Please read  carefully to  avoid any mistakes
             GUIDE TO  THE USE OF  MATERIALS IN THE CNRP
 GENERAL
 DATA DISTRIBUTION
 REGIONAL  OFFICES
 *  Briefing package
 *  Posters
 *  Pamphlets
 BMCS
 *  Briefing package
 *  Posters
 *  Pamphlets
 NATIONAL  TRUCK STOP OWNERS ASSOCIATION
 *  Posters
 *  Pamphlets
 INDEPENDENT TRUCK OWNERS ASSOCIATION
 *  Posters
 *  Pamphlets
 GENERAL  MAILING
 * Pamphlets
 STATE AND LOCAL GOVERNMENTS {HIGHWAY DEPARTMENT)
 *  Briefing package
 *  Posters
 *  Pamphlets
*Plans call for.EPA/DOT-BMCS regional  noise representatives to
 establish contact with State/local  agencies and brief them on
 the CNRP objectives.

-------
II   POSTERS
          The posters  announce the standards  that  have  been  promulgated
     and their effective date is  October 15,  1975.   The posters  contain
     information which will  direct the  truckers  to  more substantial
     information that  will  help them bring  their vehicles  into compliance.

     A.   Instructions

         Distributed to:  EPA Regional  offices
                          BMCS offices
                          National Truck Stop Owners Assoc.
                          Independent Truck Owners  Assoc.

         1.   Regional  offices (EPA-DOT) have  been  provided with:

             a.  400 copies
             b.  500 EPA and DOT stickers to  place  in spaces in  lower
                 part  of posters.
             c.  Offices should check to see  if  addresses  are correct.

         2.   Preparation of posters for distribution:

             a.  Place one EPA sticker  and  one DOT  sticker in the blank
                 spaces in the lower part of  the posters.   Be sure there
                 is one EPA sticker and one DOT  sticker per  poster.

             b.  Leave State/local agencies space  blank.  This will  be
                 taken care of by the corresponding State  or locality
                 they are distributed to.

         3.   Distribution:

                  Each EPA-DOT regional office and  truck associations
             will distribute posters to State and  local governments
             having noise ordinances in the area encompassed by  the
             region and who are willing to  cooperate in the  program
             and distribute the posters for proper display.   A letter
             should serve as introduction.  A model of this  letter
             follows:
                            (State/local  Agency
                                 address)
             Dear
                  It is with pleasure that I announce the inception
             of EPA-DOT's Cooperative Noise Reduction Program (CNRP).

                  EPA promulgated on October 29, 1974, its first noise
             regulation, pursuant to Section 18 of the Noise Control
             Act of 1972, known as the "Interstate Motor Carrier Regu-
             lation."  This rule established noise emission standards

-------
    for vehicles weighing in excess of 10,000 Ibs.  and
    engaged in interstate commerce.

         The purpose of the CNRP is to stimulate and
    encourage affected carriers to make early and volun-
    tary noise abatement actions prior to formal enforcement
    commencing October 15, 1975, by Department of Transpor-
    tation's Bureau of Motor Carrier Safety (DOT/BMCS).

         Anticipating DOT/BMCS enforcement activities the
    EPA and BMCS agree that it is desirable to disseminate
    to the affected public medium, information concerning
    specific requirements and means of compliance with their
    exterior noise standards.

         The success of this program will depend to a large
    extent upon the cooperation and assistance provided  by
    State and local agencies.

         We request your cooperation in the dissemination of
    posters, information pamphlets and other materials.

         I trust this request for assistance will  meet with
    your favorable response.
                                 Sincerely yours,
                                 Director
                                 Air and Hazardous  Materials
                                 Division 0£ Noise  Representative

    (Note:   This letter covers the distribution of  the  posters
            and pamphlets).

4.  Placement of Posters:

    Truck stops               Gas stations
    Fleet terminals           Public buildings
    Repair shops              Dealerships
    Weight stations           State vehicle registration
    Toll  booths               Part stores
    Highway rest areas        "Piggyback" yards
    Inspection stations       Police offices

5.  Contacts:

    BMCS, Private Truck Council,  Regular Common Carrier Conference.

-------
Ill  Pamphlets

         The pamphlets contain detailed information,  in the form of
     questions and answers, illustrating the substance of the standards.
     Sections include the regulation,  noise measurement,  voluntary com-
     pliance and contacts for further  information.

     A.  Instructions

         1.  Pamphlets have been distributed from EPA/ONAC to:

                    10,000 each to EPA Region
                    10,000 each to BMCS Region
                    15,000 each to ONAC
                     5,000 each to BMCSHQ
                    40,000 each to ONAC for distribution  to trade
                                    associations  and  magazines.

         2.  Distribution to:   State and local  agencies,  trade associ-
             ations, magazines, who will  in turn  distribute in toll
             booths, dealerships, repair shops, truck stops,  rest
             areas, inspection stations,  fleet  owners/operators,and
             public buildings.
             *Direct mail

         3.  Direct Mail
             Pamphlets  can be mailed;  postage  and  fees  paid  by  EPA.

         4.   Contacts

                  EPA region  should  get  listing  of motor  vehicles over
             10,000 Ibs.  from State  license  registry.   Coordinate with
             Bureau Motor Carrier Safety.

IV   Sound and Slide Presentations*

         Sound and slide  presentations are suitable for public  as well
     as local  and  State government consumption.  Each topic  area is
     written to permit  presentation  either singularly or  in  combination
     with one  or more other topic areas.  Program  duration is approximately
     3-5 minutes.   Presentations  are being prepared in  the following
     topics:

     A.  The Law (regulation)  - Its  Purpose  and  Impact

            Presents the motor carrier  regulation in layman terms.
         Stresses  benefits to  the public health  and welfare  and to
         the trucking community.   Contains numerical data concerning
         anticipated impact on the trucking  industry.

     B.  Health Effects of Noise

            Briefly describes the physiological and psychological
         effects of noise on humans.

-------
 C.   Physics  of  Sound

         Specifically  addresses  sound and  its difference  to noise,
     its  measurement,  and  noise  levels.

 D.   Motor Vehicle  Noise Sources and Reudction

         Identifies and addresses  principal  noise  sources.
     Suggests methods  of noise reduction for trucks.

(Note:   *Sound and  slide shows are not yet available for  distribu-
         tion.  They will  be  mailed from EPA/ONAC  as supplements.)

 E.   Voluntary Compliance

         Stresses the  advantages of early  compliance.

 F.   Need for State and  local noise ordinances

         Describes  the role of State and local  governments must
     play for effective  enforcement of  Federal  regulations.

 G.   Enforcement

         This program  addresses  the following  subtopcis:

     1.  The enforcer(s)  - who,  how, where
     2.  Measurement techniques  for these  standards,  i.e.,
         stationery, under 35 mph, and  over 35  mph.
     3.  Vilations and connections - the legal  process.

         These sound and slide  shows may be presented  at:  schools,
     PTA meetings,  Council meetings, community  workshops, etc.

         They are to be used in  a  sound/slide  projector  available
     from 3M company,  5570 Port  Royal  Road, Springfield,  Va.  22151.

 Journal Notices

     Notice of the regulations will appear in  the July,  1975
 issue of "Overdrive"Magazine and  the  July/August issue  of
 "Owner/Operator."  These periodicals  constitute the  only two
 which concentrate on the independent  trucker.

     The two  live radio scripts, included  in this section, are
 primarily for distribution to radio  stations  catering to truckers.
 A list of such radio stations is  provided.  Prompt distribution
 to stations  in your area would  be a major asset for  this program.

-------
                             INDEX
Section 1  	   Introduction
Section 2  	   Motor Carrier Noise Regulations
                                 and Standards
Section 3  	   Questions and Answers
Section 4  	   Effects of Noise on Health and
                                 Welfare
Section 5  	   Principles of Sound
Section 6  	   Major Vehicle Noise Sources and
                                 Noise Control Measures
Section 7 	   Enforcement
Section 8	State and Local  Needs
Section 9 	   Vehicle Noise Test Centers
Section 10	Low-noise Equipment Manufacturers
Section 11	   lechm'cal Data
Section 12	References to Technical Literature
Section 13	Federal, State and Local Agencies
Section 14	Trade Associations, Publications,
                                 and Radio Stations
bection 15	Guidelines for Media Releases
Section 16	EPA/DOT News Releases
Section 17	Miscellaneous

-------
1. INTRODUCTION

-------
                                   SECTION 1

                                INTRODUCTION


COOPERATIVE NOISE REDUCTION PROGRAM

Purpose
     The purpose of the Environmental Protection Agency (EPA) Cooperative Noise Reduction
Program (CNRP) is twofold  EPA would like to stimulate voluntary noise abatement actions
by owners and operators of motor vehicles engaged in interstate commerce prior to the
October 15,  1975 effective date of the Federal interstate motor carrier noise emission stan-
dards CNRP would also simultaneously educate state and local governments about the
forthcoming noise standards and assist these governments in preparation of appropriate related
noise legislation. Therefore, neither interstate carriers nor state and local governments will
be caught unaware of the noise standards; und both will understand their roles in noise reduc-
tion. At the same  time, reduced environmental noise will result prior to the effective date

Principal  Audience
     The CNRP must therefore address a wide audience - those who will comply with the
standards, those who will enforce the standards, and those who will benefit from the stan-
dards. The motor  carrier population itself ranges from major fleet companies to the one
vehicle owner/operator, all must comply equally, and, they should  be informed how to do
so.  The CNRP must, therefore,  reach individual owner/operators, small fleet (two to five
vehicles) carriers, and seasonal farm truckers. On the other hand, effective implementation
and enforcement of the Federal standard will be successful to the extent that state and local
governments adopt noise ordinances compatible with, and adequate for, cooperation in
enforcement of the Federal standard. CNRP must create an awareness in the general public
as to the way in which effective enforcement will benefit them, thereby  making noise reduc-
tion an issue which will serve as  an incentive for state and local governments to participate

Program Plan
     EPA's Office  of Noise Abatement and Control (ONAC), Technical Assistance and Opera-
tions Division has principal responsibility for CNRP.  Such activity includes development of
the program  and related materials, task assignments and overall coordinating  ONAC, in
cooperation with the Department of Transportation's Bureau of Motor Carrier Safety
(BMCS) and  the EPA and BMCS regional offices and detachments (BMCS) will disseminate
information necessary to alert the motor carrier industry, State and local governments and
other interested parties regarding the specifics of the new noise regulation.  These materials
will identify  principal vehicle noise sources, corrective measuics, enforcement responsibilities
and points of contact for assistance.

