand.  The intensity  of the  noise  in the
     work area depends on the type  of  unit being
     tested and the test conditions.   The noise
     consists of alternating noise  levels of
     various  intensities and spectral  composition,
     thus considered intermittent.  Measurement
 Subjects of  the  study were 6 male workers,
 28-35 years  old, and all worked on the same
 test stand.  All were practically healthy,
 with normal  hearing, and had been on the
 job one to three years.  Figure 2 shows the
 spectrum of  noise to which the workers were
 subjected.   The  test stand consisted of a
 test cubicle and a control console with a door
 outside the  cubicle.  At the control console,
 workers were subjected to a sound level of
 92 dB for 3.02 minutes, then in the testing
 cubicle for  0.42 minutes at a noise level of
 104 dB, and  then to 98 dB for 1.2 minutes at
 the console  wifh the aoor open.  During the
 pause in test stand operation, a noise level
 of 88 dB from adjacent test stands for 2.66
 minutes affected them.
 FIG.  2.   Noise  Spectrum  Affecting  Workers  Tested
 A =  ISO  Curve 30
 (1  -  In  Test Cubicle;  2 -  At  the  Control
 Console  With Door  Open;   3  - At  the  Control
 Console  With Door  Closed;   4 - Noise Level
 During Pause
                                                         62

-------
                                                                                                         02-006
                                             PHYSIOLOGICAL
The following physiological and psychological
measurements were recorded: selected air
audiometry at 125, 500, 4000, and 8000 Hz
and bone audiometry at 4000 Hz; critical
freguency of auditory flickering; performance
in the black-red table psychophyslological
tasks; memorizing numbers; muscle fatigue;
functional state of cardio-vascuIar system by
measuring arterial pressure and pulse rate.
Studies were conducted at the beginning of
work, after 3 hours work and after 30 minutes
rest.

Results showed that auditory sensitivity
thresholds increase no more than 10 dB,
within the limits of auditory adaptation;
critical frequency of auditory flickering
changes from 134 to 120.3 flickers per second;
indicators of muscle fatigue (V. V. Rozenblat
method) decreased from 117.4 to 92.5 per
second; pulse rate decreased from 73.6 to
68.7.   Indicators did not return to original
values  in 30 minutes of rest after 3 hours
work.  No essential differences from base data
were observed for arterial pressure, short-
term memory, or performance in the black-red
table psychophysiological tasks.  Results of
the study prove that the  intermittent noise
prevailing in the testing areas  is
physiologically adverse.
Smitley, E. K.
R i nteImann , W. F.

Michigan State Univ.,
East  Lansing

CONTINUOUS VERSUS INTERMITTENT EXPOSURE
TO ROCK AND ROLL MUSIC

Archives of Environmental Health

Vol 22 No 4:413-420, 1971
 In the past few years concern has risen over
the possible bad effects of loud rock and
roll  music.  A number of recent studies
were made on the effects of rock and roll.
Five types of experimental  approaches were
used.

One method involves measuring the hearing
of people who have been exposed to rock and
roll  music over long periods of time.  A
study  made using this method found that
95? of 42 rock and roll  muscians did not
incur  hearing losses, even  though they had
been  exposed to 105 dB sound pressure level
(SPL)  of music for an average of 11.4 hours
a week for 2.9 years.
Another approach was a histological study of
laboratory animals that have been exposed to
music with a peak  intensity of 122 dB SPL
over a 2 month period of time.  Marked
sensory cell damage was found in the
cochlea.

Measuring high frequency thresholds is a
third approach to assessing the effects of
rock and roll music.  Thresholds were found
for 24 high school musicians and for a 24
subject control group.  Of the muscicians
15% were found to have poorer high frequency
pure-tone thresholds at one or more
frequencies than those in the control  group.

A fourth approach  is to attempt to predict
hearing loss on the basis of damage risk
criteria (DRC).  DRC are the maximum intensity
levels and durations of noise exposure to
which individuals can safely be exposed.
Noise levels of 95 dB are considered
hazardous, while rock and roll music is
usually played from 98 to 108 dB.
Thus, a potentially hazardous situation does
exi st.

A fifth approach is to attempt to predict
hearing loss on the basis of temporary
threshold shift (TTS), or the reduction in
the auditory threshold resulting from noise
exposure provided that thresholds return
to pre-exposure levels in time.
Determinations have been made with the
recommendation that the TTS does not exceed
10 dB at 1,000 Hz and below, 15 dB at 2,000
Hz,  and 20 dB at 3,000 Hz and above.  On a
prediction basis, noises greater than
92 dB between 500 and 8,000 Hz for
a period of one hour wi I I  produce as much
as a 40 dB TTS in the area of 4,000 Hz in
10? of the exposed ears,  no measurable
shifts in another 10?, and a 30 dB TTS in
the remaining 80%.

A study done on the TTS approach found
SPL's as high as 120 dB produced by a
rock and roll band, with  four spectators
sustaining up to a 35 dB TTS following a four
hour exposure.   The conclusion was drawn
than rock and roll  music poses a serious
threat to hearing.

One characteristic of the sound  produced by
rock and roll is that it is intermittent.
The on-time is generally  3 to 5  minutes in
duration,  and the off-time is usually  less
than one minute.   This allows at least
partial  recovery from auditory fatigue.
Continuous vs.  intermittent exposure to rock
and  roll  music, then, should result in
different  TTS's for the respective exposures.
                                                    63

-------
02-007
                                                 PHYSIOLOGICAL
    02-007

    Kryter, K. D.

    Stanford Research  Inst., Menlo Park, CA

    Sensory Sciences Research Center, Zip 94205

    NON-AUDITORY EFFECTS OF ENVIRONMENTAL NOISE

    American Journal of Public Health and
    the Nation's Health

    MAR:38-398, 1972
02-008

Downs, M. P.
Hemenway, W. G.
Doster, M. E.

Colorado Univ., Denver

Colorado University Medical  Center, Denver

SENSORY OVERLOAD

Hearing & Speech News

MAY-JUN:10-11, 1969
    Excessive noise, as everybody knows, can
    impair and even damage the hearing apparatus.
    But noise has other effects, too, and a
    knowledge of these is necessary for a proper
    evaluation of noise.  The effects of noise
    on mental and motor activity and on general
    health and mental well-being are discussed.

    Sudden bursts of noise cause responses  in
    man and organisms that may be designated as
    "arousal1' and 'stress" responses.  These
    are instinctive, and exist for self protection
    in potentially dangerous situations.  However,
    with continued exposure to a certain noise,
    the organism will adapt and cease to show
    an arousal response.  Sudden noises will
    also cause an eye-blink response, but
    this does not cease with continued exposure.
    Years of exposure to steady noise above 110
    dB can cause temporary and permanent changes
    in the size of the visual field, and noise
    above 130 dB can cause (nystagmus and vertigo.
    Continued elicitation of the arousal response
    by noise can become stressful and can cause
    damage to the cardiovascular, gastrointestinal
    and neurological-glandular systems.

    The awakening effects of the noise on sleep
    are related to the effective perceived noise
    level, the meaning of the noise to the person,
    the age of the person, and the stage of sleep
    the person  is in.  The hearing threshold as
    a person goes from  light to a deep stage can
    increase as much as 70-80 dB.  However, the
    awakening reaction to noise that does occur
    does not decrease with continued exposure.
    Individual reactions to and attitudes toward
    noise vary greatly.  Some people can adapt
    to noise and appear to be unaffected by it,
    while those who cannot, suffer physiological
    stress.

    More  laboratory studies regarding  individual
    sensitivity to noise are recommended.  Open
    field studies should also be conducted, but
    with caution, because of the multiple variables
    involved.
A study was made of the effects of amplified
rock and roll music on hearing.  Specialists
point out that sound levels in the music (105-
122 dB) over prolonged periods exceed safety
limits set forth by the Committee on
Conservation of Hearing of the American
Academy of Ophthalmology and Otolaryngology.
They argue that loss of hearing  is too
great a price for the dubious pleasures of
overloading the senses.

It has not been easy to show that ears are
damaged by continued exposure to the blare
of rock and rolI, although it has been
shown beyond doubt that the high noise
levels of gunfire produce permanent damage
to hearing.  Apparently, standard audiometric
measurements do not show hearing changes in
young people exposed to electronic music.
Standard hearing tests are done  in the
frequency range from 250-8,000 Hz.
Damage to the ears from noise exposure such
as rifle fire usually shows up in the area
near 4,000 Hz.  No one, however, has shown
what effects noise exposure may have on
hearing in frequency ranges above 8,000 Hz.

Twenty-four musicians and eleven riflemen
were tested and compared with thirty-six
boys who neither played in bands nor
participated  in rifle team activities.
These young men were given two types of
audiometric tests: (1) a high frequency
threshold test covering the range from
4,000-18,000 Hz and (2) a pure tone
screening test at 25 dB (ISO)  in the
range from 500-8,000 Hz.  In the rock
and roll group, hearing levels at frequencies
above 10,000 Hz are consistently worse than
in the non-exposed group by 10 dB or more.
In the rifle team group, differences of  10
dB or more occurred only at frequencies above
16,000 Hz.

This preliminary study poses many questions to
be answered by more exhaustive investigation.
For example, the audiometer us'ed  (Rudmose
ARJ-4HF) was biologically calibrated on younger
high school students than the seniors who were
tested.  The Means of high frequency thresholds,
even  in the non-exposed, presumably ''normal'
seniors, were much poorer above the 10,000-
12,000 Hz  range than would be expected.  This
could mean that at the present time there  is
                                                         64

-------
                                             PHYSIOLOGICAL
                                                                                                         02-009
great attrition to high frequency hearing
during the high school  years, as a result of
ears being assailed by  loud levels of noise.
Limiting Daily
Exposure Times

  less than:

   2 mi n
   4 min
   8 min
  15 mi n
 1/2 hr
                                                                       hr
                                                                       hr
                                                                       hr
                                                                     8 hr
                                                                 16-24 hr
                                Sound Level
                                  in dBA
                                 115
                                 110
                                 105
                                 100
                                  95
                                  90
                                  85
                                  80
                                  75
                                  70
02-009

Cohen, A.
Anticagl ia, J.
Jones, H. H.

Public Health Service, Cincinnati, OH

1014 Broadway, Zip 45229

''SOCIOCUSIS"  — HEARING LOSS FROM NON-
OCCUPATIONAL  NOISE EXPOSURE

Sound and Vibration

VoI 4 No 11:12-20, 1970
An evaluation  is made of hearing  loss risks
from exposures to non-occupational noise
conditions.  Hearing  loss risks exist in non-
occupational situations such as in using home
power equipment, in recreation, and from
public services  like transportation facilities.
"Sociocusis" denotes noise-induced hearing  loss
with emphasis on everyday noise and noise at
work.  Even  limited exposures to off-job
noises can cause temporary threshold shifts
(TTS) in hearing.  However, even when such
noises are of high intensity, their usual
intermittency and the relatively small daily
total exposure time involved greatly reduce
their threat to hearing when compared to that
of noise at work, which is usually much more
conti nuous.

Noise conditi' "i '"• "ff-jon situations were
compared with quite protective noise limits
(deliberately chosen 15 dBA stricter than the
Walsh-Healey standards for industry).   The
results suggest that people receiving frequent
or protracted exposures in everyday situations
are  liable to some risk of hearing loss.  Even
though daily exposures to everyday noises may
not be a distinct hazard to hearing, they may
increase industrial  hearing loss by making  it
impossible for the worker to find enough off-
job quiet to allow his ears to recover each
evening.

The off-job exposure criteria selected are
shown in  the following table:
Continuous exposure of eight hours to octave
bands of noise in the 75-78 dBA range causes
no significant TTS in hearing at 4000 Hz, the
frequency most prone to noise-induced loss.

Typical sound levels and exposure times,
described below,  may be compared with the
limits in the table above.

Recreational  activities provide the highest
levels found in off-job settings.

Impulse noise, peak sound level in dB, can not
be compared with  levels in dBA.  A relevant
but not particularly protective criterion for
impulse noise exposure has been proposed  by
the Committee on  Hearing and Bioacoustics and
Biomechanics (CHABA) of the National  Research
Council; peak sound level  should not exceed
128-164 dB, depending on the pulse duration
and rise time.  These  limits apply to 100
impulses distributed over periods of 4
minutes to several  hours on any single day.

Music fans who regularly attend rock and  roll
sessions may risk exposures harmful to hearing.
Hazards to band members are even more
significant;  one  study showed the average
playing time of such musicians, both practice
and performance,  was 11 1/2 hours per week.
Both musicians and listeners showed significant
differences in pre- and post-exposure hearing
levels (TTS)  after a 3 hour session at 112 dBA.
(Figure 1).  On the other hand, one study found
that only 2 of 42 rock musicians showed
distinct permanent hearing  losses.   It was
conjectured that  the intermittent nature  of
rock music, with  on-time of 3 to 5 minutes and
off-times of about one minute, allows partial
recovery from the build-up of auditory fatigue.

Average dBA levels found in the cockpits  of
small airplanes could be tolerated, according
to the off-job exposure criteria, for 3/4 hours
per day or 3 3/4  hours per week.  Figure  2
shows the TTS resulting from a comparatively
short flight in a light plane.

Racing motorcycles are potentially hazardous
to hearing even with brief exposure times.

Hearing tests for sports hunters and a control
group of non-hunters show marked difference in
median hearing level  (Figure 3).  The hunter
group consisted of sportsmen who had used
                                                    65

-------
02-009 (CONT.)
                                                   PHYSIOLOGICAL
                              TEENAGE BAND
                              MEMBERS  PLAYING
                              ROCK a ROLL MUSIC
                                           O	O PRE-EXPOSURE
                                           •	• POST-EXPOSURE
     TEENAGE DANCERS EXPOSED TO
        ROCK 8 ROLL MUSIC
                O	O PRE-EXPOSURE
                • - -• POST-EXPOSURE

                112 dBA - 3 HOURS
                                                                         1000   2000  30OO   4000  6000
                                                                           TEST  FREQUENCY  ( Hr>
    assorted ri fles,  shot-guns, and pistols,  most
    of whom had never worn ear protectors.  The
    hunters and non-hunter groups were of  similar
    age distribution,  and the hunters had  poorer
    hearing, averaged across all ages.
                    1000   2000   300O  400O

                      TEST FREQUENCY (Mil
             — Hearing levels for a sport pilot and passenger meas-
       ured just before and l)eiu,een eight to snteen minutes after a
       one-hour flight in a single-engine Cessna tLith cockpit  noise
       levels t drying between  89-91 dBA. Data from PUS sample
       oiwCTuxfon..        Figure 2
    In the home power  equipment and appliances
    category, chain  saws  produce the most  intense
    sound levels:  97-107 dBA.   According  to the
    off-job criteria,  daily safe time  limits are
    4-15 minutes, but  in  fact chain saws are
    usually not used often  enough to pose  a serious
    sociocusis problem.
                                                         Figure 1
                                                                      Figure 3
              JCWO JOOO *000 6000 BOOO  ?SO 5OO 1000

                      FREQUENCY IN HERTZ (Hi)
                                                                                                            1000 4000 «000 1000
Gasoline power lawnmowers (94-94  dBA)  are used
perhaps twice  a  week for 4 months of  the year
in most parts  of the U.S.  Off-job  criteria
suggest limits of one hour per day  or 5 hours
per week.

Home appliances  (77-83 dBA) could  be  tolerated
from 1  1/2  to  5  hours per day, depending on the
sound  level, and evidently do not  pose hearing
risks  unless there is protracted  use  on a daily
basi s.

Public transportation noise exposures of
passengers  of  typical aircraft (77-90 dBA),
subway cars (90-97 dBA), and buses  (78-85) vary
in the amount  of hearing loss risk  because some
means of transportation are used  much more
frequently  than  others.  The worst  problem may
therefore be subways, with a segment  of the
subway riding  public probably exceeding the
off-job criteria limit of one hour  per day.

General environmental noises include  those
radiating from airports and expressways,
construction sites,  and industrial  plants.
The intermittent nature of aircraft flyovers
(87-103 dBA) usually makes them a minimal
hearing loss threat.   Construction  noise levels
(82-98 dBA)  are  more continuous,  can  occur for
periods exceeding the off-job criteria, and
often, although  supposedly temporary,  exist for
several years.   Roadway noise (62-98  dBA) could
be hazardous to  hearing in areas  where heavy
traffic conditions last for more  than  2 to
4 hours per day.
                                                          66

-------
                                                                                                         02-010
                                              PHYSIOLOGICAL
02-010

Spiechowicz, S.

Instytut Naftowy, Cracow /Poland/

Cracow, ul, Lubicz 25a

EFFECTS OF NOISE ON THE PHYSICAL AND PSYCHICAL
EFFICIENCY OF WORKERS

Wplyw Halasu Na Spranosc Fizyczna  I Psychiczna
Pracowni kow

Nafta

Vol 27 No 8:11-12, 1971
The Warsaw Polytechnical Institute prepared an
exhibition on the topic of noise.  Various
kinds of equipment, abatement devices and
instruments were displayed.

The workshop on the Psychology of Work at
the Petroleum Institute in Cracow carried out
noise measurements at the oilwells of Pi I.
In the 'Babilon" Mine in Pi I  noise levels
ranged up to  114 dB when drilling machines
were operated, one type even reached 129 dB.
The noise levels in the "New Tavern" Mine
(Nowa Kurczma) ranged up to 124 dB when the
same type of drilling machine was used.

Such high noise  levels are not only hazardous
to the workers' ears, but also are harmful to
the nervous system of the workers.  Noise
can cause headaches, fatigue, distraction,
loss of concentration and neurosis.

On AUG 21,  1959, the Council  of Ministers
passed a norm establishing 90 dB as the
permissible noise  level in work places.
Polish norms  specify the following base  noise
levels:
1.  resi dences            25 dB
2.  stai rcases            40
3.  offices               30
4.  hospital rooms        25
5.  construction offices  50
6.  precision offices     50
7.  factory workshops     90

Noise  is a subjective type of annoyance and
affects people differently, both physically
and psychologically.  The effects may become
more obvious in one person than in another.
However, gradually noise affects everyone,
and this is especially evident in the
production output of workers.  It is, therefore,
recommended that people working in noise
exceeding 85 dB should be sent for prophylactic
purposes for a rest in trie country, in order
to restore the;r psychological state of mind,
rebuild physical strength ana regenerate
the whole nervous system.
02-011

Thackray, R. I.

Civil Aeronautics Inst., Oklahoma City, OK

Box 25062, Zip 73125

SONIC BOOM EXPOSURE EFFECTS I 1.3: STARTLE
RESPONSES

Journal of Sound and Vioration

Vol 20 No 4:515-526, 1972
Somatic reactions to impulsive acoustic stimuli
will cause startle responses which consisr of
the startle reflex, the orienting response, or
a combination of the two.  Because of their
similarity, they are often confused.

The startle reflex is prirr,aiily a muscular
response where the complete reaction consists
of  involuntary contractions beginning with
an eyeblink ~-.nd rapia'v prog' e ~-s i 'ig to the
legs.  The time ivs-t^i^ ^f f e tola! response
ranges from 0.3 seconas for a ml id response to
1.5 seconds tor an inter se '"eaction.  There
is also a greaT increase  in autonomic and
central nervous system activity.   The eyet ' nK
response is the only reflex in The startle
response that does not habitats.

Stimuli of medium  intensuv are I'l-elv tc evoke
the orientation response.  T'ie most
characteristic reaction is a turning of +he
body or head toward fhe source.  Suppression
of activity, increased receptor rensitiviiy,
and increased EEC activity also cccu' .

Startle response fends to ipipo'r performance,
while the orienting response merely serves to
alert.  Tasks requiring precise arm-hand
coordination are generally inpaired tor only
a few seconds which suggests that the major
cause of the disruption is +he muscular reflex
response associated virh startle.

Tasks involving complex perceptual and or
cognitive processes may be impaired for long
periods.  Significant impairment may persist
for up to th ' rty seconds.  impulsive t>olse
produces impa i ; nenf by distracting atten : , on
from the central rask.

Acoustic stimuli t^o to  i mpe i •* performance at
levels abcvt^ --.r.r- ;-,'marely 95 dB,  But have
little <2ffeci  01  increase performance below
4 ", ; s  level.  Whether this value also corresponds
to the threshold for startle ref!e
-------
                                             PHYSIOLOGICAL
vasoconstriction which are approximately
proportional to the increase in scund pressure
level.  Startle or defensive reflexes are
accompanied by vasoconstriction in the head
region as well as in peripheral regions.
Orienting responses are accompanied by
peripheral vasoconstriction, but vasodilation
at the head.  The predominant  initial
heart-rate change associated with  the orienting
response is deceleration, while startle appears
to evoke an initial  accelerative response.

Intensity is not the only parameter in impulsive
acoustic stimuli.  Rise time, as well as
overpressure,  is a major determinant of
loudness.  Both the behavioral  and physiological
aspects of The orienting response  n't I I  habituate
completely with repeated stimulation—possibly
after 10-30 repetitions.  Even  a small  change
in the characteristics or the stimulus ma/
result in a partial  or complete reappearance
of the response.

Tracking performance has been  investigated
following bursts of  105-117 dB  white noise
presented against background noise of 45-34
dBA.   Performance impairment was least wi th
the highest level of background no'se arid most
when  the noise was at room level.   These -esults
coiflict with  other findings and underline the
need  for further research:  Subjects with the
greatest skill  levels prior to  presentation of
impulsive noise display the least  Impairment.

Systematic research  is needed on the patterns
of muscular, autonomic, and subjective response
to impulsive stimuli.   Subjective  measures
(i.e., rating  scales)  should not serve as
substitutes for objective indices  of stai—le
at the present time, but it would  be useful
to obtain the  intercorrelations between
subjective and objective indices ir  order to
determine +he  extent to which such measures
could s'jbsti'J.'t  lor objective  one0-  in  future
research.
02-012

Karagodi na, I.  L.
Soldatkins, S.  A.
Vinokur, I. L.

Moskovskiy Nauchno-lssledovatel'skiy  Institut
in". T.  F.  Fri °mana
MO..COW  Sr .,• (-1' T i _- Research Inst of Hygiene
/USSR/

EFFECT  OF NOISE PRODUCED BY AIRGRAFi ON THE
POPULATIONS RESIDING  IN THE VICINITY OF AN
AIRPORT

VI yaniye Aviatsionnogo Shuma  na Naseleniye,
Prozhivayushcheye v Rayone Raspo lozheniya
Aeroportshch

Gigiyena i Sanitariya
A study of aviation noise was conducted at 9
busy airports.  Ranges for the dispersion of
noise at a fixed  level for various types of
airplanes were measured, a public evaluation
was performed, physiolcgicaI  testing on the
effect of noise was done, and safe noise  levels
based on the researcn were established.

During plane landing, noise  levels of 85 dBA
and higher were found to range from 9 to 19 km
away from the noise source.  Noise ranges for
aircraft takeoff are much smaller:  0-12 km at
85 dBA and 9-25 km at 75 dBA.  The distance
depended upon the type of aircraft used.  The
'noise radius'1 therefore j/tends quite far for
relativeiv intense snund.

Public reaction to aircraft noise was
researched by sending questionnaires to 2,000
people in 22 urban and rural  regions, all
located within a 40 km radius of an airport.
Adverse public reaction was found to be a
function of the following factors:  noise
intensity, popu1at ion age group, and years
of habitation near the airports.  Complaints go
up as noise level  and ago increase, but
diminish as habitation near the airports grows
longer.  Physiological investigations of the
population revealed that those living 1 to 6
km from airports suffered 2 to 4 times as much
otorhinolaryngological disorders as did those
living 40 km away.

Investigations ntado on the effect of aircraft
noise upon the human central  nervous and
cardiovascular systems revealed significant
results for noise of 90 dBA.   To study reaction
time, noises ranging from 50 to 90 dBA at a
rate comparable
per hour were ex
booths.  Reactic
s i qnaIs va r i ed r
noises of 60 to
per hour, as com
exposed control
(1C overhead f I  i
a difference in
An even greater
occurred when tt
was increased to
indicate that wh
dBA have a negIi
nervous system,
to 10-20 flights passing over
posed to people  in  isolation
>n time to visual and audio
inly slighfly1 (1-10  msec) for
80 dBA if ID and 20 "f I ights"
ipared with the si lence-
group.  Noise  levels of 90 dBA
ghts per hour),  however, caused
reaction time of  19-29  msec.
difference of 30-36 msec
e number of noises  at 90 dBA
> 20 per hour.  These results
i le noise levels of 60  to 80
gible effect on  +he central
90 dBA affects  it adversely.
Effects of noise on the cardiovascular system
were also studied.  Plethysmograms did not
indicate much change due to noise  levels, but
pulse rater, decreased by 231? at 90 dBA.

The  results of this study  indicate that the
restrictions put on noise  levels  in other
countries are not  low enough.  Their  standards
set  aviation noise at a maximum of 100 dBA
during the day end 90 dBA  at night.   The
authors recommend  a tightening of  restrictions
to £5 dBA in the daytime and 75 dBA at night.
                                                     68

-------
                                                                                                         02-013
                                            PHYSIOLOGICAL
02-013

Laudanski,  A.
Chotecki, B.
Sulkowski,  W.

Szpital  im. Pirogowa, Lodz 2 /Poland/
Oddzial  Laryngologiczny

u I  . Wschodnia 61  m.5

On:  EFFECTS OF FACTORY NOISE ON THE EQUILIBRIUM

Wplyw halasu fabrycznego na narzad rownowagi

In:  Malecki, J., Bardadin, T.,
Pamietnik XXVI I  Ziazdu Otolaryngologow
Polskich W Katowicach 1968 g.

Warsaw, Panstwowy Zaklad Wydawnictw Lekarskich,
1970, 352p. (p.  80-83)
The Department of Laryngology of the Pirogow
Hospital in Lodz carried out investigations to
determine the effects of noise on equilibrium.
Tests were administered to 68 persons who at one
time or another had suffered from equilibrium
imbalance.  Of these, 42 reacted rather intensely
to noise.  For control  group purposes 12
healthy individuals were tested.  Brief noises
emitted from a weaving mi I I  were used to
determine their effects on workers suffering
from ear ai Iments.   The results show that noise
exposure caused vertigo, equilibrium imbalance
and other vegetative disorders in some of the
workers.  The most  common reaction observed was
equilibrium difficulty.  The noise levels during
the experiments reached 95 dB.

The experiments consisted of audiometric
measurements, the Barre and  Romberg statistical
tests for equilibrium,  the Unterberg and
Babinski-Wei Ie kinetic  tests, the Ha I I pike
caloric tests and the rotation  test.   The
duration of all  the tests was between 10 to 20
minutes, depending  on the patient's reaction.

Out of the 12 healthy individuals one showed a
strong reaction  to  the  rotation test.   However,
none suffered from  equilibrium imbalance after
noise exposure.

The 68 patients  suffered from some of the
following ailments:   skull  injury, Meniere's
disease, ear infection  and deafness.   The most
sensitive were those patients who had taken
streptomycin  and had head injuries or Meniere's
disease.  All  authors concur that noise
definitely  affects  the  inner ear and  causes
i rritabi Iity.
Bystrzanowska, T.
Caputa, T.
Domanski,  R.

Akademia Medycyny, Katedra Laryngologii,  Warsaw
/Poland/

Marszalkowska 68/16

On:  EFFECTS OF NOISE ON THE HEARING OF BLIND
WORKERS

Wplyw pracy w halasie na narzad sluchu  w
niewi domych

In:  Malecki, J., Bardadin, T., Pamietnik
XXVII Ziazdu Otolaryngologow Polskich w
Katowicach  1968  r.

Warsaw, Panstwowy Zaklad Wydawnictw
Lekarskich, 1970, 351p. (p. 18-21)
The Department of Laryngology of the Academy of
Medicine  in Warsaw conducted a study to
determine whether noise affects blind workers
more than normal workers.  The test group
consisted of 243 individuals ranging from 16 to
69 years of age; 99 of the group were women.
The biggest age group, from 20-30 years old,
contained 91 persons, the smallest group
contained 12 persons.

Reason for blindness fell into three categories:
1) congenital, 2) through illness and 3) through
acci dent.

About one third of the group had some degree of
hearing  Ioss.

The first test showed that the noise level  in
the work area  in which the blind were employed
ranged from about 80 to  103 dBA.

The next  step was to determine to what extent
the blind can to Ierate noise in their work,
when  it  becomes subjectively annoying and when
actua My tiring.

Fatigue  was felt by 20.9% of the workers.
Age played no major role  in the complaints.
However, women seemed to  be more affected by
noise than men.

LaryngologicaI examinations showed that  10$ of
the workers manifested otoscopic changes such
as scars or perforated ear drums, especially
workers  who had been born blind.


Below is  a chart showing the percentage of the
whole group  that had hearing loss,  as well  as
the similar percentages of various  sub-groups.
                                                    69

-------
02-015
                                                 PHYSIOLOGICAL
                                               53%
31%
X§S
;A^V
SiSsJ




55%
__,
	 .
U___j
.

•'/"





x%


* : -
M
•-y/.
//'//
' s/S
30%
\\\
"NvNs






15%


29%
r~
^ 	
zr^r~.

\\
\\ Xs-

55%
^
'x
^
!:i';;
•:ii!
ii ''
' !'
fry
^'/.
////'
fa'.'
      K.  M.

R = Total  group
K = Women
M = Men
                    U.  W.  Cti
                                ^0 30  40  50  60  >60
                           Cause of Bl i ndness:
                           U = Accident
                           W = Congenital
                          Ch = Through sickness
                       20-60 = Age "~ange
    02-015

    Nagata, Y.

    Institute of National Public Health /Japan/

    On:  PHYSIOLOGICAL EFFECTS FROM INTERMITTENT
    NOISE BY SEX AND AGES

    Kanketsusei-soon ni Tai  Suru Shinshm Hanno
    de no Sei to Men rei no Eikyo

    Nippon Kooshu Eisei Zasshi

    Vol 18 No 10:508
During the 90 minute periods, continuous
recordings of eIectrodermogram reaction (GSR)
and finger plethysmogram were taken.  The total
number of  leucocytes, acidoocytes, and basocytes
in venous blood were measured 30 minutes before
and immediately after the experiment.
Quantities of adrenalin, noradrenalin and
uropepsin  in the urine were measured 30 minutes
before and 120 minutes after the experiment.

The results were as follows:

1) Regardless of sex and age, degree of
discomfort was higher when the noise level  was
85 dBA than 70 dBA.

2) Regardless of sex and age, ranking of
discomfort from intermittent noises, classified
by the noise types, was arranged in decreasing
order:  jet noise, pile-driver noise, tram
noise, and pink noise.

3) Except for electrodermogram reaction (GSR)
and change in pulse frequency, the greater
physiological effects were  in females and in
younger subjects.   Effects  included:  higher
frequency of pulse contraction in fingers,
increase  in total   leucocytes, decrease in
acidocytes and basocytes, and increase in
adrenalin, noradrenalin, and uropepsin in the
uri ne.

4) The GSR frequency was higher in men and older
subjects than in women and younger subjects.

5) The pulse frequency change was higher in
younger subjects.
    For the firs"" time in Japan,  an experimental
    test on physiological effects of intermiltent
    noise was carried out by sex  and age with 10
    men and 10 women as subjects.  Five men and
    five women were in their 20fs and five men and
    five women were in their 40's.   Men and women
    carried out their normal light mental  tasks
    during the 90 minutes exposure to intermittent
    noise in a sound absorbent room.

    Tape-recordedd noise of the following types was
    used in separate trials:

    1) 60 seconds of jet noise once every five
    mi nutes;

    2) 20 seconds of noise from freight and
    passenger trains crossing an  iron bridge; once
    every f i ve mi nutes;

    3) Pile-driver noise putses every second for
    7 minutes, followed by a 3 minute rest interval;

    4) In contrast to above intermittent noises,  the
    pink-noise was played continuously in the fourth
    trial.

    The noise levels at the subject's ear were
    adjusted to 70-85 dBA for trials 1-3 and fo
    50-60 dBA for the pink noise.
02-016

Cottereau, P.

Ecole Nationale Vetermaire de Lyon /France/

2 Qua! Chaveau, 69 Lyon

SONIC BOOM EXPOSURE EFFECTS I 1.5: EFFECTS
ON ANIMALS

Journal of Sound and Vibration

Vol 20 No 4:531-534, 1972
The pressure waves produced by supersonic
aircraft cause variation of pressure on and
in the ground which are audible as the sonic
boom.   The noise can influence the behaviour
of farm and wild anima Is while the variation
of pressure in itself could eventually cause
physiopathological disorders.

The evaluation of effects of sonic booms on
the hatchability of chicken eggs was studied
at White Sands F'roving Grounds.  The particular
                                                         70

-------
                                                                                                         02-017
                                             PHYSIOLOGICAL
set of eggs exposed for the full  period
received over 600 booms.   It had  a hatch of
84.3? (control  84.2/6).   An ex+ensive hatching
failure of Dry  Tortugas Sooty Terns has been
found.  Two reasons as  to the effects of the
booms were suggested; death of the embryos
after abondonment of the colony by the terns
in panic flight after exposure, or physical
damage to eggs  not covered by a sitting bird
at the time of  the boom.

Investigations  on effects of sonic boom
(average 72 N/m2, maximum 265 N/m2) on farm
animal behaviour and performance were made in
1966 at Edwards Air Force Base in California.

The behavioural reactions to the sonic
booms were considered minimal.  Occasional
jumping, galloping, bellowing, and random
movement were among the effects noted.  The
poultry showed  more response than the  large
animals, especially  in the early stages of
the tests.  Occasional  flying, running, crowding
and cowering were noted.

French Army dogs subjected to sonic booms with
high overpressure during focalization have been
studied.  A minor effect on the cardiac
frequency and on the dogs' behaviour was found.
Certain dogs became frightened, fled and
sometimes became aggressive.

Mink  reactions to sonic booms have received
more  attention than  reactions of other animal
species possibly because these animals are
known to be rather sensitive to unusual sounds.
The  responses to the booms have been reported
as similar to  responses to truck traffic,  snow
plows, barking dogs and mine blasting noise  in
the  area.

Differences  in boom  intensities  (average  72
N/m2, maximum  96 N/m2) had no  effect,  repeated
booming produced no  signs of  increased
excitability and reproduction  in boomed and
non-boomed mink was  normal.

Wild  deer  studied at Eg I in Air Force Base  showed
no apparent response to high  level sonic booms.
Animals in the London Zoo were observed in
1968  during a  short program of sonic booms over
London.  Except for a smaI I group of young
chimpanzees, which showed a tendency toward
fright, the reactions of the zoo animals were
negligible.  Sonic booms of around 60 N/m2
caused a slight startle effect among herds of
reindeer, but only exceptionally were on-going
activities interrupted.  As boom  levels
increased up to 200 N/m2 the reactions became
more  noticeable but none of the  lying or resting
animals arose.

Only one sonic boom has been examined  in detail.
In this case, a boom of an approximate
overpressure of 100 N/m2 gave an overpressure
of 1 N/m2 at a depth of 15 m in the sea.  A
single fish did show a brief slowing of
heart-rate (bradycardia), immediately after
the arrival of  the boom.  However, fish
frequently respond similarly to other sound
stimuli, and in particular to sounds generated
by ships.
Studies have been conducted where the effects of
sonic booms on chick embroyos during hatching
are studied in terms of embryo death or
congenital malformation.  Experiments were
carried out with  increasing boom  intensity
(100 N/m2, 300 ms duration; 500,  300; 1500,
300, etc.).  Chick embryos  in hatching which
were exposed to three sonic booms every morning
and three every evening every day (100 N/m2,
300 ms; 500, 300; 1500, 300, 3000, 300) were
not affected.  Chicks from +hese  eggs were
normaI.

Concerning wild animals the following statements
may be made with  a degree of confidence:
(1) sonic booms of overpressures  around 100 N/m2
have no direct, acute effects upon wild mammals
or birds; (2) sonic booms of extreme
overpressures (above 20,000 N/m2) may have the
potential to crack bird eggs, but the question
awaits an adequate experimental test; (3)
chronic direct effects on wild animals have not
been investigated, but no significant effects
of this kind are  presently foreseen; (4) the
disturbance effects of sonic booms of
overpressures around 100 N/m2 on  wild mammals
are probably insignificant, but the responses
of a much greater diversity of species should
be studied.
 02-017

 May,  D.  N.

 Southampton  Univ.  /England/

 Institute  of Sound 8,  Vibration  Research
 University of  Southampton  S09 5NH

 STARTLE  IN THE PRESENCE  OF BACKGROUND NOISF

 Journal  of Sound  & Vibration

 Vol  17 No  1:77-81, 1971
 Sudden, or  impact,  noise causes a startle
 response  in humans  and may also cause startle
 induced accidents.  Noisy sonic booms are
 examples of impact  noise which can disrupt
 the domestic and working environment, as well
 as quiet environments.  A question arises as
 to whether background noise inhibits or
 facilitates the startle response in humans
 when startle noise  occurs.

 The arguments for inhibition of the startle
 response by background noise are based on a
 hypothesis of auditory and other masking.  The
 impact of the startle noise is theoretically
 lessened in effect  in the presence  of steady
 background noise.

The arguments  for facilitation are  based on
 findings by Hoffman  and Searle that backgrounc
noise  increases startle in  rats.  This is
                                                    71

-------
03-001
                                       PHYCHOLOGICAL & SOCIOLOGICAL
    possibly true because startle is a response
    to a potentially dangerous stimulus,  and
    could be greater in a stimulus of given
    intensity the more inaudible (and difficult
    to interpret) a background noise can  cause
    the stimulus to be.

    Since an objective of the study was to begin
    to assess a worker's susceptibility to sonic
    boom accidents derived from involuntary limb
    movements when he  is ^tarMed, the indicant
    of startle used was a measure of control
    precision performance in the seconds  immediately
    foMorfing an impulse.  A pursuit tracking tasK
    was devised for the experiment.

    The background noise used was essentially
    white noise of 72 or 84 dBA; without  it,
    there was a general background  level  in the
    room of 45 dBA, which in itself was cr     'ere
    a Dackground level.  The four startle     iu I I
    were noise bursts of 105, 112,  114, or 117 dB,
    with a duration time of 40 IDS.  Tne single
    starfle stimulus was applied at the 4 minute
    "iark at a point in the task cycle that was
    identical for all  subjects, the instant at
    which the task cycle was mastered.

    Startle was defined operationally as  hand
    acceleration measured from positive peak to
    negative peak  in the task cycle immediately
    following the  impulse minus that in the
    task cycle immediately before the  impulse.
    The task cycle was 1.8 sec.  A period of
    essentially this length has been found to be
    of interest in evaluating the effects of
    startle on control  precision tasks.

    For startle, the effect of the background
    levels was as  follows:
                         TABLE 1
Background level  (dBA)
1 Startle1
                             45
                            2.78
 72
1.62
                                        0.65
    A significant value was obtained from the
    results,  indicating that background noise
    does  inhibit the starfle response in humans.
    Conversely, the quieter the background, the
    greater the startle amplitude will be.
                             03-001

                             Lorenz, W.

                             Martin  Luther Universitaet, Halle-Wittenberg
                             /East Germany/

                             Halle-Wittenberg, Leninallee  18
                             East Germany

                             AUDIOLOGICAL  INVESTIGATIONS OF THE MASKING
                             EFFECT  OF AVIATION NOISE

                             Audiologische Untersuchungen Ueber den
                             Maskierungseffeet Durch Fluglaerm

                             Monatschrift fuer OhrenheiIkunde und Laryngo-
                             Rhinologie

                             Vol 103 No 110:438-44, 1969
A partial  review of the literature on speech
interference level  is given.   The work falls
mainly into 3 categories:  1)  differences in
the required amplitude of  speech under varying
noise conditions (20 dB over  various aircraft
noises, 40 dB under the noise of a compressor)
2)  Characteristics of the masking effect itself
(for example, linear up to 90 dB, irregular
thereafter; degree of masking by low and high
frequency  tones, both complex and pure).
3) the degree of masking permissible under
various communication condition (for example,
normal conversation and traffic).

Two sets of experiments were  performed.   In
the first  the noise of 2 sports planes and
a helicopter was compared  with white noise by
determining syllable Intel IigibiIigy at a noise
level of 95 dB and speech  level of 90 dB.

Intelligibility with the 3 aircraft noises was
about 90%  and with white noise about 66%.

In the second experiment 3 hearing protection
devices replaced the white noise.  The aviation
noise was  110 dB and the speech level was 95 dB
in one test and 100 dB in  the second test.
Intelligibility proved to  be  about the same with
and without the protection devices.
                                                                03-002

                                                                Von Gierke, H. E.
                                                                Nixon, C. W.

                                                                Aerospace Research Labs., Wright-Patferson AFB,
                                                                OH

                                                                HUMAN RESPONSE TO SONIC BOOM IN THE LABORATORY
                                                                AND THE COMMUNITY

                                                                Journal of the Acoustical Society of America

                                                                Vol 51 No 2:766-782, 1972
                                                         72

-------
                                                                                                         03-003
                                   PSYCHOLOGICAL & SOCIOLOGICAL
Present day estimates regarding the
acceptabiIity of sonic booms by man are
derived from various observations,
overflight programs, and experimental
field and laboratory studies conducted
both within and outside the United
States.  The loudness and annoyance of
individual  booms and their dependence
on the boom overpressure and pressure-time
function as well as the complex reaction
of individuals, groups, and communities
exposed to sonic booms of varied magnitude
and frequency are discussed.

The few experiments available proving that
even sonic booms of the maximum intensity
presently feasible do not produce direct
medical  injury are described.  Based on
the integrated body of results of recent
physiological, psychoacoustic, behavioral,
and sociological studies in various countries,
estimates of the effects and acceptability
of regular, frequent supersonic commercial
overland flight schedules are presented and
discussed in terms of aircraft noise
pollution in general, and of potential
certification of aircraft with respect to
noise and sonic boom.

Findings support the current policy that
commercial  supersonic transport aircraft
will  not be permitted to fly over the
United Slates unless and until the noise
factors are brought within acceptable
I  imits.
03-003

Richards, E. J .
Rylander, R.

Loughborough Univ. /England/

SONIC BOOM EXPOSURE EFFECTS III: WORKSHOP
PERSPECTIVE

Journal of Sound and Vibration

Vol 20 No 4:541-544
The exposure to sonic booms is a new facet
in the environment.  The most reactions in
man after exposure to the sonic boom were
identified by the workshop as startle, sleep
disturbance and annoyance.  It was pointed out
that there are other stress reactions such as
increases in the excretion of stress hormones,
cardiovascular, gastrointestinal and central
nervous system responses.

The commonly used expression "startle" was
found to be poorly defined and often confused
with orienting responses.  It was  considered
essential  to develop criteria to distinguish
between startle reflexes and orienting
responses, since their effects on  performance
could be quite different.   Minor effects on
performance were reported  to occur at indoor
boom peak overpressures as low as  6 N/m2
but these appeared more likely to  have
resulted from the orienting response rather
than the startle reflex.   Momentary impairment
of performance on complex  perceptual  motor
tasks may occur after exposure to  booms
of moderate peak overpressure, but is less
likely to have significant effects on
comparatively uncomplicated tasks  such as
dri ving.

The effect of the sonic boom on sleep was
considered to be of great  importance.  Several
studies show that sleep is disturbed at boom
overpressures around 30 N/m2 under laboratory
con d i t i on s.

Data so far accumulated indicate the presence
of groups of high sensitivity or risk in the
population, notable elderly people or persons
with a neurotic predisposition.  Concerning  day
flights estimates of the number of day sleepers
in different communities were considered
essentiaI.

In the nominal peak boom overpressure
range of 60-100N/m2 the individuals might hear
fewer booms than they are  exposed to.  Booms may
be masked by background noise or decrease below
perceptible  levels when penetrating through
structures.

The animal reactions encountered after exposure
to sonic booms seem to be limited to short
periods of alerting and orienting responses.
The workshop agreed that results from studies
on domestic or semi-domesticated animals were
relatively conclusive but  additional studies
wou I d be requi red.

A general conclusion reached by the group
working on structures was  that damage to primary
structures in buildings in good condition is
not to be expected.  The type of damage that
occurs  is mostly superficial and often connected
to already existing strains in the structure
itself.  Although the damage  in itself  is
technically unimportant, its psychological
consequences in terms of a criterion  for
annoyance reactions should not be
underestimated.

Based upon the available information on boom
effects in the different areas of  concern in the
workshop the following suggestion for general
sonic boom exposure criteria for outdoor
reactions has been compiled.  Special caution
should be exercised concerning the exact
classification of startle  because this
reaction has shortcomings  in terms of
def i n i t i on.

The conclusion was that whereas the nominal
peak overpressure would be adequate for certain
types of responses, the pressure rise time,  the
dBA fast  level or other technical  parameters
might be more suitable for other types of
effects.  In order to facilitate the comparison
                                                     73

-------
03-004
                                       PSYCHOLOGICAL & SOCIOLOGICAL
     between  results  from different research projects
     the need  for a common reference noise signature
     was expressed.   This could be  in the form of
     either a  burst of white noise or some other
     sound and should be included in all human
     experi ments.

     The nature of the vibrations of loose objects,
     particularly the secondary response, and the
     method by which  such response creates sound from
     shelves,  tables, etc., should be examined.
     There is  some evidence that aural  stimuli
     supported by visual stimuli, for example,
     amplified apparent movements by window
     reflections can  create fear and annoyance.

     Concerning field studies, the opportunity
     shoulc' be taken to perform studies  in areas
     where sonic booms occur regularly and are
     experienced as part of normal daily life.

     A  problem  deliberately avoided during the
     discussions was  how scientific information
     concerning  sonic boom effects  should be
     conveyed  to the  decision-makers in  society.
     The formation of representative groups with
     sufficient  technical expertise may  provide
     an alternafive to the situation in  which
     scientists  feed  information  into a
     bureaucracy which processes  data and forms
     decisions by  its own unknown standards.
A concurrent sociological  study masked a study
of general attitudes toward living conditions;
one of the problems here was the variety of
Italian words to express degrees of irritation.
It is noted that the results may be due either
to inadequacies in the questionnaire or
to exposure itself.

The following observations were:

1) With the exception of public places, all
sources of noise were noticed more by the
citizens of Stockholm than Ferrara; in the
case of motor vehicle noise, the rates were 92
and 63$, respectively.

2) Of those who noticed traffic noise, the
respective percentage of those who were
disturbed by it were 61 and 49.

3) Of those who felt themselves disturbed, the
percentage of those feeling greatly disturbed
were 23 and 21!?.

4) Of all respondents in Stockholm, 10% thought
their neighbors were probably disturbed by
traffic noise,  in Ferrara, 59%.

It is concluded that "data obtained from
annoyance studies  in one country are valid
in other countries without corrections.'1
     03-004

     Jonsson,  E.
     Kajland,  A.
     Paccagnella,  B.

     ANNOYANCE REACTIONS TO TRAFFIC NOISE  IN
     ITALY AND SWEDEN: A COMPARATIVE STUDY

     Archives  of Environmental Health

     Vol  19 No 11:692-699, 1969
     A  comparative  study was made of subjective
     reactions  to traffic noise  in Swedish and
     Italian  block-style muItifamily dwellings
     situated on either side of  highly traveled
     urban  streets.   Variables such as road width,
     walI thickness,  year of construction and
     traffic  composition are described.

     The  dBA  scale  was preferred to other more
     sophisticated  predictive  methods.  Measurements
     inside residences were made with windows open
     and  closed, and  a standard  deviation was
     calculated.

     For  all, but one, vehicle type and for windows
     open and closed, the mean values  in  Italy
     exceeded those in Sweden; for passenger cars
     the  differences  were 8.0  and 5.4 dBA for
     closed and open  windows,  respectively.
03-005

Mori , S.

Ritsumeikan Univ. /Japan/

13-84,  Kihata Minamiyama, UjI  City,
Kyoto

EDUCATIONAL ENVIRONMENT

Kyooiku Kankyoo

Koogai:  Yosoku to Taisaku

Tokyo,  Asahi Shimbunsha, 1971, 291 p.
(p.  145-164)
The Japanese Ministry of Education made a
nationwide survey of educational environments
in public elementary and middle schools.  The
survey covered 8,236 schools  (23.3? of total
schools  in Japan).  Many had  noise, air
pollution and traffic safety  problems.  The
sources of noise are, principally, automobiles,
but also jets, trains in the  cities, and
factories.  This survey was based on the
teacher's view of the educational environment
in the 2,210 schools affected by noise.

The survey of students' opinions of the
educational environment included 108,000
                                                         74

-------
                                                                                                         03-006
                                    PSYCHOLOGICAL & SOCIOLOGICAL
7th grade students in 623 schools in 13
major cities.  About 30? answered that
the environment in their school vicinities
was 'bad" or 'very bad."  Noise was particularly
mentioned, with street noise as the worst
source of pollution.

The Osaka Educational Research Institute
measured actual noise levels in "noisy"
classrooms (Group A) and 102 "quiet"
classrooms (Group B) in 67 schools
in Osaka.  Mean values of noise levels for
Group A was  in the 58.8-60 dBA range with
windows open and in the 54.6-56.8 dBA range
with windows closed.  This means that 80% of
the "noisy"  classrooms exceeded the
environmental standard (55 dBA) designated
by the Ministry of Education.
School children  in the 5th and 6th grades in
40 classrooms were questioned on noise, with
1,148 from 'noisy" and 1,552 from "quiet" rooms.
Noise bothered 50? of them.  Only 6.3? said
noise dtd not bother them.

The  questionnaire  responses showed the following
problems  in the  students:

Emotional  irritation:
(1)  can not  listen to teachers calmly;
(2)  become  irritated or angry;

Motivation:
(1)  wish that the class period were over soon;
(2)  do not want  to study any more;
(3)  feel  like shouting;

Disturbance of mental work:
(1)  often make mistakes in mathematics
problems;
(2)  spend more time on solving problems;
(3)  can not remember once memorized Japanese
characters  (or difficult to remember);
(4)  while answering teacher's question,
forget the  last  half of answer and therefore
can  not give a complete answer;
(5)  can not complete thoughts in composition
class;
(6)  find  it difficult to grasp contents in
reading;

Speech interference:
(1)  misunderstand what teachers are saying;
(2)  can not hear classmate's answer to a
question from the teacher;
(3)  have to shout to the teacher for him to
hear;
(4)  during class period,  classroom naturally
becomes noisy;

Physical  influences:
(1) when concentrating on  listening,  become
absent minded or get  headache;
(2)  become fatigued early;
(3) become sleepy and distressed;
(4) experience ringing in  the ears.