-------
     EPA regional offices have primary responsibility for briefing state and local governments
and for assisting these governments in the development of appropriate noise regulations.
The regional offices will also respond to information requests from motor carriers and the
general public
     However, BMCS regional offices, 74 detachments, and 123 inspectors have primary
responsibility for direct contact with the motor carrier community. Once CNRP gathers
momentum, EPA and BMCS staffs will collectively give public presentations on CNRP goals.
It is anticipated that state and local governmental agencies will  provide day to day informa-
tion and assistance after briefing by  EPA and/or BMCS.  Manufacturers of motor vehicle
components, i e. mufflers, fans, etc., will also play key roles in the CNRP; several have already
established  motor vehicle noise measurement centers across the nation  (over 100 m-operation
at present).  Other Federal, state and local agencies, i.e., Department of Agriculture, U.S.
Forest Service, State Farm Bureaus, etc., will also be used to distribute information.
     Information dissemination to the public will begin with the following
     1    Posting of "ALERT" placards which state maximum permissable noise levels and
         list local information centers; they will be posted at truck stops, terminals, weight
         stations, and other locations frequented by motor carriers
     2   Distribution, by direct mail and hand-out, of pamphlets containing answers to
         some twenty anticipated questions.
     3   Utilization of the news media, including newspapers, spot radio announcement
         (emphasis on approximately fifteen "trucker" oriented radio stations) and
         television.
     4   Use of trade journals and associations.
     5.   Direct contact by  Regional EPA and BMCS field personnel.
     DOT/MBCS headquarters will handle the bulk  of direct mailing to known motor carriers.
BMCS regional officer and 123 field inspectors will take the lead in the distribution of the
"ALERT" porters and pamphlets Several trade associations will also distribute material as
well as EPA regional offices

Implementation Schedule
     Completed Items
         1.   "ALERT" posters (10,000) mailed to regions (EPA and BMCS).
         2.   "Some Questions and Answers" information brochures
              a.    Mailed to regions (10,000 each  region)
              b.    Mailed to DOT/BMCS (15,000)
              c     Retained for distribution by EPA (55,000)

     June 15, 1975
         I    Regions (EPA and BMCS) to put up  "ALERT"  posters.
         2.   "Some Questions and Answers" information brochures.
                                       1-2

-------
         a.   Regions (EPA and BMCS) to distribute
         b.   DOT/BMCS to distribute
         c.   EPA headquarters to distribute
             (1)  15,000-Requests, etc.
             (2)   5,000-Public Affairs
             (3)  35,000 - Mailed directly to public

June 16,1975
     1.   EPA headquarters press release on CNRP
     2.   EPA headquarters release of two radio broadcasts (nationwide) on CNRP
     3.   EPA TV advertisement on EPA noise program.

July 1,1975
     1.   Sound on slide presentations to be sent to regions

July/August 1975
     1.   Advertisements on CNRP to appear in  motor carrier trade journals
                                 1-3

-------
  2. MOTOR CARRIER NOISE
REGULATION AND STANDARDS

-------
                                   SECTION 2

            MOTOR CARRIER NOISE REGULATION AND STANDARD
BACKGROUND
     Noise emission regulations for interstate motor carriers engaged in interstate commerce
were issued by EPA in October 1974, to become effective October 15, 1975  These regula-
tions are in accord with the Congressional requirements prescribed in Section  18 of the
Noise Control Act of 1972.  That Act further requires that no State or local government may
adopt or enforce a different standard, unless an exemption due to special local conditions is
granted by the Administrator of EPA on a case-by-case basis. However, state and local juris-
dictions employing identical standards are encouraged to act as independent enforcement
authorities The Department of Transportation, Bureau of Motor Carrier Safety, is responsible
for enforcement of the Federal regulation.

APPLICABILITY
    The new standards, which apply to all interstate motor carrier vehicles over 10,000 Ib.
gross vehicle-weight rating or gross combination weight rating (GVWR), take into account
the best available noise reduction technology and the cost of compliance (as specified in
Section 18) achievable within the I-year time period for conformance with the standard by
interstate carriers The choice of 10,000 Ibs. GVWR will be discussed later. The number
of vehicles regulated is therefore determined by two factors:  (1) those over 10,000 Ibs.
GVWR and (2) those engaged in interstate commerce.
    A motor carrier engaging in interstate commerce is defined under the definition of
Section 203 (a) of the  Interstate Commerce Act (49 U.S.C. 303 (a))  Therefore, a motor
carrier is engaged in interstate commerce if it transports commodities that arc  within the
continuous flow of interstate commerce, whether or not the motor vehicle actually crosses
state lines.

PROVISIONS
    Noise emission standards are established for both high and low speed motor vehicle
operations to quiet both engine-related noise and tire noise.  There are provisions to prevent
noisy exhaust systems and tires.
    The noise levels stipulated in the regulations are
    •   88 dBA @ 50 feet under stationary runup
    •   86 dBA @ 50 feet for speeds under 35  mph
    •   90 dBA @ 50 feet for speeds over 35 mph
                                      2-1

-------
     Furthermore, a vehicle's exhaust system must be free of noise-producing defects or
 modifications; and the vehicle cannot have new or retread tires with pocket (nonventcd
 cavity) tread design.

 SIGNIFICANCE OF THE REGULATION
     This regulation is the first significant Federal step in a series of actions to reduce high-
 way noise  This standard, applicable to in-use vehicles operated by interstate carriers, will
 have an impact within I year on reducing highway traffic noise.  The 90 dB(A) limit will
 result in a 3.6 db(A) decrease in L^n for a typical Eastern U.S. interstate highway.  This
 decrease represents a reduction of about 50 percent in the average sound energy near the
 highway
     In conjunction with the more stringent new medium and heavy-duty truck noise con-
 trol regulations proposed by the Agency, further traffic noise reduction  will be accomplished
 in a systematic time-phased manner to permit application of available technology while
 keeping the costs to meet the standards as low as reasonably possible
     As new control retrofit technology is developed and can be applied at reasonable cost,
 the interstate motor carrier regulations will be revised accordingly.  Such further revision of
 the interstate motor earner regulations will assure that new trucks manufactured m accor-
 dance with the more stringent new product noise control standards will not be degraded
 acoustically during inservice operation by interstate carriers.

 SELECTION OF 10,000 LBS. GVWR AND ABOVE
     The decision to make the standards applicable to vehicles 10,000 Ibs GVWR and
 above (medium and heavy duty trucks) resulted from an analysis of the highway noise
 problem and analyses of alternative regulator matrices. These analyses are briefly discussed
 below
     Analysis of the environmental impact of highway noise indicates that highway noise
 levels are determined almost entirely by the noise levels  of the heavier trucks.  In addition
 to their higher noise emissions, medium and heavy duty motor vehicles are distinguished
 from lighter vehicles by their typical use for long distance intercity and interstate hauling.
They are, therefore, operated many more miles per year on the average than light duty
vehicles. Since light duty vehicles are typically used for general service and delivery work
within  relatively small areas and are not usually subject to the noise emission regulations
of many different jurisdictions, national uniformity of treatment of the noise emissions
resulting from their operation does not appear necessary now.  Vehicles with a GVWR less
than 10,000 Ibs. were therefore excluded from regulation at this time
     Also studied were the effects of limiting coverage to motor vehicles over 26,000 Ibs.
GVWR or to motor vehicles with three or more axles  Such limitation would have excluded
approximately 56% of trucks over 10,000 Ibs. GVWR from  regulation. Such limitation
was not environmentally feasible, particularly because technology exists  to quiet these
trucks at reasonable cost.
     Distinction between light duty or small vehicles and medium and heavy duty vehicles,
for purposes of the regulation, is largely a technical judgment  A break at 10,000 Ibs.
GVWR is convenient because most states use that weight rating as a distinction in their
vehicle registration categories. Furthermore the Department of Commerce and the Motor
                                       2-2

-------
Vehicle Manufacturers Association divide light duty and medium duty vehicles at that weight
rating. The 10,000 Ibs. GVWR becomes even more significant because it is the standard
weight category distinction used by the Department of Transportation in their safety regu-
lations. Compatibility of the interstate motor carrier regulations with the present DOT
weight categories is advantageous, since DOT is the Federal enforcement agent.

AVAILABLE TECHNOLOGY
     Technology does exist that will enable motor carriers to meet the Federal standards
by the effective date. Such technology encompasses retrofit of exhaust  and cooling and
fan systems as well as tires. Trucks arc already being retrofitted in several states to meet
86 dB(A) limits enacted by those states.
     Most trucks that currently exceed 86 dB(A) at speeds below 35 mph require only the
addition of a muffler or the replacement of defective  muffler to comply with the standard.
Muffler manufacturers have testified publicly that enough adequate mufflers can be available
so that all trucks can comply with these interstate motor carrier regulations by the  effective
date of the regulation.  Some vehicles in violation of the proposed regulations might require
retrofit of all or part of the fan installation.  Some would  need minor work on the air intake
system  In some instances, the elimination of some crossbar tires on heavy trucks with a
large number of axles will be necessary. However, it should still be possible for these trucks
to operate with crossbar tires on the drive axles.