The Osaka  results indicate a clear correlation
between noise level  and speech  interference.
In teaching, normal  noise  level  of a  teacher
 in a normal classroom measured at a distance
of 6 meters from the teacher is 65-66
dBA.  Therefore, the noise level  in the
classroom should be below 60 dBA, but since
46? of the total city classrooms have noise
 levels of more than 60 dBA, the teachers
must raise their voices up to the 70 dBA
 level.  The teachers must therefore do a great
deal of shouting, which can be both fatiguing
and emotionally upsetting.

A study by Kyoto City of 572 students in the
5th and 6th grades found a serious effect of
noise on mental performance (calculation,
memorization, creative work and understanding).
The Uchida-Krepelin census method was used in
this test.  The study reveals that noise
 increases mistakes and lowers the beneficial
effects of recess.  Noise as a causative factor
 in mistakes was 1.3 times more important
than other factors, and the higher +he noise
 level, the greater the number of  mistakes.
The study also revealed that when there was
excessive noise in the outdoor recess
environment, the recess was only  92? as
beneficial as a recess in a quieter setting.
There was also a trend of increasing number
of mistakes after recess.  Working efficiency
at first slightly rose (this was  considered
to be the result of concentration on mental
work) but decreased drastically after 25
mi nutes.

Prof. Tama of the Osaka Educational  University
studies noise effects on students'  mental work
in the classroom by reproducing taperecorded
automobile noise.  The speaker was suspended
from the classroom ceiling, and produced a
 level of 70 dBA in the room.   Children in
another classroom with a noise level of 4?
dBA performed the same tasks.  The results
reveal that for such complicated menial work
for children as judgement, reasoning,
composition and reproduction of numbers in
mathematics, students in the 70 dBA
classroom scored much lower than  those in
the 45 dBA classroom.  Only for the
reproduction of Japanese characters were
the scores for the two rooms comparable.

The Tokyo Anti-Pollution Study Committee for
Elementary and Middle Schools made a similar
study of 18,000 students in 651 schools
throughout the country and reached similar
cone I us ions.
03-006

Stephens, S. D.

Medical Research Council,
Cambridge /England/

HEARING AND PERSONALITY: A REVIEW

Journal of Sound and Vibration

Vol  20 No 3:287-298, 1972
                                                    75

-------
03-007
                                       PSYCHOLOGICAL & SOCIOLOGICAL
    Two groups of  personality  inventories have
    been  repeatedly found to  influence a variety
    of auditory measures.  These groups may be
    referred to as the  introversion extroversion
    group of measures and the  anxiety group of
    measures, respectively.  The introversion
    group may be regarded as containing the
    various  introversion-extroversion scales, and
    scales of impulsiveness, receptivity, and the
    strength of the nervous system, all  of which
    have  been interrelated.  The anxiety group
    of measures may be  regarded as comprising
    the various scales  of anxiety, neuroticism,
    ego-strength,  and failure-avoidance motivation,
    all of which are again  interrelated, but
    show  very  little relationship to the
     introversion group  of scales.

    There is some  evidence to  suggest that the 2
    groups  influence different aspects of auditory
    perception, perhaps  respectively related to
    different parts of  the auditory pathway,
    although some  interaction  of scales within
    the 2 groups and certain complex auditory
    measures has been shown to occur.  The
     introversion group  of scales has been found
    to  influence largely the overall level of
    arousal, the variability and perhaps the
    sensitivity of the  detection mechanism,
    and fundamental responses  to noise.   The
    anxiety group  of measures, on the other hand
    appears to be  related rather to the subjective
    response to noise and also the the various
    autonomic responses evoked by these stimuli.

    The relevance  of these personality measures
    to psychoacousticaI testing may be regarded
    as threefold.  First, in the context of
    endeavoring to assess aspects of community
    response to various noise  nuisances, it  is
     important to ensure that the sample of
    subjects selected  is representative of the
    entire population to be exposed to the noise
    and does not comprise just the most sensitive
    or the  least sensitive group of the population.
    Second,  in a diagnostic context in which it is
    essential to have reliable measures, it  is
    useful to have some indication as to the
    degree of reliability which can be attributed
    to the results given by certain individuals
    and to distinguish  the  individuals who might
    require more sophisticated test procedures  in
    order to produce reliable  results.  The third

    and final area of  relevance  is  in more valid
     determination  of the effects of various
     stimuli  which, may  produce a decrement  in
     performance among the  introverts and an
     increment among the extroverts, so resulting
     in  no apparent change when the mean  results
     for the  whole  population  are considered.
03-007

Rice, C.  G.

Southampton  Univ.  /England/

Inst. of  Sound And Vibration Research,
S.U., Southampton  S09 5NH

SONIC BOOM EXPOSURE AND EFFECTS 11.2:  SLEEP
EFFECTS

Journal of Sound and Vibration Research

Vol 20 No 4:511-517, 1972
Laboratory studies and social  surveys have
provided pertinent information concerning the
general problem of sonic boom induced sleep
interference.  Social  survey data indicate
clearly that sleep interference is an important
human response element in community reaction
following exposure to sonic booms.

Two variables associated with patterns of human
sleep which may determine whether or not
awakening to a stimulus will occur are
accumulated sleep time and sleep stages.
Awakening in response to a stimulus appears
more likely to occur with accumulated sleep
time.  Awakening thresholds appear to be  lower
in Stages REM and 2, than in Stages 3 and 4,
both for ordinary noise and sonic booms.

A major factor contributing towards differences
in awakening thresholds from ordinary noise
or boom exposure  is age, older people being
more easily awakened.   The quality of sleep
appears to depend upon temperament, health
and responsiveness to sound during sleep.
Evidence suggests that women are more easily
awakened than men.

Stimuli with  little or no information content
for the sleeper are less  likely to induce a
response than a stimulus having some
significance: e.g., his name.  With repeated
exposures habituation to sounds occur,
particularly when sounds are regular, frequent
and not temporari ly associated with any
subsequent noxious event.   Experimental  data
suggest that adaptation to  the  laboratory
environment  is still present after several
consecutive  nights of exposure to sonic  booms.

In the  range 25-300 N/m2  (as measured outdoors)
children are  relatively  insensitive to  simulated
sonic  booms  while middle-aged people awaken to
about  30? of the  stimuli.   Young  men are
awakened by  10-30? of stimuli depending  upon
the experimental  conditions and techniques.
                                                                There is insufficient evidence available to
                                                                judge the effect which existing environmental
                                                                noises have on sleep patterns and health in
                                                                the population.  A  limited study was performed
                                                                in Sweden where a community was exposed to 7
                                                                sonic booms on irregular days during a three
                                                                month period.  The  reaction was evaluated by
                                                         76

-------
                                                                                                         03-008
                                    PSYCHOLOGICAL & SOCIOLOGICAL
 using  a  postal questionnaire on 220 persons.
 More than  20% of this  random sample of the
 population  had heard all the booms and about
 40?  indicated difficulties  in  returning to
 normal sleep.

 Standardization of  experimental techniques
 among  laboratories  is  necessary.  Simulators
 for  sonic  boom sleep research  should  ideally
 take account of both the acoustic and the
 vibratory  responses of typical bedrooms.  The
 acoustic response  characteristics of  the  indoor
 boom produced by the simulator should be
 specified  and measured.  It  is recommended
 that certain EEG measures of sleep stage be
 obtained.   Response frequencies to stimuli
 occuring in these  stages should be described,
 and  if possible, the time for  returning to
 sleep  following an  awakening by noise.   It
 is  proposed that at least one  standard noise
 be  used  during each experiment.  Presentation
 of  this  standard stimuli could be made to
 correspond to estimated flight schedules.
 Personal  information must be obtained for
 each subject.  Sleep questionnaires and
 subjective tests to assess  fatigue, stress,
 etc.,  are  felt to  be very good indicators of
 sleep  disturbance.

 Existing information  indicates that the
 behavioral  and attitudinal  reaction of a
 community  to noise may be predicted with
 reasonable accuracy only by  combining the
 annoyance  due to the noise  in  question with
 the  total  human  reactions to other noises
 in  the environment.
 03-008

 Aizawa,  R.
 Yoshikai,  K.

 Nagasaki  Univ.  /Japan/

 Dept.  of  Public Health, Nagasaki  Univ. School
 of  Medicine

 ON  THE  INFLUENCE OF CITY NOISE AT MIDNIGHT ON
 SLEEP

 Shinya Toshi  Soon No Suimin Ni Oyobosu Elkyoo

 Nippon Kooshu Eisei Zasshi

 Vol  17, No 8:423-426; No 9:445-448
Traffic noise from midnight to 3:00 am
in Nagasaki City was measured with equipment
conforming to JIS 28731 equipment.  The
number of outdoor measuring points was 247
in residential areas, 48 in commercial areas,
8 in semi-industrial  areas, 8 in  industrial
areas, and 40 in heavy traffic regions; or a
total of 351  measurement locations.  Duration
of measurements was two months.
The community's annoyance reactions (relating
TO sleep disturbance) were investigated at the
same time by self-checking questionnaires
for 3,493 residents  in fhe vicinity of the 351
places,  Mean values of noise  levels were
calculated for each  point after the 10*
lowest readings were thrown out.  The  lowest
values of these means were 59 dBA for the
industrial area, 65  dBA for semi-industria1
and commercial areas, and 50 dBA for residential
areas.

Of the residents (1,110) investigated  in the
city, 32% complained of annoyance, relating
to sleep disturbance from street noise.  Their
complaints included  lengthened tine for falling
asleep, waking up in the middle of the night,
reduced waking time  in the morning, and
drowsiness during daytime bacause of lack of
sleep the night before.  Of these 1,110
residents, 686 residents in the residential
area (28% of residents in that area),  29f>
(40%) in the commercial area, and 62 (50?)
in the semi - i ndustri a I  area were disturbed
in their sleep by the street noise at  midnight.

The degree of the annoyance reactions  was a
function of  volume ut- traffic on nearby roads.
The size of  roods in Japan in decrea-ing order
is: national,  prefectural,  municirai,  and
pri vate.

Fifty percent (101  residents) of the residents
in the vicinity of  the national road in the
city were annoyed by noise.   So were 42? (90)
in the vicinity of  a prefecfural read,  32?
(787) in the v'cinity of city streets,  and
21? (132) in the vicinity of a private road.

Thirty percent of the residents in the city
suffered sleep disturbance when the median
level of the traffic noise was 40-49 dBA.
At a median  level  of 55-59 dBA, abou+  50%
of the residenfs complained of sleep
di sturbance.
03-009

Lukas, J.  S.

Stanford Research Inst., Menlo Park, CA

AWAKENING EFFECTS OF SIMULATED SONIC BOOM!
AND AIRCRAFf NOISE ON MEN AND WOMEN

Journal of Sound and Vibration

Vol 20 No 4:457-466, 1972
The effect of sonic booms in the light of
potential  SST development on a sleeping
populace is discussed.
                                                    77

-------
03-010
                                        PSYCHOLOGICAL & SOCIOLOGICAL
     In the course of several studies, 22 male
    and female subjects, ranging In age from
    5-75 years, were subjected while asleep
    to simulated sonic booms equivalent to
    84 dBA, and to recordings of subson'C
    t3t flyover noise equivalent 86 dBA near
    rne subject's ear.

    'esults of these studies show general
    patterns according to age and sex.
    Children exhibit the least awakening,
    while older people tend to be awakened
    most easily.  Individuals vary greatly
    within common age groups, with middle
    aged men with high sensitivity awakening
    ? out 20% more frequently than old  men
    with low sensitivity.  Subjects were most
    prone to awakening during sleep stages
    2 and REM.  Women were found to be  more
    sensitive to noise than men, in addition
    Jo being awakened much more early by
    aircraft flyover noise than by simulated
    sonic booms.
     03-010

     Myasni kov,  V.  i.
     Kozerenko,  0.  P.
     Yakovleva,  I.  Ya.

     Air  Force Systems Command, Wright-Patterson
     AFB, OH

     F >reign Technology O'v.

     PECULIARITIES  OF HUMAN SLEEP UNDER CONDITIONS
     OF CONTINUOUS  PROLONGED  INFLUENCE OF
     BROAD-BAND  NOISE OF AVERAGE  INTENSITY

     Springfield, VA, NTIS, AD 696500, 1969,
     17p.  HC: $3.00, MF: 95 cents
     Studies were  conducted at the Garbov Laboratory
     (USSR) on  the effects of broad-band noise (2000-
     12,000 Hz) of 75-78  dE intensity on sleep and
     the  transitional state between sleep and
     wakefulness.  Ten healthy subjects aged 23-36
     years old  were exposed to the noise continuously
     up to the  onset of sleep (10-12 Hrs.) and then
     throughout the sleep.  The reason for the study
     was  that Soviet cosmonauts,  including Nikolayev
     and  Tereshkova, complained that the noise of
     the  spaceship cabin  ventilating system (76 dB,
     frequency  spectrum 800-2000  Hz) interfered with
     their rest, although other cosmonauts were
     not  disturbed.  Likewise, noise in Gemini-5
     periodically  interfered with the sleep of
     American astronauts  Cooper and Conrad.

     Reaction of the subjects to  the noise varied
     during the pre-sleep period.  The broad-band
     noise  led  to  the development of drowsiness
     in certain suojects  and fatigue (expressed as
     tension,  irritableness, and  absence of desire
to work)  in others.  Latent period of motor
reaction  increased, as did thresholds of
auditory sensitivity.

Six of the ten subjects fell  asleep quickly
(7-25 min).  Three subjects took longer than
72 min, but in only one case was this clearly
attributable to the noise exposure.  Quality
of subsequent sleep was related to how
quickly a subject fell  asleep.   Most of those
who fell asleep rapidly had strong and deep
sleep.  Those wno did not, had superficial
sleep with frequent wakenings.

A direct relationship was observed between
restoration of auditory thresholds and the
quality of the sleep period.   For subjects
with good sleep,  a lowering of  the auditory
threshold averaging 15-35 dB was observed in
comparison to threshold before  sleep,  testifying
to the restora+ion of the auditory  analyzer
during sleep.   Subjects who had, in their
opinion, poor sieep were observed to have
increases in auditory threshold of  15-30 dB.

Conclusions are:   (1) the stay of man in a noisy
setting can disturb the quality of sleep;
(2) unequal auditory adaptation to different
frequencies can make broad-band noise seem more
unpleasant to cosmonauts  in flight;
(3) the degree of  restoration of disturbed
functions of the  auditory analyzer  is directly
dependent on quality of sleep;
(4) capacity to withstand continuous noise well
should  be a criterion  for selection of cosmonauts;
they  should be able  to  sleep well,  and also the
auditory  analyzer should  have good  adaptation
as  well  as  sensitivity  to tones  and speech
si gnaIs.
03-011

Dobbs, M. E.

Stanford Research  Inst.,
Menlo Park, CA

Zip  94025

On:  BEHAVIORAL  RESPONSES TO AUDITORY
STIMULATION DURING SLEEP

Journal of  Sound and  Vibration

Vol  20 No 4:467-476,  1972
 Although  much  research  has  been  concerned  with
 numerous  aspects  of  sleep  in  man,  little
 experimentation  has  been carried out to
 evaluate  the long-term  physiological  and
 behavioral  effects of sleep disruption  that
 might occur in response to  auditory stimuli.
                                                         78

-------
                                   PSYCHOLOGICAL & SOCIOLOGICAL
                                                                                                         03-012
It is generally agreed that sleep  consists  of
five relatively well-defined stages during
which people respond differently to varying
levels of auditory stimulation.   During a
normal night of sleep the cycle  of five stages
repeats approximately every 90 to 120 min,  with
decreasing amounts of stages 3 and 4 and
increasing amounts of rapid eye  movement (REM)
time as the night progresses.

The auditory awakening threshold (AAT) is
defined as a measure of how much sound
stimulation is required to awaken  the sleeping
human subject.  Several variables  are
associated with the AAT.   Among  these are
stimulus intensity, sleep stage, subject
differences, accumulated  sleep time (and/or
time of night), amount of prior  sleep
deprivation, and the amount of past
experience with the test  stimuli .

It appears that the awakening thresholds in
stage REM and stage 2 are similar if the
auditory stimuli are ''meaningful' .  A person in
some stages of sleep can  discriminate among
auditory stimuli in terms of their personal
significance and can "listen" for certain sounds
while asleep and at the same time ignore others.
There may be some habituation to successive
stimuli.  Studies have shown adaptation of  a
behavioral awakening response when simulated
sonic booms and jet aircraft noise were
presented over several test nights.

Both the physiological and the psychological
consequences of sleep-disturbing auditory
stimuli are greater for old and  middle aged
persons than for those of college  age.  The
cyclic patterns, which are clearly defined  in
younger subjects, become  interrupted in the
older subjects, with less of stages 3 and 4
and increasing amounts of stages 1 and 2.   A
longer period for adaptation to  laboratory
conditions is required for the aged than for
young adults.   With increasing age, REM time
is reduced.

In this experiment it was found  that the sleep
of children is essentially unaffected by either
simulated sonic booms or  subsonic  jet flyover
noises over intensities from 0.63 to 5.0lb/sq
ft (30.18-129.50 N/sq m)  for booms and 101
to 119 PNdB for flyover noises.   Partial  sleep
deprivation experiments have shown that short-
and long-term sleepers have equal  percentages
of REM sleep.   It appears that REM sleep
duration adjusts to length of sleep.

Older age groups show greater performance
decrement with increased  sleep disruption than
do younger age groups.
03-012

Scott, W. N.

Chrysler Corp. , Highland Park, IL

12800 Oakland Ave.

VEHICULAR NOISE

At: American Association for the Advancement
of Science, 138th Meeting,  Philadelphia,
DEC 29,  1971

Highland Park, IL, Chrysler, 1971, 5p.
The Automobile Manufacturer's Association
sponsored a research project concerning the
annoyance due to motor vehicles.   The heart
of the research project was a social  survey
in Boston, Detroit and Los Angeles and
physical  measurements of community noise.
The interviewees who cited annoyance  with
vehicle noise were usually at home; they
were annoyed predominantly in the evening or
during the night, and 22% of the respondents
were annoyed because of sleep interference.
People were mostly annoyed by automobiles,
then motorcycles, diesel trucks and buses.

Another part of the research project  related
to the subjective responses with  measured noise
levels in the areas where the respondents
lived.  Only a third of the variance  in
annoyance could be accounted for by the
loudness  level.  Factors other than the
amplitude of the noise were important.   It
was also shown that the peak noise levels
correlated well with the respondents  judgements
of noisiness.   Squealing tires, drag  racing,
bad mufflers or other operator control led
action were considered the most annoying noise
sources.

It would  be most efficient to reduce  the peak
noise levels of diesel  trucks since their
annoyance index is much larger than that of
any other vehicle.  Roadway design, land
use, and  traffic control may be necessary to
reduce passenger car noise.  By applying
today's technology to a future truck,  1980
or later, it would be possible to reduce the
component noise levels by about 6 dB.   Tire
noise will  not likely decrease significantly
in the near future.   Overall  noise levels at
35 and 55 MPH  can be expected to  be reduced
to about  84 and 89 dBA respectively.   At
road load,  tire and aerodynamic noises  are
typically equal to or greater than powerplant
generated noises.   Passenger car  tires  already
have all  the presently known tire noise
reduction techniques applied to them.
                                                    79

-------
03-013
                                       PSYCHOLOGICAL & SOCIOLOGICAL
     03-013

     Becker, R. W.
     Poza, F.
     Kryter, K. D.

     Stanford Research  Inst., Menlo Park, CA

     On:  A STUDY OF SENSITIVITY TO NOISE

     Springfield, VA, NTIS, AD 728332, 1971, 63 p.
     HC:$3.00 MF:95 cents
    The effects of certain kinds of  impulse noises
    and typical nonimpulse noises upon the
    physiological and psychological  behavior of
    adults were  investigated.  Specific goals were:
    1) to compare the effects of the two kinds of
    noises, 2) to compare psychological with
    physiological responses, and 3)  to attempt to
    find other characteristics of those individuals
    who were  found to have the greatest reaction to
    noi se.

    Sixteen everyday noises were reproduced in the
    laboratory and presented to 140  subjects over a
    6 month period.  Typical noises  included
    airplanes, sonic booms, vacuum cleaners,
    barking dogs, motorcycles, truck traffic, and
    freeway traffic.  Heart rates and
    eIectromyographic measurements were made.
    Subjects  rated the various noises subjectively
    and filled out general questionnaires on
    attitudes toward noise.

    The relative ranking of the perceived annoyance
    of the various noises remained constant over
    the six month duration of the experiment.  The
    2.5 psf boom was distinctly the  most annoying
    sound.  The  1.25 psf boom was rated more
    annoying  than all other noises except for the
    90 dBA jet flyover and the 81 dBA vacuum
    cleaner.  The 0.63 psf boom was  rated less
    annoying  than all other noises except for the
    67 dBA truck traffic and the 62  dBA motorcycle
    recording.  The sonic boom overpressures are
    expressed at the  levels that would be found
    outside a typical frame house with windows and
    doors closed; the subject actually heard the
    booms and noises at the  level that would be
    present  inside the house.


    The  index of psychological sensitivity to
    noise revealed potential differences between
    the most  sensitive third of the  subject
    population and the  least sensitive third of the
    population.  The noise-sensitive  individuals
    rated all kinds of noises as being more
     intrusive in their daily activities then the
    noise-insensitive individuals.   They were also
    more  likely to perceive themselves as being
    more sensitive to noise than the average
    person, and they were more likely to believe
    that noise was affecting their personal health.
    The noise-sensitive individuals  were also more
    negative  in their ratings of non-noise factors
    in their  environment and were more likely to
    have high anxiety scores than were the noise-
    insensitive  individuals.  The best prediction
of noise sensitivity came from questions about
individual's beliefs concerning the effects of
noise upon their health and behavior intended
to ameliorate the effects of noise.

Analysis of the physiological  reaction to the
noise indicated a definite heart acceleration
in response to the simulated sonic booms.  This
was true even of the 0.63 psf boom, which was
not rated as very annoying.  It was not
possible to find an index of individual
physiological sensitivity, nor was there
evidence of correlations between psychological
and physiological reactions to noise.  The
results cannot be taken as proof that such
responses and correlations did not exist;
rather the discovery of good indexes of
physiological responses to non-impulsive
noises may depend upon the monitoring of more
physiological parameters and the use of more
elaborate electrophysiological  recording and
signal detection techniques.
03-014

Neki pelov M. I.

Irkutskiy Meditsinskiy Institut /USSR/

TRAFFIC NOISE INTENSITY IN IRKUTSK AND ITS
HYGIENIC ASSESSMENT

Intensivnost Transporfnogo Shuma v Irkutske i
yego Gigiyenskaya Otsenka

Gigiyena i  Sanitariya

No 8:29-33, 1971
In many large cities and growing communities,
noise has become a major problem. Such a problem
developed in Irkutsk, a rapidly developing
industrial city in the Soviet Union.  This
study was undertaken to measure the noise
levels of various kinds of traffic, to evaluate
public opinion of noise, and to recommend
measures for noise reduction.

Special research was carried out to determine
the characteristics of noise produced by
various kinds of vehicles.  Road, air, and
railroad traffic were all  taken into account.
The highest urban noise levels were created by
airplanes (81-105 dBA), helicopters (73-94 dBA),
and trucks (72-103 dBA).  Automobiles were
found to produce the least noise (66-75 dBA).

During the study, peripheral factors affecting
noise  levels were found.  The quality of
automobile engines, conditions and velocity of
traffic, street width, building height, building
location and time of day, were considered as
factors.  The highest noise  levels  (85-95 dBA)
were measured on unpaved and cobblestone roads.
                                                         80

-------
                                                                                                         03-015
                                   PSYCHOLOGICAL &  SOCIOLOGICAL
In comparison with asphalt roads,  These were
4 and 9-11  dBA louder, respectively.   Faulty
engine parts emit+ed 3-5 dBA rnor,  rhan
well-tuned  engines.  The intensi!~y of noise on
narrow streets rated 2-5 dB higher than on wide
roads.  The  least trafiic noise was 30-32
dBA, measured in urban apartments  with
windows closed between 1 and 4 am, and fhe
most 63-70  dBA,  between 8 am and 8 pm.

In  Irkutsk, noise caused by air traffic affects
84.3? of its area;  20.5? of the area is subject
to noise levels of 90-100 dBA and  higher.

For a subjective evaluation, questionnaires were
sent out to 700 persons living within a 10 km
radius of the airport.  A large majority (65?)
complained  chiefly about the noise from air
traffic, which dislurbed them day  and night.
Noise from  other traffic sources was reported
to be less  disturbing.  Those who  complained
of airport-related noise rated it  tw i c'j as
high as these complaining chic*i/  of fiafric
noi se.

An  interesting outcome of this study was that
attitudes towards traffic noise were in
direct proportion TO Tne age of the population.
The mos f indifferent age qrojp v,as uncltr 20
years of age, wifh 15-28? registering
complaints.  The age group of 21-40 years of
age had a stronger feeling  howards noise (56-
67?), and those older Than 61 had  The strongesf
reaction (65-77?).

If uas also found that noise tolerance to air
tratiic was related \> trc  length  of time the
population  lived near the airport.  Of those
living near fhe airport for  less 1hsn 3
years,. 76-35* found the r, ,\  ,e d'sturtinj,
inhabitants from 3-6 years,  65-72?, I rom 6-12
years, 54-53?, and longer Than 12  years,
41-50?.  These rosulK i-jioate that tolerance
of noise does develop in rslation  to the
exposure to it.

In this study, sor:« r-  »ni:,endat ions on traffic
noise control were mace oonsisting mostly of
architectural planninn and admi"'strationaI
organization neasures.  Jirect ..olulion
included the paving c r roads, sf icier controls
on the loudness  of automotive engines, and
the isolation of heavy .jrban traffic from
domestic areas.
03-015

Borsky, P. N.

Co Iumb i a Univ.

School of Public Health and Administrative
Me d i c i n e

On:   EFFECTS OF NOISE ON THE COMMUNITY

At;   American Association for the Advancement
of Science, 138th Meeting, Philadelphia, PA,
DEC 29, 1971

New York, Columbia Univ., 1971, 14 p.
Noise intensity near airports and major
highways may be approaching the health hazard
exposure levels and may be Cu'.Tr; uting +o
hearing loss.  Intense no'se ^s an
environment! stressor has been found to
increase a number of physiological responses,
such as cardio-vascul ar, gasfro-intestinal,
and endocrine arid central  nervous system
responses.  Whether these pbys,0'ogicnl
reactions p I di. e soi.e slraln 01 the >   in < srr
and if continued over suf f i 01 er.i  ly long periods
are precursors or causes of disease has not
been established.  It  is believed that the
major acute effects of intense environnental
noise are primarily psychological annoyance
responses.  1 r: terference with sfeer- and
communications as .-.o I I  as  nnv.a' rec '-,'• " i.^  ,rj|
vibrations are the most frequently reported
disturbances.  Variations  in noise exposures
generally account tor 20-25? of the variance
in hurrtcin annoyance.   Attitudes, experiences
and other human variables  account for  as
much as two-fhiids of  tiie response differences.
Combined British and American recenf surveys
of residents living near airports indicar
that about half of all  persons with moderate
psychological pivJispositions or  atliTudes of
fear and aircraft operator misfeasance report
serious annoyance at Composite Noise Rating
(CNR)  levels of 100 or greater.  At Ihe same
noise exposures, over 70?  of those persons
with feelings of high fear and high misfeasance
report high annoyance,  compared to only 12? of
similarly exposed peopie wiih no fear and
feel i'ia_ of no misfeasance.
                                                    81

-------
03-016
                                       PSYCHOLOGICAL & SOCIOLOGICAL
    03-016

    Nakamura, 6.

    Kyoto City Host! pa I  /Japan/

    13-40 Kihata  Minamiyama  Uji  City,  Kyoto

    HOSPITAL ENVIRONMENT

    Byooim Kankyoo

    In:  Kocgdi. Yosoku to Taisaku

    Tokyo, Vjahi  Shimbunsha,  1971,
    ?9!f..  (p. 164-174)
    Three doctors at the Kyoto City  Hospital  made
    a sti've/ of 956 families  and  293 clinics
    'providing both out-patient and  short hospital
    s+ay services) ana physicians' offices to find
    out the effect of noise on their envircnnent.
    The questionnaire covered the following areas:

    (1) influence of noise from daily activities
    on conversation, lelephone calls, reading and
    concentration while at work;  influence on
    chi Idren's study;

    (2) emotional irritation; influence on
    recuperation at home;

    (3) sluep disturbance  in  the  middle of the
    night 21 id eariy norning;

    (4) disturbance of naps;

    (5) physical effects:  appetite,  fat'gue,
    headache, palpitation  and ringing in the  ears;

    (6) influence on ability  to listen to a
    stethoscope.

    Degree of Nuisance (DN) was calculated in
    terms of percentage by dividing  the number
    of people answering ''yes" to  the question
    "is noise a nuisance?" by the total  number
    of respondents.  The results  of  the survey
    from residents reveals that DN/emotional
    irritation was more "than  50*  when the noise
    level war, more than 50 dBA.  This DN was  15-25?
    higher than DNs tor other Types  of effect.
    When noise  level was more than 60 dBA,
    DN/emotional  irritation was 69?.  Adverse
    effects on naps, daily activities, and sleep
    were rankec second, third, and fourth
    respectively,  in DN in this survey.

    The survey of clinics  and doctors'  offices
    shows that DN is much  higher  for the same
    noise  level than it is in a residential
    setting.  When the noise  level  is 36-40 dBA,
    DN/emotional  Irritation  is 36-40?.  When
    the  level  is  50 dBA, the various DNs are
    much higher-  67?  in doctor's conversation
    with patients, doctor's  rounds,  and
    audiometry;  80?  in  listening to 1 he
    stethoscope;  and 90?  in  listening to a
    fetus  by stethoscope.  When a doctor  listens
to the stethoscope during chest diagnosis and
treatment, DN is 65$ for a noise level  of
30-40 dBA.

The frequency of lung and bronchial sounds
is below 1000 Hz and in the 2000-3000 Hz
range for coughing.   A stethoscope on the
market today has a transmission loss of
30-40 dB in the 2000-4000 Hz range.

Vibration of the rubber tube itself and
permeability of noise through the rubber
tube from outside noise make the stethoscope
more difficult to use, particularly for city
doctors.  When the background noise level
increased from 30 dBA to 35 dBA, patients
required 20? more time to fall  asleep and
woke up earlier in the morning 10$ of the
time.  The survey found that a mean noise
level of 50 dBA within the hospital caused
emotional tension, sleeplessness and shouting
when conversing.  The main sources of noise
within the hospital  were loud speakers, radios,
cooking in the kitchen, trucks, ambulances,
footsteps, elevators, motors, noise from
experimental animals, and cleaning by
Jan itors.

The survey also found that when noise  level
exceeded 60 dBA, 60-69? of patients either
(1) complained by telling doctors that they
wanted to recuperate at some other place,
(2) got angry or, (3) became nervous.  Also,
50$ of patients complained that they could not
sleep, and had to shout to carry on a
conversation.  Doctors and staff also
complained about difficulty in using
stethescopes.

When the noise  level was 55 dBA during morning
and evening hours more than 50? of both staff
and patients were annoyed.  The level
prescribed by the environmental standard is
40 dBA.

The survey found that noise did not result in
doctors making many more mistakes  in diagnosis.
However, the frequency of mistakes by the staff
increased in simple tasks such as matching blood
for transfusions, measuring correct quantities
of the right medicines, and recognition of
patients.
03-017

Angevine, 0. L.

Anderson and Angevine,  Inc., E. Aurora, NY

PSYCHOLOGICAL  FACTORS  IN ACCEPTANCE OF NOISE

New York, Anderson and Angevine, 10p.
                                                         82

-------
                                                                                                         03-018
                                   PSYCHOLOGICAL &  SOCIOLOGICAL
Emotional or subjective reactions to noise
vary from one individual to another.  Several
psychological factors are involved which will
determine a person's attitude toward noise:

1)  Noises produced by other people are more
disturbing than noises produced by oneself.
2)  A certain noise must be perceptible against
background noise to become irritating.  Music
and speech are more difficult to disregard than
random sounds.

3)  People who suffer from anxiety are much
more likely to be disturbed by noise than those
who do not.

4)  Individual conditioning and perception of
reality determines how a person will react to
noises.   Individuals who were exposed to air
raids during WWII will react much differently
to sirens than will those of today's generation.

5)  Adaptation to a noise develops  if it
maintains a steady value; only if there are
changes  in the noise  itself will  it then be
noticed.  Also, noise is more apt to be adapted
to if  it occurs  in the presence of background
noise.

6)  Individual interpretation and recognition
of sounds determine whether they are annoying
or not.   For example, a man experiencing the
noise of  an earthquake for the first time
thought his furnace had exploded.

7)  A study has shown that people will accept
more noise from aircraft than from cars simply
because they accept aircraft to make more noise.

8)  Reaction to noise also depends upon its
appropriateness.  Consider the difference
between hearing a brass band while  in church,
and hearing  it while watching a parade.

9)  Some  noises are not annoying until they
are combined with mental pictures.  The sound
of fingernail running down a blackboard does
not bother some  people  until it  is  identified.
Then,  it  is  intolerable.

10)  Cultural differences influence the loudness
of conversation.   Americans  are generally
considered very loud talkers  by Europeans.

11)  Once a person complains  about noise,  he
is thereafter much more sensitive to it.

12)  Fatigue from noise comes from trying  to
talk above it or not being able to talk
above  it.   Thfs  fatigue can  lead  to stress.

13)  Biological  rhythms,  common to  both  men
and women, determine response to  noise.   At
the time when a  person is  most  awake,  noise
wi I I  have the greatest effect.
03-018

Hockey, G. R.

Durham University /England/

Dept. of Psychology

EFFECTS OF NOISE ON HUMAN EFFICIENCY AND
SOME  INDIVIDUAL DIFFERENCES

Journal of Sound and Vibration

Vol 20 No 3:299-304, 1972
Laboratory research into the effects of loud
noise on the efficiency with which human beings
carry out mental work has a long history in
experimental  psychology.  Much recenr research
has tended to concentrate on continucjs noise,
as found in most industrial and n I'tery
situations, and particulary unchcijirg broad-
band noise.  Performance changes t rought about
by exposure to continuous noise aduaily
increase with time spent at the tas    One
such task is that of vigilance or monitoring.

Normally, efficiency at monitoring drops
off with time spent on the task.  Noise,
in these studies, accentuated this effect,
increasing the number of signals missed, but
only at the end of the work period.  Although
noise does not affect the overalI speed at
which successive decisions are made, it
does increase the number of wrong decisions
(or result in occasional very long decision
times).

It is important to point out, however, that
noise can sometimes enhance efficiency of
work.  A number of studies have demonstrated
better performance at the end of a vigilance
task when the level of background noise was
continuously varying, though this is the
kind of environment which is usually associated
with distraction.  Certain kinds of variable
noise (that of a car radio, for example)
clearly prevent boredom and may thus have a
real  effect on efficiency.

Noise can be assumed to have a general  effect
of increasing the amount of stimulation reaching
the central  nervous system (CNS).  On the basis
of results from clinical observations and
research on anxiety and the psychological  stress
it has been suggested that a high level  of
arousal  may result in efficient behavior.   A
principle of  this kind has been  found to apply
to the effects of noise in monitoring tasks.
Primary task  performance (tracking)  is
faci 'itated,  especially towards  the end of 40
minute work period, while monitoring is, on >"he
whole,  impaired.  Signals occuring  near the
periphery of  vision (80 degrees  each side) are
more  likely to be adversely affected by noise
than  those in the center,  which  may  show an
improvement.   In other works,  noise is
producing a structured change  in the way in
which attention  is  distributed over the
                                                    83

-------
03-019
                                       PSYCHOLOGICAL & SOCIOLOGICAL
    components of the task, causing it to become
    more selective.  This has the effect of
    enhancing performance on high priority aspects
    of the task at the cost of neglecting low
    priority elements.

    Little is known of the relation between
    personality and susceptibility to loud noise,
    at least as far as changes in efficiency are
    concerned.  The Heron unsociabi I ity scale,
    a measure of introversion-extroversion,  has
    proved to be of considerable value in accounting
    for individual  differences in mental  work
    efficiency in general.

    Both tracking and selectivity give consistently
    positive correlations with introversion.  The
    degree to which the distribution  of attention
    changes with noise, however,  is consistently
    negatively correlated with introversion.

    It has been demonstrated that  liking  for noise
    exhibited by extroverts extends to preferred
    levels of continuous white noise  in the same
    kind of task.  It is not at all clear at the
    present time how these differences between
    individuals in  the effects of noise can  be
    interpreted.   The underlying  basis fcr such
    differences will  probably be  found in further
    neurophysiologicaI work on the structure of
    the various mid-brain arousal systems and
    thei r control.
The highest noise intensities occurred on the
lower floors of the buildings, and in
buildings with panel  construction.  Noise
intensities themselves were found to depend on
the water pressure inside hydrant fixtures:
the higher the water pressure, the higher
the noise levels.

The noise levels had more effect on confined
and sick people than others.  Complaints of
noise ranged from 56-73$ of those polled;
64-89? of the inhabitants of panel
construction buildings complained of noise,
while 52-77% of those living in brick
buildings with iron reinforcements complained
of noise.

A direct relationship was found to exist
between the noise level  and the number of
complaints.   As the noise level increases by
5 dBA, the number of complaints increases by
10%.

It is concluded from this study that the noise
from water fixtures in apartments is a serious
problem, and that more attention should be
paid to quieting it by acoustic insulation.
    03-019

    Neki pelov,  M.  I.

    Irkutsk, USSR

    On:  INTENSITY &  DISTURBING EFFECTS  OF NOISE
    CREATED BY  PLUMBING IN  BUILDINGS

    Intensivnost,  i  Bespokoyashcheye  Deystviye
    Shuma, Sozdavayemogo Vodoprovodno-
    Kanalizatsionnym Oborudovaniyem v Zdaniyakh

    Vodosnabzheniye i  Sanitarnaya Tekhnika

    No 1:13-15, 1972
    Establishment of controls  on  construction
    organizations for reducing noise is reported
    in the light of an investigation of plumbing
    noise in buildings conducted  by the
    Department of Hygiene of the  Irkutsk Medical
    Institute.

    The test assessed the noise intensify  11 UH,
    v.rier ;   .,  .jrJ systems in domestic quarter-1
    in various regions of Irkutsk.   MuIti-bfuriod,
    we I I-constructed buildings, new ano  Id,  W'.re
    evaluated.  Subjective public reaction to  the
    noise was obtained from questionnaires
    delivered to the inhabitants  of 657 apartments.
    A total  of 2,015 noises was measured during the
    course of the study.
03-020

Stanios, W.
Semczuk, B.
Domanska, K

Akademia Medyczna, Lublin /Poland/

Lubli n, Poland

HEARING DAMAGE AND RESULTS OF CLINICAL AND
PSYCHOLOGICAL RESEARCH ON PERSONS WORKING IN
NOISE

Uszkodzenie Sluchhu Oraz Wyniki  Badan
Klinicznych i  Psychologicznych Osob
Pracujacych w Halasie

Pamietnik XXVII  Zjazdu Otolaryngologow
Polskich W Katowicach 1968 r.

Warsaw, Panstwowy Zaklad Wydawnictw
Lekarskich, 1970, p.  15-17
A study was undertaken in Poland to determine
the aural  and extra-aural effects that result
from occupational  noise.   The group examined
consisted of 500 persons, 20 of which were
women.  The examination was subdivided into
otolaryngologicaI  and internal.  Hearing was
tested by means of whispering.  Blood pressure
was taken before and after work and an eye
test was given.  Reaction tests were also
given to determine concentration span and the
quickness of perception.
                                                        84

-------
                                                                                                          03-021
                                    PSYCHOLOGICAL & SOCIOLOGICAL
 Analysis of group  I of the  KFWM Plant  working
 between 2 and  4 years  in  noise  levels  of
 100 dB showed  18.3? of hearing  loss, and
 decreased hearing  sensitivity by an amount
 of 25-35 dB.   In workers  of 5 to 10 years the
 percentages rose to  19.2  and  loss of
 24-35 dB, and  for  those employed for 11 or
 more years the percentage  increased to 25.4?
 and  loss of 29-44  dB.

 In a noise environment of  100 to 122 dB,
 the statistics showed a 2-3?  increase  in each
 category.  Also the blood pressure  increase was
 from 3-5 mm Hg.

 For the psychological test, 2 groups were used:
 the first group consisted of  75 persons who
 worked  in noise surroundings  up to  100 dB and
 the second group  involved 25  persons employed  in
 noise  levels  above 100 dB.  Tests were
 conducted before and after  work.  The  reaction
 time of the hearing  stimulus  before work  in
 group  I was 280 msec and  303  msec after work.
 In respect to visual stimulus, the  reaction
 time was 274  msec  before  work and 289  after
 work.

 It was found  that  after 3 hours' work  in noise
 levels 90 dB  and above, the concentration span
 and quickness  of perception showed  considerable
 drop.

 The study showed that a degree of hearing  loss
 occurs  in noise  levels of  85-100 dB, and that  a
 temporary threshold  shift of  up to  13-18
 dB occurs after work, but is  rectified to a
 certain degree after a few  hours rest.  In the
 light of hemodynamic changes  and psychological
 reaction, noise  is definitely a negative factor.
 03-021
In five workshops the following factors were
studied:  type of work, source of noise,
intensity of noise, spectrographtc character
of noise, mode of exposure to noise, and the
situation and response of the worker to noise.

A questionnaire surveyed 920 workers and 8
general kinds of complaints were determined:
1) fatigue, 2) headache, 3) palpitation,
4) stiff shoulder, 5) decrease in body weight,
6) disturbance of sleep, 7) irritation, and
8) gastrointestinal disturbance.

Also surveyed were 92 workers exposed to noise
in an adjacent workshop over a 3 month period.
They were investigated before and after the
administration of a placebo.

Workshop D had the highest complaint rate, as
compared with workshop E, which had the lowest.
There was no direct relationship between all
types of complaints and actual noise level,
except in the case of workshop E.  Noise
levels in workshop A were the highest, although
workshop D registered the most complaints.

These results cannot be interpreted on a
physical  noise level  basis alone.  Another
factor other than noise intensity and hearing
damage must exist.  Workshop D was the only
one which did not produce  its own noise; hence,
it may be more irritating to  listen to noise
from a source other than one's own.
Fig. 1  shows the results of the group
administered a placebo.  In each group there
was not much change in complaints.  The results
of this study  indicate that complaints related
to noise exposure do not necessarily relate
to the intensity of noise.  A psychological
factor must be involved.  Conversely, the
results of the study on the placebo group
indicate that the basis for complaint is not
completely psychological either.  A reasonable
balance must be somewhere in between.
 Matsui,  K.
 Sakamoto,  H.

 Mie  Prefectural Univ., Tsu, / Japan/

 THE  UNDERSTANDING OF COMPLAINTS  IN A NOISY
 WORKSHOP
 Ergonom i cs

 Vol  14 No  1:95-102,  1971
This article reports testing to determine
personal attitudes toward noise.  Although
the Noise Rating Number developed by the
International Standards Organization (ISO)
converts a physical value into a psychological
value,  individual attitudes toward noise vary
greatly, and there may be no complaints even
though noise levels are dangerously high.
The Noise Rating Number is not adequate to
determine personal  attitudes toward noise.
5  6
it
a
I  *
"p*
e
o
U
•8  2
I
            \777\
                     Before Administration
                  After Administration

               /


         Occasionally   entirely   punctually

              Moae of Administration
 FIGURE L  Changes in the Number of Complaints Before and
         After Administration of Placebo
                                                     85

-------
03-022
                                       PSYCHOLOGICAL & SOCIOLOGICAL
    03-022

    Burrows, A. A.
    Zamarin, D. M.

    Douglas Aircraft Co., Inc.

    Zip 90801

    AIRCRAFT NOISE AND THE COMMUNITY: SOME RECENT
    SURVEY FINDINGS

    Aerospace Medicine

    Vol 43 No 1 :27-33, 1972
    To study community reaction to aircraft noise,
    two surveys were conducted  in 1968 and 1969 in
    the communities surrounding Los Angeles
    International Airport.  The survey
    questionnaires sought  information in the
    following areas:

    1. Identification and  definition of aircraft
    noise as a problem-comparison with other major
    probI ems
    2.  Awareness of aircraft noise and its effects
    on daily activities
    3. Emotional reactions to aircraft noise
    4. Noise abatement activity
    5. Prior awareness of  aircraft noise
    6. Perceived economic  effects of aircraft noise
Figure 1 shows the results of a rating of the
seriousness of 4 current problems,  including
aircraft noise.
The frequency of awareness is shown in Figure
2 for the total  sample and by distance to the
ai rport.

Of the sample 31? were aware of aircraft noise
twice a day or more, while 2\% were never aware.
Those respondents living less than 3 miles from
the airport were much more likely to be
continually aware of aircraft noise.  Awareness
of aircraft noise changed with the time of day,
being low from 1:00 am to 1:00 pm.  A gradual
increase occured between 1 and 5 pm with a
rapid increase after 5, with a peak awareness
at 7:00 pm.
Respondents were asked about their emotional
reactions to aircraft noise.  Figure 3 shows
the most common responses.  The majority of
the sample reported no reaction at all.  The
next most frequent responses were "annoyance"
and "acceptance."  It was found that people
most exposed to aircraft noise tended to
polarize in their reactions, becoming either
angered or adapted to it.
                   FIGURE  2.
                         Frequency of awareness
                   of aircraft noise.



—

-
\
^

^

\


n




?B









23







	






ABC



-



10

v










10




A



--



10




s
TOTAL A - O3 Ml CVO^,
K\N SAMPLE 8 = 3S Ml IN-167)
L 	 ' (N-500) C = OVfR 5 Ml IN 1841
, 	 .DISTANCE
j 	 j FROM
iV»
14


8
"I

J_
—


\
\


10




rn






14

































24








	






— i





plL






14
12j





—











n






30








- -

14

10




— i





C ABC ABC ABC ABC
                   FIGURE  1.               £
                         Seriousness ratings for   o so
                   four current problems.          £
                                            30	—
                                                         86

-------
                                                                                                         03-023
                                   PSYCHOLOGICAL & SOCIOLOGICAL
Only 4% of the sample had ever made a complaint
(6% in 1968).  Complaints were generally that
there was too much noise or that aircraft were
flying too low.  Most respondents felt there
was no result from their complaints.

The survey on prior awareness of aircraft noise
showed that 43? of the entire sample knew of
it before moving in, and 60% of those living
within 3 miles of the airport were aware.

The economic effects of aircraft noise were
important to most people.  Respondents were
far more likely to perceive an increase in
their property value over the preceding 5
years than a decrease.

When asked how much they would be willing to
spend to eliminate aircraft noise, 58% of the
sample answered that they would be unwilling
to pay anythi ng.

Of the sample 49% were aware of current noise
abatement activities, while 66% of those
living within 2 miles of the airport knew
about them.  The most frequently mentioned
activity was "developing quieter engines."

The results show that community reaction to
aircraft noise in Los Angeles is not as great
as might be expected.  Annoyance is about even
with apathy, and complaints are almost
neg I i g i b I e.
^ 1 TOTAL SAMPLE IN-5001
[ ] DISTANCE FROM THE AIRPORT
A = 02 MILES (N=63I




i
-1
w
I
I — '






28






C = OVER 3 MILES iN-351)
25

14






fT

2,





16




10

rn
5 ft U
1 Flfi f¥un
15



„






9


15








^
1
^
ss



10


23




	 1



_


ABC ABC ABC ABC ABC ABC
AGGRAVATION US€D TO IT
  Figure 3.  "Usual" reactions to
              aircraft noise.
03-023

Volkov, A. M.
Karagodi na,  I. L.
Tsysar, A.  I.

Ail-Union Scientific Research  Institute of
Hygiene in Railway Transport /USSR/

THE ASSESSMENT OF RAILWAY TRAFFIC NOISE BY THE
POPULATION  (QUESTIONNAIRE DATA AND VERBAL
ASSOCIATION  EXPERIMENT)

Otsenka Naseleniyem Shuma Zheleznodorozhnogo
Transporta  (Po Dannym Oprosa i Slovesno
Assotsiativnogo Eksperimenta)

Gigiyena  i Sanitariya

No 2:29-32,  1971
Mass complaints of high noise levels from
the population  living near railroad tracks
near Moscow prompted a study on public reaction
to noise and resulted in a verbal  association
test.  Noise had become such a nuisance and
•distraction to  inhabitants that 87? of the
population filed complaints.

The neighborhood studied was broken down
into 3 areas, and noise levels in dBA recorded
for each:  1) 40-100 meters from railway lines,
with a maximum measure of 84 dBA;  2) 150-180
meters, measured at 67 dBA; and 3) 250-280
meters, measured at 63 dBA.

It was found that the most intense railway
traffic occurred between 1 and 5 am, which
resulted in sleep disturbance for the
neighboring population.

To measure subjective reaction to railway
traffic noise, questionnaires were distributed
among the inhabitants.  Of the 144 persons
living in the area 40 to 100 meters from the
railroad tracks, 126 (81%) complained of
intense discomfort and disturbance; 47-64?
reported interruption of sleep because of
intense traffic in the early morning hours;
and 21-45? complained that noise from the
trains and signals caused fright in their
chi Idren.
                                                           Inhabitants living 150-200 meters away from
                                                           the noise source reported less discomfort due
                                                           to railway taffic; about 50% had serious
                                                           complaints.  For those at a distance of
                                                           250-300 m the noise was even less disturbing,
                                                           though still  noticeable.

                                                           For an objective analysis of the effect of
                                                           railway noise on the population, a verbal
                                                           association test was given to 136 persons
                                                           living near the noise source.  Subjects were
                                                           presented with a list of general words,
                                                           interspersed with key words such as "silence,"
                                                           "train," "station," "transport," and
                                                           "sleeplessness."  Reaction time to key words
                                                           averaged out to 1 second longer than reaction
                                                    87

-------
04-001
                                               ECONOMIC ASPECTS
time to general  words, in all  groups tested.
This is in comparison to the control group,
which showed a 0.6 second difference in
reaction time.  The group closest to the
railroad tracks showed the most delayed
response time.  It was inferred from this
study that high noise levels have detrimental
effect on the central nervous system, and
cause a delay in response to verbal  cues
proportionate to the noise level.

Typical responses to the key words themselves
showed the influence of railway traffic
noise upon the public.  For instance, in
response to the key word "silence,"
almost 15% answered: "(it) will never be,"
"seldom," and "loudly."  To the key word
"sleeplessness, responses were: "often,"
"didn't sleep," "because of the trains,"
"because of the noise."

This study shows that high noise levels can
affect a community.  Even latent response time
in verbal  speech is affected,  indicating the
effects of noise on the central nervous
system.
Distance from
railroad tracks
(in meters)
                         TABLE  I

                    Maximum noise
                    level with
                    windows open
                       (in dBA)
Latent verbal
response time
to words (i n
sec)
                                    Genera I
                                              Key
40-100
150-180
250-280
84
67
63
3.3
2.7
2.4
4.3
3.7
3.4
    Control Group
                                     2.6
                                             3.2
                                                                meet at present.  On the other hand, a too
                                                                 lenient code  limits maximum permissible  noise
                                                                to 85  dBA at  100  feet.

                                                                 In quieting machinery, some negative factors
                                                                 involved are  increased cost, size, or
                                                                 ineffective work  and difficult maintenance.

                                                                The cost of mufflers for most hand-held  tools
                                                                 is from zero  to five percent of  the cost
                                                                of the unmuffled  tool.  However,  cost  for
                                                                the development of a paving breaker with a
                                                                built-in exhaust  muffler and built  in  force
                                                                cancellation  totalled over $300,000.

                                                                Drills without noise control produce about
                                                                 120 dBA at one meter, which can  be  reduced
                                                                to 100 dBA at a cost  increase of  10-15$,
                                                                and to 90 dBA at  an estimated cost  increase
                                                                of 30-40?.  The cost  increase of  reducing
                                                                compressor noise  from  110  dBA to 85 dBA
                                                                 (at one meter)  is about 30*.  For smaller,
                                                                gasoline engine driven units the cost
                                                                 increase  is about 10-15?.
04-002

Ostergaard, P. B.

Ostergaard Assoc., West CaI dwell, NJ

10 Glenwood Way

CAN INDUSTRIAL PLANTS BE ADEQUATELY QUIETED?

At: American Association For The Advancement
of Science, 138th Meeting, DEC 29, 1971

West Caldwell, NJ, Ostergaard Assoc.,  1971,
14p.
     04-001

     Diehl,  G.  M.

     IngersolI-Rand Research,  Inc.,
     Princeton, NJ

     CONSTRUCTION  EQUIPMENT-WHO WANTS  IT QUIET?

     At: American  Association  for the  Advancement
     of Science, 138th  Meeting, Philadelphia,
     DEC 29, 1971

     Princeton, IngersolI-Rand, 1971,  14p.
     One of the targets of noise control  legislation
     is construction equipment noise.   Noise control
     codes of various cities,  however,  are  either
     too strict or too lenient.   An example of
     the former is a code which  prohibits paving
     breakers from producing over 85 dBA  at a
     distance of 1 meter, an impossible standard  to
                                                             Industrial noise as discussed in this report,
                                                            can be divided into two general  areas of
                                                            concern.  One is the high noise levels within
                                                            factories.  The other is the noise which a
                                                            factory radiates to the community and which
                                                            annoys people residing near the plant.

                                                            When a factory becomes a community noise
                                                            nuisance, legal  action can be brought against
                                                            it by annoyed neighbors.  It is expected that
                                                            noise levels will be set by environmental
                                                            organizations such as the EPA.

                                                            Reducing the noise that radiates outside a
                                                            factory is discussed.  Enclosing the plant
                                                            prevents the escape of noise to the outside;
                                                            in doing this a closed loop air system
                                                            circulation is used with the added advantage
                                                            of purifying the air.

                                                            The installation of mufflers on fans and vents
                                                            outside eliminates noise at little cost.
                                                            Distance from neighborhoods, of course,  is
                                                         88

-------
                                            ECONOMIC ASPECTS
                                                                                                         04-003
always an important factor.   The best solution
to the noise problem is the  development of
quiet equipment.

The question concerning noise control is what
kind of costs are involved.   It is fairly cheap
to provide an employee with  ear plugs or
earmuffs.  The cost might run anywhere from
$5.00 to $10.00 for plugs or muffs and this
should provide around 30 to  35 dB of noise
reduction in the critical frequencies, if the
employee wears them properly.  This form of
noise control, however, may  not be particularly
cheap when the noise source  is one or two
machines and many, many employees are subjected
to the noise  levels.  These  costs work out to
be 25 to 30 cents per dB per employee protected.

Noise control for the path is harder to
estimate.  Barriers, for example, when installed
can be quite sizable in extent.  The cost of
installation may be about 50 cents per square
foot and the noise reduction in the order of
15 to 20 dB.  This means the costs will  be
something Iike 3 cents per dB per square foot
of the barrier.   To be effective, the barrier
may have to encompass 50 to  60 square feet
and the costs then run roughly $1.50 to $2.00
per dB.

A complete enclosure around  a piece of machinery
will probably provide twice  as much on a decibel
scale than a barrier, but the costs run around
ten times as much.  The benefit per employee,
however, can be quite high since all employees
will benefit from the noise  reduction of the
machine which has been enclosed.

The amount of noise reduction which can be
achieved using sound absorbing materials is
usually limited to something like 10 to 15 dB.
The costs will run something like 10 cents per
dB square foot of material.   Since it is
essential that practically all  of the interior
surface of the plant be treated with sound
absorbing materials, the cost can be quite high.
However, when it is distributed over all
employees, the cost might be quite low.

In figuring aii  of the costs above, no account
has been taken of the engineering work which
may go into studying the noise source, etc.

It's obvious that in the long term it is going
to be the purchase of quiet  machines in a plant
which will  provide the most  noise control.

The whole approach in the longer range future
can be summed up by the two  words: "buy quiet".
04-003

Paik, I.  K.

Urban Transportation Center,
Washington, DC

IMPACT OF TRANSPORTATION NOISE ON URBAN
RESIDENTIAL PROPERTY VALUES WITH SPECIAL
REFERENCE TO AIRCRAFT NOISE

Springfield, VA, NTIS, PB 1940101, AU6, 1970,
23 p. HC:$3.00 MF:95 cents
The purpose of this study is to establish some
statistical evidence on the effect of
transportation noise on residential property
value, especially on the value of residential
property in strictly residential  areas in
comparison to that in commercial  areas.

The study was made up of 2 parts:  The first is
an attempt to measure the impact of variations
in the level  of aircraft noise on residential
property values in the vicinity of John F.
Kennedy Airport.  The second consists of a
comparative evaluation of the noise effects
between the relatively commercialized
neighborhood in the same vicinity.

The technique used was the linear regression
method.  Data consisted of 162 observations
from the 1960 U.S. Census of Housing and
PopuIation.

In all models of the regression equation, the
noise  level turned out to be a statistically
significant factor.  The level of significance
was slightly higher for the residential area
compared to the commercial  industrial area.
The sizes of houses turned out to be the most
important price determining factor.

At this point, nothing can be said on the
validity of using the result for policy purposes
until  the study is completed and the predictive
capability of the model is tested.
04-004

Thomas, R. J.

W. S. Atkins & Partners, Epsom /England/

Environmental Development Group

TRAFFIC NOISE-THE PERFORMANCE AND ECONOMICS OF
NOISE REDUCING MATERIALS

Applied Acoustics

Vol  2 No 3:207-213, 1969
                                                    89

-------
04-005
                                                ECONOMIC ASPECTS
     The  cost  is  as  much  a  property of a material as
     are  its  physical  properties.

     The  cost  means  the total cost of the particular
     course of action.  An  example of the importance
     of  finding the  total cost  is a London office
     block which  is  being modified at the moment.
     It  is built  on  a  major traffic route and  in
     order to  reduce the  effect of traffic noise the
     owners decided  to install double glazing.

     The  double glazing costs $73,000 (supplied and
     fixed) and could  have  been installed with  little
     inconvenience to  the office staff.  However, as
     double glazing  really  works only when it  is
     closed,  air  conditioning was also necessary,
     bringing  the total expenditure to $624,000 and
     causing  considerable disturbance to the office
     staff.  Thus the  total  cost  is probably ten
     times the direct  cost  of the double glazing.

     After calculating the  cost the next step  is to
     compare  it with performance  in a meaningful
     way.

     There  is  a scale  already  in use for evaluating
     things which are  essentially different  in
     character and  it  is  well established and
     widely used; money.

     It  has proved possible to calculate the values
     which people put  on  subjective things.   It has
     been done for the particular case of houses
     subjected to noise,  etc. and  in principle could
     be  used  for  any loss of amenity.

     The  example  in  Fig.  1  shows how this kind of
     evaluation might  be  used  in deciding what
     action too take over the noise from a motorway.
     Of  the five  possible measures considered  three
     cost vastly  more  than  they would save in
     amenity  value and may  be eliminated from  further
     consideration.  The  remaining two possibilities
     appear to be worth while.
BASIC CONSTRUCTION FORM
(AT -GRADE MOTORWAY)
f=^ 1==T SB' 3 s' -"r^t 1=^:T
K 600' ."li" , 600' >(
Method of
noise
reduction
" 	 — ^_ 1
10(1 *cr»*ni
T__T
!S 1 rtic-n*d titling
-i^^J"
15rt r«-s f*d t-Uing

JSL
:v;;f., 6 —
»ii'°""_n
I.CII
noise
reduction
5 dBA

C dBA

11 dBA


404BA
30dBA



$^°b'o'o"le
130

5,220


5,350

13,050

390

amenity
va'.ue
fi nnn
310

390


700

1,300

522

                 KiB
                      LXc of cost and perfor
The office modification mentioned earlier
provided an example of this.  During "the
preliminary tests it was found that the noise
level  with the windows open for ventilation
reached about 74 dBA in the front offices.
Simply closing the original windows reduced
this to 61 dBA, which was easy enough to
measure.  However, when a secondary window
was installed the level dropped to 54 dBA and
internal noise (doors slamming, conversations
in the corridor, etc.) became noticeable.

The next step in the test was to seal  the
outside window as well.  This brought the
traffic noise level  down to 49 dBA and
measurement became almost impossible because of
the internal  noises, which followed one another
in an almost continuous sequence.

The internal  noises were caused by hundreds of
acts of minor thoughtlessness and by minor
defects in the construction of the
partitioning and in the maintenance of the
building.   Noise from such sources would tend
to give rise 1o dissension among the occupants,
whereas traffic noise coming from outside the
building had a unifying effect and provided a
bond between people in adjacent offices.
Consequently it was decided to leave the
windows unsealed.   In addition a sum of money
was earmarked for dealing with internal noise
problems as they became apparent.
     A fact which  is  often  missed  is  that  noise  is
     not necessarily  a bad  thing;  sometimes  it can
     be very desirable.
04-005

Hurlburt, R. L.

Inglewood Department of Environmental
Standards, CA

105 East Queen Street, Zip 90301

AIRCRAFT NOISE EFFECTS ON PROPERTY VALUES

Inglewood, CA,
City of  Inglewood, FEB, 1972, 2 H.
A study of property values  in  Inglewood, CA,
showed that residential  land values are
approximately 50? higher, and  rental dwelling
vacancy rates approximately 50%  lower  in areas
where aircraft noise  is  less than 80 PNdB
compared to areas where aircraft noise exceeds
110 PNdB.

The results were computed by a  linear  regression
analysis of data from the Inglewood General
Plan, Prelimirary Housing Element.  The data
from 21 census tracts, comprising the entire
city of Inglewood, were used for  land  values
and vacancy rates.  The corresponding noise
levels used were those at the  approximate mid-
point of each census tract.   Three possible
correlations with noise  levels were studied:
residential lend values, vacancy rate of
                                                         90

-------
                                                                                                         05-001
                                          BUILDING ACOUSTICS
rental  dwelling units,  and vacancy rate of a I
dwelling units.  The first two correlations
were significant at the 5? level.

Variable   Regression   R:computed  R05 Coef.
Y=Land     equation
value in   (corrputed!
$/sq ft
or vacancy
rate i n %
                        correlation required for
                        coef.        sign i f icance
                                    at 5?
                                    conf i dence
                                    level
Resi dentia I
land val ue
($)        r=5.02-.024x
                          0.5489
A I I  dwe Ming
vacancy rate
(%1         Y=0.22+0.43x   0.2766
                                    0.456
                                    0.433
Rental
dwe Ming
vacancy rate
(%)        Y=-1.29+.067x  0.4427    0.433
05-001

Sulewsky, J. E.

Goodfriend-Ostergaard Assoc., Cedar
Knolls, NJ

7 Saddle Rd., Zip 07927

ACOUSTICAL DESIGN GUIDELINES FOR OFFICE
LANDSCAPING

Sound and Vibration

Vol 5 No 6:17-18, 1971
at least 3/16 inch thick, to eliminate noise
such as foot shuffling.   Ceilings of "normal"
construction (thin mineral  acoustical  tile)
are not sufficient because their Noise
Reduction Coefficient (NRC), a measure of
average sound absorption, is only about
0.65 or less, but modifying the ceiling by
adding vertical  baffles  of glass fiber panels
can bring overall ceiling absorption up to
NRC 0.95.  Other successful ceiling treatments
have included:

1) a flat ceiling of glass fiber panel  with
an NRC of 0.95;  (2) an open light grid panel
with a plenum above it made of vertical
baffles or flat glass fiber ceiling panels;
3) coffer or modified baffle ceiling systems
made of glass fiber panels.  Because lighting
fixtures are assumed to  cover 25 percent of
the ceiling area, their   light diffusers
should be of the open rather than solid
type.

Walls, partitions and columns should be covered
with sound-absorptive materials such as fabric-
or vinyl-covered perforated glass fiber
panels.  Carpeting can also be used if  pile
depth  is at least 3/8 inch on jute backing.

Window draperies are essential; with 150
percent fullness and semi-open weave,  they
may still be translucent enough for exterior
objects and colors to be defined.  Screens
should be placed to eliminate  line of  sight
paths between seated personnel at different
work stations and around noisy equipment.
They should work most efficiently in the
250-2000 Hz range, which is the crucial
range of speech and business machine spectra.
They should be at least  2i inches thick, have
an impervious membrane in the middle to reduce
noise propagation through the screen,  and have
equal thickness of sound-absorptive material
on either side.
Open plan office arrangements are becoming
increasingly popular, but there can be problems
in providing necessary speech privacy between
work stations and in eliminating disturbing
noise from office equipment.

The three main principals that can prevent
significant  loss of acoustic privacy are:

11 jse of carpeted floors and sound absorbing
materials on ceiling and room surfaces that
could reflect sound from one work station to
another;

2! placing acoustic screens between work
stations and around noisy office equipment;

3) adding background masking sound through a
loudspeaker system to cancel transmission of
word information between work stations.

Carpets on + loors should have a pile height
of at least 0.156 inch and either be carried
on a separate sponge rubber or hairfelt pad
or have an integral  sponge rubber backing
                                                            Background masking sound  is produced
                                                            electronicly  through  loudspeakers hidden  in
                                                            or  above  the  ceiling.   Its frequency spectrum
                                                            is  designed to  match  that of speech and
                                                            although  it  is  audible,  its  level and
                                                            composition are such  that  it does not sound
                                                            ''noisy'1 to personnel.   Its purpose  is to
                                                            increase  speech privacy by reducing
                                                            intelligibility of speech propagated between
                                                            work  stations.   The background noise system
                                                            must  be tuned after  it  is  installed by
                                                            adjusting the level and spectrum of the
                                                            speaker system  for the optimum combination
                                                            of  masking and  quietness.
                                                     91

-------
05-002
                                              BUILDING ACOUSTICS
    05-002

    Heebink, T. B.

    United States Dept.  of Agriculture,  Seattle

    EFFECTIVENESS OF SOUND ABSORPTIVE MATERIAL IN
    DRYWALLS

    Sound and Vibration

    Vol 4 No 5:16-18, 1970
    Results of field measurements of four wall
    specimens in a small  apartment building showed
    that urea formaldehyde foam and mineral wool
    were effective sound  absorptive materials in
    wood-frame party walls.   Light-weight walls
    can thus be  provided  with a Sound Transmission
    Class (STC)  number of 50 or more.

    The foam used was the patented Isoschaum
    Process type.   Its three components are urea
    formaldehyde resin, a foaming agent and air.   It
    was applied  in the spaces between studs before
    the walls were faced  with gypsum board.  It
    firms in about one minute but continues to dry
    for one or two days.   The eellular
    charcteristics are 60? open cells.  The foam
    is nontoxic, self-extinguishing, non-corrosive,
    mold-resistant, and has a density of about 0.6
    Ibs per cubic foot.

    The walI construction was double 2x4 studs and
    plates with a space of 1/2 inch between both
    studs and plates.  This was faced with 5/8 in.
    fire-rated gypsum board.

    The four different filler treatments and
    their results were as follows:

                                   Field-tested  STC

    1) Wa I I fi I  led with foam on
    both sides  (foam 7 in. thick)        52

    2) Wall filled with foam on
    one side (foam 2^-5 in. thick)       50
    pI us resi Iient channels under
    one gypsum  facing.

    3) A 2  in.  blanket of mineral
    wool  in stud spaces on both
    sides of the wall  (total
    thickness:  4 in.), plus              47
    i  in. sound  deadening board
    under one gypsum face.

    4) WaI I f i I Ied wi th foam on one
    side  (foam  2j-5  in. thick) plus      47
    i  in. sound  deadening board
    under one gypsum face.

    The ratings  of the latter two walls were  limited
    to STC  47 by their poor performance at 160 Hz.

    There are other ways to get equivalent acoustic
    isolation in double-stud walls.  One way uses
    thermal  insulation as the filler material and
uses either resilient channels or sound
deadening board under the gypsum board on
both sides of the wall.

The in-place cost of urea formaldehyde foam
is higher than that of thermal insulation (in
the Seattle area).  Full-thick foam (6-7 in)
costs 30 cents per square foot and half-thick
foam (2j-5 in.) costs 16 cents per square foot
installed.

Similar investigation, made on the floor ceiling
construction, showed that 6 in. of foam or 3
in. of mineral wool, together with the other
components of the construction, produced about
the same  isolation.  All  measurements were
made according to ASTM standard E336-67T,
"Tentative Recommended Practice for Measurement
of Airborne Sound  Insulation in Buildings."
05-003

Verges, L. F.

Verges Consulting Engineers,  Downers Grove,
IL

5209 Lee Ave., Zip 60515

WINDOWS—THE WEAK LINK?

Sound and Vibration

Vol  5 No 6:19-21, 1971
For windows in exterior walIs of bui Idings
near airports, a systematic  design approach
includes forecasting the noise exposure,
determining the required insulation,  and
only then choosing adequate  materials and
construction details.  Adequate design
knowledge for external  windows has existed
for years.   Construction providing adequate
noise protection near airports is 15-20$
more expensive than ''standard" construction.
Builders' and clients'  insistence on
exterior windows cause the most serious
problems for the designer, because the
window, especially if operable, is the
''weak link'1 in the wall  construction.   For
this reason, many critical buildings  near
airports have no exterior windows.  If
exterior windows must be used the design
method below is sufficiently reliable for
small projects.   For large scale projects
professional acoustical  help is a good
safeguard.

To determine the probable external noise
exposure from aircraft,  the  straight-Iine
distance to the nearest airport apron
position (not to the edge of the airport
or to the nearest runway) must be
determined.
                                                         92

-------
                                                                                                  05-003 (CONT.
                                            BUILDING ACOUSTICS
The designer determines background
noise levels acceptable for the  various
rooms from the table below.   'Background"
level does not include the sounds of
human activity, but  includes  ventilating
noise, lighting hum, sound of air
conditioning units,  plus noise coming  in
from outside.  The table below  is based on
thousands of measurements of  what people
will accept, within  reasonable  limits  of
confidence (approximately 90?).

Maximum permissible  interior  background
 levels  in dBA
Type of
Bu i 1 d I ng
Hotel
or
Mote 1

Ai rport
Te rm i n a 1
Fac i 1 i ties
Office
Bui 1 di ngs
Room Max. Permissible
Interior Background
Level s-dBA
Bedrooms
Meeting Rooms
Offices
Lobby
Shops
Restaurants
Ticketing Areas
Restaurants
Main Waiting Room
Loading Gate Areas
Executive and
Pri vate Offices
45
50
50
55
55
60
60
60
70
70

45
                General  Office Areas   55
                Lobbies                 55
 Shoppi ng
 Centers
 Schools
 Apartments
Lobb ies
Stores
Restaurants

Classrooms
Gymnasi urns
Audi tori urns

Bedrooms
Kitchens
Living Rooms
 Hospitals       Patient Rooms
    &            Activity & Social
 Nursing  Homes   Rooms
55
55
60

50
60
40

40
60
50

45

55
Next the acceptable  interior level  is subtracted
from the anticipated  exterior noise level  to
determine the  exterior  wall  isolation required.
For example  if  exferior noise wi I I  be at
least 87 dBA (from  Figure  1),  and  the
interior background  level  for a  motel  bedroom
should be no higher than 45  dBA  (from the
table), 87 minus  45  indicates a  42 dB   barrier,
and the window  must provide  at least that
isolation.  Sound Transmission Class (STC)
numbers for various types  of window systems
provide a good  approximate method  of choosing
the correct window  treatment even  though they
were originally developed  to provide a single
number rafings  for  interior  partitions.   For
example, if 42  dB external  isolation was
required, it could  be provided by  a window
system with an  STC  42 rating.
Sound Pressure Level (dB A)
-nSSSSSSg















G. 1 .

\






^





s;






v





100
Distance to Loading Apro



\






s







X.,






k

1
1000 ' '
Position at Airport (Feet)




V

10,000 *
                                                             The table shows that a single pane of glass with
                                                             ordinary glazing is a poor sound barrier.
                                                             Spaced, double or triple glazed assemblies do
                                                             much better, but only if the space between
                                                             panes is more than one inch.  However, normal
                                                             glazing procedures often do not provide air-
                                                             tight edges, leading to severe acoustical
                                                             leaks unless installation is closely supervised.
                                                             Another draw back to spaced window systems is
                                                             their expense,  bulk, and maintenence problems
                                                             (interior soiling).  The laminated acoustical
                                                             glazing consists of multiple layers of thin
                                                             glass laminated with thick, soft layers of
                                                             polyvinyl-butyrate plastic.  The resulting
                                                             total pane thickness ranges from i" to over one
                                                             i nch.
                                                                             Sound transmission class ratings
                                                                            for various types of glass
                                                                   Class Type
                                                                                                     STC
Single Strength
Double Strength
V," Plate
V4" Plate
1" Plate
1" Insulating, lk" air space
Yt" Safety
9/32" Laminated Acoustical
W Laminated Acoustical
Spaced units, with air spaces from 2" to 4"
  19
  21
  26
  31
34-37
  32
  31
35-36
38-40
38-46
                                              In general, however,  there  should  be no
                                             operable windows  used,  whether of  the hopper,
                                             double-hung, or casement  type, if  performance
                                             better than STC 32  are  needed.  If building
                                             codes reguire operable  hoppers,  the hoppers
                                             should have double  or triple  edge  gaskets, at
                                              least two can-type  handles  or catches, and
                                             close tightly under considerable pressure.
                                             Even better, they could be  made only
                                             technically operable—that  is, openable only
                                             by a custodian with a wrench.
                                                      93

-------
05-004
                                               BUILDING ACOUSTICS
    05-004

    Nylins, S.

    Saab-Scania, Sodertalje /Sweden/

    In:  Jansson, P.G., Conferences in Connection
    with the  International Air Pollution Control
    and Noise Abatement Exhibition, Joenkoeping,
    Sweden, SEPT 1-6,  1971

    Joenkoeping, Sweden,  1971, 525p.  (p. 7:100-
    7:106)
     In this report an engineer from Saab-Scania
    Sweden gives the motor manufacturer's
    views of the part played by production
    env i ronmentaI poI Iut ion.

    During the past ten years, the need for
    active measures  in the field of environment
    protection has become  increasingly pronounced
    and this in turn has led to a rapidly growing
    proportion of development work being
    concentrated on making motor vehicles more
    suitable for the environment.

    When talking about noise made by vehicles,
     it is important to use figures obtained by
    the same methods of measurement.   ISO has
     issued instructions as to how the measurement
    of vehicle noise shall be carried out.  When
     regulations are drawn  up it is extremely
     important that they conform to international
    standards.  There may  be good reason for some
    extremely  large centers of population to
     introduce special regulations.

     Local sources of pollution can also be
     brought under control   by means of traffic
     engineering and  road planning.

     The most difficult vehicle noise to combat  is
     the noise made by diesel-engine vehicles.
     Although common  belief  is that exhaust noise
     is most dominant, modern silencers have
     brought exhaust  noise  below a level that
     would add to the total noises.

     Noise from the combustion process  passes via
     the engine crankcase to the surrounding air.
     This noise  is difficult to subdue.  Another
     source of noise  is the cooling fan, the
     noise level of which increases with engine
     rpm.  Induction  noise  used to be difficult
     to control,  but  this  is now silenced to such
     an extent that  it no  longer has any effect
     on the total noise  level.  The difficulty of
     suppressing  noise is emphasized by the fact
     that very  little is gained by silencing one
     source of noise.  The  noise occurring at
     speeds as  low as 40-50 km/hr begins to have
     an  influence on  the total noise  level.

     Less than 3% of the total number of vehicles
     in Sweden consists of  heavy vehicles.  Due
     to traffic restrictions and other traffic
     engineering measures,  noise from heavy
     vehicles has been further restricted.
     Buses, on the other hand, are among the
vehicles that" are frequently driven in
residential areas.  Saab Scania has
designed a city bus with a noise level no
higher than 74-76 dBA, according to -the
ISO method o* measurement.

Another example of the work done in reducing
noise is that represented by the refuse
collection vehicles developed.  By using low-
speed hydraulic pumps for driving the
machinery and by the use of special
insulation around the engine, gearbox and
refuse handling unit, Saab-Scania can make
refuse collection vehicles with a working
noise level cf around 75 dBA.

Heavy trucks can be driven quiter  if they
have larger engines.  One of the reasons for
this is that a more powerful engine enables
the truck to be driven in a higher gear.
This in turn means that engine rpm will be
lower at an equivalent road speed.

Present-day society is completely dependent
on road transport.  For all parties concerned
it is therefore of utmost importance that
regulations governing these important
environmental questions are of a uniform
shape and that technical  and economic
considerations are not ignored.
05-005

Kihlman, T.

Chalmers University of Technology
Goteburg /Sweden/

TECHNICAL CONSTRUCTION METHODS AGAINST  NOISE

In:  Jansson, P.G., Conference  in Connection
with the  International Air Pollution Control
and Noise Abalement Exhibition, Joenkoeping,
Sweden, SEPT  1-6,  1971

Joenkoeping,  Sweden,  1971, 525p.  (4:29-4:34)
Propagation of  industrial noise by means of
design changes  and extra devices on machines
is discussed.   It  is necessary to use
technical construction methods against  noise.

If a source of  noise is out of doors, the
reduction of  noise with distance  is most
effective over  the first few meters.  Large
reductions  in noise require  large protective
distances and in general noise from a source
out-of-doors  reaches very far.

The  intensity of reflected sound can be
affected by absorbents  in the room.  By
providing a room with good sound absorbents,
the  level of  the reflected sound can be
decreased by  5  to  10 dB, and a decrease of
                                                         94

-------
                                           BUILDING ACOUSTICS
                                                                                                         05-006
this size is not insignificant since it
implies a reduction of 25-50? of the
intensity actually heard.

Noise problems in industry cannot be solved
by means of sound absorbing material,
especially since the sound level near the
source where the direct radiation dominates,
is unaffected by absorbants.

Much larger reductions can be achieved by
means of sound-insulating  construction that
is airtight.  The most simple door in an
apartment has a sound insulation of about 15
dB.  The sound insulation  of  a 15 in thick
concrete wall is about 50-55  dB.  With frame
wall constructions, within a  range of 7-15 cm
in thickness, sound insulations in the range
30-55 dB can be achieved.

Sound screening arrangements  use screen as
high as possible, placed as near as possible
to the source.   In typical situations this
can give reductions of about  5-10 dB at
medium and high frequencies.

Vibration insulating of machines is often
necessary because of noise.  It involves
standing the vibrating source on springs.
In this way the transmission  of vibrations
to the foundation is reduced  above a certain
frequency.  It is necessary that the
foundations be heavy and rigid.

When technically planning  industries and
industrial premises with respect to noise
problems, these guidelines can be followed.
Noisy machines and processes  should be
separated not onty from those activities
which require silence, but above all  so that
one avoids exposing more individuals to noise
for longer periods than one must.  For
industries which have appreciable parts of
their activities out of doors, much can be
gained by screening and by enclosure.
Industrial premises should be provided with
effective sound absorbents.  The absorbents
must naturally be suitable for the particular
environment and be suitable from a practical
point of view.  The size of sound insulating
constructions is not generally a problem, but
physical  presence can be restrictive.  This
can mean that industrial premises should be
made somewhat larger so that  space is
available for dividing walls  between various
parts of the operations.  Finally, with
respect to vibration insulation, even this
starts at the constructional  planning stage.
Building planning in general  and constructive
design in detail  are important here.
05-006

Gardinier, R. E.
Nordby, K. S.
Si Isbee, D.  L.

International Business Machines, Endicott, NY

ACOUSTICAL FOAMS FOR SOUND ABSORPTION
APPLICATIONS

Sound and Vibration

Vol 4 No 7:12-16, 1970
The physical and acoustical properties of
polyurethane foams were investigated for
sound absorptive wedge applications for semi-
anechoic rooms.  (Wedges, several ft long, are
used on walls and ceilings of acoustical
measurement chambers to make the inside
surfaces of the chamber as completely sound
absorbtive as possible; sound is bounced
back and forth in the spaces between the
wedges, and practically none is transmitted
back into the main chamber space.)

Polyurethane wedges can give better
acoustical  performance than glass fiber
Although most of the investigation  concerned
the wedge application, with emphasis on low
frequency performance, some aspects of the
results are of general interest.

There are many types of foams on the market,
of varying  rigidity.  Polyurethane  flexible
foams can be divided into polyester and
polyether.   types.   The following table
compares their physical properties:

Criterion    Polyether    Polyester
Hydrolysis
Ultraviolet
Air f low
FIammab i Ii ty
More stable
in h urn i d
envi ronment
More durab le in dry
env i ronment
                          More stable;  used
                          almost exclusively
                          by garment industry
 Max 90?     Max
 open eel Is
                                  open eel Is
                                                           Cost

                                                           Fatigue
 Neither type self-extinguishing,
 except with additives at time
 of foaming.  The flame retardent
 additives lower the air flow
 resistance.  Without additives
 polyester is less flammable.

               Less expensive

 More durable.  Used
 for seat cushions.
                                                           Air  flow resistance  is the most  important
                                                           parameter  in determining the sound absorptive
                                                    95

-------
06-001
                                                  MEASUREMENT
    characteristics.   It depends on the number
    of cell membranes  present and the size of the
    cells.  Polyurethane foam is an open cell
    foam, with  relatively few membranes present.
    For the wedge application, a cell count of
    45-50 per linear in is  best.

    Foams are easily obtained in densities of
    1.0-2.5 Ibs per cu ft,  and as specials up
    to 8.0 Ibs per cu  ft.  Most of the special
    properties found in the denser foams do not
    seem to improve acoustical absorption,
    however.

    Foams can be obtained in almost any color,
    but u-v light, sulphur dioxide, and nitrous
    changes cause discoloration toward a light
    yellowish brown.   If the foam is initially
    colored light yellowish brown, therefore, it
    will be less  likely to show changes over
    time.

    Although foam making is still as much as an
    art as a science,  it is possible to obtain
    foam with specific mechanical properties.

    Flat sheets of foam can exhibit a 95? normal
    incidence sound absorption above the frequency
    where a 1/4 wavelength  is shorter than the
    foam thickness.  To  increase absorption to
    99%, wedge shapes  must be used to make the
    bulk impedance  increase between air and foam
    more gradual.
     06-001

     Oesterreichischer Arbeitsring  fuer
     Laermbekaempfung

     1012  Vienna,  Stubenring  /Austria/

     TECHNICAL NOISE PROTECTIVE  CONCEPTS  AND
     MEASUREMENTS

     Laermschutztechnische  Begriffe und Messungen

     OAL-Richtl inie

     No 20,  DEC,  1969, 7p.
     A detailed definition  of  sound  and  loudness
     and terms  used in  their measurement are
     presented.  It is  noted that  at present,
     instrumentation alone  is  not  sufficient  for
     technically accurate measurement of noise.
     It also requires a working  knowledge of
     acoustical principles.   It  is suggested  that
     only equipment recommended  by the
     International  Electrotechnical  Commission
     be used for measurements.   A  I ist of such
     sound level meters is  given below.   It is
     further recommended that  equipment  be
     inspected  by the Federal  Bureau of  Standards
     and Measures every 2 years.
Measurements, as prescribed by the guidelines
for particular noises, should be taken at
least 1.2 meters above ground when performed
outside.  Inside rooms, they should be taken
at 1.25 meters above the floor, in the center
of the room.  The area in which the
measurements are taken should be free of
people and obstructions, and the microphone
should be located distant from the observer.
Weather condifions should be taken into
account for outside measurements.  For
example, wind can influence the noise level by
10 dB.
Manufacturer 1 EC-Pub I. Filter
& Type
Measur.
area
for A
curve
Weight
in kg
Bruel & Kjaer
(Denmark) Type
2205
2206
2207
2203
Imulse-
SPM2204
123
179
123
179

179
A
A
A
A

A
,B,C
,B,C

,B,C

,B,C,D
32-140
37-140
54-140
19-134

15-150
0.
0.
0.
2.

2.
,8
.8
,8
7

7
 Peekel N.  V.
 (Netherlands)
 Type  GRA
 &  buiIt-in octave
 band  fiIter    123
General  Radio Co.
 (U.S.A.) Type
 1565 A        123
 1561          179
 Rhode  &  Schwarz
 (Germany)  Type
 ELT  BN4514    179
 Phi Iips  N.  V.
 (Netherlands)
 Type  PM  6400   123
                                                                 L.E.A.  (France)
                                                                 Type  SST  2     123
                                                                                        A,B,C   20(25)-  4.7
                                                                                                150
A,B,C   44-140  0.8
A,B,C   31-1501 2.5
                        A,B,C    55-120   0.6
A,B,C   38-130  2.1
                        A,B,C    24-140   1.5
                                                         96

-------
                                                                                                         06-002
                                              MEASUREMENT
06-002

Baade, P. K.

Carrier Corp. ,  Syracuse, NY

COt-ilROl OF NOISE FROM MACHINERY

In: Crocker, M., Proceedings of the Purdue
Noise Control  Conference, JUL 14-16, 1971

Lafayette, Purdue Univ., 1972, 594p. (p.  81-83)
Proposed methods and problems encountered in
efforts to measure noise from machinery are
discussed.  The need to standardize methods
for this measurement is stressed,  as are
differences in the requirements for different
kinds of machinery and applications.

There are alternative ways to present sound
data for a specific machine in five separate
areas.
1) Sound power versus sound pressure:
piessure describes conditions at the listner
location, power is necessary in accounting
for different transmission conditions.
2) Single number versus spectrum:   data
for noise control  must provide frequency
information.   Octave band spectra  generally
are sufficient by 1/3 octave band  spectra
may be necessary.
3) Frequency weighting: the A-scale is the
simplest and most common.  However, other
weighfing methods, which correlate better with
subjective judgements of unsteady  noises and
sounds, may be better suited for labelling
of consumer products.    >
4) Increments and accuracy:  the increments in
which noise ratings are given must be consistent
with the accuracy of the measurements on which
they are based and with human reaction scales.
5) Certification:   it is desirable for sound
ratings to be certified and policed, which
can only be done effectively by trade
associ ations.
06-003

Botsford,  J.  H.

Bethlehem Steel  Co.,  PA

Zip  18016

PROPOSED AMERICAN STANDARD FOR COMMUNITY NOISE

At: American  Association for the Advancement
of Science, 138th Meeting,  Philadelphia, DEC
29,  1971

Bethlehem,  PA, Bethlehem Steel  Co.,  1971,  4p.
A working group of a subcommittee of the
American National Standards Institute (ANSI)
has developed community noise standards for
community sampling procedures and for equipment
noise measurement, and is planning to draft
a model noise ordinance.

This group, the Working Group on Measurement and
Evaluation of Outdoor Community Noise, was
established by the Sectional  Committee on
Bioacoustics of ANSI.  The ultimate goal
is to achieve maximum human privacy from
intrusion by noise.  The first step toward
this goal is the capacity to define the
acoustical quality of the environment
in terms of prevailing noise levels in a
reliable and repeatable way.   A simple,
inexpensive technique is needed that may
be used by the non-specialist.  Therefore,
an A-weighted sound  level meter was chosen,
to be used on the slow meter response.  One
problem in measuring community noise is that
it varies considerably with time because
of aircraft, vehicular traffic and other
variable noise sources.  To get a repeatable
estimate, the following procedure is suggested:

The A-scale reading  is observed for five seconds
and an estimate of the central tendency is
recorded, as we I  I as the range of the meter
deflections.  Readings are repeated until  the
number of readings equals or exceeds the spread
in decibels of all the readings.  The average
of a I I  the readings will  be considered the
community noise  level for that  location.
Observations should be carried out under
similar conditions on each of three different
days.   At least five different  locations must
be measured before readings may be considered
typical of a neighborhood.

The equipment noise  measurement standard
proposes a test-site method for determining
the maximum noise emitted by public conveyances,
motor vehicles,  including recreational
equipment, and construction and industrial
machinery.  The  test site consists of a flat
outdoor area with no reflecting surfaces or
obstructions within  150 feet.   Seven categories
of equipment each have specific operating
instructions to  insure maximum  noise output
during testing.  These categories are broad
enough so that almost any device will fit  into
one of them.  The A-weighted sound  level meter
is used on the "fast response".

Vehicles that travel over 10 mph are tested
while moving.  They  are driven  by the microphone
at a distance of 50  feet with wide open
throttle at near-maximum engine rpm.  The
gear is chosen so that the speed stays  under
35 mph.  The vehicle passes by  in both
directions, and only data from  the noisiest
side is used.

Other equipment  is tested at a  standstill
while being operated at maximum noise
conditions.  The sound level   is measured
around a circle  50 feet from the equipment,
and the highest  sound level is  recorded.
To insure repeatibi Iity, the same method
                                                    97

-------
06-004
                                                  MEASUREMENT
     is used as for community noise readings.
     When a given model of equipment  is being
     type tested, different units of  that model
     are tested until the number tested equals
     or exceeds    s range in decibels of the
     individual     ,• results, and the average  is
     then taker   -   ie maximum sound  level of
     that mode       's method is intended for
     certifica       'Sting by the manufacturer and
     conformanc     .I1 ing by communities, but  is
     not Intends^  :or enforcement purposes
     except at a qualified test site.

     The standards described above are still  in
     the draft stage, and the Working Group  is
     now revising them to meet some objections
     that have been raised.
    06-004

    Puzyna, C.

    TRAFFIC NOISE

    Halasy Komunikacyjne

     In:  Zagadnienia  Akustyczne w. Zakladach
    Przemyslowych

    Warsaw, Wydawnictwo Zwiazkowe Crzz,  1971
    311p.  (p.  136-141)
                                 Measurements were conducted throughout the
                                 various streets of Warsaw to determine the
                                 noise  levels.  Narrow streets,  like "Zabkowska",
                                 with width of about 20 meters containing
                                 buildings with 4-5 stories high  registered
                                 noise  levels up to 78 dB.  Wide  streets  like
                                 'Plac Uni i Lubelskiej" which is  120 meters
                                 wide and  contains buildings up to 7 stories
                                 manifested levels of 64 dB.

                                 Studies were also conducted on greenbelts
                                 containing various trees and shrubs.  The
                                 results showed that greenbelts with taller
                                 trees and thicker shrubs reduce  the noise
                                 levels considerably.   For instance, 2 rows
                                 of poplars, 7 meters high and planted 3
                                 meters apart, with a row of fruit trees and
                                 a  living  fence in front of them, totaling
                                 15 meter  depth of the greenbelt, can
                                 reduce the noise level  up to 30  dB (with
                                 trees containing leaves), and 18 dB-
                                 (without  leaves).

                                 A  method  for noise reduction of  streetcar noise
                                  is the "wetting" process of tracks.   Results
                                 showed that noise  levels from tracks  on  concrete
                                 ranged from 82-85 dB after wetting, 73 dB on
                                 asphalt background and 60 dB on  a concrete
                                 plate with elastic insulation.   These
                                 measurements were taken  at a 7-10 meter  distance
                                 with the  streetcar going about  25-30  km  per
                                 hour.

                                 The author suggests  installments of street
                                 microphones which will register  excess noise
                                  levels by special monitoring.   This method
                                 will aid  the abatement program.
     Warsaw,  like  any  other  city, considers traffic
     noise  next  to industrial  noise,  its biggest
     noise  source.

     The  first step  in noise education should be
     undertaken  in city planning  and  siting.  Also
     greenbelt and parks,  according to the author,
     can  prove to  be the most  effective abatement
     device.   They should  be constructed along the
     main arteries,  along  street-car  and
     railroad  tracks and in  all heavy traffic areas
     of the city.   Any type  of a  green oasis should
     also be considered an essential  for school and
     hospital  areas.

     Another source  of noise abatement should be
     time restriction  put  on certain  railways.

     The  highest noise levels  are emitted  by trucks,
     streetcars  and motorcycles,  for  instance:
     Type of  vehicle

     Streetcar
     Tractor (No.  Ursus 45)
     Truck
     Trolley  car
     Motorcycle
     Bus
     Passenger car
Noise level  in dB

      63-78
       84
       77
       75
       76
       75
       60
     Measurements were conducted at a 6 meter
     distance.
                                  06-005

                                  On:   PNEUMATIC EQUIPMENT NOISE TEST CODE

                                  Sound and Vibration

                                  Vol  5 No 2:4,  1971
A recently prepared test code specifying
standard techniques for measuring sound from
pneumatic equipment covers both portable
equipment such as hand-held pavement breakers
and trai lor-mounted air compressors found on
construction sites, and stationary equipment
like large rotary vane compressors found in
industrial plants.  The document, "CAGIPNEUROP
Test Code for the Measurement of Sound from
Pneumatic Equipment,1  was developed by the
Compressed Air and Gas Institute (CAGI) in
cooperation with the European Committee of
Manufacturers of Compressed Air Equipment
(PNEUROP).
                                                          98

-------
                                              MEASUREMENT
                                                                                                         06-006
In the code, pneumatic equipment is divided
into three classes:  1) small  machines, both
percussive and non-percussive; 2) large
portable equipment; and 3) large stationary
equi pment.

Two types of measurements are taken, A-weighted
sound levels and octave band sound pressure
levels,  at each of five or more specified
locations one meter from the outline of the
machine.  For large portable equipment,
readings at 7 meters are also required.

During measurements, the equipment must be
stationed above a hard plane (e.g., a concrete
floor) and operated under specified loads.
Noise radiated from any loading device used in
conjunction with the equipment must be at  least
10  dB lower than that from the equipment, to
insure that only the latter is being measured.

One measurement problem in enclosed areas  is
reflected sound.  The code solves this problem
by  specifying that the levels at the
measurement point be at least 6 dB greater in
each octave band than  levels measured at
points more distant from the equipment.

Another measurement problem dealt with by the
Code  is the likelihood of large errors when
strong pure tones are present; these errors
occur because of  interference between direct
sound waves and those reflected from the floor.
This problem is solved by moving the microphone
vertically over a range of 30 cm above and
below the measuring point, at a rate of at
least once over the path per second, while the
measurement is being made.

Calculation rules and standard test data forms
are provided in the Code, which has been
submitted to International Standards
Organization (ISO) and American National
Standards  Institute (ANSI) for approval as a
standard.
Noise in the home  is not just an acoustical
problem; it is economic and social as well.
Legislation on noise control is not needed as
much as is the cooperation of industry in
manufacturing quieter machinery.

In order to achieve this cooperation for
effective noise control, information is
needed  in three categories:

1) equipment sound ratings
2) proper application and  installation of
equi pment
3) appropriate noise levels for specific
situations

Standardized methods of sound rating have
been started by the Ai r-Condi t ioni rig and
Refrigeration Institute (ARI),  which is now
publishing a directory  containing acoustical
ratings of outdoor condensing units.

It has also published an Application Standard
to aid the buyer to use these ratings for
selection and application of air-conditioners.
These ratings should aid both the buyer and the
manufacturer find should spread  in their
applicability to other machinery and equipment
as we I I  .

ASHRAE  (the American Society of Heating,
Refrigeration, and Air  Conditioning Engineers)
is updating its Standard 36 and is working on
the development of international  standards.

Social  and economic factors enter the fie'd of
noise control.  Individual  tolerance of noise
and willingness fo pay  for its control  also
have to be considered.

The publication of universal noise standards
is a step in the right  direction, but the
price and performance of quiet equipment will
have to be improved, too.
06-006

Baade, P. K.

Carrier Corp., Syracuse, NY

Research Division, Zip 13201

HOUSEHOLD NOISE PROBLEMS

Journal of the Acoustical Society of America

Vol 50 No 5:1232-1235, 1971
This article discusses recent standards for
performance ratings and application information
of the Air-Conditioning and Refrigeration
Institute  as an example of what an industry can
do to communicate acoustical  data between
manufacturers,  ins+aliers and users.
06-007

Hurlburt, R. L.
Owen, D. A.

Inglewood Department of Environmental
Slandards, CA

105 Easr Queen St., Zip 90301

PERMANENT MICROPHONE MONITORING SYSTEM

In:  Hurlburt,  R.  I.,  Inglewood's Noise
Monitoring Program.  Report on Phase I

Inglewood, CA,  City of inoiewood, SfPT 30,  1971
33p.  (p. 5-8, 38)
                                                    99

-------
06-008
                                                  MEASUREMENT
    A description of and  results obtained from a
    four-point automatic  noise monitoring system
    in  Inglewood, California  is presented.  The
    system measures noise from aircraft taking off
    and  landing at nearby Los Angeles  International
    Airport.  The four remote microphones are bolted
    to telephone pol«- ^rossarms about  25 teet above
    the  ground and are connected via brcadcast-
    quality telephone lease  lines to City Hall,
    wher° the data is processed.

    "fr",-,f~ 'pi   points monitor ro'i-e oon + i nj jus i v
    to show  U..ng tern rioise B/posure trends.  The
    microphones are rain  and wind protected, with
    an  integral calibrating system.  Upon command
     . 1000 h. -icj'iMl  magnetically drive;, the
    microphone equivalent to a sound pressure level
    o' 90 dB.

    At City Hall information is displayed on a
    Noise Exposure Monitor that presents the
    total time that noise in the area  around
    each mioiophone exceeds thresholds of 30, 90,
    and  100 dBA.

    "fher modes of data presenta+'on are available.
    1) An unweighted signal played to  r?,pe  'ecorder
    enables o record c c the noise  it'-el* to be kept,
    and  also a   ."> rcade if
    desired.
    2) The unweighted noise car, be monifored with
    loudspeaier to check  if  it iray be  caused by
    some source other than airp. lanes,  such as
    +rucks or motorcycles.   In pract ce, noise
    above 90 dBA usually  comes from aircraft.
    31 The ,-V-weighted noise  is played  to a
    graphic recorder which plots it against time,
    this permitting calculation of CMEL (Community
    Ncise E^Dosure Level) fiau^es.
               was checked out during a mor1toning
               eotember, 1970.  Also  in December,
               clerical consul ring firm did a more
               ed analysis of nine recorded flyover
               no. computer calculation techniques
               suits  in dBA, SENEL, and EPNI units.
               results  in dBA correlated «i"hin 2
               ewood's  data, showing that
                system  correlates ve'~y wH I with
               oated  measurement techi' iqu -AJ
    06-008

    ",eh i , '

     Innersoll-Rand Research,  Inc., Princeton, NJ
Instruments used for sound measurement and
the function of each are discussed.  The
basic instrument is 1 he sound level meter.
It consists of a nonairectionaI  microphone,
a calibrated attenuator, an amplifier, an
indicating meter, anc weighting networks.
The meter reading is in terms of root-mean-
square (rms) sound  pressure level.  The
instrument cannot measure the peak  level
of high-speed sounds, as those produced by
hammer bfows, punch presses on gunshots.
Special  i ns n umen t a f i o>  \f  require' f°r su'i-h
appIicat ions .

Usually, three weighting networks are  included
in these instruments—A, B, and 0.  Originally
ihe A network was to be used for sounds below
55 dB, tne B network for sounds between 55 ana
85 dB, and C for levels =bove 85 dB.  The
A network gives a very good indication of the
loudness of sounds  regardless of the  level
and is most irnporrant.   Ihe C network  is
essential ly flat, arid sounds read with if are
called sound pressure  levels.  AM  freguency
analyses mus+ be measured on the C  scale.
The A network reported as dBA fa I  Is of^
sharply at lov/ frequencies, to correspond to
the response of the par.  The microphone  is
the most important  part of the sound-
measuring iris r.Jmen1 a 11 jn .  frequency  response,
sensitivity, directio la I ity, and range are
primarily determined ^y the microphone.
The octave-band analyzer is the most common
analyzer for  ndustrial noise measurement.   it
separates the complex noise into frequency
bands one octave in width, and measures the
level  in each of the bands.  Narrow-band
analysis must be performed when the source of
a noise component must  he identified  for
purposes ot sound reducfion, or some other
reason,  for ~hese  analysis, half-octave,
third-octave and tenth-octave analyzers are
used.

An acoustic calibrator fits over the
microphone and calibrates the entire  system
of microphone, attenuator, amplifier,  and
meter.  The microphone should be shielded by
a wind screen when  wind veloci ly is high.
Noise recorded for  analysis in the  laboratory
can be analyzed with various band-width
analyzers, displayed on a graphic chart, and
retained for other  purposes if desired.
However, recording  supplements, rather than
replaces, Directly  measured d^ta.