COST OF COMPLIANCE
     The cost to the interstate carrier industry as a whole will be somewhat less than S9
million. That cost was  calculated as follows.  Of the 5 million trucks over 10,000 Ibs. in
the United States, I million are operated by interstate carriers and are thus subject  to these
standards. Of these I million vehicles, the total cost for the 7% (or 70.000) requiring some
degree of retrofit at an  average of $135 per vehicle would amount to somewhat less than
S9 million.
     If, as a worst case, it is assumed that all 5.2 million motor vehicles above  10,000 pounds
GVWR are engaged  in interstate commerce and therefore would be required to meet the
standards and that 8% of them would require retrofit at a cost of $ 135 per vehicle, then
the total direct retrofit cost to the trucking industry could be as high as  $56 million.
     However, a retrofit cost of $ 135 per vehicle does not constitute a major burden for
the interstate motor carrier industry. For a truck running 50,000 revenue miles per year,
a $ 135 retrofit cost represents an increased expense of $.003 per revenue mile, when amor-
tized over a single year.
     These regulations will achieve  noise reduction.  As illustrated by the foregoing informa-
tion, this reduction  is achievable by reasonable application of existing technology and at
reasonable cost.
                                       2-3

-------
(ft
          TUESDAY, OCTOBER 29, 1974
          WASHINGTON, D.C.

          Volume 39 • Number 209


          PART III
           ENVIRONMENTAL
             PROTECTION
               AGENCY
            MOTOR CARRIERS
              ENGAGED IN
               INTERSTATE
               COMMERCE

             Noise Emission Standards

-------
38208
     RULES AND REGULATIONS
   Title 40—Protection of Environment
    CHAPTER I—ENVIRONMENTAL
         PROTECTION AGENCY
              [FBL 281-8]

PART 202—MOTOR CARRIERS ENGAGED
      IN INTERSTATE COMMERCE

  On July 27, 1073 notice was published
In the FEDERAL REGISTER (38 FR 20102)
that   the   Environmental   Protection
Agency (EPA or Agency) was proposing
noise emission standards for motor car-
riers engaged In Interstate  commerce.
  The purpose of this notice Is to estab-
lish final noise  emission standards  for
motor  carriers  engaged  in  Interstate
commerce by establishing  a  new Part
202 of Title 40 of the Code of Federal
Regulations.  This final rulemaklngr  is
promulgated  pursuant to section  18 of
the Noise Control Act of 1972: 86 Stat.
1234; Public Law 92-574.

             INTRODUCTION

  In section 2 of the Noise Control Act,
Congress expressed Its judgment "that.
while  primary responsibility for control
of noise rests with State and local gov-
ernments. Federal action Is essential to
deal with major  noise sources in com-
merce, control of which require national
uniformity  of treatment." As a part of
this essential Federal action, section 18
requires  the  Administrator to promul-
gate noise emission regulations for mo-
tor carriers engaged in interstate com-
merce. Such motor carriers  include com-
mon carriers by motor vehicle, contract
carriers  by  motor vehicle and  private
carriers of property by motor vehicle as
these  terms are defined by paragraphs
(a)(14), (a)(15). and  (a)(17) of sec-
tion 203 of the Interstate Commerce Act
[49 URC 303(a)J. After the effective
date of a regulation under  section  18,
applicable to  noise emissions resulting
from the operation of any motor carrier
engaged in  interstate commerce,  no
State  or political subdivision  thereof
may adopt or enforce any standard ap-
plicable  to  the  operation  of the same
equipment of such motor carrier, unless
such standard is  identical to a standard
applicable  to noise  emissions resulting
from such operation prescribed by these
regulations.  The Administrator,  after
consultation  with  the Secretary   of
Transportation  may.  however,  deter-
mine  that  the State or local standard,
control,  license,  regulation,  or  restric-
tion is necessitated by special local con-
ditions and is not in conflict with regu-
lations promulgated under  section  18.
Procedures  for State and  local govern-
ments to apply under section 18(c) (2) of
the Act will be published by this Agency
within 120 days of promulgation of this
regulation.
   The  EPA  regulations   promulgated
under section  18 are  to Include  "noise
emission standards  setting  such limits
on noise emissions resulting from oper-
ation of motor carriers engaged  in In-
terstate commerce which reflect the de-
gree   of noise   reduction   achievable
through the application  of  the best
available technology taking into account
the cost of  compliance." These final
regulations are being promulgated fol-
lowing consultation  with the Secretary
of Transportation to assure appropriate
consideration for safety and for availa-
bility of technology.  The Administrator.
after consultation with the Secretary of
Transportation,   has determined  that
the  regulations  are  to  take effect one
year after promulgation In order to per-
mit the development and application of
the  requisite  technology.  Appropriate
consideration has been given to the cost
of compliance within the one year pe-
riod.
  The regulations promulgated  under
section 18 may be revised from time to
time, in  accordance  with  subsection
18(a). They shall be in addition  to any
regulations proposed for new motor ve-
hicles under section 6.
  Section 18 of  the Noise Control Act
reflects the desire of Congress to protect
both the public health and  welfare and
interstate commerce through the  es-
tablishment of uniform national noise
emission regulations for those  opera-
tions of Interstate motor carriers which
require  national  uniformity of  treat-
ment in order  to facilitate Interstate
commerce  Such  treatment  is requisite
for those operations of interstate motor
carriers which would be burdened by con-
flicting State  and local noise controls.
Preemption under section 18 occurs only
for State or local noise regulations  on
operations  of  Interstate motor carriers
for which Federal regulations are In ef-
fect.
  After final  interstate  motor   carrier
noise emission   standards   have  been
promulgated by EPA and after consult-
ing with the Administrator  of EPA, the
Secretary of Transportation Is responsi-
ble for promulgating regulations to in-
sure compliance with the EPA standards.
This will be  accomplished through the
use of the Secretary's powers and duties
of enforcement   and inspection  as au-
thorized  by  the  Interstate Commerce
Act, the Department of Transportation
Act, and the Noise Control Act of 1972.
  In March  1974, in  accordance  with
section 5(a) (2) of the Noise Control Act
of -1972,  EPA published a document in
which levels of environmental noise req-
uisite to protect  public  health and wel-
fare were Identified.
  Recognizing that the  Noise  Control
Act  was enacted to protect the public
from adverse  health and welfare effects
due  to noise, EPA is carrying out its reg-
ulatory responsibilities for abating noise
from motor carriers through regulatory
actions under sections 6 and 18, in par-
ticular, of the Act These regulatory ac-
tions are In consonance with the levels
identified in the March 1974 document,
considei ing the mandated constraints of
available technology and cost of com-
pliance.
   Studies  have  been   performed  to
measure the  noise levels hi residential
areas  and to estimate  the number of
people subjected to noise in those areas.
The data collected clearly Indicate that
motor vehicles are the principal source of
environmental noise in urban residential
areas. Accordingly.  EPA has' developed
a regulatory  strategy that  places high
priority on the control of motor vehicle
noise.
  The  Noise Control Act contains two
sections of primary  Importance for the
control of motor vehicle noise. Section 6
contains authority by which EPA may
promulgate  noise emission performance
standards for new motor vehicles that
are applicable at the time of sale of such
vehicles. Section  18  of the Act requires
EPA to promulgate  noise emission reg-
ulations  for motor  carriers engaged  in
interstate commerce.
  Accordingly, EPA has developed and is
now implementing a motor vehicle noise
control strategy based on sections 6 and
18 of the Act that should prove to be ef-
fective In reducing environmental noise
from motor carriers In many areas to the
levels Identified as  protective of public
health and  welfare. The strategy calls
first, for the reduction, within  one year
of the promulgation  of these regulations
under section 18. of the  noise from  ve-
hicles  over   10.000   pounds GVWR  or
GCWR operated  by motor  carriers en-
gaged  In interstate  commerce, to the
lowest noise level consistent with the
noise abatement technology available for
retrofit application during the  one year
period, taking into  account the cost  of
compliance.
  Subsequently, under  section  6,  new
product noise emission standards will be
proposed  for  medium and  heavy duty
trucks It Is contemplated that the new
product  standards  will  be  maintained
for new trucks beyond the  Initial point
of sale and through subsequent modifica-
tion to  these  initial Interstate Motor
Carrier Regulations  to require that  ve-
hicles manufactured to comply with new
product performance standards and used
in interstate commerce  shall maintain
noise emission levels during  operation
which  are consistent with noise abate-
ment technology  available and required
at the time of manufacture.
  Additionally, It is anticipated that the
performance standards in the interstate
motor carrier regulations  relating  to
older vehicles will be made more stringent
as more advanced retrofit technology be-
comes available and the  cost of compli-
ance permits
   A number of component  changes re-
quired for compliance with the regula-
tions could potentially affect  the con-
sumption of fuel,  but  overall,  these
regulations  are expected to have a neg-
ligible effect on  fuel consumption. The
installation  of a  muffler  suitable for at-
taining the noise abatement levels pre-
scribed by these regulations could result
In an  Increase in the back pressure  on
the engine and in turn increase the fuel
consumption  Considering the  wide  va-
riety of mufflers available, however, a sig-
nificant increase in back  pressure Is
avoidable. For those trucks requiring in-
stallation of a quieter, more  efficient fan.
the amount of engine power wasted may
be reduced, and  the addition of a ther-
 mostatically  controlled  fan clutch  on
some trucks may decrease fuel consump-
 tion by l to  1.5 percent.
   If the installation of a suitable muffler
Increases engine back pressure. It can
cause a change In the composition of the
                              FEDERAL REGISTER, VOL  39, NO. 209—TUESDAY, OCTOBER 29,  1974