Microphone placement depend^ upon objective,
noise at a workers  ear, of a cornpresser
inlet, e+c.  /it each of !"he microphone
locations, the following data 'houid  be
Taken with the machine operating:   1)
oprnll sound  level using  rhe A-woig-i * i rg
network; an.', .:' oc. tave-baiid sound  pressure
levels using Ihe flat  response or C network.

A similar set of data, background  noise,
should be taken at one ot the locations wirh
the machine shut down.   A sketch should be
made  showing the mct<-!ii  nc ,  locations of other
                                                         100

-------
                                                                                                            06-009
                                               MEASUREMENT
machinery building walls,  and microphone
locations, as well as  a  description of the
machine and operating  conditions.

Certain calculations are required  to
interpret data taken  in  sound tests.  It is
often necessary  to combine sounds  made by
different machines, or even octave-band
data measured on  the same machine.
Background noise  often must be subtracted
from the total noise to  obtain the sound
pressure  level of a machine alone.
06-009

Diehl, G. M.

Ingersoll-Rand  Research,  Inc., Princeton, NJ

THINK QUIET:  PART IV—NOI SE CRITERIA

Compressed Air  Magainse

Vol 76 No 5:12-13,  1971
Preventing  community  complaints about noise
from  industrial  sources is discussed.  Criteria
to prevent  annoyances are more restrictive than
criteria to prevent hearing damage or speech
interference.   Annoyance depends upon the
level of the offending noise compared to the
pre-existing background level, its absolute
value,  its  frequency, how it varies with time,
and whether it  occurs during the day or night.

While  it is impossible to predict exactly the
response from any  particular neighborhood
to any specific  noise, a fairly reliable
method has  been  developed by Stevens,
Rosenblith,  and  Bolt.  One can plot the
measured octave  band  sound pressure levels on
Figure 1 to determine the initial  level  rank.
The highest zone into which any of the octave
band  levels penetrates is the level  rank of
the noi se.
                RESIDENTIAL NOISE LEVEL
 Corrections are next applied as follows:

 CONDITION                       CORRECTION
 Pure-tone components                +1
 Wide-band noise                       0
 Impulsive                           +1
 Not impulsive                         0
 Continuous exposures, to
   1  per mi nute                        0
 10-60 exposures per hour            -1
 1-10 exposures per hour             -2
 4-20 exposures per day              -3
 1-4 exposures per day               -4
 1  exposure per day                  -5
 Very quiet suburban                 +1
 Suburban                              0
 Residential  urban                   -1
 Urban near some industry            -2
 Area of heavy industry              -3
 Nighttime                             0
 Daytime only                         -1
 No previous conditioning              0
 Considerable  previous conditioning  -1
 Extreme conditioning                -2

•The sum of the various corrections then  is
 applied to the original  level rank to obtain
 the corrected level  rank.   The expected
 community response can then be predicted  by
 Figure 2.
                   COMMUNITY RESPONSE  TO NOISE
     Community
     Action
     Threats of
     Community
     fiction
     Widespread
     Complaints
     Sporadic
     Complaint*
     No Observed
     Reaction
                      c    d   e   f    g
                      COMMUNITY NOISE RANK
                                       Figure 2
                NOISE CRITERIA (Nc CURVES)
                  OCTAVE PASS BANDS (HI)

                      MTTT
                                                                                               NOT RECOMMENDED
                                                                                                    ANY OFFICE
                                                                                                ^ LARGE
                                                                                                -1 FNUNFERiNG
                                                                                                   D DRAFTING
                                                                                             --- — - ROOMS
                                                                                            -.«,   PRIVATE OFFICES
         63   125   250   500   IK    2K   4K    BK
             OCTAVE-BAND CENTER FREQUENCY (Hz)
                                      Figure ]
                                                                                                   Figu.a 3
                                                     101

-------
06-010
                                                  MEASUREMENT
    A widely used set of noise criteria for various
    offices, conference rooms, residences,  and the
     like was developed by Dr. Leo Beranek (Figure
    3.)  The International Standardization
    Organization also has recommended a similar
    set of criteria, called NR (Noise Rating)
    curves.  The National Electrical  Manufacturers
    Association (NEMA) has produced a set of noise
    criteria for gas turbine installations.

    Precautions should be taken when  using  dBA
     levels.  The popularity of A-waighted sound
     levels is increasing rapidly as a means of
    expressing all  types of sound criteria,  whether
     it be hearing damage, speech interference
    levels, community annoyance levels, or
    machinery acoustic performance.  However,  it
    should be remembered that dBA  levels must
    be used with caution; whatever noise control
    must be engineered, octave band data are
    needed.  Sound should be combined on an
    octave band basis only, and not by adding
    or subtracting overall levels.
    06-010

    Organization for Economic Co-Operation
    and Development, Paris /France/

    Consultative Group on Transportation Research,
    2, rue Andre-Pasca I

    URBAN TRAFFIC NOISE:   STRATEGY  FOR AN IMPROVED
    ENVIRONMENT

    Paris, OECD, 1971, 166p.
    An Organization for Economic Co-Operation
    and Development report recommends international
    abatement measures for traffic  noise.   The
    sponsoring committee set two goals for public
    policy:   to prevent further increases  in  traffic
    noise,  and to roll  back present levels at an
    economically, technically,  and  politically
    feasible rate.  Limits on maximum noise at  the
    source  should receive priority  over limits  on
    method  of operation because they automatically
    bring more widespread benefits.  Source limits
    should  be at  levels consistent  with the
    technology available at the time,  but  should
    be made more stringent as improvements in
    technology permit.   Governments should promote
    production of quieter vehicles  by specifying
    them in their procurements, and with
    progressively more stringent limits that
    will  encourage research and investigation of
    alternate urban transportation  modes which
    offer a long term solution  to the problem.
    Measurement techniques should conform  to
    International Standards Organization (ISO)
    recommendations.   Governments should encourage
    control  of traffic noise by urban planning
    and highway engineering techniques such as
    rerouting noisy traffic,  better traffic flow
    to minimize noise from acceleration, zoning
and  land-use planning, location of new major
roads to take advantage of existing natural
acoustic barriers, more use of tunnels and
open cuts, better  location and sound  insulation
of housing, and development of alternative,
quieter modes of urban transportation.

Since motor vehicles move in  large numbers  in
international trade, government regulation of
vehicular noise limits should be  internationally
compatible.  The work done so far by the
Economic Commission for Europe (ECE) and the
Common Market (EEC) is clearly only the first
step.  Any internationally agreed-upon limits
should encourage reduction from current levels
and not merely underwrite the status quo.

Three chapters of technical  background
information summarize the nature of the
urban traffic noise environment,  effects of
traffic noise on man,  and methods of control.

The chapter on the urban environment discusses
the predominance of urban traffic noise,  its
peak/background structure, specific noise
sources, and noise level  factors  (weather
conditions, night driving, natural barriers,
speed, flow, ard density of traffic).

The chapter on effects of traffic noise
discusses subjective effects,  speech
communication, interference with  sleep, effects
on learning and task performance,  and immediate
and cumulative physiological  effects.

The chapter on noise control  discusses source
modification by vehicle type and subsystem;
operational modification  such  as  rerouting,
limitation of night operation, improvement of
traffic flow; transmission path modification
such as road design,  noise barriers, proper
siting of buildings, and zoning;  and
architectural modifications such as window
treatments and interior bui iding  layout.

There are two Annexes.  Annex One contains
current administrative and legislative
practices of OECD member countries Canada,
France, Italy, Japan,  Netherlands, Denmark,
Norway, Sweden, Switzerland, and the United
Kingdom.

Annex Two presents the directives of the
UN (ECE, Geneva) and the Common Market
concerning maximum noise  levels from
veh i cles.
                                                        102

-------
                                              MEASUREMENT
                                                                                                         06-011
06-011

Williams, C. E.
Pearsons, K. S.
Hecker, M. H.

Naval Aerospace Medical  Inst., Pensacola, FL

Zip  32512

SPEECH  INTELLIGIBILITY  IN THE PRESENCE OF
TIME VARYING AIRCRAFT NOISE

Journal of the Acoustical Society of America

Vol  50 No. 2:426-434, 1971
A discussion of the  large number of complaints
made about aircraft  noise and  its disruptive
effect on speech communication suggests that
a measure of speech  interference may be
useful for evaluation of the annoyance of
ai rcraft noise.

Usually the level at only one  point in
time  (the peak  level) or the average sound
pressure level, is used to predict the
amount of speech interference  that would
occur during an aircraft flyover.  Since
the sound-pressure level and spectral
contents of an aircraft flyover change with
time, such predictions are often inaccurate.
A meaningful definition of speech interference
should take into account both  the degree to
which speech is masked by aircraft noise and
the duration of such masking.

For various kinds of steady-state noises,
the amount of speech interference produced
is uniquely related to the Articulation
Index (Al).  There is some question,
however, as to whether relations established
for predicting speech intelligibility in
steady-state noise can be applied without
modification to a situation involving time-
varying noise.   The objective  of this study
was to determine whether the relation between
speech Intelligibility and Al  for time-vary!ng
aircraft noise is different from that for
steady-state noise.

The results show that, for a given Al, the
time-varying noise masked speech less than
the steady-state noise.

The magnitude of the difference cautions
against the use of relations established for
steady-state noise to predict speech
intelligibility in the presence of time-
vary ing noi se.

It is concluded that the relation between
word intelligibility and Al  for time-
varying aircraft noise is different from
that for steady-state noise.   There n\\\  be
an appreciable  disruption of contextual
speech when the peak level  of an aircraft
flyover exceeds 88 PNdB,  an  SIL (speech-
interference level) of 68 dB, or an A-
weighted  sound-pressure  level  of 76 dB.
06-012

Cohen, A.
Anticaglia, J.  R.
Carpenter, P. L.

Department of Health, Education 8, Welfare,
Ci nci nnati , OH

National  Inst.  for Occupational Safety and
Health,  1014 Broadway, 45202

TEMPORARY THRESHOLD SHIFT  IN HEARING FROM
EXPOSURE TO DIFFERENT NOISE SPECTRA AT EQUAL
DBA  LEVEL

Journal of the Acoustical Society of America

Vol  51 No 2:503-507,  1972
This study seeks some clarification of the
adequacy of dBA measures for rating hearing-
loss risks for assorted noises which may
display broad differences in spectral,
temporal, or other acoustic features.  Its
specific intent was to test whether sound-
level readings in dBA could suitably depict
the harmful ness to hearing from exposures to
noises differing greatly in spectral shape.

Three test noises having spectral slopes of
6 dB/oct, 0 dB/oct, and +6dB/oct provided
the test conditions of interest.  These three
noises were presented at a constant  100 dBA
level in three separate 30 min exposure
sessions to each of 11 male subjects, and
then presented again to the same listeners  in
three additional retest sessions.  Figure  1
shows the spectral shapes of the three noises
at the prescribed 100 dBA sound  level.  Also
noted in Fig.  1  is the frequency response
curve for the A-weighting network.   It is
relatively insensitive to low-frequency sound
energy.  This weighting curve  is most biased
against the energy contained in the noise with
the 6 dB/oct slope.

Temporary threshold shifts in  hearing served
to evaluate the  degrading effects of the
different noise  spectra on the ear.  Such
hearing thresholds were measured for pure-
tone frequencies 250,  500, 1000, 2000,
3000, 4000, 6000, and 8000 Hz.   Each tone
was presented for 30 sec in which fime the
subject controlled the attunuator so as to
fluctuate about his threshold  level  for that
sound.  The attenuation rate was 4 dB/sec.
During the postexposure test, the listener
was allowed to stabilize his 500-Hz threshold,
beginning at 1-1/2 min after noise cessation,
the actual  posrexposure test commencing at 2
mi n.
Temporary-tnreshold-shift data for the various
pure-tone frequencies were corrected to
postexposure measurements at 2 min,
abbreviated as TTS2.
                                                    103

-------
06-012 (CONT.
                                                  MEASUREMENT
    If dBA is a satisfactory  indicator of  noise
    hazard to hearing  it would be expected that
    equal dBA exposures to the test noises,
    despite their spectral variations, should
    cause equivalent amounts of TTS2.  Spectral
    differences among the noises caused no
    statistically significant differences  in
    threshold shift wh.-sn pooled for all pure-tone
    frequencies.  Over-all TTS2 means for  the
    various noise spectra were nearly identical
    with mean differences less than 0.5 dB.

    However,  significant  interactions between
    noise spectra and pure-tone test frequencies
    were also found.  At pure-tone frequencies
    below 3000 Hz, frequencies above 3000 Hz, the
    reverse was true; the +6 dB/oct noise caused
    more threshold shift than the 0 dB/oct noise
    which, in turn, caused more TTS2 than  the -6
    dB/oct noise.  The -6 dB/oct noise is more
   harmful  to hearing than the other two test
   noises  for equal  dBA exposures.  Perhaps the
   weighting  curve for dBA is too severely biased
   against low-frequency energy, and thus does
   not  adequately take account of its degrading
   effects on hearing relative to that caused by
   high-frequency sound.  The +6 dB/oc slope
   noise  should be most harmful to hearing
   followed by fhe -6 dB/oct slope noise and the
   flat spectrum noise.

   In short,  dBA ratings of noise hazards to
   hearing may be discounting too much low-
   frequency  energy.  Except for one procedure
   which  simply averaged the sound levels of
   octave  bands with midfrequencies 500, 1000,
   and  2000 Hz, other noise rating schemes using
   spectral determinations did not improve on the
   amount of  TTS2 produced by the test noises of
   variable spectra.
                          &3
                                 "?50   500  1U03  ?OOC  400O 6000
                               BArD CIMER FREQUENCY 'N HZ

                           100-dBA NC'SE WITH RISI'v. SPECTRUM
      125   25O 500  IOOO  2000  «OOO  8000
         FREQUENCY IN HZ

SOUND-LEVEL METER A-B-C FREQUENCY RESPONSE
                                                         104

-------
                                                                                                         06-013
                                              MEASUREMENT
06-013

Langdon, j.

Building Research Station, Garston /England/

TRAFFIC NOISE CONTROL CRITERIA

Bui Id InternationaI

Vol  2 No 6:26-30, 1969
The pecularities of traffic noise are
characterized and the essential  pre-conditions
for a useful noise nuisance criterion
outlined.  The nature and origin of the
Traffic Noise Index (TNI) developed by
building research studies are discussed,
and comparison is made with the equivalent
noise level (END as an alternative method
of devising such criteria.

Numerous efforts to relate traffic noise
level to human response have failed to produce
measures with real predictive value.

tn order to measure and control  traffic
noise nuisance, there are at least three
points to  consider.  First, noise produced
by traffic  is exfremely varied  in both
intensity  and character.  Second, its
propagation is complex and imperfectly
understood.  Third, there are great
differences between individuals in the
degree to  which they can tolerate noise.

A practical noise control criterion must be
based upon  correlations between measured noise
and social  nuisance, resulting  in a functional
relationship which permits the  interplay of
all the  relevant  variables correctly weighted.

Two methods are discussed:  the technique of
the ENL  and the method of the (TNI) developed
by Building Research Station.   In short, the
ENL  is the  mean of a logarithmically weighted
summation  of all  noise  levels at 5 dB
i nterva I s .

In developing the TNI,  variations of traffic
over 24 hours were taken into account by
noise sampling, over an adequate period, 1)
the relative attenuation bases by recording
noise at building facades over a wide range
of distances, and 2) individual  differences
by using a sample large enough to obtain a
normal distribution.  A multiple weighted
correlation was obtained to enable prediction
of social  nuisance with fair accuracy over
the range of noise climates.

In comparing the two measures, the TNI gives
greater weight to peak noise as against
background  levels, whereas the ENL tends
to give weight to situations in which
high noise  levels will  prevail.   Also,
the TNI  gives better predictions of
nuisance and disturbance of sleep during
the evening and night than between hours 1-5
in the morning.  This is important because
most sleep disturbance due to noise occurs
during the first hour of sleep.


Both  indices have their advantages and
shortcomings.  The most important requirement
for noise control, given the measure of social
nuisance, is to reduce the peaks and surges in
traffic noise.

Purely physical scales will not be useful in
noise control, since they measure only the
intensity.  Only indices such as the ENL
and the TNI  assess the degree of disturbance.
 07-001

 Department  of  Housing  and  Urban  Development,
 Washington,  DC

 AIRPORT  ENVIRONS:  LAND USE CONTROLS

 Washington,  HUD, MAY,  1970,  35 p.
 This  environmental  planning  paper  points  out
 some  of  the  problems,  methods  and  prospects
 for solving  a  variety  of  aircraft  noise
 problems  facing  urban  communities.

 The comprehensive  planning process  for
 compatible  land  use  and airport  development
 is directed  toward  achieving an  optimum
 relationship between an airport  and  its
 environs.  As  such,  planning for compatible
 land  use  in  the  airport environs and
 planning  for the airport  itself  should be
 integral  parts of  an areawide  comprehensive
 planning  program.

 The compatible  land  use approach must be
 related  to noise alleviation made  possible
 through  engine modification, aircraft
 certification, and  revised operational
 procedures.  All relevant avenues  must be
 considered and applied to the  problem in  a
 coordinated  fashion.   Research and  development
 efforts  on methods of  reducing noise at the
 source and modifying flight  paths  and
 operating procedures to bring  about  further
 reductions should  proceed simultaneously
 with  similar investigations of airport
 community land use strategies.

 The conflicting pressures for  both the further
 expansion of the air transportation  system
 and for  urban and metropolitan growth in  the
 United States are  so strong that further
 impact ion of airport environs  is almost
 i nevitable.
                                                     105

-------
07-002
                                               PLANNING & SITING
    Therefore, the use of innovative approaches
    to land use planning and controls for
    development, as well as  the proper application
    of existing controls, is urgently needed.
    Land use controls must apply also to the
    airport itself, in terms of maximum acreage
    and intensity of use, so that the airport
    is compatible with the area in which it is
    located and so that changes in the character
    of the airport and its operations do not
    continually expose new areas to noise.   The
    costs and benefits of airport development
    must be weighed against  those associated
    with incompatible neighboring uses.  Further,
    the costs and benefits of "on-the-ground"
    and "in-the-air" solutions must be assessed
    to develop a total program to reduce aircraft
    noise impact.
    07-002

    Schmidt, H.

    6079 Sprendlingen/Hessen,  Am Trauben 9

    LEGAL MEASURES FOR PROTECTION FROM AVIATION
    NOISE

    Stand der Gesetzlichen Massnahmen zum Schutz
    vor Fluglaerm

    In: Fluglaermtagung, Wiesbaden, MAR 17-18,
    1969

    Wiesbaden, Deutscher Arbeitsring Fuer
    Laermbekaempfung, 1969, 2 p.
    The Inter-parlimentary Committee, which is
    represented by a I I  Government factions,
    has presented its first draft as publication
    V/355 in 1966, dealing with all  air-traffic
    noise problems.   It intended to divide the
    vicinity around airports in three noise
    zones.  The average noise level  for Zone I
    should be about 72 dBA, Zone II, 67-72
    dBA, and Zone III,  62-67 dBA.

    There should be no construction of hospitals,
    orphanages, retirement homes, sanitariums
    and schools in any zone.

    In Zones I  and II,  there should be no new
    residences constructed; and Zone III  only
    residences with good sound-protection.

    Finally, it was proposed that owners of Zone III
    residences should be granted allowances for
    the insulation of their homes,  and restitution
    for landowners whose  land could not be used
    for construction.

    Financially, this plan was found to be
    unrealistic because the cost for the civil
    airports would amount to about $630 million
    and that of the military-airports $3.15
billion.  In September, 1968, a new draft
was drawn up.  Now there are only two zones,
Zone I  - noise level  can exceed 75 dBA
and Zone II  67 dBA.  In Zone I, residences can
only be constructed in populated areas with
special insulation regulations.  In Zone II,
all new construction  requires all insulation
regulations.  The cost is carried by the airport
owners, and  in case of military airports, by
the Federation.

The cost estimated for the civil airports is
from $10 to maximum $12.6 million, and those
of the military airports between $37-47
mi I I ion.

In addition, airports are required to erect
noise monitoring stations.   Also, local
commissions should be established as advisory
organs for the communities.   They should
comprise representatives from the communities
surrounding airports,  airplane owners,
Federal agency for air safety,  and Federal
organization against  aviation noise and the
Health Organization.

It is also necessary  to enforce certain noise-
reducing measures, especially in respect to
arrival and departure.  It is believed that
take-offs and  landings can be curbed during
the night time.
07-003

Stacy, E. F.

Building Research Station,
Garston /England/

Dept. of the Environment
Watford WD2 7JR

MOTORWAY NOISE AND DWELLINGS

Building Research Station Digest

No  135:1-7, 1971
 Introduction of the "10$ Level"  (L10), a
 single figure measure of traffic noise
 exposure,  is proposed for measuring  design
 purposes.  This unit  is related  to subjective
 reactions, in this case dissatisfaction with
 traffic noise.  The unit gives a fair
 correlation with dissatisfaction and makes
 the best  use of the current state of knowledge.

 L10  is the arithmetic average of the hourly
 values, over a weekday period from 6 am to
 midnight, of the  levels in dBA just
 exceeded  for 10? of the time at  one  meter
 from the  facade of a  dwelling.   The  practical
 application of L10 to traffic noise  control at
 housing sites  involves obtaining the noise
 exposure  by direct measurement,  by estimation
                                                         106

-------
                                                                                                         07-004
                                           PLANNING & SITING
from design data,  or by a combination of the
two.  The maximum level for LIO recommended by
the Noise Advisory Counci I  is 70 dBA.  To
apply this standard to all  new housing and to
existing houses affected by new urban motorways
is useful in reducing the nuisance of traffic
noise.

Where a road already exists,  noise exposure
is measured at the housing site, provided that
no major changes,  such as pulling down old
buildings which intervene,  are proposed.  The
measured noise levels should  be adjusted to take
account of any foreseeable increase  in traffic
flow on the road.   If the motorway does not
exist at the building design  stage, noise
levels are estimated.  Adverse wind conditions
should be the basis for design purposes,
even though more favorable conditions sometimes
prevai I .

Ground surface that is grassed or planted
(not paved in any form) will  absorb energy
at some frequencies from sound waves that
are propagated close to the ground.  For
propagation distances greater than about 20 m,
this absorption can reduce the noise exposure
level in a complex manner.

Traffic composition, particularly the proportion
of heavy trucks, sometimes affects noise  level.
However, in fairly fast, free-flowing traffic,
heavy vehicles and normal gradients have only a
minor effect on noise  levels.

Well-designed  noise  screens  can  sometimes
achieve  as much as 20  dBA  reduction,  although
 10  dBA  would be more typical.   It  is  an
advantage to put  it close  to the noise  source,
to  make  it as  high as  may  be practicable  and
of  adequate  length.  Buildings may themselves
be  used  as noise  screens for screening other
buildings.  However, the noise  levels behind
the  screen building  itself,  close  to  the  facade
facing  away from  the road  should take  into
account  that other buildings can reflect  noise
back  to  the otherwise  shielded facade.

To  be effective,  tree  belts must be wide  and
dense.   A width of at  least 50 m is  necessary
to give  a reduction of  about 10  dBA,  and  a high
proportion of  the trees  and shrubs must be
evergreen  if the  protection  is to be
maintained at  all  times of the year.

Every building gives to  its occupants some
measure of protection  from external  noise.  The
noise level inside an  uninsulated dwelling,
away from the windows, should be at  least
10 dBA  less than the outside level.   If the
external level  of 70 dBA cannot be met, it
may still be possible to restore a satisfactory
acoustic environment indoors by  improving the
sound insulation of the structure.

A method has been proposed for estimating
L10 due to free-flowing traffic for a
range of circumstances.  This exposure
level provides a basis for planning against the
noise from urban motorways.  Until  more
knowledge is obtained, it is suggested that
the same procedures may be useful  for other
free-flowing traffic.
07-004

Kraege, R.

Institut Fuer Schall- und Schwingungstechnik,
2 Hamburg 70, Fehmarnstrasse

AIRPORT NOISE AND ITS CONTROL

Flughafenlaerm und seine Bekaempfung

In: Fluglaermtagung, Wiesbaden, MAR 17-18, 1969

Wiesbaden, Deutscher Arbeitsring Fuer
Laermbekaempfung, 1969, 2p.
This paper discusses abatement measures
taken to reduce the noise from an air-freight
terminal in West Germany.

Initially an embankment was planned to be
planted with trees and was found to be
unsatisfactory due to the time it would
take for them to grow.  A sound protection
wall was constructed at the airport boundary and
all freight handling sections were confined to
a  large hangar.  By these means the noise  level
was reduced about  13 dBA at the adjacent
residential area.
07-005

Lane, S. R.

California Univ., Los Angeles

School of Arch, and Urban Planning
Zip 90024

FREEWAY AND HIGHWAY NOISES:  AN INFORMATION
BASE FOR URBAN DEVELOPMENT DECISIONS

Springfield, VA, NTIS, PB204434,  1971, 90p.
HC: $3.00 MF: 95 cents.
In the 30 by 50 mi le core area of Los
Angeles there are 350 mi les of freeways
causing almost continuous noise levels of
70-90 dBA in the five block wide strips on
either side.  Because of this, most new
proposed freeway routes meet active opposition
from the communities that would be affected.
Criteria should be developed for compatibility
of transportation routes with human activity;
                                                    107

-------
07-006
                                               PLANNING & SITING
    these criteria would relate the costs and
    benefits of noise reduction to impacted
    communities.

    Data for Los Angeles are presented for
    residential population densities, freeways
    and traffic volume patterns,  leading to
    calculation of the number of  residents near
    freeways.

    Cars and trucks on freeways are then
    considered as noise sources, and together
    with other considerations such as surface
    street traffic noise and noise reduction in
    buildings, this information is used to specify
    zones of intrusion.   Data from other U. S.
    cities and from the United Kingdom are
    i ncorporated.

    Much past work done on subjective response to
    motor vehicle noise has not succeeded in
    giving an accurate picture of the degree of
    annoyance individuals actually experience in
    the contextual  situations of their various
    daily activites.  One reason for this
    failure has been the artificiality of the test
    setting and the limited number of subjects
    used; another reason is that the descriptors
    of degrees of annoyance were chosen by the
    experimentor.  The research done by the
    Building Research Station in the United
    Kingdom avoided some of these pitfalls by
    using survey methods in actually impacted
    residential areas.

    Criteria for acceptable residential  noise
    limits from various sources,  including the
    City of  Inglewood Ordinance, and various
    standards widely used in Switzerland, England,
    and the Scandinavian countries are
    compared with each other, and with noise
    levels implicit in the California Vehicle
    Code.

    It is concluded that about one million people
    currently  live within four blocks of a
    freeway  in Los Angeles.  Traffic noise is
    likely to exceed 75 dBA within one or two
    blocks of a freeway, and 60 dBA within four
    blocks.  The latter figure is about  10 dBA
    above urban residential background levels
    where there  is no high level noise source.

    The freeway system will problably double
    to 750 miles by 1980.  Exact  delineation of
    impacted zones will  require detailed surveys,
    because  of complex sound propagation
    patterns caused by variations  in shielding
    and  reflection.  There is a need  in  Los
    Angeles  for a noise data system commensurate
    with the current  level of effort  in  other
    environmental activities.  Community
    resistance to expansion of the freeway system
    has  already  been effective, forcing
    government and  the transportation  industries
    to account for  the costs of noise production.
    A comprehensive decision/allocation  system
     is needed  to deal with the  problem.
07-006

Dobson, D. E.

South African Council For Scientific
and  Industrial Research, Pretoria /S.
Africa

NOISE ABATEMENT: THE NEED FOR A MULT I -
DI SCI PL I NARY APPROACH

Municipal  Administration and Engineering

Vol 36 No 430:1971
The first committee on noise abatement in
South Africa was established in 1969 by the
Johannesburg City Council.  The committee
has not only concentrated on Johannesburg's
municipal problems, but has resolved to
form a national  coordinating committee to
deal with noise in all municipal  areas as
well .

In addition, there is a call for a multi-
disciplinary approach to a I  I forms of
pollution,  in which cooperation and
coordination of various pollution
organizations are the keynotes.

Ekistics, or the science of human
settlements, must be an integral  part of
architecture.  As far as this relates to
noise abatement, consideration must be
made for factors affecting outdoor urban
noise, such as spacing between buildings,
as well as silence within the buildings
themselves.

Other ekistical  schemes include creating
areas of the city which are relatively
free from motor traffic at certain times of
the day, designing quieter motor vehicles
and construction equipment,  and asking for
government grants to encourage program
development.

The cooperation of business interests is
essential.  In addition, an emphasis must
be put on the individual citizen's role in
noise abatement by being quiet, cooperative,
and considerate.

The noise pollution problem has been recognized
by the parent organizations of the neighborhood
schools and they  in turn have sent expressions
of their  feelings to the  local school board,
city, state, and Federal governmental bodies
in this regard.

The following suggestions are made in
reference to any proposed standards:

1) Well established criteria include some means
of  limiting noise at any time, even for short
duration, to 85 dBA minimum.  Energy averaging
or similar  integration procedures probably do
tend to predict hearing damage, but they do not
define annoyance, nuisance, or other subject
effects.
                                                        108

-------
                                                                                                         07-007
                                           PLANNING & SITING
2) It is simple to measure noise levels in dBA
with simple, low cost equipment, which can be
operated by competent law enforcement
personnel;  or to automate such measurement
quite simply.

3) It is simple to forecast noise exposures on
the ground  whenever airport configuration and
aircraft type and operational  procedures are
known.  Thus, it is possible,  without any
measurement procedure at all,  to establish the
operating parameters of aircraft, the airport
layout (especially runway direction and
orientation), and to determine zoning areas
near the airport in advance.

This would  tend to preclude the need for much
of the proposed complex measuring procedure;
and it would go a long way toward avoiding the
nuisance of noise.
A reduction in speed from /O mph to 50 mph
would reduce the sound level by about 4 dBA.
The economics of doing this for long-distance
rural motorways could be investigated but
would undoubtedly be unpopular, even if shown
to be econom i c.

Urban main roads include commuter, bus and
commercial routes.   In general, both flows and
speeds are moderate, but the noise is increased
by the starting and stopping at traffic signals,
rotaries, pedestrian crossings and other
interruptions.  Distance is not available as
an alleviator and in many circumstances
barriers would be unacceptable.  Alleviation
from noise must therefore be sought by
reducing the flow as far as possible and by
smoothing it out to achieve moderate but steady
speeds, by the use of clearways, over and
underpasses, etc.   In these respects the
means of noise reduction seem quite compatible
with other aspects of traffic engineering.
07-007

Burt, M. E.

Road Research Lab., Crowthorne /England/

ASPECTS OF TRAFFIC DESIGN AND TRAFFIC
MANAGEMENT

Journal of Sound and vibration

Vol  15 No  1:23-24, 1971
This discussion  is centered on three types of
road: 1) through motorways: 2) urban main
roads: 3) residential roads.  In general,
noise increases with the traffic flow, with
the steady speed, and with the degree of hill
climbing and acceleration.  All  three are
clearly correlated with the type of road
concerned.

For through motorways, a reduction of 10 dBA
in the average sound  level would require a
reduction in flow from 10,000 to 1,000
vehicles/hr.  For a flow of 10,000 vehicles/hr,
a six-lane road would have to be replaced by
ten 3-lane roads operating near their maximum
economic flow.  The cost per vehicle/km would
be increased and the resulting nuisance from
the numerous smaller roads might well be
worse than that from the roadway itself.

In rural areas, noise is likely +o be a problem
only where the motorway passes near towns or
particular buildings.  In general, therefore,
distance can be used as an alleviator, possibly
aided by the use of trees in suitable areas.
In sensitive rural localities, and more
generally in urban areas, the policy clearly
seems to be to use motorways to their
capacity and to provide noise protection
by use of sound barriers or by environmental
planni ng.
An experiment  in area traffic control was
made  in which  80 signalized  Intersections  in
central Glasgow are brought  under computer
control.  Various control strategies are
being tested,  and results to date indicate
an improvement of 10-13%  in  journey  time? over
the pre-existing system, with a probable
reduction in noise.  No "before and  after"
noise measurements were made.

The provision  of noise barriers by means of
walls, embankments, or cuttings, raises a
number of problems.  If a roadway has a waI I
placed near the edge of the  shoulder, the wall
will  be struck occasionally  by vehicles, and to
avoid casualties it will have to have the
qualities of a good crash barrier or bridge
parapet.  It must present a  smooth surface
to the vehicle and must be strong and stiff
enough to deflect the vehicle back along trie
roadway so that the driver has some chance of
regaining control.  The ends should  be tapered
to avoid "gust" effects on cars caused by
s i de winds.

Roads in Britain are wet for about one-quarler
of the time, and skidding plays an important
part  in accidents.  At  low speeds the friction
between +he tire and the road surface is
affected by the material and the fine texture
of the surface, but as speeds increase a
rough surface  is required for adquate braking.
This tendency  \s unfortunately adverse as far
as noise is concerned.   "Grooving" the concrete
surface to improve skid resistance produced
high frequency noises in one test.
The Traffic Noise Index (TNI) is an advance in
that  it draws attention to the importance of
the range of noise levels in addition to the
upper and lower limits.  But as the  range to
be expected from a proposed  new road wiI I  no+
be known in  advance with any certainty,  and
indeed may well change with time, it may be
difficult to use the TNI as a design criterion.

Assuming that  in many cases  some reduction
in noise level  is desirable, the following
broad conclusions are reached.
                                                    109

-------
07-008
                                               PLANNING & SITING
     1) On mdjor through motorways reduction of
     traffic noise by control of traffic flow,
     speed or composition  is unlikely to be viable.
     It may be necessary to accept the generated
     noise and alleviate its effects by barriers
     or environment design.

     2) On urban main roads, carrying mixed traffic
     whore there is a conflict between transport
     and environmental considerations, some reduction
     in flow should be sought, and traffic management
     techniques used to encourage modest but steady
     traffic speeds.

     3) In residential and other areas where a quiet
     environment is the dominant consideration, it
     may be necessary to discourage through traffic
     and take measures against individual  noisy
     vehicles.

     4) ihe incorporation of noise barriers into the
     highway does not present serious engineering
     problems, but snow removal  problems are
     possib!e.

     5) Developments in road surfacings need
     investigation from the point of view of noise.
    07-008

    Kui fu, H. G.

    Minneapolis-S1.  Paul Metropolitan Airports
    Commission

    JET NOISE AND ITS IMPACT

    Airport Services Management

    Vol 12 No 10:16-18, 1971
    The evolution of the jet noise situation in
    the Minneapolis-St Paul area (Wold-Chamberlain
    Field) and the efforts of the Minneapolis-St.
    Paul Airports Commission (MAC) to deal with
    it are described.  Persistent and organized
    opposition to jet noise came in  1967-68,
    as exemplified by news stories   reflecting
    public concern.   In  1962, MAC established
    a Noise Abatement Committee, whose members
    included  representafives of the  FAA, airlines,
    the Air Transport Association, and the Airline
    Pilots Association.  Positive results  included
    the  introduction of  a  visual approach  slope
    indicator (VASI) with  the minimum approach
    slope angle  first set  at 2.7 degrees  (1966)
    and  later at 3 degrees, advisory signs on the
    runways reminding pilots of take-off procedures
    to minimize  noise, and new traffic patterns
    directing aircraft away from populated areas.

     In  response  to  increased public  concern the  MAC
    staff prepared a  comprehensive report  in  1967-
    68, which concluded  that a solution to the  local
noise problem was not possible until Federal
regulations limited the noise of the aircraft.
The MAC actively supported such legislation
in the following period, writing to each member
of the Minnesota Congressional delegation and
briefing two members of the Senate Aviation
Subcommittee on the noise problem faced by
the airport operator.

In 1968 MAC created the Metropolitan
Aircraft Sound Abatement Council (MASAC) to
provide continuous study of the problem and to
advise MAC.

A positive feature of Wold-Chamberlain  is that
cleared land at the end of instrument runways is
far  in excess of federal requirements (one mile
or more; the FAA requires 2,500 ft).  However,
volume of traffic at the airport has increased
from 1.4 million passengers  in  1956 to  4.3
million in 1967.  Use of terminal air space
will increase  10 times  in the next  30 years.


Retrofitting of the present generation of jet
aircraft is advised, because NASA studies
indicate that the cost of not retrofitting is
greater than the costs of retrofitting, if one
considers costs of alternative methods to
reduce noise around airports.  Alternate
methods include expensive land acquisition
contiguous to present airports and  reduction
of airport capacity.  The latter results in
increased operational costs to airlines
caused by delay in departing and arriving.
It is suggested that the aviation industry
and the general public share the cost of
retrofitting.  Moving airports to isolated
locations is not feasible because this method
defeats 1he goal of providing fast and
convenient transportation and also because
such airports only remain isolated for a very
short time.  New economic activities generated
by the airport attract people who soon begin
the crowd the airport boundaries.

There is presently worldwide opposition to
expansion of  airline facilities.  The noise
of the jet engine is used as a catalyst for
arousing anti-airport attitudes.  Without
quieting of the jet engine source, maximum
efforts by airport owners and operators will
not be enough to prevent strong community
reaction.
                                                        110

-------
                                                                                                         07-009
                                           PLANNING & SITING
07-009

Townend, D. S.

British Petroleum Co.,
London /England/

Britannic House, Moor Lane
London E.G.2

NOISE FROM PLANT AND EQUIPMENT—AN OIL
INDUSTRY APPROACH

Annals of Occupational Hygiene

Vol  14:101-107, 1971
The Oil Companies Materials Association (OCMA),
a British association of oil companies, has
developed specifications that will enable the
prediction of plant noise  levels, both within
the plant and also for noise emissions to the
community.  These specifications enable the
oil company to require builders and suppliers
of equipment for new plants to provide noise
data  in their bids in a standard, comparable
way.  They have been used  by British
Petroleum Co. for some time in draft form,
and Esso Petroleum has used similar
specifications for about 5 years.  The
specifications are:

NWG-1 Procedural specification for limitation
of noise in plant;
NWG-2  Noise limitation for individual items of
equi pment;
NWG-3  Guide to the setting of limits and use of
NWG-1 and NWG-2.

NWG-2 consists of the excerpts of NWG-1 of most
interest to suppliers bidding on petroleum plant
projects.  While manufacturers' representative
bodies often seek  limits set in dBA for
simplicity, OCMA felt that at  least octave band
data were needed for the effective design of
new plants.

Part 4 of NWG-1 contains a system for dividing
the entire plant area and environs into four
types of areas for the purpose of setting
Iimits:

G—general  work area limits
R—restricted exposure work area limits
S—speech and work interference limits
C— community area limits.


Part 5 gives standard forms for equipment
noise limits that can be used  by  the  plant
operator equally well  in the case of  user
designed plant  or contractor-designed  plant.
Part 2 of NWG-1  details  standard  noise
measurement procedures;  Part 3 gives  standard
calculation methods to be used.  These standard
calculation methods—one for large and one for
small  equipment—are  not scientifically precise
but experience  has shown that  they are
sufficiently accurate to meet  the demands of
plant situations.   For plant design work  and
for calculating the total effect of an array
of installations at a point distant from the
plant, the approach of Part 3 is to measure
sound pressure  levels around sources, convert
to sound power figures for each source, and
combine the individual power levels to get a
total power level that can be converted to
sound levels at distant points.  The
calculation method for predicting noise to
the community considers not only ground
absorption, but also two degrees of screening.

The plant operator must go through three
important steps for controlling noise.  First,
he must decide on limits for the four types of
areas mentioned.  In some countries limits
already imposed by authorities decide this
for him; otherwise he must decide for himself
on the basis of "good neighbor" and "good
employee relations" considerations.

Second, he must have a way to break down the
limits he has chosen  into limits for  individual
items of equipment that can be passed on to
suppliers and manufactures.

Third, he must have a standard for measuring
the actual noise performance of the completed
plant as compared with the specified  limits,
so that it may be objectively determined
whether guarantees by contractors or suppliers
have been met.  The OCMA Specifications give
the plant operator the tools to accomplish
steps two and three.

Insofar as guarantees are concerned, the
principle is that the user/operator takes
responsibility for remote area noise, while
the plant designer/contractor takes
responsibility for meeting limits within the
plant area.  This principle has also been seen
in operation in other industries, but not in
a forma Ii zed way.
07-010

Anderson, G. S.
GottemoeI lor, F.

Bolt, Beranek, and Newman, Inc.,
Cambridge, MA

URBAN HIGHWAY PLANNING FOR MINIMUM NOISE

At: American Association For the Advancement of
Science, Philadelphia, DEC 29, 1971

Cambridge, Bolt, Beranek, and Newman, 1971, 7p.
Noise control  through highway design is
discussed.

In Baltimore City a screening procedure has
been developed that combines the distance to
the projected  highway with estimates of future
                                                    111

-------
07-011
                                               PLANNING& SITING
     traffic  flow  and  speed  to  predict  a  new
     highway  noise level  - both  its  average  level
     and  its  degree of  fluctuation.  These
     predictions are then compared to noise design
     goals  derived from land  use and estimates of
     the  existing  noise.  Using this procedure, ten
     neighborhoods in  Baltimore have been spotlighted
     as potential  problems.

     Four case  studies  on Baltimore  neighborhoods
     are  discussed.  Highways were designed for
     noise  control  by  use of  earth berms, transparent
     acryllic shields,  and corrugated steel barrier
     waI Is.

     Noise  control  designs for  projected  highways
     in the North-Central and Northeast Corridors
     in the District of Columbia should reduce noise
     impact from 970 dwelling units  to  45; from
     325  dormitory rooms  to  zero; from  11 school
     buildings  to  zero; and  from 54  acres of  parkland
     to zero.

     Baltimore  City's  interstate noise  control
     should cost $3,500,000  - a  large figure, but
     only one-half of  one percent of the  total
     construction  cost.  For the District of
     Columbia,  the additional construction cost  is
     estimated  between  0.2 and  0.5 percent of the
     total  project cost,  for a  sum of $3,600,000
     if all sections of the  highway  network are
     constructed.   Funding  is available from  the
     federal  government for  well-designed noise
     barriers.  The problems  of esthetics are being
     overcome by the more imaginative designers
     who  have accepted  the chal lenge.   What  is
     primarily  needed  now is  a  broader  acceptance
     of these goals, and  a wider application  of the
     handbook methods.
conveyors when pipes are transferred, pipe
assembly lines, and boring machines.  They
produced more than 60-70 dBA at the eight
different measuring points alongside the
residential ares.

The factory studied three possibilities for
noise reduction:   1) suppression of the noise
sources (machines and conveyors);  2) building
a wall  between the factory boundary  line and
the highway (33.5 meters wide between the
factory and the residential  area); and 3)
building a noise barrier alongside the
residential area facing the highway and the
factory.  Because of economic factors and
probable hindrance of production,  the factory
abandoned all  of the possible plans.  Instead,
the factory finally came up with the idea of
building a warehouse, which was needed for
storage, and at the same time getting a noise
barri er.

The wall of the warehouse alongside the highway
was 5.6 meters high, and 6 meters from the
factory boundary  line.  The wall facing the
factory bui I ding was 8 meters wide and 11 meters
high so that fhe warehouse could act as a
barrier between the factory and the  residential
area.

After the  construction, the noise  level
conformed  with the environmental  standard set  by
Noise Abatement  Law of 55 dBA during the night
time.  Measurements before and  after the
construction show the amount of reduction
achi eved.
Measuring Place
   Before        After
Construction Construction
of Warehouse of Warehouse
     07-011

     Mugi kura, K.

     Kajima Construction Research  Institute /Japan/

     CASE STUDY OF REDUCTION OF FACTORY NOISE
     EMISSIONS

     Koojoo Sooon Koogai Taisaku Jitsurei

     Sangyoo  Koogai

     Vol  7 No 5:241-245
                                                                 Boundary Lines
                                                                   (1  and 21
 Resi dential
 Areas  (3  to  8)
       3
       4
       5
       6
       7
 Mean Values
                                                                                    63 - 73 dBA  57 - 59 dBA
                                                                                    62 - 71      52 - 55
   - 71
             53 - 58
64 - 69      53 - 56
64           53 - 57
65 - 72      53 - 57
71           53 - 57
65 - 72      53 - 57

65 - 72 dBA  54 - 57  dBA
     As an example of achieving  12 -  15 dB noise
     reduction at  little extra cost,  a warehouse
     was  built between  a residential  area and the
     factory.  The factory which manufactured pipe,
     was  140 meters  long; the  residential area was
     70 meters away.  The residents were mostly
     employed by the  factory.  Both employees and
     residents who were not employees complained,
     but  the  latter complained more.  Noise  sources
     were clankings between pipe and  the roller-
                                                          112

-------
                                                                                                              07-012
                                             PLANNING & SITING
 Bolt, Beranek,  and  Newman,  Inc.,
 Cambridge, MA
 Washington, Supt, of  Documents,  US6PO,
 SN 2300-1194,  1971, 20p.  70 cents
Paper-and-penci I  cak'ilat
presented  by  the  Dept.  of
Development  (!tUD)  for  eva
exposure oi  a  hoiis j ^r,  cjt
from aircraft,  nearby  roa
Designed a*:,  a  pre! irni nary
guidelines do  riot  const it
HUD  is encouraging their
be evaluated.   he site i
four  eategories.   Clearly
both indoors  on;i  outdoor"
(som'j  i o-. e  exn* :, ure,  ! u1
with common  building tech
pleasant outdoors),  Ncrma
(unusual and  cos"Iv  ionsr
sore i  idoor  quiet,  ,.nd  Oa
noi;>e  -ourv.e  and  site  no-
                            on methods  are
                            Housing and  Urban
                            uating the  noise
                           -_• 1o  intrudi ng noi so
                           ds and rai I reads.
                            sc1oening tool,  I he
                            . fe riUD pol icy,  but
                            .->e so that  they may
                             nIaced in  one  of
                            acceptable  (pleasant
                            .  'formally  Acceptable
                               • ,,', ah «  i ridoors
                            iques and reasonably
                            ly unacceptable
                            ue f i or _^ reeded  for
                            r K r ^ separating
                            ed outdoors), Clearly
                            ' ' ^n~ rr-eded  for
                            oxpens oj,  and
                            rolerabIe at  any
The ea'^jory  dot er r.ii r,-d >oi  norse  f rcrn the
worst so^r> e  is Jeemea the category  of the
site, e/  •-  tn^ueh the ~'~ o-sori e3 dictated by
noise f r ON  'iher  so jr v    a,  v Owre  tavorablo.

The calculation tor •   >. . at r noise  presupposes
the aval la1, i ' ir,  or •  '      e oois^  Rating (oTIR)
or Noise  exposure Fot  <, asi  (tCF) cornours for
the nearby  (15  rn'ie,  . i  less) airport,  but a
simple  method  is  prox'Jed 4o cor.oiruct
app rox i  ma t e feniojre  i i  <'. ^e a r, dp with CNR
or I-IEF  contours can u. bv  17  and
adding  llos to  the number  (jf dayTir:ie operations.
The resulting number  •   u^ed to lay ou1  the
30 and  40 UEF r--,nt^->jr;  jr,.,i,.id 4- - airport's
r u r i w a y s .
 I f  the s i +e is  i rs i -i;
 con!oui , i i  is  C'eur i
 between  the NEF 30  an
 Norma I I y Unaoceptc-D ! •;
 outside  both the NLL
 decision ahout  /.nethu
 Acceptab 'e or C'> •  > '
 close i t ; , to  i;,
                       •1-0 NIC F-40  (or  CNR-1 15)
                        , iirtCk' 'ptau le.   If  it  is
                        40 contour;,,  it  is
                         \*Hien "the s i f e lies
                       -  and 40 con tout s,  the
                        it is ,'Jorrna I ', y
                       ''. ceptabL, dc-pends  on  how
                        30 cr,,,tou.  .
For roadway noiS'",f  all  major roads within  1000
feet o* the  . iK~  -^r- considered separately,  and
the worst case       -!s the determination  of
the category.   !_••<. AM se,  separate evaluations
                                                              are tiade of  noise fret;1 autoriiobi les  and  from
                                                              trucks  *or tach  roadway, and The worst  case i .-
                                                              cent r c i I i r,q.   ro>  automobile nr_ise   4"e datr.
                                                              required are 1)  the effective  distance  of rni
                                                              road from  *he iite (a function ct  1 he  distartt
                                                              from, the s] *e to the center lines ot  the noaicj
                                                              lane and  In  farthest lane;  th' effective
                                                              Distance i - oj off of a nomo/.!'!'   /'   ' Lo roa*
                                                              hourly  *loi,  o*  tratf-c (vot''
                                                              directions combined/.  Ir   trio  ^iiipic^.  co L-
                                                              which assumes a  mean vehicle speed  of  60 mph,
                                                              these numbers are plotted  on a araph  end The
                                                              category ct  the  sr'o is '^ao t  i •' direct!-,.
                                                              However, for o^he'  sreeds, -:nti f^ir  r*- -  ' a^ '
                                                              like the existence z' shie'-'i'ir tarro.1
                                                              stop-and-go  tral.ic, appropri-j.  ad    f
                                                              made to ~rne  vehM c les-per-hour  riuriber  betv,r'
                                                              is plotted on tne araph.   (No  CxO,"rectiOn fo~
                                                              night-tir.e HI;H :e is offer?'!.)
if 1he nrad:ent is more than j% this  fa  t  rru^r
be taken  into  ac^o.nt.   If  fne giauiert  i'.  ft,re
than (}%,  tre ei'.-c+  o4  the cr>l c .i I,,'. io' Piefhod is
to double  the  ..I'octive, i. uc f.i-[ si-ho  i  nu,''n, r
actually  LiS'-d  "io plot the nc i so r'i'fec

The calculation ^   positive stti,o'j   i _>,  j. ,
shielding  barriers (either ..utlings or fer;ce;
and learns)  i ,  r ?(]uired  only when the  noise
effect  is  j  Poroe' i  rie  case L -,!.-erir'  to
categories.   i\, Take an adju *ner.t  i O' shielding
' > a r r i c i s ,  f h >-   n, > u t  v] a t a ' f  ,' 11 • •_ a   > .

     distane  he r vscun The .•..,"< i    i   . ..  r.-,r,.:
        and  the Darner,
     distni";e  oetween the s tc .r u  -f--,c   ,;r , l( ,
     ._, lev -I t i ,'  o f  the, • i aow iy
     olevar , -,.  o:  the _ • Te
     elevoiio.   '-i  ihe i'-,p  ct the barn
     hoi 4h t  of  :i,e bu, ! i'i', • f  - e  err  ••  d
        the  si;e.

A  s i n; ';''•"!     ,  ''---,  mot hod,  J:  ' o
interrelated sets  of families of cai y^s  oi1
laid out en  one work sheet,  is provided  to  aid
in the acttal  -r rmuf a f io"
                                                               ra i li.ay has more  than  10  "i
                                                               (10  fir, -7 am) .  Tor  les;  -ii
                                                               distances t ron  the  rai lre,a'
                                                               adjusted before tne  4i!,ilc i
                                                              A final 0,11 i on,si  eve! uat ior ,
                                                              Test,   i -  j   .-!•;.!.,  ,\.   i ><-  i',_ i
                                                              tlit. to1 a i  Ticis^  level  fr.jri'  all
                                                              the use or ' "n  s  pre,suro  l-,v
                                                              oth^r" -',^iprnci *,  no  relafi.
                                                              accepfan i  lit/  I]T  ^  ruousing  si i
                                                              the mea >urerner't.  One  mian  hoic^. readii'i
                                                              material  ,/i rh  A/hioh, f,c,th  aro  f.imi liar  in  sucti
                                                              a wav ab noi  t -  hhaoK  ;',e  ,,CM  Between himself
                                                              and the other Man.  The other" man  backs slowly
                                                              away as the first man  reads aloud,  riot raising
                                                              his voice  MI an attempt to  main t.. in
                                                              comrnunicat on.  'At  the pcin'  wneit,  Ts'e I 'Stener
                                                              can only  understand a iCut'e,  •'-_ i-oro or I  ao
                                                       113

-------
07-013
                                               PLANNING& SITING
    over a period of 10 seconds or more, he stops.
    The distance between the two men is measured.
    Several trials are taken, with the men
    changing roles, and the results are averaged.
    If the test  is performed on the site during
    peak noise periods (e.g., during traffic
    rush hours) and also at times when the noise
    is likely to be least annoying (e.g.,  between
    10 pm and midnight),  then the averaged
    distances for the worst trial period may be
    used to evaluate acceptability:
        Distance Where
        Understanding
        Becomes Very
          Difficult

        More than 70 ft
        26 - 70 ft
         7 - 25 ft
        Less than 7 ft
Acceptabi Iity
   Category
Clearly Acceptable
Normally Acceptable
Normally Unacceptable
Clearly Unacceptable
    07-013

    Lane, S.  P.

    California Univ.,  Los Angeles

    School of Architecture  and Urban Planning,
    Zip  90024

    AUTOMOBILE AND TRUCK TRAFFIC NOISE  INTRUSION

     In:   Lane, S., Freeway  and Highway  Noises:
    An  Information Base for Urban Development
    Decisions

    Springfield,  VA, NTIS,  PB 202434,  1971, 90p.,
     (p.  8-42) HC:$3.00 MF:95 cents
     A  study  designed  to estimate  residential
     interior noise  levels  in  Los  Angeles houses
     near freeways  is  presented.   In order  to
     determine truck noise  and  automobile noise as
     a  function of  distance from the freeway,
     generalizations were made  from data from  four
     studies  in the  Los Angeles area and one from
     Detroit.   Because the  reporting formats varied,
     adjustments and approximations had to  be  made.
     The reference  point for distance  was chosen to
     be the cenrer  line of  near traffic flow.
     Measurements made from other  reference points
     were adjusted.

     The assumption, substantiated by  a separate
     Michigan sfudy, was made that peak noise  levels
     correlafed with truck  traffic and the  average
     of the continuous noise level correlated  with
     automobile traffic.  A composite  of various
     noise levels as a function of distance from the
     freeway follows.
     Type of
     Source
                 Sound Path
Distance (from center
Iine of near traffic
      flow)
100ft  200ft  500ft
Steady flow Unobstructed 75dBA  70dBA  68dBA
traffic
(2000-4000
per hour
in the      Obstructed   62     57     53
near-side
lanes),
avg. sound
level

Freeway truck
traffic,    Unobstructed 82     75     68
typical peak
sound  levels
(one peak
per truck)

These composites were then used in the
estimation of noise intrusion into the
residential areas.
                                  The outdoor background noise (without nearby
                                  traffic) was taken to be an average of 50 dBA.
                                  Measured background  levels for other U.S.
                                  communities were taken into account, as well as
                                  the following data from  Inglewood,  in the
                                  Los Angeles area:
                                  Location
                                                       Time  Range,dBA  Ave.,dBA
Middle of residential Day  42-56      48
area
Periphery of area     Day  52-58      55
Residential area
adjacent to main
roads                 5 am            37
Residential area      4 pm            58

Although adequate theories for noise reduction
of assembled buildings are still in the
formative stages, a review of observations made
in several U.S. cities indicated that,  in
general, the average noise reduction for traffic
noise of residential buildings  is  10 dB with
windows open and 23 dB with windows closed.

In Los Angeles, residential unit lots start at
least 100 feet from the center of  the near
lanes.  There are about three blocks within
1000 feet (or 1/5 mile) of a freeway.   Since
the average outdoor background noise  level  in
a quiet neighborhood is about 50 dBA, the
interior noise level (windows closed) will be
about 30 dBA.  Combining all  the variables, it
was estimated that one block from  a freeway,
auto and truck noise will cause  intrusion  levels
of 15-25 dBA.  Three blocks from the freeway,
intrusion  levels are still greater than 10 dBA.
These estimales apply when the sound path  is
unobstructed, e.g., houses located on a street
perpendicular to the freeway.

When the sound path  is obstructed  (e.g., houses
in the middle of a block on a street parallel
to the freeway), estimated intrusion  levels are
about 6 dB  loss than those given above.

With windows open, the interior background
noise is about 40 dBA  (50  dBA outdoor
background noise  level minus 10 dBA noise
reduction of the residential building).  Again,
                                                         114

-------
                                                                                                         07-014
                                           PLANNING & SITING
intruding freeway noise can cause noise levels
10 dBA above background interior levels within
three or four blocks of the freeway,  and greater
than 20 dBA within one block.

The estimates are probably conservative.
Although there were few actual  measurements
to compare with the estimates,  observed
noise level contours obtained  in one
residential area were plotted  against the
computed contours because of differences
in attenuation in various sound paths.  In
this case, actual observed noise levels were
significantly higher than was  expected, perhaps
because of above-average volume of truck
traffic and underestimation of  noise  on nearby
surface streets.
designs that utilize higher temperature
insulation and smaller,  unidirectional  fans.
When fan noise is the problem,  external
treatment is effective.   AcousticaI Iy-lined
fan covers and enclosures are used for
noise control.

Control valves are responsible for nearly all
the noise generally blamed on piping systems.
Valve noise often persists for long distances
For noise control, there are valves with
special  low-noise internal design, or inline
silencers.  Valve designs which limit the
internal velocity to substantially less than
sonic are most effective.  Acoustic lagging
is the  least effective noise control  because
of the downstream propagation of valve noise.
07-014

Seebold, J. G.

Standard Oil Co. of California,
San Francisco, CA

NOISE CONTROL  IN OUTDOOR PROCESS PLANTS,
GENERAL DESIGN CONSIDERATIONS AND SPECIAL
PROBLEMS

In: Crocker, M., Proceedings of the Purdue
Noise Control Conference, JUL 14-16, 1971

Lafayette, Purdue Univ., 1972, 594p.
(p. 163-168)
Corrective measures taken in a noisy plant
after startup are more costly and  less effective
than proper design of original plant equipment
as  long as you know what to do at the design
stage.

The remote effect of an outdoor plant depends
on the nature of outdoor sound transmission.
The designer has little control  over this
problem.  However, the designer can deal, to
some extent, with the sound power generated
within the plant.

Intense noise accompanies the high rates of
heat release inside process plant furnaces.
There is a general  agreement that combustion
roar is the most serious problem.  Combustion
roar,  inherent in today's burners, has to be
confined to the firebox.  Other design
alternatives for noise suppression lack
practicality, effectiveness, or both.

Fan noise is produced by turbulence created
by blade passage through air.   Except for
motor fans,  external  acoustic treatment is
rarely practical.  Designs that  minimize
turbulence are used for noise control.  Fans
are usually  the major source of  noise in
air-cooled motors.   In large motors
electro-mechanical  noise may become important.
Some relief  from fan noise can be obtained from
Like valves, compressors produce noise of high
intensity in a frequency range which spreads
easily in the connected pipework.  Inlet
and outlet silencers may provide sufficient
noise reduction without total  enclosure.
Further technological development is needed
here.

In many piping systems, noise can build up
in the fluid or more can escape through the
pipe, or both, and probably explains why a
normally unimportant noise source is
occasionally found to be a real troublemaker.

Recent studies suggest that for high speed
compressors and valves in gas service, most
of the energy wi I I  remain in the gas, and
inline silencers are most effective.  For
pumps and valves in  liquid service,   it appears
that most of the energy is transferred to the
pipe, suggesting that vibration isolation
should be most effective.  Flares used to burn
excess process gases can be sources  of
community annoyance.  In the simple  steam
jet, the major source of noise is the highly
sheared mixing zone just downstream  of the
nozzle.  Combustion noise and light  are the
major problems in  elevated flares.   Flare noise
can be reduced to some extent by using multiport
steam nozzles.  The quicker the steam becomes
thoroughly mixed with the inspi rated air, the
less the noise produced.

To be successful  today, specifications should
set forth specific minimum design features for
noi se control .

A process plant should be viewed as  a noise
producing system.   Many sources contribute to
the composite noise  levels.  For each source,
some noise reduction can usually be  had by
several different means, each having its
own effectiveness and cost.  This suggests
that a system approach needs to be taken to
       ' "ist-cost designs.
Where design solutions are available,
corrective measures taken in a noisy plant
after startup are more costly and less
effective than proper design of original
p lant equi pment.
                                                    115

-------
07-015
                                               PLANNING & SITING
    07-015

    Matheson, W. K.

    Wold-Chamberlain Field,
    Minneapolis-St. Paul, MN

    OPERATIONAL PROCEDURES

    Airport Services Management

    Vol  12 No 10:19-20, 1971
    Operational procedures already carried out at
    Wold-Chamberlain Field (Mi nneapol i s-St. Paul)
    that have  reduced aircraft noise include
    reduction  of training flights, installation
    of more electronic navigational aids, take-off
    signs, and partial  nighttime curfew.  Further
    measures under consideration are extension of
    the curfew to charter aircraft and the
    introduction of special  ground run-up areas.

    Northwest  Orient Airlines and North Central
    Airlines,  both of which  use Wold-Chamberlain
    as home base, have cooperated in removing all
    training flights except the minimum required
    by FAA for pilot certification.  Other training
    flights use less noise-sensitive airports.

    Large yellow and black noise abatement signs
    installed  at the take-off end of five runways
    request pilot's cooperation; signs  also serve
    as a visible reminder to passengers of the
    airport's effort to reduce noise.

    Aircraft approaching the airport on the back
    course I LS fly over noise-sensitive areas.
    The installation of glide slope and marker
    beacons on the back course ILS, the first of
    its kind in the US, has  furnished the pilot
    the electronic guidance  needed to follow a
    3-degree descent slope,  insuring higher
    approach altitudes than  before.

    After a public hearing  in  1970 showed that
    night operations were the primary  reason  for
    complaints, scheduled carriers voluntarily
    agreed to  limit night flights  in the
    11 pm-6 am period.

    Further noise abatement measures are  under
    consideration.  The  night  curfew does not
    now apply  to charter aircraft, which  may
     legally  refuse to  accept  a noise-preferential
    runway and instead take off  at night  over
    heavily populated  areas.  A  proposed  field
    rule would apply night curfew  rules to
    charter ai rcraft.
     A  second  proposed  measure  is the  desi
     o1  a  specific  it-cund  run-up area  chosen  m
     , i 1 1 i-ii  rj   ^'    j 
-------
                                                                                                         07-017
                                          PLANNING & SITING
suggest that in busy urban areas 50 dBA by day
and 35 dBA by night should not be exceeded for
more than 10% of the t i me i ns i de dwe iIings.
Methods of achieving these standards for
existing buildings near motorways may  range
from providing openable double windows  for
bedrooms only, to sealed double windows for
both bedrooms and living rooms.

The Greater London Council is urging the
Government  to recognize for grant purposes
unavoidable expenditure in dealing with the
noise factor and with daylighting and  amenity
problems when new motorways  are introduced
into 'quiet' urban areas.1

Before motorway M.1  was opened into the
northern suburbs in 1967,  a  survey in  the
residential  Mill Hill  and Hendon areas  was
carried out to establ ish existing noise
levels.  Measurements were repeated on  the
same day of the week and at  the same time.
The main conclusions found were that the
biggest increase in noise levels due to the
motorway occurred at night,  up to 14 dBA.  In
the case of houses whose back gardens  were
3-4 meters above the motorway,  the noise  levels
dropped rapidly from the back fence to the back
wall of the house, which shows  the effectiveness
of route selection combined  with taking
advantage of ground contours.

At Heston, M. 4, at a height of 2-4 meters,
passes only 16 meters from typical three-
bedroom semidetached houses.  As a noise
abatement procedure, the simple wooden  fences
now standing will be replaced by a purpose-built
noise barrier 2.5 meters high and consisting
of a double skin of plastic  with an overall
surface density of 12 kg per sq.  m.

On the two shorter lengths of motorways  within
London, the A.102CM) and A.4CKM), measurements
were also made before and after the opening
of the roads.  The most striking results were
found in Tunnel  Avenue and Westcombe Hill,
two roads parallel  to the A.102(M).   When the
motorway was opened, noise levels at the front
of the houses,  which faced away from the
motorway, dropped by about 5 dBA (daytime) and
rose by about 5.6 dBA at the rear.

In the case of the A.4CKM),  measurements are
not complete.  However,  in several previously
quiet roads  consisting of  older 3-4 storey
houses, noise levels of  up to 80 dBA were
recorded by  day outside  windows.
07-017

Zeller, W.
Siepmann, J.

Institut Fuer Schall-und Waermeschutz,
Essen /West Germany/

Krekelerweg 48

NOISE PROTECTION IN A LARGE REFRIGERATION
PLANT LOCATED IN A RESIDENTIAL AREA

Laerm-Immi ss ionschutz bei Einer Groesseren
Kaelteanlage  im Wohngebiet

Lae rmbekaemp fu ng

No 2/3:33-35,  1970
The City Hospital  in Essen, Germany had to
expand its refrigeration plant to provide
ai r condition i ng.

The neighboring residences were located only
30 meters away in  a totally residential area,
where the noise level  could not exceed 35 dBA
during the night.   Therefore special  sound
protection measures had to be used in order
to comply with the prescribed standards.

After two prospective cooler sites (A&B)  were
established, considerable measurements were
taken at 6 measuring points in order to
determine the noise levels and thereby the
appropriate  location.   The noise levels at
cooling tower A at a thirteen (13) meter
distance reached 65 dBA when in full  operation.
The background noise there reached 57 dBA.
The Cooling Tower  location B showed noise
levels of 63 dBA at a 13 meter distance.

Therefore the noise level had to be reduced
by about 30 dBA by means of damping devices.

Absorbant materials staggered in baffle boxes
on the ducts were  chosen.  After these devices
were installed, measurements were taken between
midnight and 1  o'clock at night at the nearest
home, with the following results:
Number of
Coolers in
use
Noise Levels
Fu I I  Power
(dBA)
Ha I f Power
(dBA)
                                                                             46
                                                                             44
                                   42
                                   42
                                   41
                                                    117

-------
07-018
                                               PLANNING & SITING
     07-018

     Sadowski, J.

     Instytut Techniki Budowlane, Warsaw /Poland/

     Ul. Wawelska  2

     TRAFFIC NOISE IN WARSAW, GDANSK AND POZNAN

     Untersuchungen Ueber den Verkehrslaerm  in
     Warschaw, Danzig and Posen

     Lae rmbekaemp fung

     No 3:65-69, 1969
     In  1966 the  Institute for Building Technique
     (ITS)  in Warsaw conducted its first survey on
     traffic noise  in Warsaw.  Later the cities of
     Gdansk and Poznan were  included.

     As  a  result, uniform measurement and noise
     maps  and a catalogue with the acoustical
     characteristics of various city planning
     elements were  prepared.  These were later
     used  as a basis for aviation, city, traffic,
     and  railway  noise measurement  investigations.
     Measurements were taken  in;
     1)  Warsaw at  1500 measuring  points and  included
     aviation, railway, truck and street car noise,
     2)  Gdansk at 500 measuring points  (railways,
     truck and street car noise),
     3)  Poznan at  100 measuring points  (truck and
     street car noise).

     The heaviest traffic intensity was between
     1-5 pen, with hardly any variations between the
     time  span, whether 20 or 240 minutes.  During
     that  time the  traffic noise  level  reached
     above 90 dBA  in the heart of Warsaw.

     The surveys  and noise maps have produced
     valuable material for future projects and
     further city planning.
Growing airport development and advancing
aircraft technology have not only resulted in
higher noise levels,  but in public awareness
as well.  As a result,  ordinances regulating
aircraft noise have been passed.  Noise
regulations are now in  effect at London's
Heathrow Airport, and in New York.  A critical
look at these ordinances is presented.

The State of California has proposed the most
complex regulations against aircraft noise
to date.  The two-fold  purpose of their
regulations is:  1) to  bring about cooperation
between airport personnel  and the community,
and 2) to impose penalties on aircraft
operators exceeding set noise limits.  The
proposed regulations  are based on perceived
acceptable noise limits of the communities
surrounding the airports and the economic
and technical  feasibility  of complying with
the standards.  The regulations contain eight
separate airport classifications based on
traffic density and aircraft type.  Maximum
single event noise exposure levels are
established for each  type  and measured as
the noise exposure level for a single event
with a duration of 10 seconds.  Any aircraft
exceeding specified limits would be committing
a misdemeanor and the operator could be
subjected to a $1,000 fine.  To maintain
these standards, elaborate noise monitoring
equipment will have to  be  used 24 hours a day.
The airport operator is responsible for the
monitoring and maintaining records, county
inspectors to review the records.

Economic questions arise.   Typical installation
at Los Angeles International Airport will
initially cost $200,000 to $250,000 to
monitor 4 run/jays on  a  24-hour basis at
30 points surrounding the  airport.   Installation,
operation and maintenance  will cost about
$1,000,000 for the first year.

Older jet aircraft will have to be retrofitted
with noise attenuation  kits to meet regulations.
It will not be feasible to enforce regulations
untiI  then.

Although unduly complex and very costly,  it
is felt that the proposed  regulations wiI I
accomplish a much needed reducfion of noise
levels  in and around U. S. airports.
     08-001

     Schneider,  M.

     California  State Dept.  of  Public Health,
     Los AngeIes

     Bureau  of  Occupational  Health  & Environmental
     Epidemiology
     P.  0.  Box  30327, Terminal  Annex

     A CRITICAL  LOOK AT AN AIRPORT  CONTROL  ORDINANCE

     American Industrial  Hygiene  Association  Journal

     Vol  32  No  7:480-487,  1971
08-002

THE FIRST TRUCK RESTRICTION ON FEDERAL
HIGHWAYS DURING NIGHTTIME

Erstes  Lastkraftwagen Fahrverbot  auf
Bundesstrassen fuer die Nachtzeit

Kampf dem Laerm

Vol 18  No 6:166,  1971
                                                         118

-------
                                       LEGISLATION & STANDARDS
                                                                                                         08-003
The first truck restriction on Federal highways
was passed in Hessen, Germany.  The law passed
in Hessen pertains to Highway 354 between
Alsfeld and Homberg  in North Hessen for
night-time between 10 P.M. and 6 A.M., and
restricts the passage of trucks over 4 tons.

Minister Karry explained that all attempts
must be made to restore peace at night to
citizens living near Federal highways.  It
is unfortunate that  the restriction does
not apply to other main routes  in Hessen as
well.  Consideration was given to the
citizens instead of  to the freight  industry
in this case because a parallel route was
available that could be used by trucks instead
of Highway 354.
08-003

Goldstein, S. N.

Mitre Corp., Mclean, VA

A PROTOTYPE STANDARD AND  INDEX FOR
ENVIRONMENTAL NOISE QUALITY

At: The Eighty-Second Meeting of the Acoustical
Society of America, Denver, OCT 21, 1971

McLean, VA, Mitre Corp, 1971, 11p.

Author
A prototype technical standard for environmental
noise  is proposed  in terms enabling an index of
noise quality to be defined and calculated.  The
standard takes into account the damaging
aspects of chronic exposure to loud noise as
well as psychologically disturbing aspects of
typical community  noises which are not loud
enough to be physically dangerous.  Inasmuch
as the standard is intended to portray
environmental  quality rather than to reflect
damage risk criteria, it is generally
conservative with  respect to work-related
noise standards,  such as those specified by
the Walsh-Healey  Act.  The basic standard
specifies a distribution of noise intensities
to which an individual  might be exposed in
a 24 hour period.   The distribution may be
approximated by the composite of three
Gaussian distributions with means and
standards deviations of (30 and 3), (50 and
8.5), and (70 and  14) dBA.   These component
distributions correspond to 8 hour periods
for sleep,  miscellaneous daily activities, and
work, respectively.  Alternative strategies for
obtaining data for calculating the related
noise quality  indices are discussed.
08-004

Denisov E. I.

Institut Gigiyeny Truda i  Profzabolevaniy
AMN SSSR, Moscow

NEW HEALTH NORMS ON NOISE

Novyye Sanitarniye Normy po Shumu

Gigiyena Truda i  ProfessionaI'nyye Zabolevaniya

Vol 14 No 5:47, 1970
"Health norms and regulations on noise
abatement in areas and rooms of industrial
enterprises," No. 785-69, promulgated by the
Ministry of Health of the Soviet Union on April
30, 1969, was elaborated by the Laboratory for
Noise and Vibration of the Institute of
Labor Hygiene and Occupational  Diseases.  The
norms and regulations were based on in-house
documents and international recommendations.
The document establishes permissible noise
levels, conditions and specifications for
measuring it, basic measures for noise
abatement and for prevention of harmful
effects.

The norms regulate the maximum permissible
spectra of noise using the family of criteria
curves recommended by the TK-43 Committee on
Acoustics of the ISO.  Rooms used for
intellectual work (offices, design bureaus,
etc.) have a maximum permissible noise  limit
equivalent to about 50 dBA; rooms for office
work (typing pools, rooms with office
calculators, etc.), 60 dBA; control consoles
and observation rooms, 65 dBA;  laboratories
with noise sources, 75 dBA; and work areas in
rooms and areas of industrial enterprises,
85 dBA.  The norms allow for corrections for
duration of the noise during the work shift
and for the character of the noise (a correction
of 5 dB is allowed for tonal  or impulse noise
measureable by a standard noise level  meter).

The norms also indicate measures for technical
and medical prevention of adverse effects of
noise.  They require periodic medical
observations of persons working under noise
conditions beyond the permissible  levels
and give contraindications to employing persons
in noisy shops.  These are based on domestic
research on the effects of noise not only on
the auditory organs, but on the organism as
a whole.  The norms allow for elaboration of
departmental norms on noise, with subsequent
promulgation by the Ministry of Health of the
Soviet Union and by the State Construction
Agency of the Soviet Union (Gosstroy SSSR).
These are to be based on ergonomic requirements
and not solely on established maximum
permissible levels of noise.
                                                    119

-------
08-005
                                           LEGISLATIONS STANDARDS
     08-005

     Lesser, J.

     Port of New York Authority, NY

     THE AIRCRAFT NOISE PROBLEM:  FEDERAL
     POWER BUT LOCAL LI ABI LITY—PART I

     The Municipal Attorney

     Vol 13 No 1:13-21, 1972
     It  is  largely because of aircraft noise that
     new desperately needed airports cannot be
     developed and existing air terminals cannot
     be expanded.

     Since  1815, courts have been deciding questions
     of who owns the air above property.  The first
     Supreme Court decision on aircraft noise came
     in  1946, in the case of United States v. Causby.
     The court found in favor of Causby, ruling that
     the low aircraft altitudes caused trespass and
     nuisance.  The owner and operator of the
     aircraft was held  liable; the case did not
     involve possible liability of the airport
     operator.

     In  1952  local government attempted its first
     regulatory role in the field of air traffic
     control.  The Village of Cedarhurst, NY, near
     Kennedy  International  Airport, enacted an
     ordinance forbidding aircraft flyovers at less
     than 1,000 feet altitude.  The Airline
     Association and Port of New York Authority
     brought suit in Federal Court to enjoin
     enforcement and were upheld.  A similar
     ruling was made in New Jersey in 1954.
     Three  1958 Court of Claims decisions, all
     on cases modeled after Causby, awarded
     compensation for de facto taking of
     easements.  Since each suit dealt with
     military aircraft,  the government was held
     liable as owner and operator.
    08-006

    Lesser, J.

    Port of New York Authority, NY

    THE AIRCRAFT NOISE PROBLEM:  FEDERAL POWER
    BUT LOCAL LIABILITY—PART  II

    The Municipal Attorney

    Vol 13 No 2:30-39, 1972
    The  impact of the Supreme Court decision
    rendered  in the Griggs  litigation against
    the  operators and users of the Greater
    Pittsburgh Airport  is discussed.  This  1953
litigation was a test case.  The Board of
Viewers awarded $12,690 to Griggs for the
condemnation of his property as of the day
in 1952 when "he Pittsburgh Greater Airport
opened.

Federal court:; have held that before a property
can be condemned aircraft must physically invade
the landowner's airspace.  On the contrary, some
state courts have ruled that lateral flights
can constitute compensable takings within the
meaning of constitutional standards.  The
burden of proof that property has been
constitutionally appropriated is in dispute,
as well as the statute of  limitations.

The effect of the Griggs ruling was to direct
property owners to sue the airport operator
in an inverse condemnation action, thus
placing the f'nancial burden on the segment
of the aviation community  least able to do
anything about it.   In a recent inverse
condemnation action  involving over  1,500
plaintiffs owning 750 separate residential
properties in the vicinity of Los Angeles
International Airport, total damages of
$750,000 were awarded.  Similar awards have
been made in other states.

Local  ordinances have generally been defeated,
but have prompted regulatory action by airport
authorities.  Zoning  laws by themselves have
not been much help in fighting aircraft noise,
because when they limit the use of property of
existing owners, they constitute a taking of
private property without compensation.

The 1968 Federal   legislation on aircraft
noise requires the FAA not only to prescribe
standards for measuring noise,  but also issue
rules for its control and abatement.  In
1969 the FAA's standards for noise took effect.
Unfortunately, the noise standards were not
as strict as airport neighbors and airport
operators had hoped, since the FAA had previously
stated that noise levels of 106 EPNdB measured
at three statute miles from the start of
take-off roll, one statute mile from the landing
threshold, and 1,500 feet from fhe center line
of the runway were 'well within the state of
the art.1   Yet, the FAA's rule would permit
noise levels on very heavy future aircraft to
reach 108 EPNdB at measuring points farther
from the runway than originally proposed and
contains a "trade-off" provision which would
mean that noise levels as high as 110 EPNdB
would be permissible.  Since the EPNdB scale
is constructed on logarithmic base, the
difference between 106 and 110 EPNdB alone
would reflect about a 50 percent increase
in annoyance.  The "trade-off provision
would allow noisier take-offs and landings,
for instance, if they were compensated for
by a reduction in sidel ine noise.   In addition,
the rule was further diluted by exempting the
initial group of approximately 160 Boeing
747's, the jumbo jets,  from its coverage.
However, the FAA makes no claim that the rules
are acceptable or unacceptable for particular
a Irports.
                                                        120

-------
                                                                                                         08-007
                                       LEGISLATION & STANDARDS
08-007

Hurlburt, R. L.

Inglewood Department of Environmental
Standards, CA

105 East Queen St, Zip 90301

NOISE REDUCTION DESIGN SPECIFICATIONS  FOR A
SOUNDPROOFING ORDINANCE FOR SINGLE AND
MULTIPLE FAMILY DWELLINGS

In: Inglewood's Community Review Program:
Final  Report

Inglewood, CA, City of Inglewood,  1972
(p. 64-68)
The City of Inglewood proposed a special
residential sound proofing ordinance because
of Inglewood's particularly high exposure to
aircraft noise from Los Angeles International
Airport and aircraft operations associated
with it.  However, the ordinance is not
applicable to communities generally or even
to those impacted by aircraft noise, without
further study of the particular local
conditions.  These conditions include housing
practices  in the area and the particular
aircraft noise environment.

The zones and design criteria envisage a two
stage reduction of noise  levels inside single
and multiple family dwellings.  They  were
developed primarily from the results of
soundproofing programs in a  localized area
around the airport.  For the Inglewood area,
residential areas outside the 65 CNEL contour
need only normal housing construction to
provide an acceptable noise environment
i ndoors.

Areas in the 65-75 CNEL range require that the
building construction provide a reduction of
28 dBA, and those  inside the 75 CNEL contour
need a 35 dBA reduction, which appears the
practical  limit without detailed soundproofing
studies and designs in each new construction
at extreme increases  in cost.  Zones in the
soundproofing ordinance bounded by the 65 and
75 CNEL contours seem the best choice for
specifying two stages of soundproofing, with
the goal of providing uniform indoor noise
environments for all the dwellings in  Inglewood.
These zones are to be selected not on present
CNEL contours, but rather on those estimated
for the year 1980.

New housing (and additions costing more than
$10,000) in the 65-75 CNEL contour interval
must provide at least 28 dBA noise reduction
with all  external  doors and windows closed,
according to the proposed ordinance,  which
specifically requires certain construction
features.  These features include an air
conditioning system, interior fiberglass
linings in air ducts,  solid core external
doors,  special  workmanship on external  doors
and windows, and well-fitting dampers on
chimneys.  Prohibited outright are direct
openings to the outside such as mail  slots.
Also prohibited are jalousie windows and
skylight constructions (unless the skylights
provide overall reduction of at least 28
dBA) .

Requirements within the 75 CNEL contour are
for a noise reduction of at least 35 dBA.
In addition to the specific construction
requirements needed for 28 dBA reduction
the following are mandatory:  external
doors  of sealed acoustical  design with  an
STC rating of at least 36 dB;  sealed
acoustical  double-glazed windows with an
STC rating of at least 39 dB;  vents to  the
outside having fiberglass lined baffle
boxes in addition to the normal  grills.
The use of exposed beam ceilings is prohibited
unless special plywood and fiberglass acoustical
treatment is provided between  the ceiling and
roof line.  Details of this treatment, or its
equivalent, are specified.

The Building Director would have the power to
require changes in design plans that he deems
necessary to meet the 28 dBA and 35 dBA noise
reduction requirements, according to the
proposed ordinance.  Details of  field tests
are to be specified.
08-008

Cuadra, E.

Environmental Protection Agency, Washington, DC

Office of Noise Control & Abatement
1835 K St. NW, Zip 20036

A FRESH BREEZE  IN STANDARDS WRITING

Sound and Vibration

Vol 5 No  11:24-27, 1971
Noise  ratings  for mass consumer oriented
products  are complicated by the number of
requirements such ratings must satisfy:
1)  rank-order  the noisiness of various models
and  brands of  a  products; 2) relate the
noisiness to sounds  familiar to the consumer
so  that he may easily  interpret the rating
number; 3) provide  repeatable measurements,
so  that the manufacturer can be sure of
conformance, avoiding  the possibility
that he will have to redesign; and
4)  be  simple enough  to be approximated in
the home  rather  than the laboratory, for
purposes  of preliminary screening by regulatory
officiaIs in the field.
                                                    121

-------
08-009
                                           LEGISLATIONS  STANDARDS
    The office of Noise Abatement and Control
    welcomes the cooperation of the various
    professional societies in developing
    measurement standards, because a combination
    of voluntary action and regulation will mean
    better progress  in noise control than
    regulation alone.
    08-009

    Sutton, P.

    Esso Petroleum Co.
    Fawley /England/

    Esso Refinery, Fawley, Southampton,
    England

    NOISE AND THE COMMUNITY

    Annals of Occupational Hygiene

    Vol 14 No 2: 109-117,  1971
4) The corrected criterion, together with the
background noise, is compared with the corrected
noise level to determine the likelihood of
compI a i nts.

Generally, if the corrected noise level equals
the corrected criterion, complainfs are not
likely to  occur.  If it is 10 dBA higher than
the corrected criterion, complaints are likely.

The Standard only enables assessment of the
problem and the prediction of complaints;  it
does not set criteria for acceptability or
limits.   It seems to be a fairly reliable
guide, although one shortcoming is that the
measured nightime background noise level is
often significant I/ lower than the corrected
criterion.   Actual  background noise level  can
vary from  urban to rural areas and is greatly
affected by transient noises such as
intermittent traffic,  dogs barking,  and wind
noise.  Besides these factors, wide variations
exist depending on local activity and noise
from distant sources.
     Increasing attention is being paid to
     neighborhood noise from industrial plants
     and  increasing costs are being incurred in
     noise control.  The first step in neighborhood
     noise control is a realistic assessment of
     noise as a nuisance or source of discontent.
     The  legal position in Great Britain is reviewed
     and the problem of insufficient information on
     public response to the relatively low level of
     noise generated by industrial plants is
     discussed.

     The  ideal is obviously that no one should be
     disturbed, and the only way to do this is to
     keep industrial  noise totally from the
     community.   However, this  is unreasonable, and
     so perhaps the most common criterion is that
     noise be kept as unobtrusive as possible
     without causing widespread or persistent
     comp I ai nts.

     The British  Standard BS4142  (British Standards
     Institution, 1967) sets the following procedure
     for predicting noise complaints:

     1) A "corrected criterion'  is calculated based
     on factors such as the type of neighborhood,
     the  location of the plant  in relation to the
     neighborhood, and the time of day the noise
     occurs.

     2) A measurement  is made of the background noise
     alone  (without the noise from the factory) if
     possible.

     3) The noise level from the factory is corrected
     by factors such as noise character to determine
     the  ''corrected noise  level."
08-010

Hansen, P.

Verein Deutscher Ingenieure,  Duesseldorf
/West Germany/

Ruschenstrasse 20,
43 Essen-Bredency,  West Germany

ACTIVITIES  REPORT FOR 1971

Taetigkeitsbericht 1971

Duesseldorf, Verein Deutscher  Ingenieure,
1971 , 33p.
The Annual Report for 1971 of the
Commission on Noise Abatement of the
German Engineer Association details
its activities in +he field of noise
abatement and control.

As of December 1971, membership in the
Commission amounted to 300 voluntary
workers.   It is subdivided into sub-
commissions and groups  concerned with
the following noise areas: 1) industrial
noise, 2) traffic noise, 3) residential
noise, 4) effects of noise,
5) application of measurement methods,
6) special problems, and 7) less
noisy construction.

The first colloquium of the Commission
was convened  in 1971 and covered the
theme of  'Noise Reduction in Rail  Traffic"
                                                        122

-------
                                                                                                         08-011
                                       LEGISLATIONS STANDARDS
The Commission on Industrial  Noise met
twice with the Commission on  the
"App I i cat ion of Measurement Methods"
and drafted a number of guidelines,
one of which became a DIN-norm.  Many
of these guidelines resulted  from
effort1*- of sub-groups working on the
various subjects of industrial  noise
and some tasks were even undertaken
by pri vate f i rms.

The Commission on Traffic Noise wi^h the
cooperation of the sub-commission on ''Rail
Noise'  held a colloquiurn entitled "Noise
Reduction  in Rail Traffic" on FEB 9, 1971,
in Duesseldorf,  with not only domestic
but also international participation.

In FEB,  1971 the sub-group on ''Rail Noise1'
drafted a guideline on Noise Measurements
in Rail Traffic, which will be printed as
a DIN-norm, after its revision.

The various other sub-commissions and groups
concerned with the aspects of traffic noise
were preoccupied with other research tasks
and the drafting of guidelines.

The Commission on "Residential  noise" met
in OCT 28, 1971 in Duesseldorf.   The main
purpose of this conference was the
discussion on the draft of the VDI  2719
guideline on "sound-damping of windows,"
produced by the sub-commission by the same
name.   II was decided to reedit the draft
and a spring 1972 publication date was set.

Other sub-groups dealing with elevators,
heating systems, armatures and home
appliances, in general, have  also dealt
with noise control  and the establishment
of guidelines in these areas.

The Commission on Measurement Methods has
been busy with other sub-commissions on
guideline draft VDI  2058 "The Assessment
of Occupational Noise within  the
Neighborhood'1.  This commission  also
convened study conferences, such as the
"Noise Reduction in the Bottling Industry"
conference held in Munich in  OCT, 1971.
All manufacturers and operators of bottling
plants agreed to conduct measurements
and comp iIe all pert i nenf da+a in
order  to coordinate plant measurement
tec.iroiogy ,/ith  DIN 45635 'Noise
Measurements in Machines.'

The VDI-Commission on Noise Abatement made
plans to draft guidelines on  the "Constructive
Measures Toward Noise Reduction  - General
Principles" and "Constructive Measures Toward
Noise Reduction - General References".

The importance of this work was  stressed
in a meeting in DEC and a "Sofort"  (Priority)
plan was initiated for the drafting of those
guidelines.  Part of the work is to be
finished by mid-MAY 1972.
In sum total  the Commission has drafted over
18 guidelines,  some of which have already
been pub Iished.
08-011

Caccavari , C.

Chicago Department of Environmental
Control, IL

Engineering Division, Dept. of Environmental
Control, 320 N. Clark St., Chicago, Zip 60610

A NEW COMPREHENSIVE CITY NOISE ORDINANCE

In: Crocker, M., Proceedings of the Purdue
Noise Control Conference, JUL 14-16, 1971

Lafayette,  IN, Purdue Univ, 1972, 594p.,
(p. 263-268)
Chicago's quantitative noise ordinance, passed
in 1957, set a nationwide example, but increased
urban noise required design of a new ordinance
which, after a preliminary study and extensive
hearings, was passed in MAR 1971 and went
into effect in JUL 1971.  The main source of
thrust of the new ordinance is directed at
motor vehicles.  Sales and operational  limits
are both used.  By 1980 all vehicles
manufactured to be sold in Chicago must meet
a 75 dBA criterion at 50 feet from center line
of travel.   By 1978 vehicles travelling at 35
mph or less in the City must emit no more than
78 dBA (motorcycles) and 70 dBA (cars),
respectively,  at the 50 ft distance.  Trucks
(= any motor vehicle with gross weight of
8000 Ib or more) travelling 35 mph or  less
must emit no more than 86 dBA at 50 ft by
the beginning of 1973, including noise from
their auxilliary equipment.

In the month before the new ordinance went
into effect, vehicle measurement teams measured
about 200 motorists per week,  both to develop
proper enforcement techniques and to provide
motorists with a courtesy warning.  In the
first week of  actual  enforcement, 48 vehicles
were given citations, almost all of which were
trucks.

Restrictions on the sale or leasing of noisy
powered equipment or hand tools is given  in
the followi ng  table:
                                                    123

-------
08-012
                                           LEGISLATIONS  STANDARDS
    Type of Equipment
Noise Limit
at 50 ft
     (1) Construction and industrial
     machinery—not  including pile
     drivers, manufactured after:

     1 JAN  1972                            94 dBA
     1 JAN  1973                            88 dBA
     1 JAN  1975                            86 dBA
     1 JAN  1980                            80 dBA

     (2) Agricultural tractors and
     equipment manufactured after:

     1 JAN  1972                            88 dBA
     1 JAN  1975                            86 dBA
     1 JAN  1980                            80 dBA

     (3) Powered commercial  equipment
     of 20  HP or less intended for
     infrequent use  in a residential
     area,  such as chain saws, powered
     hand tools, etc., manufactured
     after:

     1 JAN  1972                            88 dBA
     1 JAN  1973                            84 dBA
     1 JAN  1980                            80 dBA

     (4) Powered equipment intended for1
     repetitive use  in residential areas,
     such as  lawn mowers, small  lawn and
     garden tools, snow  removal equipment,
     manufactured after:

     1 JAN  1972                            74 dBA
     1 JAN  1975                            70 dBA
     1 JAN  1978                            65 dBA

     Restrictions on the sale or  leasing of
     recreational vehicles are as follows:
     Date  of Manufacture after:
                                        Noise Limit
                                        at 50 ft
     Snowmobi le

     1 JAN  1971                            86 dBA
     1 JUN  1972                            82 dBA
     1 JUN  1974                            73 dBA

     Any other vehicle,  including
     dunebuggie,  all-terrain vehicle,
     go-cart, mini-bike

     1 JAN  1971                            86 dBA
     1 JAN  1973                            82 dBA
     1 JAN  1975                            73 dBA

     A further  restriction on the operation of
     recreational  vehicles is that they may not be
     operated on  property zoned  for  business or
     residential  use  so  as to create noise levels
     exceeding  86 dBA at 50  ft.  This  limit
     will  be tightened to 82 dBA at  the beginning

     of  1973.
A restriction on the operation of motor boats
operating in the harbor of Chicago, or anywhere
on Lake Michigan within two miles of the city
limits, is that they may create noise levels
of no more than 85 dBA at 50 ft.   This
Iimit will be tightened to 76 dBA at the
beginning of 1975.

Measurement of all the limits listed above are
to be made in accordance with ANSI, SAE, and
IEEE standards specified in the law.

Noise at the boundaries of construction sites
is not covered in the new ordinance because
it was felt that more technical  data was needed.
Data needed to design noise limits on
construction sites is now being gathered.
Meanwhile, disturbing the peace statutes,
persuasion, and the limit on operating hours
are all being used to achieve some control  over
construction site noise.

Noises emitted from buildings or equipment on
property  is covered by the old ordinance, which
has been modified in the new ordinance in three
ways:

1.  Introduction of the new preferred octave
band center frequencies.
2.  Use of the "A" scale (use of dBA units)
for monitoring purposes.
3.  Noise limits are now applied to the  lot
lines of business, commercial, and residential
property, instead of to the zoning district
boundary  lines as before.
                        08-012

                        Caccavari, C.

                        Chicago Department of Environmental
                        Control,  IL

                        Engineering Division, Dept.  of Environmental
                        Control, 320 N. Clark St., Chicago,  Zip 60610

                        URBAN NOISE LEGISLATION

                        In: International  Conference on Transportation
                        and the Environment, Part II
                        MAY 31-JUN 2, 1972

                        New York, Society of Automotive Engineers, 1972
                        The sources of noise in urban areas, existing
                        regulations in Chicago to control  such noise,
                        and needs for additional legislation are
                        discussed.

                        Transportation noise is the major source of
                        noise  in Chicago.  Trucks operate in close
                        proximity to residential dwellings.   Trucks
                        on  inner city expressways, operating at night
                        at higher speeds that make tire noise a more
                        severe problem, create a very intrusive noise
                                                         124

-------
                                       LEGISLATION & STANDARDS
                                                                                                08-012 (CONT.
problem because of lower background noise
levels at night.  Specialized truck noise
problems occur when large numbers of
refrigerated vans stand at terminals with
motors left running, and when scavenger refuse
pickup trucks (engine noise plus noise from
the packer unit) and oil delivery trucks
(pump noise) operate at night.

In addition to trucks, automobiles and
motorcycles can be noise problems when the
exhaust muffler systems are defective or
modified.  Automobile horns are another
problem, especially when used for prodding
traffic or alerting passengers  waiting
to be picked up.

The older elevated system in Chicago is
a nuisance to the community 24  hours a day.
The subway system affects only  its passengers,
but is a more severe problem in the summer
when train windows are open.

Railroad noise comes not only from pass-bys
on the right of way, but also from switchyards,
where diesels are run night and day.  A new
noise problem is the loading of "piggy-back"
trucks onto raiI road cars in the rai I road yard
near residential  areas—both the noise of the
diesel-driven loading equipment and the trucks
themselves, which are often refrigerated and
left standing with equipment running.   Train
whistle intensity, which has been increased
to penetrate the newer sound proof cars, is
another problem.

Chicago has three regulatory instruments for
dealing with transportation noise:  limits
on new equipment sold for use in Chicago
(Table 1), limits on use (Table 2), and
limits on noise levels at boundaries of
Zoning Districts.

         Table 1 - Sale of new  vehicles
Vehicle Type

1 )





Motorcycles
Same
Same
Same
Same
Date of

before
after 1
after 1
after 1
after 1
Manufacture

1 JAN 1970
JAN 1970
JAN 1973
JAN 1975
JAN 1980
Noise Limit
at 50 ft.
from center
1 i ne of
travel, dBA
92
88
86
84
75
2) Trucks (gross
weight of 8,000
Ibs. or more)   after 1  JAN 1973       86
   Same         after 1  JAN 1975       84
   Same         after 1  JAN 1980       75

3) Passenger cars,
(and any other
motor vehicle)  before 1  JAN  1973      86
   Same         after 1  JAN 1973       84
   Same         after 1  JAN 1975       80
   Same         after 1  JAN 1980       75
The manufacturer, distributor, importer,  or
designated agent shall  certify in writing to
the Commissioner that his vehicles sold within
City comply with the provisions of this section.

Table 2 - Maximum noise levels during operation
of motor vehicles under any condition of  grade,
load, acceleration or deceleration.

                        Noise Limit at 50 ft.
                        distance in Relation
                        to Posted Speed Limit
Type of Vehicle
35 MPH or Less
   (dBA)
Over 35 MPH
  (dBA)
1) Trucks (gross
weight of 8,000
Ibs. or more)

before 1 JAN 1973        88
after 1 JAN 1973         86

2) Motorcycles

before 1 JAN 1978        82
after 1 JAN 1978         78

3) Passenger cars
(and any other motor
veh icle)

after 1 JAN 1970         76
after 1 JAN 1978         70
                     90
                     82
                     82
                     79
This section applies to the total  noise from
a vehicle or combination of vehicles.

As Tables 1  and 2 show, lower limits will  be
required in  the future.  One automobile
manufacturer removed six car models from the
Chicago market because they did not meet
Chicago's law.  Three of these models were
reinstated after exhaust systems were
redes i gned.

The problem of several  trucks with refrigeration
units running simultaneously on a factory
property can not be handled with the motor
vehicles codes, because the individual units
can all meet the noise  limits.  However, in
these cases the property line noise limits
can be used to regulate the nuisance.
In Chicago's enforcement program,  most of the
citations were given to trucks (nearly 50?)
followed by cars and motorcycles.   In addition,
1800 complaints were responded to, not all  of
which proved to be violations.  Most frequently
complained about were air conditioners,
construction noise, scavenger trucks, other
trucks, factory noises and musical instruments.
Even when there was no violation,  the Department
of Environmental Control  made suggestions for
quieter operation, such as moving  the air
conditioner to another location.   In a case
involving residential complaints  about
'piggy-back'1 unloading in a railroad yard,
a violation of the district zoning noise
                                                   125

-------
09-001
                                                  ENFORCEMENT
    restriction was found.  Action was taken
    inducing the railroad to undertake a major
    noise reduction program, including removal
    of refrigeration units to a different yard
    and design of sound absorbant enclosures for
    the diesel engine and mechanized arms of the
    unloader.  The program will gradually reduce
    noise from the railroad yards to the legal
    limit of 55 dBA at the residential/manufacturing
    zone boundary Ii ne.

    Excessive hornblowing has been controlled using
    the provision of the ordinance prohibiting use
    of any audible device on a moving vehicle
    unless it is an emergency, and no use whatsoever
    while the vehicle is standing.  This provision
    is also used to restrict excessive noise from
    ice cream trucks.

    A drawback to the present  limits on sales of
    new vehicles is that the manufacturer may be
    faced with a multiplicity of local and state
    requirements.  Uniform federal regulation of
    noise from new equipment would ideally solve
    this problem, and still give local governments
    the option of setting more stringent use
    requ i rements.

    Local  restrictions would be need€;d even if
    Federal  restrictions on noise sources were
    set.  One example is trucks accelerating
    from a stop sign in a residential area.
    Another example is the grouping of trucks
    with refrigeration units, although the
    individual trucks could meet Federal limits.
    Finally, construction equipment could meet
    Federal  standards individually but when
    operating all at once on a construction
    site,  create a community noise problem that
    should be regulated locally.

    Another problem is that it is financially
    impossible for cities like Chicago,  New York,
    and Boston to replace existing mass  transit
    systems  with something quieter.   Controlling
    this noise source will  be a slower process,
    with the gradual  purchase of quieter equipment
    and installation  of smoother rails.   Cities
    buiIding new systems should not repeat the
    mistakes made by  those with existing systems.

    A problem in enforcing against railroad noise
    is that  noisy rolling stock is owned by dozens
    of different lines,  and the local yard has
    little control  over what comes in.  This is a
    suitable area for Federal  action.

    Proposed Department of Transportation standards
    for noise from new expressways—recently revised
    to 70 dBA at the property line—will  be only
    marginally useful  in protecting adjacent
    residential  communities because the 70 dBA
    number is too high.   Noise problems  around
    existing airports occur because buildup of
    residential  communities close to traffic
    patterns has been allowed.   With present
    knowledge of airport noise, it should be
    possible to avoid similar problems in the
    future through land use planning.  Information
    of the design guide type, supplied by several
    Federal  agencies, can be useful  only if it is
    incorporated into the development and growth
of our urban areas.  The EPA should provide
both technical  and financial assistance to
state and local  agencies.
09-001

Schenker-Spruengli, 0.

Schweizerische Liga Gegen den Laerm
Zurich /Switzerland/

PROGRESS OF NOISE ABATEMENT  IN SWITZERLAND

Fortschritte der Laermbekaempfung in der
Schwei z

Laermbekaempfung

No 3:27-28, 1969
Since 1957 Switzerland has established a
Federal  Expert Commission for Noise Abatement.
It consists of 52 experts and is divided into
5 sub-commissions dealing with the following
probI ems:

1) Medical, acoustical and technical
principles,
2) Motor vehicles, Railroads, Ships and Cable
cars,
3) Aviation noise,
4) Construction and industry noise, Sound
protection in buildings, etc.,
5) Legal problems.