-------
                                            RULfS AND REGULATIONS
                                                                       38209
emission of gaseous air pollutants. How-
ever, since a significant increase In back
pressure is  avoidable  and  undesirable
from  a truck performance standpoint,
no  significant Increase in engine  back
pressure Is  anticipated as  a  result of
these regulations. Accordingly, these reg-
ulations are not expected to have any
significant effect on motor vehicle  air
pollutant emissions.
  The legal basis and factual conclusions
which support promulgation of this reg-
ulation were set forth in substantial de-
tail in the notice of proposed rulemaklng
published In the  FEDERAL REGISTER  on
July 27. 1973 (38 FR 20101). This publi-
cation solicited public comment, with the
comment period extending from July 27,
1973 to September 10.1973.
  On November 7. 1973.  a notice was
published In the FEDERAL REGISTER  (38
FR 23869) announcing the availability of
the "Background Document to the Pro-
posed Interstate Motor Carrier Regula-
tions" and further soliciting public  com-
ment.  This comment  period  extended
from November 7, 1973 to December 5,
1973.
  To ensure that an the Issues Involved
In the  proposed regulations had  been
fully addressed prior to the promulgation
of final regulations, a public hearing was
held on March 20 and 21, 1974 in Wash-
ington, D.C. The principal Issues reviewed
at this meeting related to the adequacy of
the available technology to meet require-
ments in the proposed standards and the
Impact  of Federal preemption  of State
and local noise regulations by these Fed-
eral Regulations. The transcript of this
hearing, plus  additional materials sub-
mitted for the record, constitute a  third
body of public comment. This comment
period extended from March 21,1974 to
Apr iM. 1974.
  Fiji lie comments received during each
of th  three public comment periods are
mat -  • Jne-: at the EPA headquarters. 401
M f  jet 3W.. Washington, D.C. 20460
and .re available to the  public during
non lal working hours (Monday to Fri-
day, 8 am to 4:30 pm).
    STTMMART OF COMMENTS RECEIVED
  The EPA has considered carefully an
of the comments received and a discus-
sion of these comments with the Agency's
response thereto follows:.
  (1) Some commenters requested clari-
fication of the types and numbers of ve-
hicles subject to the regulations.
  The Agency has addressed further In
this preamble  the types  of vehicles to
which these regulations are applicable.
The number of vehicles subject to  these
regulations  may be identified through
the definition of "Interstate commerce"
used in these regulations.
  The  definition  of "interstate  com-
merce" contained In section 203 (a) of
the  Interstate  Commerce Act   was
adopted In relevant part  by EPA. Sec-
tion 203 (a)  of that Act is cited In the
Noise Control  Act of  1B72 as defining
the  term "motor  carrier" and Is con-
sidered to be  appropriate for defining
"interstate commerce." as used In  these
regulations. Section 203(b) (8) of the In-
terstate Commerce Act expressly exempts
the operation of carriers within the com-
mercial zone of an Interstate metropoli-
tan area. EPA has not adopted such com-
mercial zone exemption since the Noise
Control Act of 1972 does not refer to sec-
tion 203 (b). Thus, a motor  carrier will
be subject to these regulations if It trans-
ports commodities which cross state lines.
  There  are  approximately  5.2 million
motor  vehicles   over  10.000   pounds
GVWR/GCWR  In  the  existing  fleets
many of which are not involved  in inter-
state commerce as defined in the regula-
tions.  The  number  of motor  vehicles
actually engaged in Interstate commprce
as defined Is not accurately known "he
Agency believes  that  most combi./
vehicles will, by definition of Intc.
motor  carrier, be found to be subject to
these regulations. Further, the Agency
has conservatively assumed  that all 5 2
million registered trucks could be subject
to this interstate motor carrier regula-
tions.
  (2) Four  commenters Indicated that
further classification  of motor vehicles
Into categories over  10.000 pounds and
promulgation of standards for each cate-
gory would be desirable. Slx'commenters
indicated  that   further  classification
would  be neither meaningful  nor de-
sirable.
  Studies performed  for EPA  Indicate
that mcU>r vehicle mean noise levels in-
crease with vehicle size (or number of
axles)  and speed. Accordingly, stand-
ards are being promulgated for both high
and low speed motor vehicle operations in
order to  quiet both engine-related noise
and tire  noise. The  Agency considered
the development of classification scheme
for trucks based on variations in weight
and number of axles. This was done in
order to  permit consideration of requir-
ing the use of "best available technology"
as it might apply to trucks of varying
configurations. Although there  Is a dif-
ference between the  mean  noise levels
of medium and heavy duty trucks. It was
found  that there Is considerable overlap
in the distributions  of noise levels of
trucks of different sizes and  that mean-
ingful  classification of vehicles at speeds
under  35 MPH within the 10,000 pound
GVWR/GCWR category Is not practical
at this time. The basic problem is that
noisy propulsion systems  are  not con-
fined to heavy duty trucks. Many truck
manufacturers offer, and  have  tradi-
tionally sold, the same diesel engines in
trucks having two or three axles,  and
due to the rise In fuel prices, more and
more medium duty trucks are  expected
to be  built with diesel engines,  which
until recently were  Installed  primarily
in heavy duty trucks. The non-existence
of a breakpoint with regard to propulsion
system selection has  also characterized
the use of noisy gasoline engines.
  An analysis of the feaslbllty of classify-
ing trucks at speeds over 35 MPH Indi-
cated  that 88  dB(A)  could  likely be
achieved by two-axle vehicles, since they
use  fewer tires than multi-axle com-
bination  vehicles. However, the analysis
of the environmental Impact of the high
speed  standard Indicated that  highway
noise levels are determined almost en-
tirely by the noise levels of the heaviest
trucks (those with four and five axles).
In the  Agency's analysis,  the require-
ment of an 88 dB(A) limit on two-axle
trucks above 10.000 pounds GVWR. and
an 82 dB(A) limit on all passenger cars
and light trucks, in addition to the cov-
erage imposed by the proposed standards,
was shown to produce essentially no fur-
ther decrease in highway noise levels be-
yond that of the proposed standards The
Agency will, however, continue its activi-
ties in endeavoring to identify particular
classifications of vehicles which will per-
mit additional  noise quieting  consider-
ing available technology and the costs of
compliance  Accordingly, no change has
been made at this time In the proposed
standards In the regulations.
  (3) Several commenters recommended
modifications in the coverage of the regu-
lations with regard to the vehicle weight
rating. Some commenters recommended
the addition of  light duty vehicles under
10,000 pounds GVWR, while other com-
menters recommended that medium duty
vehicles above 10.000  pounds GVWR be
excluded from  coverage in  the  regula-
tions.
  The Agency analyzed the effect of lim-
iting  coverage  to motor vehicles  over
26,000 pounds GVWR, or to  motor vehi-
cles having three or more axles because
several  States had requested  that cov-
erage be limited In order that more strin-
gent State regulations could be applied to
vehicles  under  26,000  pounds GVWR.
Limiting coverage to motor  vehicles over
26.000 pounds  GVWR would potentially
exclude 56  percent of all trucks over 10,-
000 pounds GVWR from Federal regula-
tions. Limiting coverage to motor  vehi-
cles with more than two axles  would ex-
clude approximately  72 percent of all
trucks over 10,000 pounds GVWR from
Federal regulation.
  Even though only about  2 percent of
all  two-axle trucks over 10,000 pounds
GVWR exceed 86 dB(A) at speeds under
35 MPH. or 90  dB(A) at speeds over 35
MPH, the  actual number of trucks ex-
ceeding the standards is not small. The
Intent of section 18 Is clearly to provide
nationwide noise regulation  for vehicles
Involved in Interstate commerce.  Fur-
ther limitation of  coverage would  allow
medium duty trucks  Involved in Inter-
state commerce to go unregulated In
many States. The Agency has determined
that at this time all  trucks over 10,000
pounds GVWR operated in  Interstate
commerce should be subject to Federal
regulations.
  Prior to  proposing  regulations appli-
cable only to vehicles over 10,000 pounds
GVWR/GCWR,  the  Agency  analyzed
both  the relative noise contribution to
traffic noise levels  and the typical use
patterns of different kinds of motor ve-
hicles. Light trucks and automobiles were
separated from medium and heavy duty
trucks for the analysis because they have
a higher power-to-weight ratio, they are
quieter  In  normal  operation  and  they
have different uses than larger vehicles.
                              FEDERAL REGISTER. VOL 39, NO. 209—TUESDAY, OCTOBER 29,  1974