It has accomplished considerable progress with
the cooperation of the Swiss League Against
Noise.  The biggest enlightment action resulted
in 1962 through the conference of city police
directors  in which 150 communities participated.
In 1963 a  special instructional  course in Noise
Abatement  and Control  for law enforcement groups
was conducted in Zurich.  The League also
conducted  4 big scientific conferences, 6
technical  exhibits and numerous demonstrations
concerning the practical and technical aspects
of noise abatement.

One big progress is the establishment of the
recommended noise levels.  The noise  levels
are measured on a dBA scale according the CEI
publication #123 taken  in an open window.
Background
Noise
Night Day
35 45
45 55
45 60
50 60
55 65
60 70
Frequent
3eaks
Night Day
45 50
55 65
55 70
60 70
60 75
70 80
Occas iona I
Peaks
Night Day
55 55
65 70
65 75
65 75
70 80
80 90
Zone

A
B
C
D
E
F
                                                        126

-------
                                                                                                         09-002
                                               ENFORCEMENT
A - Recreational  areas
B - Quiet residential  areas
C - Mixed areas
D - Commercial  areas
E - IndustriaI  areas
F - Main traffic artery

Desirable Values: about 10 dB less, however
not below 30 dBA
Background noise: mean value (average level,
w i thout peaks)
Frequent Peaks: 7-60 sound peaks per hour
Low Peaks: 1-6 sound peaks per hour

Also many other reasons and ordinances were
instituted, for instance:  the health insurance
was revised to incorporate hearing loss as an
insured occupational illness; the establishment
of Noise Abatement Commission in various cantons
and cities; and Noise Abatement offices
supervised by the police in many cities, as
Basel, Bern, Lausanne, Luzern, Lugano and Zurich.
Zurich's office is an exemplary and most
active one.

The biggest battle  is civil supersonic
overflight.  Much has been done, although
much still remains to be accomplished.
 09-002

 Smith, W. A.

 University of South Florida, Tampa

 NOISE CONTROL LEGISLATION  IN FLORIDA

 At:  Noise Control Workshop, Harriman, NY, JAN
 18,  1972

 Tampa, University of South Florida,  1972, 4p.
Activities of the Florida Legislature  in the
area of noise control are discussed.  The
State Environmental Protection Agency has been
given authority to set standards.  The State's
particular  interest  is vehicular noise and it
wi I I set up noise test equipment at  its Motor
Vehicle Inspection stations.

State and  local governments are  interested in
control Iing noi se, but are not yet willing to
fund it.  There are no noise control experts
on the State EPA staff.

Most local ordinances are "do not disturb the
peace'1 variety except for a few which set
noise  limits.  For instance, a cement plant
was forced to close when it could or would not
bring  its noise down to acceptable  levels.

A  survey was made by acoustics students of the
University of South Florida to test the effect
the new proposed standards, such as the Chicago
Ordinance, would have on the noise  level.  The
results showed a small  percentage of violators.
Among those found, the worst offenders were
trucks and motorcycles.

Florida hopes that the new national noise
standard for vehicles will be set considerably
lower than those of the present Chicago
Ordinance and that the enforcement wi I I  become
part of the annual motor vehicle inspection
p rogram.
09-003

Warren, D. G.

North Carolina Univ., Chapel  Hill

Institute of Government, Chapel  Hill, NC

THE PROBLEM OF NOISE: HAS ANYONE HEARD AN
ANSWER?

Popular Government

Vol 38 No 2:16-19, 1971
A discussion of noise pollution and laws,
ordinances and legal  actions which involve
noise is presented.

Noise is generally defined as unwanted sound.
Too much exposure to it obviously induces
hearing loss, along with heart disease,
migraines, intestinal disorders and some
allergies.   It also  interferes with
conversation, hinders concentration and
disturbs sleep.

A study of the Maban tribe in Africa revealed
that its noise-free society left 70 year old
men with hearing as acute as the average 20
year old New Yorker.  An estimated 5,000,000
American males from ages 10 to 59 have some
degree of hearing  loss, and 1,000,000 need
hearing aids.

A number of  legal tools against noise are
avai lable and have been put into effect in
some areas of the U.S.   The private nuisance
action, for  instance, has been used to a
small  degree in North Carolina.  This is a
civil  tort, and to be used, the interference
must be both a substantial  and a legal cause
of the harm  involved.  Public nuisance affects
the public as a whole.   Anything acted upon
under this action must  interfere with public
health, safety and peace.  The nuisance
ordinances now in effect are very vague.  There
is no clear guideline as to what really creates
a nuisance.  Furthermore, citizens themselves,
may be unwilling to go  through the trouble
and expense of court action.
                                                    127

-------
09-004
                                                   ENFORCEMENT
     In North Carolina, a farmer complained that
     aircraft take-offs and  landings  in the space
     directly above his chicken farm were an
     unconstitutional taking of his property
     (U.S. v. Causby).  He was awarded damages
     under the  inverse condemnation principle,
     which has  been applied only against aircraft.

    Antinoise  laws must be aimed at preventing or
    controlling noise.  Most of the traditional
     laws are zoning, antinoise ordinances, and
    muffler controls; some of the new measures
    are called decibel ordinances.

     If used properly, zoning can be a great aid
     in noise abatement and control.  It can
    separate industry and busy highways from
    residential areas, for example.  In order
    to be effective, however, it must be used
     in conjunction with other planning efforts.

    California, Connecticut and New York have all
    enacted decibel ordinances with maximum
    noise levels which traffic noise must not
    exceed.  Although difficult to enforce, traffic
    noise has  been reduced.

    The answer to noise control lies in the
    cooperation of industry, government, city
    planners and individual citizens.
produced by the City Police, entitled "Noise1,
was shown  in various neighborhood movie-houses
and in schools throughout the week.

The whole teaching community was requested to
dedicate at least 2 hours of their teaching
program on the environmental topic.  For
this purpose, a document was distributed
to the teachers.  One section of the document
entitled, "Will we, should we, destroy ourselves
by Noise'1 was prepared by the Noise Abatement
Office.

The tasks and methods of the Noise Abatement
Office were investigated by BBC of London and
Norwegian TV.  Officials from London, Washington
and other parts of Switzerland also visited
the of f i ce.

The following statistics show actions of the
Noise Abatement Office recorded by noise
sources:
     Noise Source
                                1970
                                        1971
1.  Traffic Noise (Various
types of Motor Vehicles)

2.  Construction

3.  Commercial  Noise (incl.
restaurants & private
clubs)
                                 642    1,016

                                 863      898
                                                                                                 433
                                                                                                          502
    09-004

    Birchler, F.

    City Pol ice
    Zurich /Switzerland/

    ANNUAL REPORT 1971 OF THE NOISE ABATEMENT
    OFFICE

    Jahresbericht 1971 der Laermbekaempfungsstelle

    Zurich, City Police, JAN 4, 1972, 3p.
4. Other Noise Sources
(household, neighbors,
animals, churcnes,
schools, etc.)
                                 527      583

                               2,465"    2,999"
Out of 618 vehicles cited for noise violations
in 1971, 27 we^e condemned;  125 inquiries
concerning noi<;e abatement measures were
answered by mai  I; 1402 interviews were granted;
16 frequency analyses were plotted; and 3037
inquiries were processed by  phone.  Only 8
of 2465 recorded actions could not be completely
resolved.
    Activities and actions of the Noise Abatement
    Office of Zurich during 1971 are outlined in
    the Office's Annual Report.

    The Noise Protection Law of 1971 was
    promulgated by decree of the Zurich Municipal
    Council.  The law was reviewed by the
    Cantonal Health Office and put into effect on
    SEPT 1, 1971.  This law has been quite
    effective and successful in the enforcement
    of the prescribed noise measures during the
    4 months since its promulgation.

    The 'Zurich Environmental Protection Week'
    took place between MAY 3-8, 1971.  The
    program was arranged by the Acoustics Department
    of the Health Inspection Office and the Noise
    Abatement Office of the City Pol ice.  A film
Kvitka, V.

NOISE FROM THE SKY

Science and Engineering Newsletter of Novosti
Press Agency

No 11(525):1-4
Current approaches toward solving the problem
of aircraft noise in the USSR include
introduction of a new generation of aircraft
                                                        128

-------
                                                                                                         10-002
                                          PROGRAM PLANNING
with high bypass ratio engines, restrictions
on building near airports,  and flight
operating techniques for noise reduction.

The noise during take-off from IL-62 and TU-154
airliners, which have bypass turbojet engines,
\i.  ,-12 dB lower than that of the older
generation of Soviet commercial jets.  In
order to reduce noise of the exhaust jet on
new planes a special noise-reducing nozzle
operates only during take-off and, consequently,
docs no1 affe':V the flight performance of
the plane.

At present both construction of new airports and
expansion of old airports is regulated for the
purposes of noise abatement.  Town building
near airports is restricted.  However, new
regulations are being prepared by the USSR
Ministry of Health and USSR Ministry of Civil
Aviation.  These are presently in the form of
recommendations on the zoning to provide
rational planning near airports.   But they
are being submitted for approval  as normative
standards i.e. standards given the force of
I aw.

Changes in piloting methods have yielded a
reduction of 5-8 dB, measured under take-off
paths, and of 7-16 dB during flight over
communities by means of thrust reduction.
Although there is a substantial increase of
noi?e at the airport during the take-off
ru<^ of SST's, due to the high thrust of the
engines, this same high thrust enables the
SSI to climb steeply.  Thus, there will be
rather  low noise levels at the second  ICAO
take-off gauging point, which  is  located
about 600 meters from the start of rol I .
Furthermore, the Soviet SST engines are
to be fitted with devices for supply of
secondary air flow  into the exhaust jet,
\ielding a 5 dB noise reduction during
take-off.
The prediction of 50 to 75? reduction is based
on the following factors:

1)  The FAA regulation requires new generation
aircraft to be approximately half as loud
(10 EPNdB quieter) than present generation
aircraft.  The 747 is covered by the new
regulation and meets its requirements,
but it will take 15 to 20 years before most of
the present noisy generation of aircraft
has been phased out.

2)  In the shorter time frame of 5 years,
there is hope for a reduction if a retrofit
program is carried out on existing aircraft.

3)  With community pressure and perhaps
some technological breakthroughs, it may
be possible to achieve a 20 EPNdB reduction
within 20 years.

Criteria for residential development near
an airport with a large number of flights are:
If the noise level exceeds 100 EPNdB,
development would not be satisfactory;  if the
noise level is in the 90-100 EPNdB range,
development is marginal, and should only be
undertaken with strict sound proofing
requirements in the initial building design.
 10-003

 Man, A.

 Israeli Medical Corps

 NOISE POLLUTION

 In:  Marinov, U., The Environment in  Israel,
 Israel National Committee on Biosphere and
 Envi ronment
Inglewood Department of Environmental Standards,
CA
STATUS OF AIRCRAFT NOISE POLLUTION

Inglewood, CA, City of Inglewood, FEB 1971, 2p.
The FAA measures aircraft noises in terms of
effective perceived noise decibles (EPNdB).
Ninety EPNdB would be termed noisy, 100 EPNdB,
very noisy;  and 110 EPNdB,  extremely noisy.
Each increase of 10 EPNdB would be judged to
sound approximately 'twice as loud."  Present
noise levels near the airport due to jer
aircraft range from 90 to 120 EPNdB.
                                                            Jerusalem,  1971,  60 p.  (p.  27-29)
A brief account  is given of particular
noise sources, anti-noise  laws, and noise
control organizations in Israel.

Because of the country's mild climate, the
population is outdoors-oriented, and spends most
time inside with windows open.  Environmental
noise thus leads to psychoacoustic irritation,
although not usually to a  loss of hearing.

Major sources of noise are buses and
motorcycles, workshops in  residential areas,
and  industrial plants, and loud discotheques
and other places of entertainment.  The
textile, cement, and metal  industries are the
noisiest in Israel, and produce sound levels
above the criteria considered harmful to the
ears.  Aircraft noise is becoming an
increasingly serious problem.  Agricultural
machinery is also beginning to create noise
problems.  In addition, almost every young
                                                    129

-------
10-004
                                               PROGRAM PLANNING
    man and many young women have been exposed to
    shooting or explosions during military service
    and later in the reserve service.

    A non-specific anti-noise law, the Kanowitz
    Law, now in existence is being amended and
    standardized.  By-laws have also been passed
    in regard to industrial  noise and directives
    have been issued concerning hearing-loss
    compensation.

    Governmental institutions which deal  with noise
    problems include: the Unit for the Prevention
    of Air Pollution and Radiation Hazards of the
    Ministry of Health; the Unit for Prevention of
    Noise Hazards of the Israeli Medical  Corps;
    the Ministry of Labour;  the Institute of
    Standards; and a governmental  committee assigned
    to ammend the Kanowitz Law.  Academic
    institutions include the Acoustic Department of
    the Technion in Haifa and the Department of
    Electronics at the Weizmann Institute in
    Rehovot.  There are also a number of  private
    organizations serving as advisers on  noise
    problems to various industries and construction
    companies.
    10-004

    EPA ANALYSIS OF NOISE PROBLEMS POINTS WAY TO
    FUTURE LEGISLATION

    Automotive Engineering

    Vol 80 No 4:28-35, 1972
    A discussion of the Report to the President
    and Congress on Noise by the Environmental
    Protection Agency is reviewed.  The Report
    presents a summary of the present noise problem
    and status of  legislation, and the solutions
    and directions that engineers and legislators
    will probably be taking over the next 15 years.

    Aircraft noise, followed by highway noise,
    has received the greatest Federal attention in
    transportation noise abatement.  At present,
    Federal regulations are still in the development
    stage for retrofitting aircraft for noise
    control, controlling sonic boom, and
    certifying SST and STOL/VTOL-type aircraft.

    The EPA survey reveals that many states
    have enacted noise control legislation—
    nine states  in the first six months of
    1971 alone.  Laws are incorporating specific
    decibel limits.  Florida, New York, Illinois,
    Hawaii, and North Dakota now have departments
    with the authority to set noise standards.
    California regulations require the airport
    operator to monitor take-off and  landing noise
    and to set a noise impact boundary around the
    ai rport.
Five states have set  limits on total vehicle
noise based on subjective standards.  Five
states require mufflers on motorcycles.
California, Colorado, and Minnesota have set
overall  limits on these vehicles that become
tougher with time.  Five states currently
require mufflers on boats.  Snowmobiles are
receiving more attention, with Maine and
Wisconsin requiring mufflers and Montana,
New York, Colorado, and Massachusetts setting
limits on new snowmobiles (the latter two
states also regulate snowmobile operating
noise).

The noise recuctions obtained with new
aircraft largely stem from improvements in
engine bypass ratios, fan designs, and new
designs for inlet and discharge ducts.
However, because of the  large numbers of
older aircraft in use, most aircraft now in
use exceed the Federal Avioation Regulation
limits for new aircraft.

The noise produced by highway vehicles stems
from three major causes:  tires and aearing,
the engine and related accessories, and
aerodynamic and body noise.   Despite their
larger engines and tires, newer vehicles are
auieter than older vehicles.   Diesel  powered
trucks are 8-10 dB noisier than gasoline-
powered  trucks, and 12-18$ noisier than
automobiles.  One engine manufacturer estimates
a  $1,500 increase in the $5,000 base price of
a  250-hp diesel engine to drop noise 10 dBA.

Recreational vehicles—motorcycles, snowmobiles,
all terrain vehicles and pleasure boats often
reach levels of 92 dBA.  Typical  noise levels
contributed bv the various subsystems in a
motorcycle range from 59-69 dBA at 20 mph
to 78-86 dBA at 60 mph.  Most motorcycle noise
reductions have been achieved by exhaust
system changes.  Snowmobile noise stems
primarily frori poorly muffled exhaust systems.
Current models generally are in the 77-86 dBA
noise band.  EBoth inboard-and outboard
powered pleasure boats range from 65-105 dBA at
50 ft, with exhaust systems being the major
noise contributor.

Typical  noise  levels measured 50 ft from
construction equipment range from 72-96 dBA for
earthmoving equipment from 75-88 dBA for
materials handling equipment, and from 70-87 dBA
for stationary equipment.  In almost all of
this equipmen"1", the e.ig'ne is the primary
source of noise.

EPA concludes that for engine-powered equipment,
the qreatest noise reduction may be obtained
by quieting the engines.
                                                        130

-------
                                                                                                         10-005
                                           PROGRAM PLANNING
 10-005

 Munich /West Germany/

 MUNICIPAL-POLITICAL ASPECTS OF
 ENVIRONMENTAL PROTECTION  IN
 MUNICH

 Kommunal Politische Aspekte des
 UmweItschutzes  in Muenchen

 Arbei tsberi cht  zur Fortschrei bung
 des Stadtentwicklungsplanes Nr 3

 Munich,  1971, 163p.
Since JAN 4,  1971 Munich's council group
presented six proposals with 40 individual
points for an effective Environmental
Protection Plan  for the city.  A greater
publicity program, improvement of
measurement systems, restrictions on
individual traffic, introduction of
exhaust-free vehicles, restriction of
certain refuse,  better supervision of
water and vegetation resources and a
catalogue with special preventive
measures are beinc planned.  Proposals
are established  en the basis of studies
of these measures.

A general inquiry and survey of all the
big cities in the German Federated
Republic helped  to set up this working
group and establish these plans.

According to the proposal #255 (der
Gesamtdeutschen  Partei) of JAN 9,  I97I,
the following is planned:

I)  A network throughout the city with
separate detectors for automatic
measurement of traffic flow and air and
noi se polIution.

2)  Constant observations of the  influence
of traffic on health, independent o*
weather, season  and time (daily) factors.

Special noise measures are proposed to
include:  strict rupervision of all
construction work, consultation with
builders, and investigation of new
construct ion.

Improvement of traffic flow on national
and state highways and main arteries of
the city and construction of park and
greenbelts and other means of traffic
directions are anticipated.

A street directory of the city district
is planned with  the description of its
present situation, excluding the
strictly residential  areas.

The Office or Economy  Is  responsible
for the measurement of  landing and
take-off  noise at the  Munich  airport.
For noise-reduction purposes the city
council recommends the following
measures:

1)  No flight paths over the city
(especially supersonic).

2)  No over city flights by old
ai rplanes.

3)  Restriction on the number of
helicopter observation flights.

An  inquiry was conducted which
showed that 63? of residents of heavily
populated areas complained about noise.
A noise level ranging from 30 - 90 Phon
can cause insomnia, disturb rest resulting
in a reduced concentration span,
decreased productivity, irritability and
nausea, affect the vege+ative nervous
system, cause gastritis and colitis,
increase metabolism,  lessen proper
circulation and also cause
arteriosclerotic changes, as well as
psychic illness.  Levels above 90 Phon
cause physiological damages such as
hearing loss or other hearing problems.

According to the proposed prognosis the
vehicular traffic will  increase about
55? by  I985.  This means an increase of
1 - 2 dBA, and because the speed will
increase, 4 dBA will be added.
Physiologically this means that the noise-
level of street-traffic will increase
about 50?.   In addition, a 70?  increase
in  large aircraft  in civil flights can be
expected.

Special emphasis is put on public-
opinion and media, such as the press,
television and radio to inform the
general public and arouse greater
interest.

Munich teachers and scientists are
asked to form workshops to introduce
interdisciplinary courses in the field
of environment.  Presently only the
biological aspects are encompassed
in the environmeital curriculum.

A commission selects short films
about various themes of environmental
protection.  These films are offered
weekly to the  local theater.
Amusement taxes serve to finance these
films.  A 4% budget increase in social
products  is suggested.

'n order to have greater enforcement
of the existing laws,  increased
fines and other penalties
(especially in  respect to water-
pollutants)  are recommended.
Enforcement measures and
further research  is encouraged concerning
restrict, ions on city overflights,
stricter supervision over construction
noise,  improvement of  damping  materials
                                                    131

-------
10-006
                                               PROGRAM PLANNING
    and devices and other preventative
    measures like greenbelts, earthbanks,
    divj sunken highways for Traffic.
    In this respect, recommendafions for
    public transportation are proposed.

    In order Tc set all  the proposals
    int  action,  formation of project
    groups is necessary.   Presently there
    are 11 of then  dealing with various
    arpeci; of  environmental  protection.
    Schwe izeri sche Liga Gegen  den Laerm,
    Zi-ricn  /'Sv. i rzerl and/

    PPCGREfj  OF NO ISC ABATEMENT IN SWITZEPLAN

    rorfschri tte der Laermbekaempfung in  der
    Schwe i z
The present major program is the national
campaign against civil supersonic jefs.
10-007

Kraege, R.

Institut fuer Schall- una Schwingungsfechnik,
Hamburg /West Germany/

2000 Hamburg 70, Fehmarnstrasse  12, West
Germany

NOISE MEASUREMENT CONDUCTED BY THE PARCEL
POST OFFICE IN HAMBURG

Laermmessungen bei  der Paketpost in
Hamburg

Kampf dem Laerm

Vol 19 No 1:6,  1972
    After the Noise Abatement '_eague of Switzerland
    w=is formed and achieved considerable progress
    in its efforts, the government came to its
    support and endorsed in October  1957 the Federal
    Exoc-f ? '-"Trillion for Noise Abatement.  This
    commission for Noise Aba+enenf,  cornposec of
    52 ^xperls from +he various seicnlific fields,
    war- O'vced info 5 sub-comrru ssions :

    1) medical, acoustical  and technical  principles;
    ?} motor xeb'oles, rai Iways and  ^hips;
    3) aviation no I so;
    4) construction and industrial noise, sound
    protection in residences, etc.;
    5> ;u'Hi'iid! o rob] ems.

    After five years of study a comprehensive
    report was published in 1962.

    ln^ League has conducted education programs
     i    
-------
                                                                                                         10-008
                                          PROGRAM PLANNING
10-008

Munich /West Germany/

On:  LOCAL POLITICAL ASPECTS OF ENVIRONMENTAL
     PROTECTION IN MUNICH

KommunaIpolitische Aspekte des UmweItschutzes
in Muenchen

Arbe itsbericht zur Fortschrei bung des
StadtentwicklungspIanes Mr.  3

Munich, 1971, 163p.  (p. 55,  68-70)
                           As to industrial noise, a federal  law is
                           planned to enforce noise reduction techniques
                           in all kinds of machinery and equipment.

                           In spite of increased costs, measures should
                           be taken to continue and improve building
                           techniques.  Careful planning of residences
                           and other structures is also recommended.
A draft paper discusses proposals for
prospective noise laws for the city of Munich
in light of draft norms for the Federal
Republic of Germany.

No noise-measures have been established as yet
in Munich.  Single noise sources are
investigated solely when there is a complaint.
So far only a system for aviation noise-
measurements has been set up.

Presently the Federal German Republic is
compiling general norms.  The draft encompasses
the following noise  levels:
      Area

Strictly  Industrial areas
Predominantly industrial area
M i xe d a rea
General residential areas
Strictly residential area
 Day
(dBA)
 70
 65
 60
 55
 50
 Night
 (dBA)
70
  50
  45
  40
  35
The  law against aviation noise would contain
two noise-projection zones.

     Zone I    - noise exposure over 75 dBA
     Zone I I   - noise exposure over 67 dBA

Traffic noise ordinance would limit noise
levels as folIows:

Passenger car - max 84 dBA
Trucks - max 89 dBA
Motorcycles - max 84 dBA

AI I measurements are taken at a 7 meter
di stance.

During night hours  (between 10 pm through 6 am)
all trucks would be restricted in most areas
with the exception of the city's main arteries
and purely industrial areas. (Proposals No.
255/6DP #3A,  No. Z85/6PP #2).

Since APR 1,  1971  flight take-offs are limited
between 8 pm to 6 am, with the exception of
mail and freight carriers (No. 255/6DP #1).

Overflights of  cities for purposes of
advertisement or observation are considered
unnecessary  and should be eliminated. (No.
285 GDP #3).
                            10-009

                            Brown,  L.

                            THE  PERMITTED  NOISE  LEVELS  FOR  HEAVY  VEHICLES
                            ON OPEN  ROADS  ALREADY  EXCEED THE  NOISE  LEVELS
                            FOR  JETS AT  HEATHROW

                            Municipal  Review

                            Vol  42  No 493:149-150,  1971
A retrospective study covering two years of
admissions to a psychiatric hospital shows
that there is a significantly higher rate of
admission, especially in certain diagnostic
categories, from inside an area of maximum
noise arising from the Heathrow Airport than
from outside this area.

Such information has lead to greater concern
over noise in Great Britain.  The realization,
based on scientific research, has hit that
noise is not just an irritant, but  is
definitely a mental and physical health hazard.

Some noises are accepted as a part of everyday
life, while there are others that we simply
get used to.   But in our rapidly advancing
technological society, noise levels are
advancing also, and there is no getting used
to them.

The Noise Abatement Society (NAS) was formed
in Great Britain in 1959.  An independent and
non-political pressure group, it receives no
financial or other help from the government.
Both corporate and individual  memberships are
included, and over 600 local authorities are
members.

The society encourages authorities to pass by-
laws of  noise levels and makes efforts to
persuade industry to develop quiet equipment.
In another activity, the Society last year
aided London  in holding a "Quiet Week" and an
exhibition of silencing equipment.

In its troubleshooting capacity, the NAS will
aid any  authority that considers noise a major
environmental problem.   The officers know the
official procedures and the correct channels
through  which to go for a solution to the
probI em.
                                                    133

-------
10-010
                                               PROGRAM PLANNING
    Mr. Geoffrey Holmes, Technical  Adviser to the
    NAS and Chief Public Health Inspector, Royal
    Borough of New Windsor,  has very definite views
    of the problem of noise  control  and abatement.
    He estimates that at least 10%  of his work is
    concerned directly with  problems of noise and
    the community.

    For instance he relates  the problem of traffic
    noise to its routing, such as the time when the
    opening of a new bridge  caused  traffic to go
    straight into the town of Windsor.  The Public
    Health Department had just completed a survey
    which showed tht 35)5 of  the midday traffic
    consisted of heavy lorries.  Noise levels rose
    more than 10 dB over those laid  down by the
    Wilson Committee.  In fact, the  permitted noise
    levels for heavy vehicles already exceed those
    for night jet flights at Heathrow Airport.
    In addition a "canyon effect" produced by
    traffic in narrow streets could  raise the noise
    level  6 dB greater, exceeding the daytime
    aircraft noise limits.  Mr. Holmes' solution to
    traffic noise is to confine lorries to specified
    routes.

    Taking action on a traffic noise problem, Mr.
    Holmes was confronted with the  situation in
    which a residential road was being used by
    heavy traffic as a short-cut to  the docks.  By
    merely writing to the companies  whose lorries
    were using the route and explaining the
    discomfort they caused the neighborhood, Mr.
    Holmes won his case.  The firms  cooperated by
    re-routing thetr lorries.

    He took a similar stance with regard to
    aircraft noise at Windsor.  The  noise is worst
    during the three months  of the  year when,
    because of strong winds, aircraft must come  in
    and go out oy way of the borough.  The problem
    is that if minimum noise routes  are not followed
    the noise can be quite loud.

    Convinced that some aircraft were not following
    minimum noise routes, Mr. Holmes sent a report
    of his suspicions to "the Board  of Trade.  As
    a  result, two major airl  ines were found to be
    ignoring the routes.  Since then, the situation
    has been much improved.   At present noise
    committee meetings being held at the Board of
    Trade have representatives from  the airlines but
    not from the  local  authorities.

    Looking at America there  is apparently a  lack of
    governmental concern.  Boeing is so concerned
    that  it has made a mathematical  model for
    evaluation of the various means  of reducing
    aviation noise.  Tests have shown that any
    technological changes will be complicated and
    expensive, and  in Mr. Holmes' view, the only
    solution  is to keep people and aircraft apart
    by proper airport planning.

    The NAS, together with other concerned
    organizations, has agreed that the third London
    Airport should be  located at Foulness.   If
    situated  inland, they conclude,   it would
    sterilize and spoil a large area of countryside.
    Besides inland siting would create dangerous
    probI ems  in air traffic  controI  .
Airport expansion is not London's problem
exclusively; it is the concern of municipal
airports as well.  Mr. Holmes says, one
wonders if sufficient regard is being paid to
the people and districts surrounding these
airports.   Airport noise is more of a problem
than traffic noise.   The big jet is very
annoying because of  the high frequency element
in the noise.   At least if  heavy noise was
confined to certain  routes  the noise would be
localized, but no such remedy can be taken with
a i rcraft."
10-010

Schuler, K.

Kamekestrasse 37-39
Cologne /West Germany/

NOISE REDUCTION IN PUBLIC PASSENGER
TRANSPORTATION, ROLLING STOCK AND
INSTALLATIONS

Laermmi nderuncj bei Betriebsmi tte I n und—
anlagen des oeffentIichen Personennah -
verkeh rs

Kampf dem Laerm

Vol  18 No 5:157-130,  1971
The German Feceral  Traffic Minister Leber,
while speaking at a session on subway and
motor vehicle construction, made an appeal to
employ all possible means for noise reduction.

The manufacturers and the public transit
concerns have tested various noise reducing
measures, such as sound-damping materials and
construction techniques.

Experiments were held in 10 plants on 30
railed vehicles, street-cars and subway cars.
Polishing of the tracks results in the most
noise level reduction, but spraying the tracks
with water and sand not only quiets the ride,
but also assures a  much safer braking power.

It was observed that heavy snow is an excellent
noise-reducing agent.   It is suggested that a
similar artificial  type of covering would be
an excel lent abatement measure.

Chemical processes  are being applied to abate
the "multitonal whines" of overhead tracks in
the interim before  they are totally replaced.
In addition, 70 to  100 cm high sound protection
walls are being constructed as noise reducing
devices.  One chemical abatement method, curve
lubrication, has proved ineffective.

The investigat'on of the tunnel construction  in
Munich, where "he tunnel is deeper and the
                                                        134

-------
                                                   DATA
                                                                                                         11-001
vehicles wider, disclosed that the thicker
tunnel walls contributed considerably toward
noise reduction.

Use of trolley-cars  (0-Bus) declined  in 1971
in favor of the more economical Diesel-bus,
which  is too  loud because of  its motor and
tires.  The Electro-bus  (E-Bus), a totally
electrical bus, made its appearance  recently;
it is  economically  less  feasible than the 0-bus.
Since  fiscal  considerations dictate  the present
Diesel-Bus, casing  and damping measures to
solve  at  least  the  present noise situation
are strongly  recommended.
 11-001

 Pinter,  I.

 Orszagos  Munkaegeszsegugyi
 Intezet,  Budapest /Hungary/

 HEALTH PROBLEMS OF NOISE
 IN MAN'S  ENVIRONMENT

 A Zaj Egeszsegugyi Problematikaja
 az Ember  Kornyezeteben

 Orvostudomany

 Vol 22 No 2:241-245,  197!
Noise measurements were recorded in
Budapest  in schools, medical institutions,
and  in the areas surrounding industrial
plants and airports.

Measurements were taken of outside
noise, chiefly from traffic, in 15
Budapest  school buildings,  13 of which
were  in the inner city, one on the main
traffic artery, and one on the outer
edge of the Capital in quiet
surroundings.   Measurements were taken
two or three times in each school,
from 8 am to 4 pm, for a total  of
eight hours per school.  The dBA levels
and octave band levels were measured.
Noise was measured 2.5$ of the time, or
up to 1.5 minutes in an hour.  With
one exception, the noise level  of the
classrooms facing the street in inner
city schools exceeded medically sound
limits.   Classrooms facing the
courtyard were observed 15 to 25 dBA
lower in noise pressure level.

Studies  to determine the amount of noise
entering hospitals from the outside,
chiefly  vehicular traffic noise, showed
that rooms facing the street had a noise
level  approximately 40 dBA greater, in
certain  cases, than rooms on the
courtyard.  The noise level  of  the
hospitals far  exceeded health norms,
especially in the 50 to 250 Hz octave
band.  Only the suburban Korany
Tuberculosis Institute had a lower
noise level.  (See Figure 1.)
     Noise  Level at 2nd Surgery Clinic (2SC)
and Nat'l Korany TB Inst (NKTBI) Measured in
Octave.,Bands with Windows_O^en and Closed
    Medium Frequency Octave Band,  Hz
           Figure 1 ,
Noise measurements were taken  in the
area of the Goldberger Textile
Printing  plant which  lies  in the Obuda
reconstruction area  in which a new
residential community  is being
developed.  Houses are to  be built
40  to 50  meters  from the north and
east sides of the plant.   The  purpose
of  the tests was to serve  as preliminary
data for  noise protection  in the new
houses and for noise abatement
measures  to be executed in the plant.
Prevailing noise  levels at various
times of  the day were measured at
91  points on the streets bordering the
plant.  Base noise was measured when
the plant was shut down.   Most
measurements were taken at 1.5 meters
above the street.  While the plant was
in  operation, the noise level  on the
north side was about 30 dBA above the
allowable daytime  limits and about 40 dBA
above the allowable nighttime  limits.

Noise measurements were taken  at the
Budapest-Ferihegy  International
Airport to establish the present noise
level and to project the aircraft noise
effect of a planned second runway on
nearly residents.  Measurements were
taken on  a direct  line between the
runway and the Capital, mostly between
840 and 4200 meters from the end of
the runway.  Four other measurement
points outside this area were  also
used.  Data were compiled  on the
noise produced by 90 various types of
aircraft  during  take-off and  landing.
Data were recorded on the  maximum
level measured during an overflight,
the duration of  the noise, the
number of planes and the time  of day.
                                                     135

-------
11-002
                                                       DATA
     Maximum noise  level was measured  in
     octave bands and expressed  in PNdB
     (annoyance  index).  An evaluation
     was made on the basis of the Wesf
     German Sforindex Q which recommended
     compatible  land use planning for  the
     ai rport area.
     11-002

     L i n d be rg,  Z.  Y.
     Berzinya,  A.  K.
     Audere, A.  K.

     Rizhskiy Meditsinskiy  Institut,  Riga /USSR/

     ON HEALTH  CHARACTERISTICS OF THE
     NOISE BACKGROUNDS  IN RIGA

     K  Sanitarno-Gigiyennicheskoy Kharakteristike
     Shumovogo  Fona v g.  Rige

     Medits ina

     Vol 288 No 7:134-137,  1971
The following table shows the percentage of
noise annoyance  level:
                     Percentage of Annoyance
                                                                 Source of Noise  At Work   On  Street   At  Home
I ndustri a !
Construction
Street Traffic
Truck
Streetcar
Bus
Trol ley
Trains
Aircraft
Recreation
Home Equipment
Stores
11.07
7.41
8.62
2.7
5.01
0.82
0.09
0. 11
0.3
0.01
0.0
1 .3
14
8,
29
29.
4.
5.
1.
7.
3.
0.
0.
0.
.20
.54
.48
.48
.45
.01
,39
.30
.77
,68
.02
71
11 .69
1.08
66.73
16.32
43.68
6.05
0.23
8.31
3.80
1.85
2.01
3.12
     TOTAL
                 28.82
                                      97.69
Complaints seem to increase when the noise
 level exceeds 50 dB.
     Surveys  and  measurements were  carried out
     to determine the  intensity of  noise  in Riga.
     Measurements were made on the  main
     thoroughfares  and residential  areas, and
     questionnaires  dealing with  various  aspects
     of noise were  passed out to  the  public.

     According  to the  data gathered,  motor
     vehicle  noise  ranged from 70-130 dB,
     industrial noise  45-120 dB,  and  construction
     noise  50-58  dB.

     Transport  noise seems to be  the  greatest
     offender,  commencing with aircraft noise
     (over-city flights)  100-120  dB,  trucks
     70-100 dB, street-cars 75-110  dB, buses
     60-90  dB,  trolleys 70-75 dB, motorcycles
     85-120 dB, motor  bikes 90-115  dB.  Maximum
     noise  levels were reached from 7-'0  am and
     4-5  pm.  Cobblestone streets are about 15-35
     dB noiser  than  asphalt-paved streets.

     The  degree by  which  noise penetrates  into
     the  surrounding buildings depend on  the
     sound  Insulation  of  such structures:

           -Greenery in front of  building seems
           to reduce the  noise-I eve I  by
           5-15 dB,
           -Windows  facing away from  the  street can
           eliminate the  noise  level  by 15-25 dB,
           -A good  construction of  windows and
           doors  can reduce the noise level by
           7-30 dB.

     The  survey seems  to  indicate that transport
     noise  is considered  the greatest source of
     annoyance  (67?  of cases).
11-003

Ivanov, N. I.
Skorodumov, G. Ye.

Leningrad, USSR

HYGIENIC ASSESSMENT OF THE NOISE OF HEAVY
DUTY VEHICLES

Gigyenicheskaya Otsenka Shuma Tyazhelykh
Putevykh Mash in

Gigiyena i Sanitariya

Vol  35 No  II:98-100, 1970
A hygienic assessment of the noise of heavy duty
vehicles in the USSR is presented.

The Bruel and Kjaer Sound level meter, which
makes third octave measurements, was used to
make cab and exterior (at 1,3,5 and 7 meters)
readings of several dozen tracked vehicle
types.

Diesel engine reading of 113-130 dB and work
area readings of 90-120 dB were taken.  The
frequency bands were chiefly middle and high.
Diesel cab levels up to 102-104 dB were
recorded; other cab levels ranged from 96-113
dB; all  are above the limits of the existing
standard.

Noise levels for other vehicles and their
work areas are reported and compared.  All
levels exceed the existing standards.
                                                         136

-------
                                                  DATA
                                                                                                         11-004
It is recommended that sound insulating
elements in cabs be increased by multilayer
construction of the cabs; that noise .insulation
of hoods be increased by 2-2i times; that
exhaust mufflers be installed on diesels; that
sound damping of diesel  engines be increased;
and that cabs be vibration-insulated.
11-004

CampbelI, R. A.

Veterans Administration Hospital, Miami

On:  A SURVEY OF NOISE LEVELS ON BOARD PLEASURE
     BOATS

Sound and Vibration

Vol 6 No 2:28-29, 1972
A survey of noise on board 17 pleasure boats
ranging in length from 8 to 50 ft under normal
operating conditions showed that noise levels
typically render speech communication and
radio monitoring virtually impossible and
threaten hearing loss in cases where there is
prolonged daily exposure.  There is also a
risk of accidents due to unheard spoken
commands.  There was no clear relationship
between boat size and noise levels, nor between
type of construction material  and noise levels.

Measurements were taken under four conditions:
1) quietest location on board at idling or
trolling speed; 2)  quietest location at
cruising speed (calm and open water, slowest
speed at which boat would plane or
manufacturer's recommendation);  3)  noisiest
location at cruising speed; 4) noisiest
location at maximum speed.

Noise levels ranged from 60 dBA in the front
cabin of a 36 ft cruiser at trolling speed to
104 dBA in the rear seat of a 15 ft open boat
with a 35 hp outboard at maximum speed.
(Figure 1 .)
TroMing speed
   quietest location
Cruising speed
   quietest location
   noisiest location
Maximum speed
   noisiest location
  Range
  (dBA)

60-79
                                                                                      85-104
 Typ i caI
  (dBA)

70

79
84

93
For references purposes, 70 dBA is the level
above which face to face speech communication
becomes difficult at distance of d few feet,
and 89 dBA, the  level  above which it  ts
difficult or impossible to be understood at a
distance of a few inches.  Noise levels above
89 dB were observed in 13 of the 17 boats at
maximum speed and in 8 boats at cruising
speed.  Monitoring of radio-telephones was
difficult, and was routinely attempted in only
two of the eight boats so equipped.  On These
two boats, the speaker was turned up so loud
that the  level  of radio static noise noasured
at the operators' heads was 94 dBA.  Inese two
operators, both members of the Coast Guard
Auxiliary, reported that when not on patrol
they did not ordinarily monitor their radio-
telephones.  The operators of the boats tested
were willing to accept the noise as a minor
nuisance when it was below the 85-90 dBA  level,
but higher noise  levels were complained about.

Sleep  interference  was  not mentioned  as a
problem  because  the boats were  not  slept  on
wh i Ie  unde rway.

With  the  exception of one noisier  15  f-f open
boat,  noise  levels seemed to vary  little  with
boat  length  in any of the four  types  of
measurement  conditions,  evidently  because  the
 larger engines  in  larger boats offset the
effects of greater  distances and more
intervening  partitions.  Nine boats were
fiberglass,  five  were wood, and three were
aluminum,  but construction material did not
seem  to affect noise  levels.

The following measurement conditions  were
observed:  slow  response on portable  sound
level meter; microphone  fitted with windscreen;
microphone held  at head  level of seated person
at from two  to nine  locations per  boat,
including  heads  and helmsman's  positions;  alI
boats equiped with stock engines, with mufflers
installed on three boats; all boats operated
in ordinary  fashion:  engine covers in place,
cabin hatches open, head doors closed, normal
equipment  including seat cushions and matresses
in pi ace.

Noise  levels were also measured within one  foot
of an outboard engine or inside the engine
compartment  of an inboard, these ranged from
100 to 115 dBA, thus constituting a serious
hearing  loss threat to mechanics regularly
servicing marine engines while they are running.

There are about 8,000,000 power pleasure  boats
in the U.S.  Even if the risk of hearing  loss
to the operators  is ignored, the risks of  poor
speech communication (loss of a total boat ana
its occupants because of missed voice commands
                                                    137

-------
11-005
                                                       DATA
    or warnings) is not acceptable.   The range of
    cruising speed  noise levels  found in these
    boa-'-s is similar to that found  in airline  jet
    aircraft cockpits (81-96 dBA).   Standards
    suggested for cockpit noise  (by  R.  B.  Stone,
    Aerospace Medicine 40,989-993,SEPT,  1969)  are
    90 dBA maximum  and 85 dBA for normal  cruising;
    these would  guard against hearing loss  and
    insure close-range speech communication,
    although with difficulty.  Such  standards  are
    directly applicable to  power boats.
    11-005

    Oesterre'chischer Arbeitsring  fuer
    Laermbekaemptung, Vienna /Austria/

    1012  v'iema,  Ctubenring  1, Austria

    LESS  NOISY  CONSTRUCTION OPERATION

    Laermarmer  Baubetrieb

    Ossterreichischer Arbeitsring  fuer
    Laermbekaempfung  Industrie-RichtIinie

    2nd ed.,  Vienna, No.  111, APR  1970,  11p.
                                            Maintenance is  an  important factor of noise
                                            abatement.   All  plates  should always be well
                                            fastened  and the sound  dampers and gears always
                                            clean.   Correct lubrication preserves machinery
                                            and helps to reduce noise.   Bi-annually, all
                                            machinery should be inspected and overhauled
                                            to insure that  all  of  the noise-preventive
                                            measures  are operating  properly.

                                            For huge  equipment,  tents and shields are
                                            recommended as  noise reducing devices.
                                            Shields,  of course,  can  dampen the noise only
                                            against one direction.   In  order  to be
                                            effective they  must  be  at least 3x3 sq.  m
                                            and consist of  materials  such as  iron sheet
                                            with  5-8  cm fiber wool  behind perforated
                                            sheet metal;  such outfitting  can  reduce the
                                            noise level  by  5 dB.

                                            Tents consisting of  plastic mats  with mineral
                                            fiber filling or foam filling can reduce the
                                            noise level  by  10 dB.  Huts of light wood
                                            construction  can achieve  noise reduction of
                                            20  dB.

                                            In  planning  a construction  operation  all of
                                            these measures must  be taken  into consideration
                                            by  the firm  and  the  architect involved  in  order
                                            to  avoid  any  unnecessary  and  undesirable noise
                                            levels and  conditions.
    It  is  the  task  of  technology to offer  unlimited
    safe working  conditions to the worker  in all
    types  of operations.

    The  best means  for noise  reduction  is  to take
    measures right  at  the  source, by  means of
    screening, encasing, etc.  Noise  levels are
    listed for various construction machines
    measured a* 1 meter, ranging from 75-85 dBA
    for  a  socket  wrench to 120-125 dBA  for a
    compressed air  pile driver.  At 7 meters the
    noise  level  should be  15  db  lower.

    Since  noise levels are much more  disturbing
    during the night,  construction work should  be
    avoided and if  it  is absolutely necessary,  it
    should be  executed only with quieter equipment.

    These  are  some  of  the  recommended noise  levels:
        Area
    Quiet area
      (residential,
    Downtown area
    Industrial area
     Permissible Noise Levels
       Day (dBA)  Night (dBA)
vi Ilage)
50
60
65
40
50
55
    Noise reduction methods are given for
    particular individual  pieces of equipment.
    For instance, whenever possible, combustion
    engines should be replaced by electrical
    motors.  For all  equipment such as concrete
    mixers, hammers,  etc.  the same is recommended.
    All internal combustion engines may be
    equipped with special  effective sound dampers
    for the exhaust area,  as well as the induction
    s ide.
                                            11-006

                                            Young,  J.  R.

                                            Stanford  Research  Institute,
                                            Menlo Park,  CA

                                            Sensory Sciences Research  Div.,  Zip  94025

                                            ATTENUATION  OF  AIRCRAFT  NOISE  BY WOOD-SIDED
                                            AND  BRICK-VENEERED FRAME HOUSES

                                            Springfield,  VA, NTIS, N70-32694,  1970,  37p.
                                            HC:  $3.00  MF: 95 cents
Attenuation characteristics of a typical brick
veneer house and a typical  wood-sided house
were measured for aircraft noise during the
course of a NASA study of the subjective
evaluation of aircraft noises.  The differen-
types of aircraft, a four engine propel  lor-
driven Lockheed 1049G, and a four engine
turbofan jet CV-880 were used as the noise
sources.  They flew runs directly over the
houses on straight and level flights at
altitudes of 1200 and 2000 feet, respectively.
It was found that in any one-third octave
band of frequencies, the maximum noise outdoors
did not occur at exactly the same time as the
maximum level indoors.  Attenuation could thus
be defined ir. several different ways.  The
best descripfor of tie effect of the test
house structure on the aircraft noise,
measured inside the -louse, was found to be
                                                        138

-------
                                                   DATA
                                                                                                         11-007
house attenuation defined on a 1/3 octave
band basis by the difference between an
outdoor band maximum and an indoor band
maximum, without regard for when these
maxima occur.  Eight indoor locations, two
for each of four rooms, were used.
Measurements were collated so that four
estimates of attenuation were available for
each room.  From these estimates, average
attenuations in each band were calculated, and
these average values were used in turn to
plot house and room attenuation characteristics.

The two one story houses were tested with
windows and doors closed and with completely
furnished rooms—carpets, drapes, and the
normal complement of tables, chairs, etc.

The  following table shows samples of typical
results of attenuation for the houses  (peak
measure statistics, data from four flybys):
Place
BRICK VENEER
Dining room
Living room
Bedroom No.  1
Bedroom No. 2

WOOD-SIDED
Dining room
Living room
Bedroom No.  1
Bedroom No. 2
     A-weighted level
Avg., dBA  Std.  dev., dBA
   22.6
   20.9
   27.1
   25.6
   20.7
   19. 1
   24.3
   17.3
3.0
4.5
2.6
1.1
0.7
1 .1
1 .9
2.6
Results evaluated  in PNdB were within  1-2 dB of
the  results expressed  in dBA.  The house
attenuation numbers obtained  in this study
correlated within  2 dB of those given  in SAE
document AIR  1081  (1969) for  houses  in Boston,
New  York,  Los Angeles, and Miami, with various
numbers of rooms.

A measure of  how useful the attenuation data
were  for predicting indoor noise  levels was
made  by weighting  outdoor data with  the
attenuation characteristic for each  room to
compute the estimated  indoor  levels.  A
comparison between the estimated  and actual
values showed that the attenuation data are
useful for indoor  noise prediction purposes.
 11-007

 Greater London Council /England/

 The County Hall, London SEI

 INDUSTRIAL NOISE:  REFUSE TREATMENT PLANT

 Urban Design Bulletin (London)

No 2, 1970
                                       The Greater London CounciI wi I I use a  standard
                                       method of calculating  probable  communify
                                       annoyance caused  by  industrial  noise  in
                                       planning a series of government-owned
                                       industrial plants.   In the course of  its  design
                                       work on refuse  treatment  plants,  it has
                                       published design  guidelines  illustrating  how  a
                                       hypothetical  plant might  be  planned (Figure  1).
                                        fit 1 S>Nplino'*nlneu»fllKInpl«l
The standard method used  is British Standard
BS 4142:1967, upon wnich the  International
Standards Organization  (ISO)  draft Resolution
1996  is closely patterned.  This standard
states that complaints may arise if a new
noise source is introduced to an area,
resulting in a rise in excess of 10 dBA over
the existing background noise levels,
measured just outside the nearest residential
bui Idings.  However, in sensitive areas a
possible increase of 5 dBA should be viewed
with caution, because of other possible
insidious rises in background noise levels.

In calculating the noise of a proposed plant,
the level  at the site boundary must be adjusted
for duration, presence of pure tones, and
periods of louder or more disturbing noise.
The adjusted caleu I a fed level  is then compared
to the background level  to judge if the plant
will  be suitable.   If background levels can not
be measured,  a basic criterion of 50 dBA may be
used,  which is then corrected according to the
type of district (ranging from purely
residential  to industrial).

In planning the refuse treatment plant,
designers relied on noise survey data from
three existing plants and one French plant,
as well  as information derived from
manufacturers (see figure 2).

They then used a variety of methods to plan a
plant that would meet BS 4142.

First, noisy processes are concentrated within
a  building with walls as imperforate as
possible and  with  adequate acoustic insulation.
                                                    139

-------
11-008
                                                        DATA
     Windows  are minimal  in area, on the side of the
     building away from nearby noise-sensitive
     areas  only, and sealed.   Second, noisy processes
     are located within the site in such a way as to
     minimize their noise emissions in a particular
     direction,  in this case, in the direction of a
     hospital to the southeast.   Other buildings act
     as  shields, and one retaining wall and earth
     bank is  provided to shield the noise from
     extensive unloading activity by dump trucks.
C - Castle Brwnwich Refuse Disposal Workt.

D - Direcl Incineralion Plant Derby

P - Usine d'lssy-lef-MouhneauK. Pans

M - Manufacturers Information

F - Folkstone Road Refuse Pulveriser London. E 6
•Plant Noise LevHi
Fin 2.