-------
38210
     RULES AND REGULATIONS
  The data resulting from the analysis
clearly Indicated that medium and heavy
duty motor vehicles contribute the most
sound energy to the environment of any
highway vehicles and that any Individual
medium or heavy duty truck will typically
be perceived to be louder than other mo-
tor vehicles.
  In addition to their higher noise emis-
sions, medium and heavy duty motor ve-
hicles are distinguished from lighter ve-
hicles by their typical use for long dis-
tance Intercity  and  Interstate hauling.
They are, therefore, operated many more
miles per year on the average than light
duty  vehicles  which are normally used
for general service  and delivery work
within a relatively small area.
  Additionally, medium as well as heavy
duty  motor vehicles  operated by inter-
state motor carriers  are. In significant
numbers, constantly in transit between
different Jurisdictions, and it would  be
Impractical for  them to comply  with a
different  noise  emission standard  In
different  jurisdictions.  Thus, "medium
duty"  as well  as  "heavy duly" motor
vehicles  .operated  by  Interstate motor
carriers are construed by the Agency  to
be major noise sources In commerce, con-
trol of which  require  uniform national
treatment under section 18 of the Noise
Control Act.
  Conversely,  since  light duty  vehicles
are typically used for general service and
delivery  work  within  relatively  small
areas and are  not usually subject to the
noise  emission regulations  of many
different Jurisdictions, national uniform-
ity  of treatment of  the noise emission
resulting from their operation does not
appear necessary at this time.
  The specifications of a precise delinea-
tion  between  "light  duty" or  "small"
vehicles  and "medium and heavy duty*
vehicles  for purposes of regulation  Is
largely  an exercise  of technical Judg-
ment. EPA has chosen to make  that
delineation at  10,000 pounds GVWB/
CCWR in these regulations.
  A break at  10,000 pounds GVWR/
GCWR Is convenient because most States
use that weight rating as  a distinction
In  their vehicle registration categories.
The Department of  Commerce and the
Motor Vehicle  Manufacturers Associa-
tion divide light duty and medium duty
vehicles  at that weight rating  In addi-
tion.  It  Ii a standard weight category
distinction used by  the Department  of
Transportation  (DOT)  In  their safety
regulations, and compatibility of the In-
terstate  Motor Carrier Regulations with
the present DOT weight categories is ad-
vantageous because DOT Is the Federal
enforcement agent.  However, If in  the
future It appears that the coverage  of
the Interstate Motor Carrier Regulations
should be changed, these regulations may
be  revised pursuant  to subsection 18(a).
  Additional wording under the Appli-
cability  section of the regulations and
clarification within  the preamble has
been added In  response to these com-
ments.
   (4)  Certain   Industry  and  environ-
mental groups  questioned whether the
data collected In three States (California.
Washington, and New Jersey) were rep-
resentative  of  nationwide truck  noise
levels.
  The Agency, In order to verify previous
estimates of  potential nationwide viola-
tion rates,-has reviewed  new highway
noise survey data collected In Colorado,
Illinois,  Indiana, Kentucky,  Maryland,
New York,   Texas  and  Pennsylvania.
These States, together  with  California,
Washington, and New Jersey,  contain
over one-third of the total  number  of
trucks registered In the United States.
  The data  Indicate that  In some areas
os few as five percent of the trucks meas-
ured exceed the 90 dB(A)  level, while in
other areas the percentage  of  trucks
measured above the  90 dB(A) level may
be as high as 55  percent.  The areas re-
flecting the  higher percentages  directly
correspond to thos£  areas In which the
greatest percentage of heavy duty trucks
operate. In areas in  which a small per-
centage  of  heavy duty trucks operate,
or areas In  which State and  local noise
regulations are already being  enforced, a
smaller  percentage  of trucks are ex-
pected to violate the standard.
  On a nationwide basis  approximately
23  percent  of  the  trucks measured  In
the above cited studies exceed 90 dB(A)
at highway  speeds. The preamble to the
proposed rule-making had estimated  19
percent of the trucks measured would ex-
ceed 90 dB(A)  at highway speeds based
on a much more limited data base than is
now available.
  Further analysis was completed relat-
ing  measured  truck  highway  passoy
noise levels  to  medium and heavy  duty
motor  vehicle  State registration  data.
Results  indicate  that   approximately
seven percent of the registered in-service
motor"  vehicles  over  10,000  pounds
GVWR will  exceed 90 dB(A)  at highway
speeds when measured  at typical  road-
side sites. The  difference between meas-
ured highway passby violation rates and
predicted violation rates  for registered
vehicles Is due  to the difference In over-
the-road operating times for interstate
motor   vehicles which  is higher  than
those of other  vehicles. For example, 5-
axle combination trucks average 63,000
miles per year while single unit trucks
average less than 11,000 miles per  year.
The new data Is presented in the Back-
ground Document to  this Final  Rule-
making.
   There has been no change in the basis
on which the regulations were originally
proposed, and thus no change  In the
regulation has been  made as a result of
the new data or these comments.
   (5) Some commenters expressed con-
cern that the Agency had underestima-
ted the costs to the trucking  Industry of
compliance   with   these  regulations.
Agency estimates of costs are based  on
the actual expendltuers In 1973 of $50-
200 that were required to retrofit vehicles
to  comply  with  State  and  local noise
standards Identical  to the standards In
these regulations. The average cost esti-
mate of $114 for motor vehicles In viola-
tion of  similar standards In 1973 was
based to a  large extent on a thorough
evaluation of data describing the actual
modifications   made   on  some  7,800
medium and heavy duty trucks.
  Since prices of most commodities and
services have risen over the past year,
and appear  likely to continue to rise in
the next year,.the  average retrofit cost
can be expected to rise as well. Accord-
ingly, the Agency believes that a reason-
able average retrofit cost  estimate  for
1975 will  be $135 per applicable motor
vehicle requiring retrofit in order to meet
the standards.
  The Agency  estimates that  approxi-
mately one  million motor vehicles over
10,000 pounds  GVWR  are  engaged  In
Interstate commerce and that seven per-
cent of them  would require retrofit, at
an aveiage cost of (135 per vehicle. The
total direct  retrofit cost to the trucking
industry is therefore estimated to be $9 E
million.
  However,  If, as a worst case, It is  as-
sumed that all 5 2 million motor vehicle:
above 10,000 pounds  GVWR  would  be
required to meet the standards, then the
total direct  retrofit cost to the trucking
industry could be as high as $56 million
assuming 8 percent required retrofit
  The Agency  is of the opinion that i
retrofit cost of $135 per vehicle does  no
constitute a major burden for the inter-
state motor carrier Industry, For a trucl
running  50,000 revenue miles per year
a $135  retrofit  cost represents an  In
creased expense  of $ 003  per  revenui
mile when amortized over a single year
This increase may be compared with thi
1970 average expense of the industry o
$1 20 per revenue mile.
  From a review of the estimated num
bcr of vehicles which will require somi
degree of retrofit, the costs of such retro
fit,  and the costs to the Industry,  th
Agency  does not believe that the anticl
pated retrofit  requirement costs are si
stringent  as to preclude the promulga
tion of these noise emission standards a,
required by  the Act.
  The high speed standard exceeds  th
low speed standard only by  the nois>
differential associated with the lncreas<
in tire noise at higher speeds  Consider
able high speed noise  reduction  can b<
obtained  through  the  replacement  o
"pocket retread" tires by crossbar tire:
at no Increase fn cost or loss of perform
ance. A  four  decibel margin  has beer
added to the 86 dB(A) low speed stand-
ard In order to take tire noise Into ac-
count at high speeds  Actual experience
indicates that this will require  the elim-
ination  of some crossbar tires on some
heavy trucks that have a very large num-
ber of axles However, it should still be
possible for these trucks to operate with
crossbar tires on the drive axles.
  One industry association has  indicated
that the total direct and Indirect costs of
compliance  might  be  as high  as $150
million. No data have been submitted to
support this estimate,  but even should
this estimate be correct the Agency does
not believe it represents an unreasonable
burden.
  (6) Several Industry commenters Indi-
cated that 86 dB(A) at speeds  under 35
MPH was too  stringent and unachiev-
able within one year, while other Indus-
                              FEDERAL REGISTER. VOL 39, NO. 209—TUESDAY, OCTOBER 29.  1974

-------
              RULES AND REGULATIONS
                                                                               .18211
 stand-
try oommeaten stated
ards were feasible.
 - SPA believes that a noise level of 68
dB(A).  measured at  typical roadside
cites, similar to those used in the surveys
described in Section 4 of the Background
Document. Is achievable within one year
through  the use of best available tech-
nology by almost all medium and heavy
duty trucks in the existing fleet. Trucks
are already being retrofitted to reach 86'
dB(A) for this condition as a result of
noise regulations enacted  in  several
States. Additionally, at least one major
truck manufacturer has Indicated its in-
tention to work with suppliers to develop
a retrofit noise control package to bring
older trucks into compliance with noise
standards already proposed or which are
being anticipated for the future:  It is
also achievable by buses, since they use
the same engines and tires as trucks.
  Most  trucks currently  exceeding 86
dB(A) at speeds below 35 MPH require
only the addition of a muffler where none
was being  used  before, or the  replace-
ment of a now defective muffler In order
to be in compliance. Muffler manufac-
turers have testified in public hearings
that adequate mufflers can be available in
sufficient numbers to permit compliance
of all bracks with these Interstate Motor
Carrier Regulations within one year of
promulgation.
  (7) Three Industry commenters  Indi-
cated that more than a muffler improve-
ment would be needed for their trucks to
meet the 86 dB(A) and 90 dB(A) levels.
  There is no  disagreement with the
comment since all sources of noise from
the various componente are Intended to
be  included. The regulation is not di-
rected at noisy mufflers alone. The  eco-
nomic analysts considered the total prob-
lem of retrofit The Agency indicated In
:he  Background  Document  to the  pro-
->oseJ rulemaking that ten percent of all
vehicles u.  violation of the proposed reg-
ulations  might require retrofit of all or
part of  the fan installation and  that
five percent would need  minor work on
the air Intake system. The Agency also
indicated that approximately two  per-
cent of the in-use heavy duty dlesel fleet
that is in violation might be uneconomi-
cal to retrofit, and considered this to be
reasonable in  terms of "cost of compli-
ance." Industry commenters have Indi-
cated that the two percent number Is low.
However, no specific data has been pro-
vided by such commenters.  nor Is  addi-
tional information  available  to   EPA
which supports a higher national  per-
centage  estimate of vehicles which will
not be economical to retrofit.
   (8)  Two commenters  Indicated  that
the regulations  permit quiet vehicles to
become noisier through the use of min-
imally  effective  replacement  mufflers.
Three commenters  Indicated that this
did not appear to have occurred In States
 having similar regulations.
   Since, at the present time, a large pro-
 portion  of medium duty vehicles  have
 noise levels that are considerably  below
 80 dB
-------
38212
      RULES AND REGULATIONS
having surfaces that range from fully
paved between the source and the micro-
phone  (hard site) to largely  grass be-
tween road edge and microphone (soft
site).
  Specific  measurement  methodology
was not Included In the proposed regula-
tions as. under the  Act. the  DOT has
the responsibility after consultation with
EPA, for promulgating compliance regu-
lations; specific measurement method-
ology Is  more  appropriately addressed
by that Department through their regu-
latory responsibility. EPA has  Indicated
the rationale used to specify the  sound
levels in  the standards and anticipates
that the DOT compliance regulations
will be consistent with this rationale.
  The stationary run-up test Is a  means
of determining maximum propulsion sys-
tem  noise.  A vehicle  propulsion system
which emits a given sound power by this
test will  typically emit that same value
in use when power  requirements are
maximum for conditions of load, acceler-
ation, and grade on a hard  surface open
site.  Trucks  sometimes exhibit slightly
different noise levels when tested accord-
tag to both the stationary  run-up testa
and SAE J366a, but  the correlation be-
tween the  two  tests is  sufficient  to es-
tablish their equivalency.
  The motor carrier regulation Includes
three different  tests which  enforcement
agents may choose to use as best  meets
their circumstances. Motor  carriers may
thus encounter any or all of these tests
from time to time. These three tests are
Intended to be equally stringent, so that
those vehicles which  meet  the require-
ments of one test should have Uttle or no
difficulty with the others. An  exception
to this relation Is Intended: If a vehicle
is equipped with tires which emit more
noise than does its propulsion system, the
vehicle noise could exceed the standard
for high  speed  but be within the limits
of the other two standards.
  There  are two roadside pass-by tests,
one for speed zones of 35 MPH and less
the other for speed zones of over 35 MPH.
There is not a high correlation to  be ex-
pected in absolute noise levels  measured
In the two speed ranges because the noise
sor.-ces may be different. I.e., propulsion
system noise dominating at low  speeds
and  tire  noise at high speeds.  The high
speed standard Is 4 dB higher than the
low speed  standard  because the  maxi-
mum noise including  tires Is a function
of vehicle speed. The Intent of the regu-
lation Is to limit maximum propulsion
system noise to the  same level In both
speed -zones,  but to provide a  necessary
additional  margin to account for tire
noise.
  The comprehensive surveys conducted
by EPA show that the noise level  stand-
ards applicable to the two speed zones
are equally stringent In that equal num-
bers of vehicles are out of compliance
at the regulatory noise limits.
  The Society of Automotive Engineers'
J366a test,  which Is currently performed
by many vehicle  manufacturers, then*
customers,  and then- suppliers, is  wholly
unsuitable  for  use In roadside enforce-
ment of  a  motor carrier regulation be-
 cause of Ha technical requirements. How-
 ever, the J386a test correlates well with
 the Stationary Runup test of these reg-
 ulations. This enables a comparison to
 be made between the methodology used
 by Industry and the requirements pf the
 regulation.
   The stationary standard Is stated as
 88dB(A) while the low speed standard
 is SBdBJA)  because  of  the different
 measurement sites expected to be used.
 EPA could have stated both standards
 as equal numbers If both were to be Im-
 plemented  on pavement on a hard site
 or both on  grassy, or  soft sites. This
 number would have been the same if the
 J366 maximum noise  test  were Included
 hi the standards. In a tabular form the
 relation is:
            Stationary   Mai-nol»low  TMOa
              runup    apeed pushy
 Hud rite.....
 Bolt die	
                              BO
   (12) Four commenters indicated that
 the proposed regulations were not ade-
 quate to protect public health and wel-
 fare.
   The noise emission standards Impact
 directly upon those motor vehicles which
 presently make the most noise. The prin-
 cipal  noise reduction will be of the in-
 trusive  noise  peaks  which have  been
 widely acknowledged as more objection-
 able to people than much lower levels of
 continuous noise. These peaks can be 12
 dB or more above ambient highway noise
 levels. Therefore, significant noise reduc-
 tion benefits will he-realized by the effec-
 tive date of these regulations, producing
 substantial benefits  In  terms of public
 health and welfare as Indicated  by a de-
 crease In community noise levels near
 highways.
   In a study performed under  contract
 to the  Agency  Ldn  (day-night sound
 level) values were computed for an In-
 terstate highway, using hourly traffic
 volume statistics submitted by the Mary-
 land Department of Transportation. The
 baseline Ldn  was computed using actual
 distributions  of  noise levels for various
 classes of trucks aa measured in Mary-
' land.  The results of the study Indicated
 that a 90 db(A) limit for all trucks above
 10,000 IDS (avWR/OCWB will produce a
 3 6 dB(a) decrease In Ldn for a typical
 Eastern  US. Interstate Highway This
 represents a decrease of about 50 percent
 In the  average  sound energy near the
 highway.
   As mentioned  above, these regulations
 should not be considered alone,  but only
 as a first step In quieting motor vehicle
 noise. Under the specific requirements of
 section 18 (a)  the Agency believes that
 these regulations meet the Intent of both
 this section and  ol the Noise Control Act
 as a whole, and no change has been made
 as a result of these comments.
   (13) Two commenters stated  that the
 regulations  were Insufficient   because
 truck In-cab noise levels were  not ad-
 dressed. The Agency believes that the
 Intent of section  18 Is  to set limits on
 motor vehicle exterior  noise emissions,
not to ngulate In-cab noise levels. The
Bureau of Motor Carrier Safety of the
Department of Transportation ha* estab-
lished an  In-cab  noise  level standard.
Under the Agency's authorities  as de-
nned by section 4 of the Noise Control
Act, which states that  EPA Is  to co-
ordinate all  Federal programs relating
to noise  research and control, EPA will
coordinate with that Department in any
future revision of their In-cab noise level.
Accordingly, as 'no In-cab noise level Is
called for  here, none  has been  set.
  (14) Two commenters  Indicated that
the C scale would be more appropriate
for this regulation than the A scale.
  It has  been argued that the A-weight-
ed sound level discriminates against low
frequencies and. thus, should be replaced
by C-weighted sound level. However, the
ear also  discriminates against  low fre-
quencies so that pt low frequencies the
sound pressure level must be compara-
tively high before  It can even be heard.
Since  the   correlations  between  A-
welghted sound level and human response
are consistently better  than that  ob-
tained with the C-weighted sound level,
EPA believes that the measurement pro-
cedures using the A scale on which these
regulations  are based are appropriate,
and therefore, no change has been made.
  (15) There were a number  of com-
ments from State and local governments,
private citizens, and Industry relating to
enforcement.  Numerous  recommenda-
tions were offered for what measurement'
sites,  equipment, tolerances, etc., should
be used, and many Industry commenters
reserved  the right to comment on meas-
urement  procedures adopted for enforce-
ment purposes. EPA  will  bring  these
comments  and recommendations to the
attention of  the Department of Trans-
portation which is the Agency  respon-
sible for enforcement procedures.
  (16)  Several   commenters   recom-
mended further clarification of the spe-
cific applicability  of  the standards to
motor vehicle auxiliary equipment.
  Some  types of  auxiliary  equipment
used on vehicles operated by motor car-
riers are necessary for the comfort or
safety of passengers, or  for the pres-
ervation  of cargo. These noise control
standards are applicable to these types of
equipment and for the purpose of these
regulations  such  auxiliary  equipment
constitute essentially refrigeration or air
conditioning units, and concrete mixer
bodies and drives  These auxiliary equip-
ment noise emissions are at a level far
enough below other significant  compo-
nents of total vehicle noise, as EPA's
data indicate, to be masked by other noise
sources during normal vehicle highway
operation.
  EPA has  Identified  other auxiliary
equipment  as normally being operated
only when the transporting vehicle la-
stationary or moving at a very slow speed,
normally less than 5 MPH. Examples of
such equipment Include cranes,  asphalt
spreaders, ditch diggers, liquid or slurry
pumps,  air compressors, welders,  and
trash compactors. The  noise from the
operation of such auxiliary equipment Is
not intended to be covered by these regu-
                             FEDEtAl REGISTER. VOL  39, NO. 109—TUESDAY, OCTOBER 29,_I974