I External Measurements
Flint
1 Refuse vehicle starting
2 Refuse vehicle on level
ground, steady speed
3 Refuse vehicle on slope,
steady speed
4 Forced draught fan
5 Induced draught fan
6 Cooling tower
7 Cooling tower
8. Cooling tower
9 General plant noise'
(mosily de-duster)
10 General plant rio.se1
11 General plant none '
12 General plant noise '
13 Residuals
(conveyor and chute)
14Sevefalveh.de*
discharging
15 Magnetic separators
+ clinker & fly
ash conveyor
16 Pulveriser only
17 Vibraiory feeder
18 Pulverizer with
vibratory feeder in
Location
at 7 5 metres
at 7 5 metres
at 7 5 metre*
at 3 metre,
at 3 metres
at 30 metres facing
louvres
at 130 metres facing
louvres
at 270 metres facing
'ouvret
at 110 metres from
wall
at 300 metres from
plant
al 50 metres from
plant
at 1 00 metres appro x
at 10 metr«
entrance (outside
reception had
at 10 metres
at 10 metres
at ID metres
at 10 metres
Noise itvet
84dB(A)
80 dBIA)
83dB(AI
76dB(A)
71 dBIA)
69dB(A)
60 dB.A)
54 dB(A)
52-53 dB(A)
45-46 dBIA)
(Hum of de -duster
Clearly audible)
57 dB(A)
S3 dBIA)
75dB(Al
62 dB(A)
B2dB(A)
70dB(A)
81-82 dB(A|
79-83 dB(A>
S/»
C
C
C8.D
C
C
M
M
M
C
C
D
P
0
C
P
F
F
F
b Internal Plant Noi»r
1 Metal press
2 Cardboard press
3 Induced draught fan in
reverberant conditions
4 Collection vehicle,
tipping
5 Water pump, reverberant
c Internal Environmental
fttdbffwurirjiou.ioutt.
1 3 vehicles discharging
2 One conveyor plus
3 Conveyor
4 General plant noise *
5 General plant noise '
6 General plant noise '
7 Refuse feed chute
8 4 bo.ien in use
9 Turbines
at 3 metres
M 3 metre*
at 3 metres
at 3 metres appro*
at 3 metres
Noise Levels
Locrton
Reception hall
on 'bridge'
In elevator room
on 'bridge'
Inside separation
Incinerat.onr-om
(by control desk)
,±r mcineri"'on
.ns,de bo.ler house
Inside turbine hall
84-86 dB(A)
(mostly clangs)
86- 88 dBIA)
91 dB(A)
90-92 dBIA)
91 dB(A|

Notx level
88-91 dBIA)
87dB(A)
79 dBIA)
89-91 d8{A)
7B-82dS(A)
BOdB(A)
IQOdB(A)
81 dB(A)
88 dBIA)
C
C&D
0
D
D

&(*
C
C
C
C
c
D
0
P
P
                                                                  11-008

                                                                  Schirmer, W.
                                                                  Biehn, K.

                                                                  VEB RFT Messelektronik, Dresden  /East Germany/

                                                                  NOISE SITUATION  IN TYPEWRITER  TECHNIQUE

                                                                  Zur Laermsituation  in der  Schreibmaschinen-
                                                                  techni k

                                                                  Fei ngeraetetechni k

                                                                  Vol 18 No 11:510-516, 1969
                                                                  Methods used by the office-equipment industry
                                                                  of the German Democratic  Republic to reduce
                                                                  noise-levels are discussed.   Numerous noise-
                                                                  measurements were  carried out on  typewriters.
                                                                  For this purpose,  a cabin 3.5 x 4.5 m.  and
                                                                  about 2.5 meters high was employed and
                                                                  measurements were  taken  1 meter from the
                                                                  noise source by means of  the precision impulse-
                                                                  audiometers  fype PSI 101  and PS I  202 installed
                                                                  by VEB RFT Measuring Electronics, Dresden.

                                                                  The machines were  placed  on  a 650 mm high table
                                                                  covered with a plate of  500  x 500 x 20 mm size
                                                                  consisting o* 200  mm thick foam and 15 mm thick
                                                                  felt materials.  By this  means, only the
                                                                  typewriter noise  is captured.  The distance
                                                                  between microphone and  the source is 4 m.

                                                                  The type of  stroke and  the speed play an
                                                                  important role  in  the measurement.  The range
                                                                  of the speed and the troke stresses the
                                                                  difference  in typing.   A normal text can vary
                                                                  up to 6 dB.

                                                                  It  is thus  recommended  that the same typist  be
                                                                  used  in determining the noise-I eve I
                                                                  measurements.

                                                                  It was determined  that  for a significant
                                                                  difference of about 2  dB between 2 mean values,
                                                                  10  individual measurements are required to
                                                                  achieve about a  95% accuracy.

                                                                  The main source  of typing noise  is the  impact of
                                                                  the type bar on  the  recoi I ring and the type
                                                                  impact on writing-roll.  Speed plays an
                                                                  important  role  in  the  above.

                                                                  Measures taken  to  combat this type of noise  are
                                                                  to compress  felt material with lead around the
                                                                  recoiI ri ng.
                                                          140

-------
                                                   DATA
                                                                                                         11-009
The noise caused by manipulating the space-bar
can range from 10-25 dB:  in portable
typewriters, about 20 dB;  office typewriters,
25 dB, and electric typewriters, about 20 dB.

The next source is shifting, which again can
range from 10-20 dB.  Investigations were made
on portable-typewriters with plastic casing and
electric typewriters with metal casing.  The
parts of the absorbers consist of Moos-rubber
layers.

The movable parts of the machine should be
made of  lighter material instead of heavy ones.
Damping by means of plastic and metal casing
seems so far to be most useful.

         Impulse-Noise Measurements
Type of
Mach i ne
Portable
Typewri ter
Office
Typewriter
Range of Noise
Level
78 	 83 dBAI
87 	 89 dBAI

Mean Va I ue
83 dBAI
88 dBAI

         Impulse-Noise Measurements
Function

Typ i ng Noise
Space Bar
Sh i fti ng
Carri age
Hoist
Idling Noi se
Standard
Typewri ter
82 dBAI
60 dBAI
60 dBAI
60 dBAI
Electric
Typewriter
85 dBAI
67 dBAI
62 dBAI
77 dBAI
60 dBAI
            35 dBAI
 11-009

 Vargov i ck , R. J .

 Ford Motor Co., Dearborn, Ml

 P.O. Box 2053-K237.0 Zip. 48121

 NOISE SOURCE DEFINITION - EXTERIOR PASSENGER
 VEHICLE NOISE

 New York, Society of Automotive Engineers,
 1972, 8 p.
Recent studies have  indicated that the
passenger vehicle  is a major contributor to the
annoyance of traffic noise.  A test series was
conducted at the Ford Michigan Proving Grounds
on a concrete surface.  The purpose of the
test program was to determine the contribution
of each car noise source.  A 1970 high and low
power sedan and a high and low-power sporty
compact were used in the test.
                                       The  results of the test show that,  for wide open
                                       throttle conditions, engine/exhaust noise
                                       predominates, being  14 dBA above the other
                                       noise sources.  Adding another muffler  in
                                       series  resulted in a sound level redudion of
                                       6  dBA.  The engine contributes about 50* of the
                                       total noise below 500 Hz.  Tire/road noise  is
                                       the  major source above 500 Hz.  The contributor
                                       of the  cooling fan to the total exterior vehicle
                                       noise at cruise is negligibte at alI
                                       frequencies.  This conclusion was true for all
                                       engine/vehicle combinations fesfed except the
                                        low  power sedan at 65 mph.  The tires used  in
                                       this study we re typical, original equipment,
                                       bias-belted tires.

                                       The  most immediate reduction  in  levels is
                                       required for  trucks, with a reduction of exhaust-
                                       noise as the  first goal.  A reduction of 16 cB
                                       corresponds to eliminating 97% of the noise
                                       energy  emitted.  Additional data are needed to
                                       determine the true variation of tire/roadway
                                       noise with speed and thus formulate more
                                       accurately the noise generation model for this
                                       source  of noi se.
11-010

Wojtowicz, R.

Zaklad Projektowania Budynkow Sluzby
Zdrowia, Politechnika, Gdansk /Poland/

Poznan

THE PROBLEM OF LOW INTENSITY IMPULSE NOISES
IN HOSPITALS

Zagadnienie halasow  impulsowych niskiej
intensywnosci w szpitaiu

Przeglad Lekarski

Vol 25 No 2 255-258,  1969
                                        An  investigation  was  carried  out  in  Poland en
                                        the.major  acoustical  problem  of hospitals and
                                        their  construction.   Part  of  its  was  based
                                        on  measurements and on  the replies to a
                                        questionnaire  sent to 465  physicians  engaged
                                        in  25  various  departments  of  22 hospitals.
                                        Of  the inquiries, 47.5^ involved  clinical
                                        hospitals,  23.5%  regional  and the rest
                                        municipal  hospitals.  The  time of this
                                        particular survey was the  fall-winter
                                        season when  a I I the windows had to be
                                        closed.

                                        Many noise sources  (38)  were  investigated and
                                        some of  them compiled into charts on  noise
                                        impulses.
                                                    141

-------
11-011
                                                       DATA
     Noise Source
                                 Levels  (dBA)
Hospital
                                                                               Freeway
           Distance
           (feet)
     1.  Trolley-street car
     2.  rush hour
     3.  street noise             50-80
     "».  slamming of doors
     5.  walking in  heavy  boots
     6.  ambulance sirens

     7.  squeaking floor          50-60
     8.  visiting hour

     Noise Source                Level  (dBA)

     1.  Radio & TV
     2.  Refuse removal            up  to 90
     3.  School
     4.  Recreational  areas

     5.  Cleaning
     6.  Dormitory (for nurses
          & medics)              60-85
     1.  Calls in the ha I Is

     All  the studies were based on  the Chocholle
     criterion.  Hospitals are  built inadequately
     and require much better insulation and
     architectural  design, since what is considered
     to  be tolerable noise level for a healthy
     individual is  unbearable and damaging for  a
     patient.  The  study  showed that impulse  noise
     levels in the  hospitals exceeded norm
     PN-63/B-02151.
                                    Noise Level,
                                    dBA (windows
                                    open)
Queen of
Angels (7th
floor)
Deaconess
(7th floor)
S.F. County
(4th floor)
Loretto
St. Lukes
(2nd floor)
Hoilywood
(11,000-
11,600
veh icles/hr)

3rd  Ave
(1500
veh icles/hr)

Bayshore
(5,000-
13,000
veh icles/hr)

Congress
(5,000-
8,000
veh icles/hr)

Congress
(8,000-
10,000
veh icles/hr)
                            400
                            400
                            300
                            200
                            150
                                      67*
                                      55
                                      60
                                      60
                                      61
* hospital on hill above freeway

For purposes of comparison, data on  two air
conditioned buildings with sealed  windows  are:
48 dBA at 300 feet (6th floor); 43 dBA at  150
feet  (2nd floor).  With the windows  open,  the
noise  levels were  in  the 60 dBA range; this  is
5-7 dBA  higher than what would be  expected for
residential under  similar conditions.  The
possible reasons for  the higher  levels  in
hospitals are first,  that these particular
freeways may have  had a higher volume of
truck  traffic; second, that there  was an
unobstructed sound path; or third, that
background noise generated  inside  the hospital
was not  taken  into account.
      11-01 1

      Lane,  S.  R.

      California Univ.,  Los  Angeles

      School  of Arch,  and Urban  Planning,  Zip  90024

      On:   NOISE INSIDE  HOSPITALS FROM FREEWAYS

      In:   Lane, S,  Freeway  and  Highway Noises:  an
      Information Base for Urban Development Decisions

      Springfield,  VA, NTIS, PB  204434, 1971,  90p.
      (p.  36-38)
      Data were obtained on noise levels in Los
      Angeles hospital rooms, most of which were
      upper rooms facing a freeway and with a direct
      view of the freeway.  The ground distances from
      the hospitals to the freeways ranged from 140-
      400 feet.
 12-001

 Rylander, R.

 National  Inst. For Public Health, Stockholm
 /Sweden/

 Dept. of Environmental  Hygiene,
 10401 Stockholm 60

 SONIC BOOM EXPOSURE EFFECTS 1.1: INTRODUCTION

 Journal of Sound and Vibration

 Vol 20 No 4:477-484, 1972
 The workshop on sonic boom exposure effects
 was convened at Saltsjobaden, Sweden, SEPT
 7-9,  1971.
                                                          142

-------
                                                                                                         12-002
                                                 GENERAL
The sonic boom can affect the health of man
directly or indirectly.  The prospects are
relatively bright for technical  developements
which will limit the exposure to acceptable
levels, and which will allow the establishment
of an exposure control system.  Considerable
research efforts have been and are being spent
to understand the effects of exposure to sonic
booms.  The workshop was held in the
knowledge that the sonic boom is a basic type
of acoustic stimulus affecting structures,
animals and humans.  Consequently the results
achieved from the workshop on sonic booms
should also be applicable to a range of
industrial and other environments where sudden
bursts of noise are present.
The distinction between performance tests and
development tests must be emphasized.  A
performance test is carried out to determine
whether or not a product in development has
met its acoustical  objectives or specifications.
A development test is conducted by engineering
personnel  to guide the design of the noise
control features that must be incorporated
into the new product.

Noise control techniques can be applied to
almost any product, but not without an
economic penalty.  If noise control  is an
afterthought, the economic penalty is
frequently excessive.  Early application
of noise control in a project may minimize
cost for the quietizing features.  The
conclusion is drawn that technological
factors are no  longer placing a  limit on
the control of product noise.
 12-002

 Lang, W. W.

 IBM Acoustics  Lab., Poughkeepsie, NY

 P. 0. Box 390, Building 704,
 Zip 12602

 PRODUCT NOISE  AND  ITS CONTROL

 At: American Association for the Advancement of
 Science, 138th Meeting, Philadelphia, DEC 29,
 1971

 Poughkeepsie,  IBM Acoustics Lab., 1971,  14 p.
The methods used  in a product noise control
program are discussed.  The program stresses:
1) the right tools to do the job,
2) the appropriate skills of trained personnel,
3) the motivation to develop a quietized
product and, 4) an early start on the
engineering aspects of noise control.

The development of a quietized product requires
the skills of a team of noise control engineers,
an engineering specialty requiring both formal
training and practical experience.

The motivation to develop a quietized product
is embodied in the acoustical  objectives and
specifications for the product.   Experience has
shown that without quantitative criteria to
guide the development of a new product, the
desired result is seldom achieved.

The fourth ingredient of a successful program
is an early start on the engineering aspects
of noise control.  To achieve the most effective
noise reduction at minimum cost, noise control
features must be carefully planned and
incorporated into the design of  the new
product as early as possible.   An evaluation of
the new product should be made by skilled
noise control  engineers.
 12-003

 THE  DIN OVER MUFFLING  NOISE

 Business Week

 APR  8,  1972, p.  32
 Under  force of  the Occupational Safety and
 Health Act, standards  have already  been set
 which  limit the amount of noise to  which
 workers are exposed.   The field of  product
 design, except  for airplanes, however, is
 totally void of any such standards, and
 as a result it  is the  consumer who  pays
 the price for noisy equipment.  In  its
 report on noise under  the Clean Air Act of
 1970, the EPA pinpointed construction
 equipment, trucks, motorcycles and  off-
 the-road vehicles for  chief focus.  State
 and city regulation against noise have
 appeared, and some are getting tougher.
 California, for instance, will drop its 88
 dBA limit on cars and trucks to 83  dBA
 by 1975 (measured at 50 feet).  Most
 manufacturers favor EPA action to keep an
 unwieldy patch work of local regulations
 from spreading.  The cost of noise
 abatement and control will not be cheap.
 With all  the muffling and vibration damping
 necessary for a 10 dB decrease in noise, one
 manufacturer estimates that the price of a
 $5,000 diesel  would go up $1500.  Another
 estimate is that it will  cost an additional
 $30-$50 per car and up to $125 per  truck for
 auto makers to meet California's 1973  limits
 of 86 dBA.

 One aspect of more Federal legislation also
 bothers manufacturers.  The auto makers, in
 particular, are concerned that the  government
 may not coordinate its demands on noise, air
 pollution, and safety.  For example, catalytic
 air cleaning devices may compete with sound
 deadners  for limited space in cars.
                                                    143

-------
12-004
                                                      GENERAL
     A  second  noise  source,  tires,  becomes  the
     dominant  source above approximately  35 mpn,
     and  noise regulations may  eventually focus
     on  it.
    12-004

    Toole, F.E.
    Brammer, A.J.

    National Research Council  of Canada,
    Ottawa /Ontario/

    Div. of Physics, Montreal  Road, Ottawa 7

    THE "NOISE THERMOMETER":  A LARGE-DISPLAY SOUND
    LEVEL METER

    At:  Acoustical Society of America, 82nd Meeting,
    Denver, OCT 22, 1971

    Ottawa, National Research  Council, 197?, 10 p.
    A large-display sound level meter to be used for
    educating the public as an aid to enforcing
    noise laws is described.  A prototype of such
    a display has been developed by the National
    Research CounciI  (NRC) of Canada and tested on
    the NRC's grounds and by the city of Edmonton,
    Alberta.
    Although much anti-noise legislation is based on
    measurements in dBA, the average citizen often
    lacks even an approximate subjective
    interpretation of quantitative limits expressed
    in dBA.

    The complete display is called a "noise
    thermometer" and consists of an 8 ft tall  display
    sign and a remote microphone unit.  The acoustic
    input is converted into a column of lights that
    looks similar to the column of mercury in a
    thermometer.  The display registers from 70-100
    dBA in 2 dBA steps.  As the sound level rises
    as a vehicle approaches the microphone, the
    display  develops in 2 dBA increments.  The
    maximum  level  is sensed and the full display  is
    retained for approximately 4 seconds to enable
    the driver to observe the  level produced by his
    vehicle   (Figure 1).

    Silhouettes attached beside the column of  lights
    indicate maximum levels permitted by state or
    local law for various classes of vehicle.
    However, if the law is complex (for example,
    specifying different levels at different
    speeds), use of the silhouettes is not
    advisable.
display; however, the meter can be used as a
check on the calibration of the display.  The
circuitry of the display is such that the onset
time is similar to that of a sound level meter
on "fast" response.  But the response to
transient signals is slightly faster than a
sound level meter on "fast," resulting  in an
exagerated reading for highly impulsive sounds
such as those generated by many motorcycles and
some unmuffled trucks.  This error is in a
desirable direction and should not be corrected.
The display will operate with an accuracy of ±
2 dBA within a temperature range of 45-90
degrees F.

The "noise thermometer" was used during the
summers of 1969 and 1970 within the NRC grounds
in Ottawa.  Many potential offenders of the
Ottawa City By-Law were observed travelling to
the test site to check out their vehicles, and
some motorcyclists even performed modifications
on the spot.

In Edmonton, Alberta, the display has been used
over 1 million times in five months to  publicize
the city's new anti-noise legislation.  During
the first six weeks of the campaign, the site
of the "noise thermometer" was changed
frequently, with the news media publicizing each
change and restating the purpose for the device.
One source of concern had been that a possible
slowing-up of traffic in the vicinity of the
"noise thermometer" would lead to congestion and
an unsafe  interruption in the traffic flow.
However, although the device attracted  increased
traffic, no serious congestion has been
reported.
                                     Display Cleared
                                     ""and Ready for
                                     Hext Vehicle
    The microphone is situated at a distance from
    the traffic that is relevant to the local noise
    regulation.  Within the microphone housing is
    a sound level meter (Bruel and Kj'aer model 2205)
    that functions only as a microphone and
    amplifier for the circuitry housed within the
                                                        144

-------
                                                                                                            12-005
                                                   GENERAL
12-005

Zimmerman, '-1. 0,

THE POLLUTION PANIC HITS  HOME

Machine Design

Vol 43 No 24:19-21, 1971
Environmental noise has  been  doubling  ever/
10 years and the noise  levels  in  domestic
quarters are beginning  to  approach  those
in factories.  Kitchen  and  household
appliances contribute to the  moooi  and
outdoor noise environment  of  the  home.
Makers of household appliances  are  already
working to quiet such noisy products as
blenders, exhaust  fans,  mixers, garbage
disposers, and dishwashers.

Methods for controlling  Hie noise levels
of such appliances  include  yioration-damp ing
mounts, insulating  fiberglass  shields, lower
motor speeds, and  the relocation  of noisy
components within  machinen/.   The use of
rotary heat excnangers  in  ->•   -,ond ' f loners
may  i ncrease.

Strict noise ordinances  exist  in  Memphis and
Coral Gables.  Chicago  set  a  maximum permissible
noise level for new outdoor power equipment
•_cid ir the city at 74  dBA.
A paper on Pi-ob'ems  of  Noise Meas ire ,~ if"
in Construction  Machinery  wa.j pr?<'~ *~ : oy
Dr. K. S/ynaniki.  The  discus  . ,  wr,,^  <.,!
clearly Pressed  uaust'-y's  rr  ,
lower the noise  l-'-yc-ls  ,•  •    i r , , „•

During the conference,  Bruel  and  Kjae'' of
Denmark presented  an exh'bit or  all  rr.ei;
I'-easut i r j cqu i pme'i r. ar c  the G • 1 i ' ; V • ' A i-
of Sweden d i sp I av ^ i  rhei r  aeon - r i •- ; •  t i
vibration insulari-,' mater   ,1-
Bolt, Beranek,  and  Newman,  Inc.
Cambridge,  MA
 12-006

 Raj chert,  W.

 Warsaw,  Ul.  Lwowska K

 CONFERENCE ON  THE ThE'T OF NOISE ABATEMENT

 Konferencja  nt.  Zw,- I <.^ en I a Halasu

 Problemy Rozwoju Budowrii; fwa

 Vol 5 No 6.49-50,  19AO
A conference  on  No'sc  "c;  France,  U.  S., Sweden,
Hungary and  Italv.    p total,  there were over
300 Durtir.p-jnK  •'-': f=^-nting  the industrial,
science and res'V^r'i  rields.
The  role  of  the  ncise r'vi"*"•''  ,onsult3r
obviously  must fe th^t of a probU-
solver, but  it   i ,o ",•_',t h^ fr^t  of
counselor, educaf^jr and advisor.   He
must see  to  it that noise control  efforts
will be conauc t ed toward reaI i -^ i;
goals thar are compatible wi+h  ^he  law
and wilh  tne on-going objectives of the
client.   A great advantage ot  the noise
control consultant is Ms exper  ^neo
an*"-  his f r oecorn  to recorin^i (l a  h^i , ^ >
o^ a I f" r nat, ve sc I ut i ^. i .

There are  not cn_unn  nc i ^e cci'~iio'
e n g i n ee rs  I o s c i vc  e x i -; ^ i' i g i n d ,  ' * i -i
problems,  eHtv,_r  ^-, > :.dep£ ^'{^n~
consu'Tartj  o1 as adu.'i^ •  iu  M  ju_- :   ' -. i
staff,  so  it  wih  fji   lo iruu^Tiy  1,1  -DC
end to  solve n\.,_-t problem? v» i4 %  ,'r'oLse
pe rsci'iio ; .   I' t r-r* i r i - r i n,
consultant can pro^ioo sclu'it i,    i:  t  ^
most i iTiiTieu i ate probleri'S ufuj ;t  rne sane
time use  these problems as nf3r,:,  tor
educjriuy  I he clienl':  sTcfi.

The rrost  progress is  made when  a
consultant,  tarriiliar  wirh noise  cent.-'
materials, methods, and mtatij,  vV'fks
intimately with  mcrr.be rs "it the  s M ei^ ' >
                                                     145

-------
12-008


                                                      GENERAL
     staff,  who know the requirements  imposed
     by production and process  control.   Only
     then can  solutions be expected  to be
     compatible with space,  costs, operating
     personnel, and long-range  production goals.

     Often an  independent voice is needed to
     aid in  deciding internal questions  to
     support a position in a court of  law.  The
     consultant can serve here  as an unbiased
     expert.
     12-008

     THE  GREAT  OFFENSIVE OF THE  "NOISE  SPIES"

     Grossoffensive  der  Laermspione

     Die  Presse

     Vienna,  SEPT 18,  1971
     An  article  reports on  an  international
     noise  conference  of  100 noise  experts,
     held  in  Vienna.   The Congress  was
     promoted by the  International  Standards
     Organization and  organized  by  the
     Austrian Standards  Institute with  the
     assistance  of Professor Bruckmayer of  the
     Technical University of Graz and Dr.
     Judith Lang of the Noise  Control  Institute
     of  the Technical  Industrial Museum of
     Vienna.

     The Congress plans to  produce  a noise
     catalogue and set bases for legal
     measures which should  effectively  protect
     individuals from  noise-induced health
     hazards. The main chapter  shall contain
     thorough coverage of aviation  noise, as
     well  as  noise from heating  and refrigeration
     equipment,  and include protective  devices.
     It  shall also deal with the necessary
     guidelines  on all noise sources.

     As  a  first  step toward effective  noise
     protection  the experts plan to carry
     out more precise  measurements  and  set  up
     noise  level survey charts.

     The most important task of  the Congress
     is  to  formulate  International  Norms.
                                                         146

-------
                               SUBJECT  INDEX
Abatement Devices                        02-010
                                         07-007
                                         10-010
                                         12-006

Acoustic Consultants                 '    12-007

Acoustic Damping                         00-033
                                         01-013
                                         01-023
                                         05-002
                                         10-001

Acoustic Dampers                         01-021
                                         01-025
                                         11-005

Acoustic Engineering                     12-002
                                         12-007

Acoustic Stimuli                         12-001

Acoustic Trauma                          02-002
                                         02-006

Adaptation                               02-005
                                         03-017

Agricultural Equipment                   00-020

Ai r Bags                                 00-025

Air Conditioners                         06-006
                                         07-017

Aircraft                                 00-016
                                         00-035
                                         02-012
                                         04-003
                                         07-001
                                         07-012
                                         07-015
                                         10-004

Ai rcraft Noise                           00-007
                                         00-008
                                         00-013
                                         00-024
                                         01-004
                                         01-017
                                         01-018
                                         03-001
                                         03-009
                                         03-02?
                                         04-005
                                         05-003
                                         06-007
                                    147

-------
Aircraft Noise (Continued)               06-011
                                         07-002
                                         07-004
                                         08-005
                                         08-007
                                         10-001
                                         10-002
                                         10-006
                                         10-008
                                         10-009

Airport Noise                            00-007
                                         02-012
                                         03-015
                                         07-004
                                         07-008
                                         07-015
                                         08-001
                                         10-002
                                         11-001

Airport Siting                           10-001
                                         10-009

Amplified Music                          02-008

Animals, Effects On                      00-026
                                         02-016
                                         03-003

Annoyance                                00-031
                                         02-015
                                         03-003
                                         03-006
                                         03-012
                                         03-013
                                         03-014
                                         03-015
                                         03-016
                                         06-009
                                         06-013
                                         11-002

Appliances                               12-005

Architectural Design                     03-019
                                         05-002
                                         05-003
                                         07-007

Arousal Response                         02-007

Astronauts                               03-010

Attenuation                              06-008
                                         06-012
                                         11-006
                                    148

-------
Audiological  Investigations              03-001

Auditory Awakening Threshold             02-007
                                         03-007
                                         03-010
                                         03-011

Auditory Preception                      03-006

Austria
Automobi les                              01-010
                                         07-012
                                         07-013
                                         11-009

Awakening Effects                        02-007

Background Noise                         02-017

Barriers                                 06-010
                                         07-010
                                         07-011
                                         07-012

Boats                                    00-018
                                         00-019
                                         11-004

Bui Idi ng Codes                           00-013
                                         08-007

Buses                                    01-013
                                         10-010

Canada                                   01-008
                                         01-014
                                         01-015
                                         12-004

Central  Nervous System                   03-018
                                         03-023

Chicago                                  01-025
                                         08-011
                                         08-012
                                         12-005

Chi Idren                                 00-006
                                         00-022

City Planning                            00-015
                                         01-027
                                         06-004
                                         07-001
                                         07-006
                                         07-016
                                         07-018

                                    149

-------
Community Noise                          00-008
                                         00-027
                                         01-018
                                         01-022
                                         02-009
                                         03-002
                                         03-015
                                         06-003
                                         06-009
                                         07-009
                                         08-001
                                         08-009
                                         10-002
                                         10-007

Compressors                              01-022

Computer Printers                        01-016

Conoids                                  01-007

Construction Equipment                   00-002
                                         00-003
                                         00-004
                                         00-032
                                         01-001
                                         01-005
                                         04-001
                                         06-005
                                         11-005

Construction Material                    00-014

Construction Noise                       00-012
                                         01-005
                                         01-025
                                         04-001

Continuous Noise                         03-018

Cost-Benefits                            00-004
                                         00-023
                                         00-036
                                         01-027

Cost Penalty                             00-001
                                         00-002
                                         00-003

Costs                                    00-017
                                         00-020
                                         00-030
                                         00-032
                                         00-033
                                         00-035
                                         01-013
                                         04-002
                                     150

-------
Costs (Continued)                        04-001
                                         05-002
                                         07-002
                                         07-010
                                         10-004
                                         12-003

Court Claims                             08-006

Criteria                                 02-009
                                         06-009
                                         06-013
                                         08-008
                                         11-004
                                         11-005
                                         11-007

Damage Risk Criteria                     02-006
                                         03-021
                                         08-003

Diesel Engines                           01-013
                                         11-003

Diesel Locomotives                       01-011

Discotheques                             02-002

Economics                                00-001
                                         00-002
                                         00-003
                                         00-004
                                         00-023
                                         01-027
                                         03-022
                                         04-004
                                         06-006
                                         07-007
                                         10-005
                                         12-002

Education                                00-006
                                         00-015
                                         00-020
                                         09-004

Enclosures                               01-025

Enforcement                              00-021
                                         00-029
                                         09-001
                                         09-002
                                         10-006

Engine Design                            01-006

England                                  01-006
                                     151

-------
England (Continued)                      11-007

Environmental Protection Agency          00-012
                                         00-024
                                         00-028
                                         00-033
                                         09-002

EquiIibri urn                              02-013

Europe                                   00-034

Explosives                               00-022

Exposure Effects                         02-009
                                         12-001

Fan Noise                                01-012

Fatigue                                  02-003
                                         02-014
                                         03-017

Federal Aviation Administration          00-024

Forest Noise                             01-014
                                         01-015

Gaussian Distribution                    08-003

Generators                               01-026

Germany/East                             02-004
                                         11-008

Germany/West                             01-004
                                         07-004
                                         07-017
                                         08-002
                                         08-010
                                         10-005
                                         10-007
                                         10-008
                                         10-010

Ground Absorption                        07-003

Guidelines                               06-001
                                         12-008

Hearing Loss                             00-022
                                         02-009
                                         02-014
                                         03-020
                                         06-012
                                         11-004
                                   152

-------
Hearing Protectors                       00-020
                                         03-001

Heathrow Airport                         10-009

Helicopter Noise                         01-017

High Frequency Noise                     02-005
                                         02-007

Highway Design
IndustriaI  PI ant Desi gn
Highway Noise                            00-010
                                         07-003
                                         07-005
                                         07-013
                                         08-002

Highway Planning
Hospitals                                03-016
                                         07-017
                                         11-010
                                         11-011

Hous i ng
Hungary

Impact Noi se

ImpuIse Noi se




Industrial  Noise
                                    153

-------
 Insulation                               01-016
                                         05-001
                                         05-005
                                         11-002

 Intel Iigibi Iity                          03-001
                                         03-005
                                         06-011
                                         11-004

 Intermittent Noise                       02-015

 Israel                                   10-003

 Italy                                    03-004

Japan                                    02-015
                                         03-005
                                         03-008
                                         03-021
                                         07-011

Jet Engines                              07-008

Land Use                                 00-009
                                         07-001

Lawn Mowers                              00-019
                                         01-024
                                         02-009

Legislation, Federal                      00-005
                                         00-007
                                         00-010
                                         00-011
                                         00-013
                                         00-021
                                         00-024
                                         00-027
                                         00-029
                                         00-037
                                         08-005
                                         08-008
                                         10-004
                                         12-003

Legislation  Foreign                      00-034
                                         01-002
                                         08-002
                                         09-004
                                         10-003

Legislation, Local                        00-005
                                         00-021
                                         00-027
                                         00-038
                                         08-001
                                    154

-------
Legislation,  Local  (Continued)           08-005
                                         08-006
                                         08-011
                                         08-012
                                         09-003
                                         12-005

Legislation,  State                       00-005
                                         00-037
                                         09-012

Litigation                               08-005

Logging Noise                            01 -008
                                         01-014
                                         01-015

Los Angeles                              07-005
                                         07-013
                                         11-011

Louvers                                  01 -012

Machinery Noise                          01-003
                                         01-008
                                         01-014
                                         01-016
                                         05-005
                                         06-002
                                         07-014
                                         11-008
                                         12 006

Masking Effect                           03-001
                                         06-011

Masking Noise Systems                    05-001

Mass Transit                             10-010

Measuring Techniques                     00-016
                                         06-005

Mental Performance                       03-005

Mining                                   02-010

Monitoring System                        00-035
                                         06-007

Motor  Vehicles                           00-021
                                         00-031
                                         00-034
                                         00-037
                                         01-006
                                         01-010
                                         03-012
                                     155

-------
l"fotor Vehicles (Continued)               05-004
                                         OG-004
                                         07-012
                                         07-013
                                         08-011
                                         11-009
                                         12--003
                                         12-004

Motor Vehicle Noise
Mufflers                                 00-001
                                         01-021
                                         01-022
                                         01 -024
Neoprene

New York City                            00-038

Noise Abatement
Noise Control                            00-011
                                         00-018
                                         00-020
                                         00-028
                                         00-038
                                         01-019
                                         01-020
                                         06 -002
                                         12-006
                                         12-007

Noise Control Programs                   00-005
                                         00-030
                                         09-004
                                         10-005
                                         12-002
                                         12-007
                                    156

-------
Noise Exposure                           02-008
                                         02-009
                                         06-007
                                         08-001
                                         12-001

Noise  Intensity                          08--003

Moise  I sol ati on
Noise Measurements                       00-008
                                         01-002
                                         06-001
                                         06-003
                                         06-008
                                         06-013
                                         07-003
                                         07-018
                                         10-007
                                         11-003
                                         12-004

Noise Po!lution                          00-006
                                         00-036

Noise Reduction                          01-003
                                         01-009
                                         01-010
                                         01-011
                                         01-016
                                         01 -017
                                         01-018
                                         01-020
                                         04-004
                                         05-004
                                         07-016
                                         11 -009

'•ccupationa I Hazards                     08-004

Occupational Noise                       02-001
                                         02-005
                                         02-014
                                         04-002

Off ice Design                            05-001

Off ice Uoise                             04-004

Outboard Motors                          00-018
                                         00-019

Physiological effects                    00-026
                                         02-001
                                         02-003
                                         02-004
                                         02-007
                                         02-011
                                   157

-------
Physiological Effects  (Continued)        02-012
                                         02-013
                                         02-014
                                         02-015
                                         03-003
                                         03-013
                                         03-015
                                         03-020
                                         03-021

Pi le Drivers                             01-005
                                         01-025

Plumbing                                 03-019
                                         07-014
                                         10-009

Pneumatic Equipment                      06-005

Poland                                   02-010
                                         02-013
                                         02-014
                                         03-020
                                         06-004
                                         07-018
                                         11-010
                                         12-006

Preemption                               00-027

Product Design                           12-002

Propagation                              01-007
                                         01-015

Property Value                           04-003
                                         04-005

Psychoacoustics                          03-006

Psychological Effects                    02-001
                                         02-003
                                         02-010
                                         03-006
                                         03-013
                                         03-015
                                         03-017
                                         03-018
                                         03-020
                                         03-021

Public Complaints                        01-025
                                         01-026
                                         03-014
                                         03-019
                                         03-022
                                         06-009
                                         08-009
                                   158

-------
Pub I ic Education                         12-004

Pub Iic Reaction                          00-008
                                         03-022
                                         04-002

Railway Traffic Noise                    01-011
                                         03-023
                                         06-004
                                         07-012

Recreational Vehicles                    00-017
                                         00-018
                                         00-019
                                         01-023
                                         11-004

Refineries                               07-009

Refrigeration Plants                     07-017

Refuse Treatment Plant                   11-007

Regional  Planning                        00-013
                                         00-030

Regulations                              00-011
                                         00-029
                                         00-031
                                         00-032
                                         00-037
                                         08-004

Residential Noise                        00-012
                                         00-033
                                         04-003
                                         04-005
                                         07-003
                                         07-005
                                         07-011
                                         07-013
                                         07-016
                                         07-017

Retrofitting                             01-013
                                         07-008
                                         10-002

Road  Surface                             01-001
                                         11-002

Rock  & RolI  Music                        02-002
                                         02-006
                                         02-008
                                         02-009

Rumania                                  01-002


                                      159

-------
 Schools                                   00-006
                                          01-004
                                          03-005
                                          11-001

 Sensitivity  Thresholds                    02-005

 Sensory  Overload                          02-008

 Sleep  Interference                        02-007
                                          03-003
                                          03-007
                                          03-008
                                          03-009
                                          03-010
                                          03-011
                                          03-023

 Snowmobi Ies                               00-017
                                          00-021
                                          01-023
                                          06-003

 Sonic Boom                                01-007
                                          01-026
                                          02-011
                                          02-016
                                          02-017
                                          03-002
                                          03-003
                                          03-007
                                          03-009
                                          03-011
                                          03-013
                                          12-001

 Sonic Boom Carpet                         01-007

 Sound Absorption                          05-002

 Sound-Absorptive Materials               01-016
                                         05-001
                                         05-005

 Sound Power Level                         06-002

 Sound Pressure Level                      01-012
                                         02-002
                                         02-006
                                         06-002
                                         06-011

Soundproofing                            00-033

Soviet Union                             01-010
                                         01-011
                                         02-012
                                   160

-------
Soviet Union (Continued)                 03-014
                                         03-023
                                         08-004
                                         11-002

Space Fl ights                            03-010

Speech Interference                      03-001
                                         03-005
                                         06-011
                                         11-004

Standards                                00-012
                                         00-016
                                         00-029
                                         02-010
                                         03-016
                                         06-005
                                         06-006
                                         08-003
                                         08-004
                                         08-008
                                         10-008
                                         11-005
                                         1 1-007
                                         12-C
Startle Reactions                        02-011
                                         02-016
                                         02-017

Stress Reactions                         02-001
                                         02-007

Structures, Effect on                    01-026

Subways                                  00-023
                                         10-010

Supersonic Transport                     03-002
                                         10-001

Surveys                                  00-003
                                         00-026
                                         03-007
                                         03-008
                                         03-012
                                         03-021
                                         03-022
                                         07-018
                                         11-002
                                         11-004
                                         11-010
                                         11-011

Sweden                                   03-004
                                         05-004
                                    161

-------
Switzerland                              09-001
                                         09-004
                                         10-006

Temporary Threshold Shift                01-023
                                         02-006
                                         02-008
                                         06-012

Ti re Noise                               01--001
                                         03-012

Tractors                                 00-001
                                         01-010

Traffic Management                       07-007

Traffic Noi se                            00-005
                                         00-034
                                         01-002
                                         01-006
                                         01-027
                                         03-004
                                         03-012
                                         03-014
                                         04-004
                                         06-004
                                         06-010
                                         07-005
                                         07-006
                                         07-007
                                         10-009
                                         11-009
                                         11-011

Transportation Noise                     00-009
                                         00-010
                                         00-015
                                         00-017
                                         04-003
                                         10-003
                                         10-004
                                         10-010
                                         1 1-002

Truck Noi se                              01-001
                                         07-012
                                         07-013
                                         08-002
                                         11-003

Typewriter Noise                         11-008

Ultra Sound                              00-025

Urban Noi se                              01-002
                                         03-008
                                 162

-------
Urban Noise (Continued)                  06-010
                                         07-006
                                         07-016
                                         11-002

Urban Planning                           00-015
                                         01 -027
                                         06-004
                                         07-001
                                         07-006
                                         07-016
                                         07-018
                                         10-003
Ventilation Systems

Vibration Damping                        01-009

Vibration, Structural                    01-026

Weighting Scales                         06-008
                                         06-012

White Noise                              02-017
                                         03-010

Wi I derness Areas                         00-018

Wildlife                                 00-018
                                         02-016

Windows                                  05-003

Zoning                                   07-002
                                         08-006
                                         08-007
                                         09-003
                                         11-007

Zurich                                   09-004
                                   163

-------
Abrol, B. M,




Aizawa, R.




Al len, C. H.




Anderson, G. S.






Angevi ne, 0. L.




Anti caglia, J.






Baade, P. K.






Becker, R.






Bennin, R.




Bergsten, L.




Berzinya, A. K.




Biborosch, L.




Biehn, K.




Birchler, F.




Bobin, Ye. V.




Bonk, U.




Borsky, P. N.




Botsford, J. H.




Brammer, A. J.




Bricken, G.




Brown, L.




Brunt, J.




Rurrow;, A. A.




Burt, M. E.




Bystrzanowska, T.




Caccavari, C.
02-002
03-008
12-007
01-019
07-010

03-017

02 -009
06-012

06-002
06-006
02-004
03-013

00-038

00-001

1 1-002

01-002

11-008

09-004

01-011

02-004

03-015

06-003

12-004

00-035

10-009

01-020

03-022

07-007

02-014

08-011
08-012
Campbe II, R. A.
Caputa, T.
Carpenter, P. L.
Chotecki, B.

Cod I i n , J . B.

Cohen, A.


Cottereau, P.

Cuadra, E.
Den isov, E. i .

Dieh I . G. M.



Doak, P. E.

Dobbs, M. E.

Domanska, M.

Domanski , R.

Doster, M. E.

Dougherty, J .

Downs, M. P.

Dri scol I , J .

Emb leton , T. F.



Erski ne, J . B.

Fosca, V.

F I anagan , W.

Goldshore, L.

Goldstein, S. N.

Goncharenko, V, P.

Gorsh kov, S. I .
1 1 -004
02-014
06-012
02-013

00-003

02- 009
06-012

02-016

08-008
08-004

04-001
06-008
06-009

01-012

03-011

03-020

02-014

02-008

00-026

02-008

00-024

01-008
01-014
01-015

01-020

01-002

01-001

00-029

08-003

01-010

02-003
                                      164

-------
GottemoeI i or, F.




Gregoire, M. C.




Gri mster, W. F.




Hansen,  P.




Hasten,  J,




Heebink, T. B.




Hemenway , \i. G.
Hixon, E.




Hockey, G. R.




Howe,  J .  T.




Hurlburt, R. L.











Ivanov, N .  I.




J ackson,  C.  E .




Jackson,  E.  L.




Jones. H. H.




Jonsson,  E




Kaj land,  A.




Karagodi na,   I .  L.






Karlsson, C. G.




Kiessling, P.




Ki hI man,  T.




Knight, K, G.




Kohan, N. A.




Kolesn i kova, A. V.




Kozerenko, 0. P.
07-010

01 --01 8

01-017

08--010
00-001
05-002
02-008
01-008
01-014
01-015
00-014
03-018
00-037
04-005
06-007
08-007
10-002

11-003
01-017
00-002
02-009
03-004
03-004
02-012
03-023

02-001

02-004

05-005

002-023

02-003

02-003

03-010
Kraege, R.


Kreml , F. M.

Kryter, K. D.

Kugler, B. A.
Kuitu, H. G.
Kvitka, V.
Lane, S. R.


Lang, W. W.
Langdon , J .
Larimore, H. T.
Laudanski . A.

Lentz, J . L.

Lesser, J .

Lewi s, E .
Li ncol n , R.
Lindberg, Z. Y.
Lorenz, W.
Lukas , J . S .
Lumsden, K. G.

Man, A.

Martin, T.

Matheson, W. K.

Matsui, K.

May, D, N.

McCol I om, H .

McHahon , N. M.

07-004
10-007

00-031

02-007
03-013
01-019
07-008
10-001
07-005
07-013
11-011
12-002
06-013
00-032
02-013

00-030

08-005
08-006
00-006
00-019
11-002
03-001
03- 009
00-036

10-003

00-021

07-015

03-021

01-012

00-025

07-012

                                       165

-------
Men'shov, A.  A.




Monaghan, J.




Mori,  S.




Mug i kura, K.




Myasn ikov, V.  I.




Myles,  D. V.









Nagata, Y.




Nakamura, G.




Nath,  L. M.




Nekipelov, M.  I






Nixon,  C. W.




Ny I in,  S.




Olpin,  0.




Orski.  C. K.




Ostergaard,  P. I




Owen,  D. A.




Paccagnella,  B.




Paik,   I.  K.




Parrott, C.  D.




Pearsons, K.  S.




Pinter,  I.




Popped, N.




Poza,  F.




Priede, T.




Puzyna, C.




Rajchert, W.




Rai ney, J. T.
02-005
00-018
03-005
07-011
03-010
01-008
01-014
01-015

02-015

03-016

02-002

03-014
03-019
03-002

05-004

00-017

00-034

04-002

06-007

03-004

04-003

00-015

06-011

11-001

01-002

03-013

01-006

06-004

12-006

01-003

Rice, C. G.
Richards , E. J .
Ri ngham, R. F.
Rintelmann, W. F.
Rosenberg, C. J .
Rupert, H. M.

Ry lander, R.


Sadowski , J .

Sahai , A. N.

Sakamoto, H.

Salter, C. M.
Schenker-Spruengl i , 0.


Schmidt, H.

Schneider, M.

Schirmer, W.

Schuler, K.

Schultz, T. J.

Scott, W. N.

Seebol d, J . G.

Semczuk, B.

S i epmann, J .

Si nger, A . A.

Skorodumov, G. Ye.

Smith, W. A.

Smitley, E. K.

Soldatkina, S. A.

Spahr, H.

Spano, B.
03-007
03-003
00-010
02-006
01-005
00-009

03-003
12-001

07-018

02-002

03-021

01-005
09-001
10-006

07-002

08-001

11-008

10-010

07-012

03-012

07-014

03-020

07-017

00-033

11-003

09-002

02-006

02-012

00-008

00-012
                                      166

-------
Sp i echowi cz,  S.




Staadt, R. L.




Stacy, E.  F.




Stand I ey,  D.




Stan i os  W.




Stephens,  S.  D.




Streckenbach, J  . M.




Sulewsky,  J .  E.




Sulkowski, W.




Sutton, A.




Sutton, P.




Tanner, C.




Thackray, R.  I.




Thomas  R. J.




Toole,  F. E.




Townend,  D.  S.




Tsysar, A.  I.




V i nokur,  I.  L.




Vargovick, R. J.




Von Gierke,  H,  E.




VuIka,  G.  H.




WaIk,  F.  H.




Walker, B.




Warren, C. H.




Warren, D. G.




Watts,  J.  A.




Weber,  H.




Vtegner,  R.  L.




W i I I i ams, C. E.
02-010 Wiedefeld, J.
00-010 Wojtowicz, P.
07-003 Yakovleva, I . Ya.
00-027 Verges, L. F.
03-020 Yoerger, R.
03-006 Yoshikai , K.
01-018 Young, J . R.
05-001 Zagurskaya, L. A.
02-013 Zamarin, D. M.
00-028 Zel ler, W.
08-009 Zimmerman, M. D.
00-016
02-011
04-004
12-004
07-009
03-023
02-012
11-009
03-002
07-016
00-004
00-011
01-007
09-003
00-005
00-022
00-013
06-011
01-004
11-010
03-010
05-003
00-020
03-008
11-006
02-005
03-022
07-017
12-005


















                                         167

-------
                             GLOSSARY
The following explanations of terms are provided to assist the reader in
understanding some terms used in this publication:
A-WEIGHTED SOUND LEVEL --  The ear does not respond equally to
    frequencies, but is less efficient at low and high frequencies than it
    is at medium or  speech range frequencies.  Thus,  to obtain a single
    number representing the sound level of a noise containing a wide
    range of frequencies  in a manner representative of the ear's
    response,  it is necessary to reduce, or weight, the effects of the
    low and high frequencies with respect to the medium frequencies.
    The resultant sound level is said to be A-weighted, and the units are
    dB.  A popular  method of indicating the units, dBA, is used in this
    Digest.   The A-weighted sound level is also called the noise level.
    Sound level meters have  an A-weighting network for measuring
    A-weighted sound level.

ABSORPTION -- Absorption is a property of materials that reduces the
    amount of sound  energy reflected.  Thus,  the introduction of an
    "absorbent" into the  surfaces of a room will reduce the sound
    pressure level in that room by virtue of the fact that sound  energy
    striking  the room surfaces will not be  totally reflected.   It  should
    be mentioned that this is an entirely different process from that  of
    transmission loss through a material,  which determines  how much
    sound gets into the room via the walls,  ceiling,  and floor.  The
    effect of absorption merely reduces  the resultant  sound level in
    the room produced by energy which has already entered the room.

ABSORPTION COEFFICIENT -- A measure of  sound-absorbing ability
    of a surface.  This coefficient is defined as the  fraction of incident
    sound energy absorbed or otherwise not reflected  by the surface.
    Unless otherwise specified,  a diffuse sound field is assumed.  The
    values of sound-absorption coefficient usually range from about
    0. 01 for marble  slate to  almost 1. 0 for long absorbing wedges such as
    are used in anechoic  chambers.
                                  168

-------
HARMONIC  -- A sinusoidal  (pure-tone) component whose frequency
    is a whole-number multiple of the fundamental frequency of the
    wave.  If a component has a frequency twice that  of the funda-
    mental it is called the second harmonic.

HEARING DISABILITY  -- An actual or presumed inability,  due to
    hearing impairment,  to remain employed at full wages.

HEARING HANDICAP  --  The disadvantage imposed by a hearing
    impairment sufficient to affect one's efficiency in the situation
    of everyday living.

HEARING IMPAIRMENT  --  A deviation or change for the worse in
    either hearing structure or function, usually outside the normal
    range;  see hearing loss.

HEARING LOSS  -- At a specified frequency,  an amount, in decibels,
    by which  the threshold of audibility for  that ear exceeds a certain
    specified audiometric threshold, that is to say, the amount by
    which a person's hearing is worse than some selected norm.
    The norm may be the threshold established at  some earlier time
    for that ear,  or the average threshold for  some large population,
    or the threshold selected by some standards body for autiometric
    measurements.

HEARING LOSS FOR SPEECH  --  The difference in decibels between
    the speech levels at which the "average normal" ear and a defec-
    tive ear,  respectively,  reach the  same intelligibility,  often
    arbitrarily set at 50%.

HERTZ  -- Unit of measurement  of frequency, numerically equal
    to cycles  per second.

IMPACT  --  (1) An impact is a single collision of  one mass in motion
    -with a second mass -which may be either in motion or at rest.
    (Z)  Impact is a word  used to express the extent or severity of an
    environmental problem;  e. g. ,  the riumber of persons exposed to
    a given noise environment.
                                   169

-------
ACCELEROMETER (ACCELERATION PICKUP)  - - An electroacoustic
    transducer that responds to the acceleration of the surface to which
    the transducer is  attached, and delivers essentially equivalent elec-
    tric waves.

ACOUSTICAL POWER -- See sound power.

ACOUSTICS  --  (1) The science of sound, including the generation,
    transmission,  and effects of sound waves,  both audible and inaudible.
    (2)  The physical qualities of a room or other enclosure(such as
    size, shape, amount of sound  absorption, and amount of noise)
    which determine the audibility and perception of speech and music.

AIRBORNE SOUND  -- Sound that reaches the point of interest by
    propagation through air.

AIR FLOW RESISTANCE  --  See flow resistance.

AMBIENT NOISE LEVEL  --   The ambient noise level follows the usage
    of the word  "ambient" throughout the environmental sciences
    (except acoustics).  That is, the ambient noise level is that level
    which exists at any instant,  regardless  of source.

ANALYSIS  --  The analysis  of a  noise generally refers to the exami-
    nation composition of the noise in its various frequency bands,
    such as  octaves or third-octaves  bands.

ANECHOIC ROOM  -- An anechoic room is one whose boundaries have
    been designed  (with acoustically  absorbent materials) to absorb
    nearly all the sound incident on its boundaries,  thereby affording
    a  test room essentially free from reflected sound.

ANTINODE   (LOOP)  --  A point, line, or surface in a standing wave
    where the vibration or sound pressure has maximum amplitude.

ARTICULATION INDEX (AI)  -- A numerically calculated measure of
    the intelligibility  of transmitted or processed speech. It takes into
    account  the limitations of the  transmission path and the background
    noise.  The articulation index can range in  magnitude between 0
    and 1. 0.  If the AI is less than 0. 1, speech intelligibility is
    generally low.   If it is above 0. 6,  speech intelligibility is generally
    high.
                                  170

-------
AUDIO FREQUENCY  --  The frequency of oscillation of an audible
    sine-wave of sound; any frequency between 20 and 20, 000  Hz.
    See also frequency.

AURAL  --  Of or pertaining to the ear or hearing.

AUDIOGRAM  -- A graph showing hearing loss as a function of
    frequency.

AUDIOMETER  --  An instrument for measuring hearing sensitivity of
    hearing loss.

BACKGROUND NOISE  --  The  total of all noise in a system or situation,
    independent of the presence of the desired signal.  In acoustical
    measurements, strictly speaking, the  term "background noise"
    means electrical noise in the measurement system. However, in
    popular usage the term  "background noise" is also used with the
    same meaning as  "residual noise. "

BAFFLE  --  A baffle is a shielding structure or series of partitions used
    to increase the  effective length of the  external transmission path
    between two points in an acoustic system.  For example,  baffles
    may be used in  sound traps (as in air  conditioning ducts) or  in
    automotive mufflers to decrease the sound transmitted while
    affording  a path for air flow.

BAND --  A segment of the frequency spectrum.

BAND CENTER FREQUENCY  --   The designated  (geometric) mean
    frequency of a band of noise or other signal.   For example, 1000 Hz
    is the band center frequency for  the octave band that extends from
    707 Hz  to 1414 Hz, or for  the third-octave band  that extends from
    891 Hz  to 1123 Hz.

BAND PRESSURE  (OR POWER) LEVEL  --  The pressure (or power)
    level for  the sound contained within a  specified frequency band.
    The  band  may be specified  either by its lower and upper cut-off
    frequencies, or by its geometric  center frequency.  The width of
    the band is often indicated by a prefatory modifier; e. g. ,  octave
    band, third-octave band,  10-Hz band.
                                  171

-------
BOOM CARPET  -- The area on the ground underneath an aircraft
    flying at supersonic speeds that is hit by a sonic boom of specified
    magnitude.

BROADBAND NOISE  --  Noise with components over a wide range of
    frequencies.

C-WEIGHTED SOUND LEVEL  (dBC)  --  A quantity, in decibels,  read
    from a  standard sound-level meter that is  switched to the weighting
    network labeled "C".  The C-weighting network weights the fre-
    quencies  between  70 Hz  and 4000 Hz uniformly, but below and above
    these limits frequencies are slightly discriminated against.
    Generally, C-weighted measurements  are  essentially the same as
    overall sound-pressure  levels, which require no discrimination at
    any frequency.

COINCIDENCE EFFECT --   The coincidence effect occurs when  the
    wavelength of the  bending wave in a panel coincides with the length
    of an incident sound wave  at the angle at -which it strikes  the panel.
    At any particular  frequency,  this effect can occur only if the  wave
    in air is traveling at a particular angle with respect to the surface
    of the panel.  Under this condition a high degree of coupling is
    achieved between  the bending wave in the panel and the  sound in the
    air.  When the coincidence effect occurs, the transmission loss
    for the  panel is greatly reduced.  See also critical frequency.

COMMUNITY NOISE EQUIVALENT LEVEL  --  Community Noise
    Equivalent Level  (CNEL) is a scale which takes account of all the
    A-weighted acoustic energy received at a point, from all noise
    events causing noise levels above some prescribed value.  Weighting
    factors are included which place greater importance  upon noise
    events occurring during the evening  hours  (7:00 p.m. to 10:00 p.m.)
    and even greater importance upon noise  events at night (10:00 p.m.
    to 6:00  a. m. ).

COMPOSITE NOISE RATING --  Composite  noise  rating  (CNR) is a
    scale which takes account of the totality  of all  aircraft operations at
    an airport in quantifying the total aircraft noise environment. It
    was  the  earliest method for evaluating compatible land use around
    airports and is still in wide use by the Department of Defense in
    predicting noise environments around military airfields.
                                 172

-------
COMPOSITE NOISE RATING  --  (Cont'd)
    Basically, to calculate a CNR value one begins with a measure of
    the maximum noise magnitude from each aircraft flyby and adds
    weighting factors which sum  the cumulative effect of all flights.
    The scale used to describe individual noise events is perceived
    noise level (in PNdB);  the term  accounting for number of flights
    is 10 log-^gN  (where N is the number of flight operations),  and
    each night operation counts as much as 10 daytime operations.
    Very approximately, the  noise exposure level at a point expressed
    in the CNR scale will be  numerically  35-37 dB higher than if
    expressed in the CNEL scale.

CONTINUOUS SOUND SPECTRUM --  A continuous sound spectrum is
    comprised of components which  are continuously distributed over
    a frequency region.

CRITERION  -- A criterion, in Federal environmental usage, is a state-
    ment of the cause and  effect relationship between a given level of
    pollutant and specific effects  on  human life.

CRITICAL FREQUENCY --  The critical frequency is the lowest
    frequency at which the  coincidence  effect can occur.  At this
    frequency the coincidence angle  is 90  , that is,  the  sound wave
    is traveling parallel to the surface  of the  panel.  Below this
    frequency, the wavelength in air is greater than the bending wave-
    length in the panel.

CUTOFF FREQUENCIES --  The frequencies that mark the ends of a
    band, or at which the characteristics  of a filter change from pass
    to no-pass.

CYLINDRICAL DIVERGENCE --  Cylindrical divergence is the condi-
    tion of propagation of cylindrical waves that accounts for the
    regular decrease in intensity of  a cylindrical wave at progressively
    greater distances from the  source.  Under this condition the sound-
    pressure level decreases 3 decibels with  each doubling of distance
    from the source. See also spherical divergence.
                                  173

-------
CYLINDRICAL, WAVE --  A cylindrical wave is a wave in which the
      surfaces  of constant phase are  coaxial cylinders.  A line of closely
      spaced sound sources radiating into an open space produces a free
      sound field of cylindrical waves.  See also cylindrical divergence.

CYCLES PER SECOND  --  A measure of frequency numerically
      equivalent to Hertz.

DAMAGE RISK CRITERION  --  A statement of noise  levels  (including
      frequency,  duration, intermittancy, and other factors) above  which
      permanent hearing loss of at least a specified amount is likely to
      be sustained by a person  (to a  given degree of probability).  See
      also hearing loss,  criterion.

DAMPING --  The dissipation of energy with time  or distance.   The
      term is generally applied to the attenuation of sound in a structure
      owing to  the internal sound-dissipative properties of the structure
      or owing  to the addition of sound-dissipative materials.

DECIBEL  --  The decibel  (abbreviated  "dB") is a measure, on a logari-
      thmic scale, of the magnitude of a particular quantity  (such  as sound
      pressure, sound power,  intensity,  etc.) with respect to a standard
      reference value.  (0.0002 microbars for sound pressure and  10
      •watt for sound power).

DIFFUSE SOUND FIELD  --  The presence of many reflected waves
      (echoes)  in a room  (or auditorium) having a very small amount
      of sound  absorption, arising from repeated reflections of  sound
      in various directions.  In a diffuse field,  the  sound pressure  level,
      averaged over time, is everywhere the same and the flow of  sound
      energy is equally probable in all directions.

DIRECTIVITY  INDEX --  In a given direction from a sound  source, the
      difference in decibels between (a)  the sound-pressure level produced
      by the  source in that direction,  and (b) the  space-average sound-
      pressure level  of that  source, measured at the  same distance.

DIRECTIVITY  PATTERN  -- The directivity pattern of a source of sound
      is the hypothetical surface in space over which  the sound pressure
      levels  produced by the source are constant.  See also directivity
      index.
                                   174

-------
DOPPLER EFFECT  ( DOPPLER SHIFT) --  The apparent upward
     shift in frequency of a sound as a noise source approaches the
     listener (or vice versa), and the apparent downward shift when
     the noise source recedes.  The classic example is the change in
     pitch of a railroad whistle as the locomotive approaches and
     passes by.

DUCT LINING OR WRAPPING  --  Usually a sheet of porous material
     placed on the inner  or outer wall(s) of a duct to introduce sound
     attenuation  and heat insulation.  It is often used in air conditioning
     systems.  Linings are more effective in attenuating sound that
     travels inside along the  length of a duct, while wrappings  are more
     effective in preventing sound from being radiated  from the duct
     sidewalls into surrounding  spaces.

EFFECTIVE PERCEIVED NOISE LEVEL (EPNL)  --   A physical
     measure designed to estimate  the effective  "noisiness" of a single
     noise  event, usually an aircraft fly-over; it is derived from instan-
     taneous Perceived Noise Level (PNL) values by applying correc-
     tions for pure tones and for the duration of the noise.

ELECTROACOUSTICS   -- The science and technology of transforming
     sound waves into currents in electrical circuits   (and vice versa), by
     means of microphones,  loudspeake-rs, and electronic amplifiers
     and  filters.

FAR FIELD --   Consider any sound source in free space.  At a
     sufficient distance from the source,  the sound pressure level obeys
     the inverse-square  law  (the sound pressure decreases  6 dB with
     each doubling of  distance from the source).   Also, the sound parti-
     cle velocity is in phase with the sound pressure.   This  region is
     called the far field of the sound source.  Regions  closer to the
     source, where these two conditions do not hold, constitute the
     near field.   In an enclosure, as opposed to free space,  there can
     also sometimes be a far field region  if  there is not so much
     reflected sound that the near field and the reverberant field
     merge.  See also reverberant field.

FILTER   --  A device that transmits certain frequency components of
     the signal  (sound or electrical) incident upon it,  and rejects other
    frequency components of the incident signal.
                                 175

-------
FLOW RESISTANCE --  The flow resistance of a porous material is
    one of the  most important quantities determining the sound absorb-
    ing characteristics of the  material.  Flow resistance is a ratio of
    the pressure differential  across a sample of the porous material
    to the air velocity through it.

FOOTPRINT  (NOISE)  --  The shape and size of the geographical
    pattern of noise impact that  an aircraft makes on the areas near
    an airport while landing or taking off.

FREE SOUND FIELD (FREE FIELD)  -- A sound field in which the
    effects of obstacles or boundaries on sound propagated in  that
    field  are negligible.

FREQUENCY --  The number of times per second that the sine-wave
    of sound repeats itself,  or that the sine-wave of a vibrating object
    repeats itself.  Now expressed in Hertz(Hz),  formerly in  cycles
    per second (cps).

FUNCTION --  A quantity which varies as a result of variations of
    another quantity.

FUNDAMENTAL  FREQUENCY  --   The frequency with which a
    periodic function reproduces itself,  sometimes called the first
    harmonic,  (see also  harmonic).

GAUSSIAN DISTRIBUTION (Or  NORMAL DISTRIBUTION)  --  A term
    used  in statistics to describe the extent and frequency of deviations
    or errors.  The outstanding characteristics  are a  tendency to a
    maximum number of occurrences at or near the  center or mean
    point, the progressive decrease of frequency of occurrence with
    distance from the center,  and the symmetry of distribution on
    either side of the center.  In respect of random noise,  each
    fluctuation of amplitude  is an occurrence,  whether above or
    below the mean level; the  peak value of each fluctuation is the
    error and the distribution of errors  with time is Gaussian.

GRADIENT --  A variation of the  local speed of sound with height
    above ground or other measure  of distance causing refraction of
    sound. It is most commonly caused by rising or falling temperature
    with altitude or by differences in wind speed.
                                  176

-------
IMPACT INSULATION CLASS  (IIC)  -- A single-figure rating which
    is intended to permit the comparison  of the impact sound insula-
    ting merits of floor-ceiling assemblies in terras  of a reference
    contour.

IMPACT SOUND  --  The sound arising from the impact of a solid
    object on an  interior surface (wall, floor, or ceiling) of  a building.
    Typical sources  are footsteps,  dropped objects,  etc.

INFRASONIC  -- Of  a frequency below the audio frequency range.

INVERSE-SQUARE LAW --  The inverse-square law describes that
    acoustic situation where the mean-square pressure  changes  in
    inverse proportion to the  square of the distance  from the source.
    Under this condition the sound-pressure level decreases  6 deci-
    bels with each doubling  of distance from the  source.  See also
    spherical divergence.

ISOLATION  --  See vibration  isolator.

JET NOISE -- Noise produced by the exhaust  of a jet into its surround-
    ing atmosphere.  It is generally associated with  the turbulence
    generated along the interface between the jet stream and  the
    atmosphere.

L-JQ LEVEL  --  The sound level exceeded  10% of the time.   Corres-
    ponds  to peaks of noise  in the time history of environmental  noise
    in a particular setting.

LSO LEVEL  --  The sound level exceeded  50% of the time.
    Corresponds to the  average level of noise in a  particular setting,
    over time.

L9Q LEVEL  --  The sound level exceeded  90% of the time.
    Corresponds to the  residual noise level.

LEVEL  -- The  value of a quantity in decibels.  The level of an
    acoustical quantity  (sound pressure or sound power), in  decibels,
    is 10 times the logarithm  (base 10) of the  ratio of the quantity to
    a reference quantity of the same physical kind.
                                  177

-------
LINE SPECTRUM  --  The spectrum of a sound whose components occur
    at a number of discrete frequencies.

LIVE ROOM  --  One characterized by an unusually small amount of
    sound absorption.  See reverberation room.

LOUDNESS  -- The judgment of intensity of a sound by a human being.
    Loudness depends primarily upon the sound pressure  of the stimulus.
    Over  much  of the loudness range it takes  about a threefold increase
    in sound pressure  (approx. 10  dB) to produce a doubling of loudness.

LOUDNESS LEVEL  -- The  loudness level of a sound, in  phons,  is
    numerically equal to the median sound pressure level, in decibels,
    relative to 0. 0002 microbar,  of a free progressive wave of fre-
    quency 1000 Hz presented to listeners facing  the source, which
    in a number of trials is judged by the listeners to be equally loud.

MACH NUMBER  --  The ratio of  a  speed of a moving element  to the
    speed of sound in the surrounding medium.

MASKING  --  The action of bringing one sound (audible when heard
    alone) to inaudibility or to unintelligibility by the introduction of
    another sound.  It is most marked when the masked sound  is of
    higher frequency than the masking sound.

MASKING NOISE   --  A noise which is intense enough to render
    inaudible  or unintellibilible another sound which is simultaneously
    present.

MEAN FREE PATH  --  The average distance sound travels between
    successive reflections in a room.

MEDIUM  --  A substance carrying  a sound wave.

MICROBAR  --  A microbar is a unit of pressure,  equal  to one dyne
    per square centimeter.

MICROPHONE --  An electroacoustic transducer that responds to
     sound waves  and delivers essentially equivalent electric waves.

NEAR FIELD --  See far field.

NODE  --  A point,  line, or  surface where  a wave has zero amplitude.
                                 178

-------
NOISE  --  Any sound •which is undesirable because it interferes wit]
    speech and hearing, or is intense enough to damage hearing,  o:r
    is otherwise annoying.

NOISE CRITERION  (NC) CURVES  --  Any of several versions
    (SC, NC,  NCA,  PNC) of criteria used for rating the accepta-
    bility of continuous indoor noise levels, such as produced by
    air-handling systems.

NOISE EXPOSURE FORECAST  --  Noise exposure forecast (NEF) is a
    scale  (analogous to CNEL and  CNR) which has been used by the
    federal government in land use planning guides for  use in con-
    nection with  airports.

    In the  NEF scale, the basic measure of magnitude  for individual
    noise events is the effective perceived noise level  (EPNL), in
    units of EPNdB.  This magnitude  measure includes the effect of
    duration per event.  The terms accounting for number of flights
    and for weighting by time period are the same as in the CNR
    scale.  Very approximately,  the noise exposure level  at a point
    expressed in the NEF scale will be numerically about  33 dB
    lower  than if expressed in the CNEL scale.

NOISE INSULATION  -- See sound  insulation.

NOISE ISOLATION CLASS (NIC)  -- A single number rating derived in
    a prescribed manner from the measured values of noise reduction.
    It provides an evaluation of the sound isolation between two enclosed
    spaces that are  acoustically connected by one or more paths.

NOISE LEVEL -- See sound level.

NOISE AND NUMBER INDEX (NNI) -- A measure based  on Per-
    ceived Noise Level, and with weighting factors' added  to account
    for the number of noise  events, and used  (in some European
    countries) for rating the noise environment near airports.

NOISE POLLUTION  LEVEL  (LNp  or  NPL)  -- A  measure of the
    total community  noise,  postulated  to be applicable to both traffic
    noise and aircraft noise. It  is computed from the  "energy
    average"   of the  noise level and the standard deviation of the
    time-varying noise level.
                                  179

-------
NOISE REDUCTION (NR)  --  The noise reduction between two areas or
    rooms is  the numerical  difference,  in decibels,  of the average sound
    pressure  levels in those areas or rooms.   A measurement of "noise
    reduction"  combines the effect of the transmission loss performance
    of structures  separating the two areas  or  rooms,  plus the effect of
    acoustic absorption present in the receiving room.

NOISE REDUCTION COEFFICIENT (NRC)   --  A measure of the acous-
    tical absorption performance of a material, calculated by the aver-
    aging its  sound absorption coefficients  at 250, 500, 1000,  and 2000
    Hz, expressed to  the nearest integral multiple of 0. 05.

NORMAL, DISTRIBUTION  -- See Gaussian distribution.

NOYS  --  A unit used in the calculation of perceived noise level.

OCTAVE  --  An octave is the interval between two sounds having a
    basic frequency ratio  of two.   For example, there are 8 octaves
    on the keyboard of a standard  piano.

OCTAVE BAND  -- All of the components,  in a sound spectrum, whose
    frequencies are between two sine wave components separated by an
    octave.

OCTAVE-BAND SOUND PRESSURE LEVEL --  The integrated sound
    pressure  level of  only those sine-wave components in a specified
    octave band, for a noise or sound having a wide  spectrum.

OSCILLATION  --  The variation with time, alternately increasing and
    decreasing,  (a) of some feature of an audible sound,  such as the
    sound pressure,  or (b) of some feature of a vibrating solid object,
    such as the displacement of its surface.

PARTIAL NODE  --  A partial node is the point,  line,  or surface in a
    standing wave system where there is a minimum amplitude differ-
    ing from  zero.

PEAK SOUND PRESSURE  --  The maximum instantaneous sound
    pressure (a) for a transient or impulsive  sound  of short duration,
    or (b) in a specified time interval for a sound of long duration.
                                  180

-------
PERCEIVED NOISE LEVEL, (PNL)  --  A quantity expressed in deci-
    bels that provides a subjective assessment of the perceived
    "noisiness" of aircraft noise.   The units of Perceived Noise Level
    are Perceived Noise Decibels,  PNdB.

PERIOD  --  The duration of time  it takes for a periodic wave form
    (like  a sine wave) to repeat itself.

PERMANENT THRESHOLD SHIFT  (PTS)  --  See temporary threshold
    shift.

PHASE -- For a  particular value of the independent variable, the
    fractional part of a period through which the  independent variable
    has advanced,  measured from an arbitrary reference.

PHON  --  The unit of measurement for loudness level.
    Phon = 40 + Io    sone.
PINK NOISE  --  Noise where level decreases with increasing
    frequency to yield constant energy per octave of band width.

PITCH  --  A listener's  perception of the frequency of a pure tone; the
    higher  the frequency, the higher the pitch.

PLANE WAVE  --  A wave whose wave fronts are parallel and perpen-
    dicular to the direction in which the  wave is travelling.

PNdB  -- See perceived noise level.

PRESBYCUSIS  --  The  decline in  hearing acuity that normally occurs  as
    a person  grows older.

PURE TONE  --  A sound wave whose waveform is that of  a sine -wave.

RANDOM INCIDENCE -- If an object is in a diffuse sound field,  the
    sound waves  that comprise the sound field are said to strike the
    object from all angles of incidence at random.  See also Gaussian
    distribution.
                                 181

-------
RANDOM NOISE  --  An oscillation whose instantaneous magnitude is not
     specified for  any given instant of time.    It can be described in a
     statistical sense by probability distribution functions  giving the
     fraction of the total time that the magnitude of the noise lies within
     a specified range.

RATE OF DECAY -- Rate of decay is the time rate at which the sound-
     pressure level  (or other stated characteristic, such  as a vibra-
     tion level)  decreases at a given point and at a given time after
     the source is turned off.  The commonly used unit is  decibels per
     second.

REFRACTION --  The bending of a  sound wave from  its  original path,
     either because it is passing from  one medium to another or because
     (in air)  of a  temperature or wind gradient in the  medium.

RESIDUAL NOISE LEVEL  --  The term  "residual noise" has been
     adopted  to  mean the noise  which exists  at a point as a result of
     the combination  of many distant sources,  individually indistin-
     guishable.  In statistical terms,  it is the level which exists
     90 percent of the time.  (Acousticians should note it means the
     same level to which they have customarily applied the term
     "ambient. ")  See also background noise.

RESONANCE --  The relatively large amplitude of vibration produced
     when the frequency of some source of sound or vibration "matches"
     or synchronizes  with the natural frequency of  vibration of  some
     object, component,  or system.

RESONATOR --  A resonator is a device that resounds or vibrates in
     sympathy with some source of sound or  vibration.

RETROFIT  --  The  retroactive modification of an existing building or
     machine.  In current usage,  the most common application of the
     word  "retrofit"  is to the question of modification of existing jet
     aircraft engines  for noise abatement purposes.
                                   182

-------
REVERBERANT FIELD  --  The region in a room where the reflected
     sound dominates, as opposed to the region close to the noise
     source where the direct sound dominates.

REVERBERATION  -- The persistence of sound in  an enclosed space,
     as a result of multiple reflections,  after the sound source has
     stopped.

REVERBERATION ROOM --  A room having a long reverberation
     time,  especially designed to make the sound field inside it as
     diffuse (homogeneous)  as possible.  Also called a live room.

REVERBERATION TIME  (RT) --  The reverberation time of a  room
     is the time taken for the sound  pressure level  (or sound  intensity)
     to decrease to one-millionth  (60 dB)  of its steady state value
     when the  source of sound energy is suddenly interrupted.   It is a
     measure  of the persistence of an impulsive  sound in  a room and
     of the amount of acoustical absorption present inside the  room.

ROOM CONSTANT  -- The room constant is equal to (a) the product
     of the average absorption  coefficient of the room and the  total
     internal area of the room,  divided by (b) the quantity one minus
     the average absorption coefficient.

ROOT-MEAN-SQUARE  (RMS) --  The root-mean square value of a
     quantity that is varying as  a function of time is  obtained by
     squaring  the function at each instant,  obtaining  the average of
     the squared values over the interval of  interest, and taking the
     square root of this average.  For a sine wave,  multiply the
     RMS  value  by -\j 2 , or about 1.43, to get the peak value of the
     wave.  The RMS value,  also called the  effective value  of the
     sound pressure, is the best measure  of ordinary continuous
     sound,  but  the peak value  is necessary  for assessment of
     impulse noises.

SHIELDING  --  The attenuation of a sound by placing walls, build-
     ings, or other barriers  between a sound source and the receiver.
                                  183

-------
SINE-WAVE --  A soundwave, audible as a pure tone, in which the
     sound pressure is a sinusoidal function of time .
SONE  -- The unit of measurement for loudness.  One sone is the
    loudness of a sound whose level is 40 phons.

SONIC BOOM  --  The pressure transient produced at an observing
    point by a  vehicle that is moving past  (or over) it faster than the
    speed of sound.

SOUND  --  See acoustics  (1).

SOUND ABSORPTION COEFFICIENT  --  See absorption coefficient.

SOUND ANALYZER --  A sound analyzer is  a device for measuring the
    band pressure level or pressure-spectrum level of a sound as a
    function of frequency.

SOUND INSULATION --  (1) The use of structures  and materials
    designed to reduce the  transmission of sound from one room or
    area to another or from the exterior  to the interior of a building.
    (2)  The degree by which sound transmission is reduced by means
    of sound insulating structures  and materials.

SOUND LEVEL (NOISE LEVEL)  --  The weighted  sound pressure  level
    obtained by use of a sound level meter having a standard frequency-
    filter for attenuating part of the sound spectrum.

SOUND LEVEL METER -- An instrument,  comprising a microphone,
    an amplifier, an output meter, and frequency-weighting networks,
    that is used for the measurement of noise and sound levels in a
    specified manner.

SOUND POWER  --  Of a source of sound, the total amount of acoustical
    energy  radiated into the atmospheric air per unit time.

SOUND POWER LEVEL --  The level of  sound power, averaged  over  a
    period of time,  the reference being 10-    watts.
                                 184

-------
SOUND PRESSURE  --  (1) The minute fluctuations  in atmospheric
      pressure which accompany the passage of a sound wave; the
      pressure fluctuations on the tympanic membrane are transmitted
      to the inner ear and give rise  to the sensation of audible sound.
      (2)  For a steady  sound,  the value of the sound pressure averaged
      over a period of time.   (3) Sound pressure is usually measured
      (a) in dynes per square centimeter  (dyn/cm ),  or (b) in newtons
      per square meter  (N/m ).  1  N/m  = 10 dyn/cm   10-  times
      the  atmospheric pressure.

SOUND PRESSURE LEVEL --  The  root-mean-square value of the
      pressure fluctuations above and below atmospheric pressure
      due to a sound wave;  expressed in decibels re a reference
      pressure of 0.0002 microbars (2 x 10~5 Newtons per square
      meter).

SOUND SHADOW  -- The   acoustical equivalent of a light  shadow.   A
      sound shadow  is often partial  because  of diffraction effects.

SOUND TRANSMISSION CLASS (STC)  -- The preferred single figure
      rating system designed to give an estimate of the sound insulation
      properties of a partition or a  rank ordering of a series of partitions.
      It is intended for  use primarily when speech and office noise  con-
      stitute the principal noise problem.

SOUND TRANSMISSION COEFFICIENT  --  The fraction of incident sound
      energy transmitted through a  structural configuration.

SOUND TRANSMISSION LOSS  (TRANSMISSION LOSS)  (TL)  --  A
      measure of sound insulation provided by a structural configuration.
      Expressed in decibels,  it is 10 times the logarithm to the base 10
      of the reciprocal  of the sound  transmission coefficient of the  con-
      figuration.

SPACE-AVERAGE SOUND PRESSURE  LEVEL  -- ' The space-average
      sound-pressure level is  the sound pressure level averaged over
      all directions  at a constant distance from the source.

SPECTRUM --  Of  a soundwave, the description of its resolution  into
      components, each of different frequency and (usually) different
      amplitude and phase.
                                  185

-------
SPEECH-INTERFERENCE LEVEL   (SIL)  --  A calculated quantity
      providing a guide to the interfering effect of a noise on reception
      of speech communication.  The speech-interference level is the
      arithmetic average of the octave-band sound-pressure levels of
      the interfering noise in the most important part of the speech
      frequency range.  The levels in the three octave-frequency bands
      centered at 500, 1000,  and ZOOO Hz are commonly averaged to
      determine the speech-interference level. Numerically, the
      magnitudes of aircraft sounds in the Speech-Interference Level
      scale are approximately 18 to 22 dB  less than the  same sounds  in
      the Perceived Noise Level scale in PNdB, depending on the
      spectrum of the  sound.

SPEED (VELOCITY) OF SOUND IN AIR  -- The speed of sound in air is
      344 m/sec or 1128 ft/sec  at 78°F.

SPHERICAL DIVERGENCE   --  Spherical  divergence is the condition of
      propagation of spherical waves that relates to the regular decrease
      in intensity of a spherical sound wave at progressively greater
      distances from the source.  Under this condition the sound-
      pressure level decreases 6 decibels with each doubling of dis-
      tance from the source.  See also  cylindrical  divergence.

SPHERICAL WAVE --  A sound wave in which the surfaces of constant
      phase are concentric spheres.  A  small  (point) source radiating
      into an open space produces a free sound field of spherical waves.

SPL  --  See sound pressure level.

STANDARD  --  (1) A prescribed method of measuring acoustical
      quantitites.  Standards in this sense are promulgated by
      professional  and scientific societies like ANSI,  SAE,  ISO, etc. ,
      as well as by other groups.  (2)  In the  sense used in Federal
      environmental statutes,  a standard is a  specific statement of
      permitted environmental conditions.

STANDING WAVE  --  A periodic sound wave  having  a fixed distribution
      in space,  the result of interference of traveling sound waves of
      the same frequency and kind.   Such sound waves  are character-
      ized  by the existence of nodes, or partial nodes, and antinodes
      that are fixed in space.
                                  186

-------
STEADY-STATE SOUNDS  --  Sounds whose average characteristics
      remain constant in time.  An example of  a steady-state sound is
      an air conditioning unit.

STRUCTUREBORNE SOUND  -- Sound that reaches the point of interest,
      over at least part  of its path, by vibration of a solid structure.

SUBHARMONIC  --  A sound component of frequency a whole-number of
      times less  than the fundamental frequency of the sounds' complex
      wave.

TAPPING MACHINE  -- A device that produces a standard impulsive
      noise by letting weights drop a fixed  distance onto the floor.
      Used in tests measuring the  isolation from impact noise provided
      by various  floor-ceiling  constructions.

TEMPORARY THRESHOLD SHIFT (TTS)  --  A temporary impairment
      of hearing capability as indicated by  an increase in  the threshold
      of audibility.  By definition,  the ear  recovers after  a given period
      of time.  Sufficient exposures to noise of sufficient  intensity,
      from which the ear never completely recovers,  will lead to
      a permanent threshold shift  (PTS),  which  constitutes hearing
      loss.   See hearing loss,  threshold shift,  threshold of audibility.

THIRD-OCTAVE BAND  -- A frequency band whose cut-off frequencies
      have a ratio of 2 to the one-third power,  which is approximately
      1. 26.  The cut-off frequencies  of 891 Hz  and 1112 Hz define a
      third-octave band  in common use.  See also band center frequency.

THRESHOLD OF AUDIBILITY  (THRESHOLD OF DETECTABILITY) --
      The minimum sound-pressure level at which a person can hear
      a specified sound for a specified fraction of  trials.

THRESHOLD SHIFT  --An increase  in a hearing threshold level that
      results from exposure to noise.

TONE  --  A sound of definite pitch.   A pure tone has a sinusoidal
      wave form.

TRAFFIC NOISE INDEX (TNI) -- A measure  of the noise environment
      created by  vehicular traffic on  highways;  it is computed from
      measured values of the noise levels exceeded 10 percent and
      90 percent  of the time.
                                  187

-------
 TRANSMISSION LOSS -- See sound transmission loss.

TRANSDUCER  --  A device capable of being actuated by waves from one
      or more transmission systems or media and supplying related
      waves to one or more other transmission systems or media.
      Examples are microphones,  accelerometers, and loudspeakers.

TTS  -- See temporary threshold  shift

ULTRASONIC  --  Pertaining to sound frequencies above the audible
      sound spectrum (in general, higher than 20, 000 Hz).

VIBRATION ISOLATOR  --  A resilient support for machinery and other
      equipment that might  be a source of vibration, designed to reduce
      the amount of vibration transmitted to the building structure.

WAVEFORM  -- A presentation of some feature  of a sound wave, e. g. ,
      the sound pressure, as a graph showing the  moment-by-moment
      variation of sound pressure with time.

WAVEFRONT  --  An imaginary surface of a sound wave on its  way
      through the atmosphere.  At all points on the wavefront,  the wave
      is of equal amplitude  and phase.

WAVELENGTH --  For a periodic wave (such as sound in air), the
      perpendicular distance between analogous points on any two
      successive waves.  The wavelength of sound in  air or in water
      is inversely proportional to the frequency of the sound.  Thus
      the lower the frequency, the longer the wavelength.

WHITE NOISE  --  Noise whose energy is uniform over a wide range of
      frequencies,  being analogous in spectrum characteristics to
      white light.   White noise has a "hishing"  sound.  See also
      broadband noise.

WRAPPING  --  See duct  lining or wrapping.
                                   188

-------
                                ABBREVIATIONS




AAT                Auditory Awakening Threshold




ADIZ               Audible Noise Sensitive Warning




Al                 Acceptability Index




Al                 Articulation Index




APNL               Average Peak Noise Level




BS                 British Standards




CDR                Composite Damage Risk




CL                 Comfort Level




CNEL               Community Noise Equivalent Level




CNR                Composite Noise Rating




CPNL               Continuous Perceived Noise Level




DIN                German Industrial  Norm (Deutsche  Industrie Norm)




DME                Distance Measuring Equipment




DRC                Damage Risk Contours




ECPNL              Equivalent Continuous Perceived Noise Level




EDRL               Effective Perceived Noise Level




EEC                Electroencephalogram




EMC                Electromyogram




ENG                Electronystagmograph




EN I                 Environmental Noise Index




EPNDB              Effective Perceived Noise




FSTC               Field Sound Transmission  Class




GNL                General  Noise Level




HL                 Hearing Level




HNL                Hourly Noise Level




Hz                 Hertz




ICE                Internal  Combustion Engine





IDL                Intelligibility Disturbance Level




                                   189

-------
 ILS                Instrument Landing System

 INR                Impact Noise Rating

 IPNL               Integrated Perceived Noise Level  Loudness Level

 LL                 Loudness Level

 LOA                Level of Optimum Articulation

MAT                Minimal Aversion Threshold

MEL                Mean Energy Level

MPL                Multiple Pure Tones

MAC                Noise Abatement Climb

NC                 Noi se Criterion

NIC                Noise  Isolation Class

NIPTS              Noise-Induced Permanent Threshold Shift

NNI                 Noise Number Index

NPL                Noise Pollution Level

NR                 Noise Rating

NRC                Noise Reduction Coefficient

PNDB               Perceived Noise

PNL                Perceived Noise Level

PSD                Power Spectral  Density

PSF                Comparison Peak Overpressure

PTS                Permanent Threshold Shift

PWL                Sound Power Level

RECAT              Regulatory Effects on the Costs  of  Automative
                   Transportation

RE I L               Runway End Indicator Lights

REM                Rapid Eye Movement

RMS                Root Mean Square

ROPS               RoI I-over Protective Structures

RRL                Road Research Laboratory
                                    190

-------
RT




SAE




SENEL




SFC




S!L




SIN




SPL




SST




STC




STL




STOL




TACV




TL




TLV




TNI




TPU




TTS




UAN




VASI




VTOL




V/STOL




WECPNL
Reverberation Time




Statistical Energy Analysis




Single Event Noise Exposure Level




Space Flight Center




Speech Interference Level




Spatially  Incoherent Noise




Sound Pressure Level




Supersonic Transport




Sound Transmission Class




Sound Transmission Loss




Short Take-off and Landing




Tracked Air Cushion Vehicles




Transmission Loss




Threshold Limit Value




Traffic Noise Index




Transmission Preference Unit




Temporary Threshold Shift




Useful Auditory Area in Noise




Visual Approach Slope Indicator




Vertical  Take-off and Landing




Vertical  Short Take-off and Landing




Weighted Equipment Continuous Perceived Noise Level
                                       191

-------
AAAS

AAIN

AAOM

AAOO

ACGIH

AES

AES

AGMA

AHAM

AIAA

AICB


A I HA

AIMS

AI MA

AIP

AIPE

AMA

AMCA

ANSI

ARI

ASA

ASACOS

ASEE

ASHA

ASHRAE


AS ME
                ACRONYMS

American Association for the Advancement of Science

American Association of Industrial  Nurses

American Academy of Occupational  Medicine

American Academy of Ophthamology  and OtoIaryngoIogy

American Conference of Governmental  Industrial Hygienists

American Engineers Society

Audio-Engineering Society

American Gear Manufacturers Association

Association of Home Appliance Manufacturers

American Institute of Aeronautics and Austronautics

International Association Against Noise  (Association
Internationale Centre le Bruit)

American Industrial Hygiene Association

American Industrial Hearing Services

Acoustical  and Insulating Materials  Association

American Institute of Planners

American Institute of Plant Engineering

Automobile Manufacturers Association

Air Moving and Conditioning Association

American National Standards Institute

Air-Conditioning and Refrigeration  Institute

Acoustical  Society of America

Acoustical  Society of America Committee on Standards

American Society for Engineering  Education

American Speech and Hearing Association

American Society of Heating, Refrigerating and Air-
Conditioning Engineers

American Society of Mechanical Engineers
                                     192

-------
ASQC

ASTM

ATA

BBN

B & K

BOCA

BRS

BSI

GAG I

CCH

CEI

CERN

CHABA

C I MA

CLASS

CONGAWE


CSTB


CTA

DAL


DOT

ECAC

ECE

ECE

EEC

Ef'A

ERIC
American Society for Quality Control

American Society for Testing Material

American Trucking Association

Bolt, Beranek, and Newman

Bruel & Kjaer

Builders Official Conference of America

Building Research Station

British Standards Institution

Compressed Air and Gas Institute

Committee on Conservation of Hearing

International ElectrotechnicaI  Commission

European Organization for Nuclear Research

Committee on Hearing, Bioacoustic and Biomechanics

Construction Industry Manufacturers' Association

Citizen's League Against the Sonic Boom

International Study  Group for Conservation of Clean Air
and Water/Western Europe/

Scientific and Technical  Center for Building Construction
(Centre Scientifique et Technique du Batiment-Paris)

Chicago Transit Authority

German Noise Abatement Society  (Deutscher Arbeitsring fuer
Laermbekaernpf ung)

Department of Transportation

European Civil  Air Conference

Counci I  of Europe

Economic Commission  for Europe

European Economic Community

Engine Manufacturers' Association

Educational  Resources Information Center
                                  193

-------
ERIC/CEF


FAA

FA I


FHA

HUD

HVI
I AC

I ATA

ICAO

ICBO

I EC

IEEE

IES

IFHP

I IHT

I ITR

ILO

IMA

INCE

I RAD

ISA

ISO

JAMA

IBS


LEAA

LIA
Educational  Resources Information Center/Clearinghouse
on Educational  Facilities

Federal  Aviation Administration

International  Aeronautical  Federation (Federation
Aeronautique Internationale)

Federal  Housing Administration

Housing and Urban Development (Dept.  of)

Home Ventilating Institute
Industrial  Acoustics Company

International  Air Transport Association

International  Civil  Aviation  Organization

International  Conference of Building  Officials

International  ElectrotechnicaI  Commission

Institute of Electrical  and Electronics Engineers

Institute of Environmental  Sciences

International  Federation for  Housing  and Planning

Institute in Industrial  Hearing Testing

Illinois Institute of Technology Research

International  Labor Office

Industrial  Medical  Association

Institute of Noise Control  Engineering

Independent Research and Development  Program

Instrument Society of America

International  Standards  Organization

Journal  of American Medical  Association

Noise Abatement Office/Zurich, Switzerland/
(Laermbekaempfungsstelle)

Law Enforcement Assistance  Administration

Lead Industries Association
                                    194

-------
MAC

MASAC

NAG

NAHB

NAS/NAE


NASA

NBS

NCTCOG

NEMA

NIOSH

NIPCC

NMBTA

NSBE

NSC

OAL


OCMA

OECD

OSHA

OST

PAN

PHS

PNEUROP


RMA

SAE

SESA

SIA
Metropolitan Airports Commission

Metropolitan Airports Sound Abatement Council

Noise Abatement Committee

National Association of Home Builders

National Academy of Sciences/National Academy  of
Engineer!ng

National Aeronautics and Space Administration

National Bureau of Standards

North Central Texas Council of Governments

National Electrical Manufacturers Association

National Institute for Occupational Safety and Health

National Industrial Pollution Control Committee

National Machine Tool  Builders Association

Northwestern Students for a Better Environment

National Safety Council

Austrian Noise Abatement Society (Oesterreicnischer
Arbeitsring fuer Laermbekaempfung)

Oil Companies Materials Association

Organization for Economic Cooperation and Development

Occupational Safety Health Administration

Office of Science and Technology

Polish Academy of Sciences (Polska Akademia Nauk)

Public Health Service

European Committee of Manufacturers of Compressed Air
Equi pment

Radio Manufacturers Association

Society of Automative Engineers

Society for Experimental Stress Analysis

Swiss Association of Engineers and Architects
(Schwe i zeri scher I ngen ieur-und "rc'~. i teKter-Vere i n)
                                       195

-------
Sound and Vibration Institute

World Health Organization

Association of German Engineers (Verein Deutscher
Ingen ieure)
                   196

-------
                         LIST OF SOURCES
Aerospace Medicine                       03-022

Air Force Systems Command,
Wright-Patterson AFB, OH                 03-010

Airport Services Management              07-008
                                         07-015

American Industrial Hygiene
Association Journal                      08-001

American Journal of Public
Health and the Nation's Health           02-007

Anderson & Angevine, Inc.
E. Aurora, NY                            03-017

Annals of Occupational  Hygiene           01-020
                                         07-009
                                         08-009

AppI led Acoustics                        04-004

Archives of Environmental  Health         02-006
                                         03-004

Atlanta, Public Hearings on Noise
Abatement and Control                    00-001
                                         00-002
                                         00-003
                                         00-004

Automotive Engineering                   01-001
                                         10-004

Bethlehem Steel Co., PA                  06-003

Bolt,  Beranek & Newman, Inc.             01-005
                                         01-019

Boston, Public Hearings on Noise
Abatement and Control                    00-026
                                         00-027

Build  International                      06-013

Building Research Station  Digest         07-003

Business Week                            12-003

California Univ., L.A.                    07-005
                                         07-013
                                         11-011

Chalmers Univ. of Technology
Goteburg, Sweden                         05-005
                                  197

-------
Chicago, Public Hearings on Noise
Abatement and Control                    00-005
                                         00-006
                                         00-007
                                         00-008
                                         00-009
                                         00-010

Chicago Dept. of Environmental
Control, IL                              08-012

Chrysler Corp., Highland Pk., IL         03-012

Columbia Univ., NY                       03-015

Compressed Air Magazine                  01-009
                                         06-008
                                         06-009

Crocker, M., Proceedings of the
Purdue Noise Control  Conference,
JUL 14-16, 1971                          06-002
                                         08-011
                                         07-014

Dallas, Public Hearings on Noise
Abatement and Control                    00-011
                                         00-012
                                         00-013
                                         00-014
                                         00-015

Denver, Public Hearings on Noise
Abatement and Control                    00-017
                                         00-018
                                         00-019
                                         00-020
                                         00-021
                                         00-022

Deutscher Arbeitsring Fuer
Laermbekaempfung, Wiesbaden, Germany     07-002
                                         07-004

Ergonomics                               03-021

Feingeraetetechnik                       11-008

Ford Motor Co., Dearborn, Ml             11-009

Gigiyena i Sanitariya                    02-003
                                         02-012
                                         03-014
                                         03-023
                                         11-003
                                198

-------
Gigiyena Truda i  ProfessionaInye
Zabolevaniya                             01-010
                                         02-005
                                         08-004

Hearing & Speech News                    02-008

IBM Acoustics Lab., Poughkeepsie, NY     04-001
                                         07-010
                                         12-002

Indian Journal  of Medical  Research       02-002

Inglewood Dept. of Environmental
Standards;  CA                            04-005
                                         06-007
                                         08-007

Jansson, P. G., Conferences in
Connection with the International
Air Pollution Control  and  Noise
Abatement Exhibition, SEPT 1-6, 1971     01-006
                                         02-001

Journal of the Acoustical  Society
of America                               03-002
                                         06-006
                                         06-011
                                         06-012

Journal of Sound and Vibration           01-007
                                         01-012
                                         01-017
                                         02-011
                                         02-016
                                         03-003
                                         03-006
                                         03-007
                                         03-009
                                         03-011
                                         03-018
                                         07-007
                                         12-001

Kampf Dem Laerm                          01-004
                                         08-002
                                         10-007
                                         10-010

Koogai: Yosoku toTaisaku                 03-005
                                         03-016

Laermbekaempfung                          01-002
                                         07-017
                                         07-018
                                         09-001
                                         10-006

                                 199

-------
Machine Design                           12-005

Malecki, J., Bardadin, T.,
Pamietni k XXVI I  Ziazdu
Otolaryngologow  Polskich w
Katowicach 1968  r.                       02-013
                                         02-014
                                         03-020

Marinov, U., The Environment in
Israel, Israel National Committee on
Biosphere & Environment, Jerusalem,
1971 (60p.)                              10-003

Meditsina                                11-002

Mitre Corp., McClean, VA                 08-003

Monatschrift fuer OhrenheiIkunde
und Laryngo-Rhinologie                   03-001

Munich, Arbeitsbericht zur
Fortschreibung des StadtentwicklungspIanes
Nr. 3                                    10-005
                                         10-008

The municipal Attorney                   08-005
                                         08-006

Municipal  Review                         10-009

Myles,  D., An Acoustical Study of
Machinery on Logging Operations in
Eastern Canada                           01-014
                                         01-015

NAFTA                                    02-010

National Research Council  of
Canada, Ottawa,  ONT                      12-004

New York,  Public Hearings on Noise
Abatement and Control                    00-023
                                         00-024
                                         00-025

Nippon  Kooshu Eisei Zasshi               02-015
                                         03-008

Noise Assessment Guidelines              07-012

Noise/News                               12-007

OECD                                     06-010

Orvostudomany                            11-001
                                 200

-------
Oesterreichischer Arbeitsring fuer
Laermbekaempfung, Vienna, Austria        06-001
                                         11-005

Ostergarrd Asso., West CaIdweI I, NJ      04-002

Popular Government                       09-003

Die Presse                               12-008

Przeglad Lekarski                        11-010

Problemy Rozwoju Budownictwa             12-006

Saab-Scania/Sweden                       05-004

San Francisco, Public Hearings on
Noise Abatement and Control              00-016

Sangyoo Koogai                           07-011

Science and Engineering Newsletter
of Novosh Press Agency                   10-001

Seewirtschaft                            02-004

Sound and Vibration                      01-016
                                         02-009
                                         05-001
                                         05-002
                                         05-003
                                         06-005
                                         08-008
                                         11-004

Stanford Research Inst., Menlo
Pk., CA                                  03-013
                                         11-006

Univ. of So. Florida, Tampa              09-002

Urban Design Bulletin                    11-007

Urban Transportation Center,
Wash., DC                                04-003

Vooosnabzheniye i Sanitarnaya
Tekhnika                                 03-019

Washington, Public Hearings on
Noise Abatement and Control              00-028
                                         00-029
                                         00-030
                                         00-031
                                         00-032
                                         00-033
                                         00-034
                                   201

-------
   Washing-ton, (Continued)                   00-035
                                               00-036
                                               00-037
                                               00-038

   Zagadnienia Akustyczne w Zakladach
   Przemyslowych                              06-004

   Zurich  City Police                         09-004
                                              202
*U.S GOVERNMENT PRINTING OFFICE:i972 484-487/3561-3

-------
                                     READER RESPONSE FORM
   This form is designed to give readers an opportunity to comment and make suggestions concerning
   this pilot publication.  Please feel free to elaborate  in the space provided under No.  9.

      1.   The most useful part of Noise Facts Digest for me was (mark with an "X"):
          The least useful part was (mark with an "O"):
      3.

      4.
                 Chicago article
                 Information system article
                 Glossary
                                                       Q] EPA Hearings abstracts
                                                       Q Journals and reports abstracts
                                                       I  I Abbreviations and Acronyms
      2.   Of the  twelve abstract categories,  I was most interested in (check more than one if
          necessary):
        [3  Emission and suppression
        Q]  Physiological
        P]  Psychological/sociological
        ( i- Economic aspects
        rn  Building acoustics
        r-1  Measurement

    Environmental noise control is	

    The index was
                                                             C]  Planning and siting
                                                             Q  Legislation/standards
                                                             [j  Enforcement
                                                             Q  Program planning
                                                             Q]  Data
                                                             r~j  General
% of my job.
        Q Satisfactory
        Q Too detailed

5.   The level of the material is
                                                  Q  Difficult to use because of poor subject terms
                                                  [3  Not detailed enough

                                                  D  Too technical
                                                  n  Satisfactory
                                                  Q]  Not technical enough
      6.   How did you use Noise Facts Digest?  (check more than one if you like. )

              LJ  General information
              Q  Current awareness
              Q  As a reference to specialists
              P]  Actually applied some of the information to a particular  problem
                 I am working on.  (In what field?
              rn  Did not use
      7.   I would like to get future issues.             Q Yes

      8.   I could  supply material for future issues.    Q Yes

      9.   Specific comments and suggestions:	
                                                                 D  N°

                                                                 D  No
     10.   Name
                                               Position
          Organization
          Organizational Division

          Address
U

-------