-------
                                            RUES AND REGULATIONS
                                                                       38213
       and,
are not fipplfT^t* to the noise resulting
tram the operation erf this type of equip-
ment. Die transporting vehicle, however,
if operated by an Interstate carrier and
if above  10,000 rat. GVWR/OCWR. to
subject to the Federal noise control regu-
lation when such vehicle is to  normal
highway operation.
   <17) Farther clarification of the ap-
plicability of .these standards to emer-
gency  equipment and vehicles  te  also
appropriate.  Because of  the emergency
or safety aspects of then* operation these
regulations are not applicable to vehicles
such as fire engines, ambulances, police
vana, and  rescue vans when responding to
emergency calls. Similarly, these regula-
tions are  not Intended to apply to snow
plow operation.
   Conrnnmra AGDTCT RESPOHSI TO
          PUBLIC COMHEMZS
   As mentioned In fee foregoing Agency
responses  to pabBe comments, additional
stady is required to  a  number of areas.
EPA win  evaluate (be Impact o* Uiese
regulations after they become effective
through monitoring and other activities,
Including  evaluation of DOT and State
enforcement data.
   If data  collected by or made available
to the Agency Indicate the existence  of
any problem curtailing the effectiveness
of the regulations, these regulations may
be re vised subsequent to section 18 (a) (2)
of the Act
REVISION or THX  PROPOSED RKGOTJITIOHS
        PBIOB TO PROMULGATION
  The  Interstate Motor Carrier Noise
Emission Regulations which are now be-
ing  promulgated Incorporate  several
changes from the proposed regulations
which  were  published on July 27. 1973.
These changes are based upon the public
comments received and upon  the con-
tinuing study of motor carrier noise by
the Agency. In all but one Instance such
changes are  not substantial;  they  are
only intended to  further clarify  the In-
tent Of the rpfpllnMrmn
  The sole substantive change la  the de-
letion of proposed {202.13, "Standards
for Level Street Operations 35 MPH or
Under." This section was originally pro-
posed as it was felt that vehicles which
could comply with  a  standard of 86
dB(A)  under any conditions  on high-
ways with speed limits of 35 MPH or less
could be driven so as to comply with a
standard of 80 dB(A) when operated at
constant speed on level streets with speed
limits of 35 MPH or  less. It was  the in-
tent of the Agency through this  section
to thereby regulate the manner of opera-
tion of the vehicle, oy the driver, without
impnming pjiy additional noise  reduction
requirement to the vehlde proper beyond
that needed to meet the 86 dB( A) stand-
ard.  Substantial  questions were raised
regarding  the validity of the data upon
vhlcn  the  standard  was based.  The
           a review of the relevant' data.

thgly.  tte Standards for level (Street
  Those* <**"g»« mp/fc to clarify **M> In-
tent of the regulations, and the reasons
therefore, are as follows:
  Section 202J0—DefMttous. The  def-
Inttian of "motor carrier" was expanded
to incorporate, by reference, the defini-
tion of related terms in paragraphs 14.
15, and 17, of section 203(a) of the In-
terstate Commerce Act  (49 DSC 303 A).
This treatment more closely follows sec-
tion 17(d)  of the Noise Control Act and
thereby insures  that any question as to
the definition of such related terms will
be resolved by reference to the body of
Jaw which Congress Intended to apply to
section 18.
  The definitions of "dB(A),M "sound
pressure level," and "sound level," were
changed slightly to be consistent with the
definitions of those  terms used In  the
document, "Information on Levels of En-
vironmental Noise Requisite to Protect
Public Health and Welfare with an Ade-
quate  Margin of Safety," Issued by  the
Environmental  Protection  Agency in
March 1974.  "Fast meter response" has
been expanded for clarity.
  "Gross  combination  weight rating"
(OCWR) has been added to avoid any
possible  confusion over  whether   the
regulation  Is applicable to combination
trucks  (I.e.,  tractor-trailer  rigs)  over
10,000 pounds weight rating. The  provi-
sions of Subpart B of the regulation  are
applicable to all single and combination
vehicles over 10,000 pounds weight rating.
  "Interstate commerce" has been modi-
fied to insure that any questions as to Its
scope would be resolved by reference to
section 203 (a)  of the  Interstate Com-
merce Act, consistent with the reference
to that Act in section 18 (d) of the Noise
Control Act.
  "Person" has  been deleted, since  (as
discussed below)  that word Is no longer
used in Subpart B of the regulations.
  "Street," and  "official traffic device,"
have been deleted, since proposed { 202.12
In which they were used has been deleted.
  "Muffler" has  been added to simplify
the language of  proposed S 202.14, "Vis-
ual igrhttiuA System Inspection.1*
  "Open site" has been added to further
clarify the standards.
  Section 202Jl—Effective  Date. An ef-
fective  date  of  October  l, 1974  was
originally proposed for  the regulations.
The Intent of the Agency in the notice
of proposed  mlfmaklng was that the
proposed •regulations would become  ef-
fective  one  year from the date  of
promulgation. Thin intent Is retained In
this new section.
  Section  202.12—Applicability.  •Ap-
plicability" was moved to Subpart A of
the final regulations as It  is appropri-
ately  considered  a "general provision"
of the regulations. It has been modified
to clarify the intent of the  Agency that
the standards do not apply to noise emis-
sion from wanting deilcu  or auxiliary
equipment  mounted on motor vehicles
except for  refrigeration and ah* condi-
tioning diuluiiuiHl, and  for concrete
mixer  uults and-drives. Illustrative ex-
amples have been cited for added clarity.
  Mbport B—Interstate Motor Canter
Operations. The language used in Sub-
 part B has been changed frmn, "no per-
 «on «taan operate." to "no motor carrier
 subject  to these  regulations shall  op-
 erate* • •;" and the language m{ 202.20
 was modified slightly to conform to this
 change. This change is Intended to more
 accurately reflect fee Intent of Congress
 and these regulations, that they are to
 establish uniform national noise emis-
 sion regulations for those operations of
 Interstate  motor carriers which  require
 such treatment The revised  language
 clearly Imposes  sole responsibility for
 meeting the requirements upon the motor
 carriers which own and operate the sub-
 ject motor vehicles. The proposed lan-
 guage, using the  broad term "person,"
 would have Imposed that responsibility
 upon the drivers of subject motor vehicles
 as well as the companies which operate
 them. "Motor carrier," as •defined  in
 these regulations. Includes  independent
 truckers who both own and drive their
 own vehicles.
   Section  202.2;—Standard* far  Opera-
 tion  Under Stationary  Test. The  lan-
 guage of this section has been modified
 to further clarify  that It applies  only to
 vehicles  which  have  an engine speed
 governor.  Application  of  a stationary
 run-up test to  vehicles which  are  not
 equipped  with  engine  speed limiting
 devices could result hi engine damage.
   Section  202.22—Visual Exhaust  Sys-
 tem  Inspection.  The   Intent  of   the
 Agency in  requiting motor vehicles sub-
 ject to this regulation  to be  equipped
 with exhaust system noise disslpatlve
 devices has been further clarified through
 modification of the language of proposed
 S 202.14. In addition, the exception to the
 proposed requirement relating to vehicles
 with  gas   driven  turbochargers  and
 equipped with engine brakes, which were
 demonstrated to meet the  other  stand-
 ards of  Subpart  B,  has been deleted.
 Such equipment Is Included hi the term
 "other  noise  disslpatlve device."  and
 therefore need not be treated separately.
   Section 202.23—Visual Tire Inspection.
 The Intent of the Agency was to specif-
 ically  preclude  the  use of  "pocket  re-
 tread" tires which when new are demon-
 strably noisier  without having any  ac-
 companying benefit In safety or cost over
 other types of tires. The proposed S 202.15
 has been modified in response to com-
 ments by  tire manufacturers that the
 regulation  as proposed  could have cov-
 ered some types of tires which are not
 in fact exceptionally noisy.
   Proposed Section 202.16—Enforcement
 procedures. This proposed  section has
 been deleted. As the Noise  Control Act
 places enforcement responsibilities  for
 these regulations with the Department of
 Transportation,  the section as proposed
 added nothing not specified In the Act
  Proposed Subpart  C—Special  Local
Conditions Determinations.  The  proce-
dures for applying for determinations as
called tor in section 18 (c) (2) of the Act.
will be published by EPA as "procedures"
and not as part of this regulation. Ac-
cordingly. Subpart C has been delated.
  Preemption. Under subsection U (1)
«f the Noise Control Act. after toe ef-
                                             WH. n, NO. 209—WESOAY,
                                       M, 1*74

-------
38214
RULES
                <  : ,-GUU .  ../:
fectlve date of these regulations no State
or political subdivision thereof may adopt
or enforce any  standard applicable to
noise emissions resulting from the opera-
tion of motor vehicles over 10,000 pounds
GVWR/GCWR  by  motor  carriers  en-
gaged In Interstate commerce unless such
standard  Is identical  to the standard
prescribed by these regulations. Subsec-
tion 18(c)(2). however, provides that
this section does not diminish or enhance
the rights of any State or political sub-
division thereof to establish and enforce
standards or controls  on levels of  en-
vironmental  noise,  or control,  license,
regulate, or restrict the use, operation or
movement of any product If the Admin-
istrator, after consultation with the Sec-
retary  of Transportation, determines
that  such  standard,  control,  license,
regulation, or restriction Is necessitated
by special local conditions and Is not In
conflict  with  regulations  promulgated
under section 18. Procedures for applying
for  such  determinations will  be pub-
lished  by the Agency  within 120 days.
  Conversely,  subsection 18 (c) (1) does
not  In any way preempt State or local
standards applicable to noise emissions
resulting  from any operation of Inter-
state motor carriers which Is not covered
by Federal Regulations. Thus, under the
proposed regulations States and localities
will  remain free to enact and  enforce
noise regulations on motor carrier oper-
ations other than their operation of mo-
tor vehicles over 10,000 pounds GVWR/
GCWR, without any special determina-
tion by the Administrator. Only after a
Federal regulation on noise emissions re-
sulting from a particular Interstate
motor carrier operation has become ef-
fective must the States and localities ob-
tain a special determination by the Ad-
ministrator under subsection 18(c)(2>,
In order to adopt or enforce their own
use  restrictions  or environmental noise
limits on that operation.
  Some Interstate motor carrier  opera-
tions on which no Federal noise stand-
ards or regulations have become effective,
and which may, therefore, be subjected
to State and local noise standards with-
out any special determination by the Ad-
ministrator, may Indirectly Include motor
vehicles which are covered by preemptive
Federal regulations. Motor carrier main-
tenance  shops, for example, may from
time to time emit the noise of trucks un-
dergoing tests along with noises common
to many  Industrial  operations such as
forging and grinding; and motor car-
rier terminals and parking areas Include
trucks among their many types of noise
sources.
   In most  Instances,  compliance with
State or local standards on non-Federally
regulated operations of motor carriers is
achleveable without affecting the Fed-
erally regulated  motor  vehicles  within
them. Standards on noise emissions from
repair shops, for example, can be met
by such measures as Improved sound in-
Bulatlon In the walls of the shop, buffer
zones of land between the shop and noise-
Impacted areas, and scheduling the oper-
ation of the shop to reduce noise at those
times of the day when Its Impact Is most
severe. Standards on mote*  carrier ter-
minals and parking areas L .u be met by
a variety of steps, Including reducing the
volume of loudspeaker sys- >ns by using
a distributed sound systerr. .IT replacing
speakers with two-way ra . ->s. reducing
noise emissions from equipment which la
not covered by Federal regulations. In-
stalling  noise  barriers  around noisy
equipment, acquiring additional  land to
act as a noise buffer, and locating noisy
equipment such as parked trucks with
operating refrigeration equipment as far
as possible from adjacent noise-sensitive
property. State or local regulations on
noise emissions from motor carrier oper-
ations which the motor carrier can  rea-
sonably meet by Initiating measures such
as these are not standards applicable to
noise emissions resulting from the opera-
tion of motor vehicles over 10,000 pounds
GVWR/GCWR, and thus  would not be
preempted by the  proposed  regulations.
No special determination by  the Admin-
istrator under subsection 18(c> (2) would
be necessary. State or local noise stand-
ards on operations Involved In interstate
commerce such as motor carrier termi-
nals are. of  course, subject to Constitu-
tional prohibition If they are  so stringent
as to place an undue burden on Interstate
commerce.
  In -some cases,  however,  a  State or
local noise regulation which Is not stated
as a regulation applicable to a Federally
regulated operation may be such  a regu-
lation In effect, if the only way the regu-
lation could be met would be to  modify
the equipment which meets  the Federal
regulation applicable  to It.  This would
be the case, for example, if after the  pro-
posed  regulations  become  effective,  a
State or locality attempted  to adopt or
enforce a limit on noise emissions  from
motor carrier terminals In urban areas
which could, not reasonably be  met by
measures such as noise barriers or relo-
cating the motor vehicles  to which this
regulation is applicable. Such regulation
would, In effect, require modifications to
motor vehicles even though they met the
Federal regulations and would thus  be a
regulation  applicable  to  them which
would be preempted under subsection 18
                                  streets as truck routes, and prcr 'iltlon
                                  of trucks from other streets, by i  ue or
                                  local governments, are valid with > ;i any
                                  special determination under sut. -tlon
  State or local use or operation regula-
tions which are applicable to noise emis-
sions  resulting from the operation of
Federally regulated equipment and facili-
ties can, of course, stand If the Adminis-
trator made the determinations specified
in subsection  18 (c)  (2)  regarding them.
The same would be  true of any State or
local standard on motor carrier opera-
tions which could not reasonably be met
except by modifying motor vehicles which
comply  with  the   proposed  Federal
standards.
  State and local regulations on motor
carrier operations which are not directed
at the control of noise, or which Include
noise control as only one of many pur-
poses such as  safety, traffic control, and
the like, are not preempted by subsection
18(c) (1) of the Noise Control  Act and
require no special determination under
subsection 18(c) (2)  to be adopted or en-
forced. Thus,  the designation  of  some
                                    Compliance  Procedures. Corr.'-.ance
                                  procedures are to be developed aru pro-
                                  mulgated under separate rule making by
                                  the Department of Transportation Such
                                  compliance procedures will specify mini-
                                  mum requirements for Instrumentation.
                                  test sites, and other conditions necessary
                                  to Insure uniformity  in  testing and a
                                  minimum level of precision.
                                    Enforcement of the standards is con-
                                  templated to be more efficient under some
                                  conditions If measurements are permitted
                                  to be made at Distances other than 50 feet
                                  under procedures that provide for equiv-
                                  alency  to the standards measured at 50
                                  feet.
                                    Effective Date. The effective date of
                                  these regulations Is set as one year from
                                  promulgation of  these regulations to al-
                                  low adequate time for Interstate motor
                                  carriers io make necessary equipment
                                  modifications to their motor vehicles dur-
                                  ing a normal maintenance cycle.
                                          BACKGROUND DOCUMENT
                                    Notice of the availability of the Docu-
                                  ment entitled "Background Document to
                                  proposed Interstate  Motor Carrier Reg-
                                  ulations" was published In the FEDERAL
                                  REGISTER on November 7, 1972  (38 PR
                                  23869). This document has been revised
                                  and new data have been added  This new
                                  Document Is quite lengthy, and It would
                                  be Impractical to publish it In its entirety
                                  In the FEDERAL  REGISTER.  Copies may
                                  be 6btalned from the EPA Public Infor-
                                  mation Center,  PM  215, Room 2104D,
                                  Waterside Mall. 4th and M Streets SW.,
                                  Washington. DC. 20460.  To the extent
                                  possible, the  significant aspects of the
                                  material have been presented  In sum.
                                  mary  form In the- foregoing preamble,
                                  The topics contained  In  the Document
                                  are the following:
                                    1. The EPA Motor Vehicle Noise Con-
                                  trol Strategy.
                                    2. The Technology and Cost of Quiet-
                                  ing In-Service Motor Vehicles.
                                    3.  The Relationship  Between  the
                                  Standards.
                                    4. Noise Measurement of In-Servlce
                                  Vehicles.
                                    5. The Economic  and Environmental
                                  Impact of the Regulations.
                                         FUTURE PUBUC COMMENT
                                    If as a result of continuing govern-
                                  ment studies, or as the result of develop-
                                  ments by Industry or other Institutions,
                                  It becomes  evident  to the Agency that
                                  more advanced technology is available.
                                  at some reasonable cost within a pre-
                                  scribed compliance period, prompt revi-
                                  sion of the regulations will be Initiated.
                                  Accordingly, comments and recommen-
                                  dations are solicited from all Interested
                                  persons as to new or advanced tech-
                                  nology and Its projected cost or on any
                                  other topic relevant to these regulations
                                  or revisions thereof. Prior to actual  for-
                                  mulation of any revision to these regula-
                                  tions. notice of proposed rulemaUng will
                                  be published so that there may be maxt-
                              FEDERAL REGISTER, VOL 39, NO. 209—TUESDAY,  OCTOBER 29, 1974

-------
                                            RULES  AkD REGULATIONS
                                                                      38215
tniino contribution, to the rulemaklng de-
velopment process by Interested parties.
Interested persons may submit written
data or views to the Office of Noise Abate-
ment and Control UJ3. Environmental
Protection Agency.  Washington;  D.C.
20460.
  This regulation Is promulgated under
the  authority of 42 U.B.C. 4917(a), 86
Stat. 1240.
  Dated: October 21.1974.
                    JOHN QTJARLES,
                Acting Administrator.

  Part 202 of title 40 shall read as fol-
lows:
PART'202—MOTOR CARRIERS ENGAGED
      IN INTERSTATE COMMERCE
       SubpartA—Gantrol Prevtalom
Bee.
203.10  Definitions.
303.11  Effective date.
303.13  Applicability.
Subpart D—Interstate Motor Cantor Operation*
               Standard*
303 JO  Standards for highway operations.
303-21  Standard  for operation •under sta-
        tionary test.
203.39  Visual exhaust system inspection.
203.23  Visual tin Inspection.
  AUTHORITY: flection 18, 86 Stat 1340. 43
U.8C.4917(a).
     Subpart A—General Provisions
S 202.10  Definitions.
  As used In this part, all  terms not de-
fined herein  shall have  the  meaning
given them In the Act:
  (a) "Act" means the Noise Control Act
Of 1972 (Pi. 92-574. 88 Stat. 1234)
  (b) "Common  carrier-by motor ve-
hicle" means any person who holds him-
self out to the general public to engage
in the transportation by  motor vehicle
In Interstate or foreign commerce of pas-
sengers or property or any class or clas-
ses  thereof for  compensation, whether
over regular or Irregular routes.
  (c) "Contract carrier by motor vehicle"
means any person who engages In trans-
portation by motor vehicle of passengers
or property hi, Interstate or foreign  com-
merce  for compensation  (other  than
transportation referred to In paragraph
(b)  of this section)  under  continuing
contracts  with one person or a limited
number of persons either (1)  for the
famishing of  transportation  services
through the assignment of motor vehicles
for a continuing period of tune to the
exclusive use of each person served or
(2) for the furnishing of transportation
services designed to meet the distinct
need of each Individual customer.
  (d> "Cutout or by-pass  or similar de-
vices" means devices which vary the ex-
haust system gas flow so as to discharge
the exhaust gas and acoustic energy to
tins atmosphere without passing through
the entire, length of the exhaust system.
Including  all  exhaust system sound at-
tenuation  components.
  (e> "dB(A)  means' the  standard ab-
breviation for A-welghted sound  level
la decibels.
  (f) "Exhaust system" means the sys-
tem comprised of a combination of'com-
ponents which provides for  enclosed
flow of exhaust gas from engine parts to
the atmosphere.
   (g)  "Fast meter response" means that
the fast dynamic response of the sound
level meter  shall  be  used. The fast
dynamic response shall comply  with  the
meter dynamic characteristics  In para-
graph  5.3 of  the American  National
Standard Specification for Sound Level
Meters. ANSI 81.  4-1971. This publica-
tion Is available from the American Na-
tional  Standards  Institute.  Inc.. 1420
Broadway. New York, New York 10018.
   (h> "Gross  Vehicle  Weight  Rating"
 means the value specified by
the manufacturer as the loaded weight
of a single vehicle.
   (1) "Gross Combination Weight Rat-
Ing" (GCWR) means the value  specified
.•by the manufacturer as  the loaded
weight  of a combination vehicle.
   (j) "Highway"  means  the   streets,
roads, and public ways In any State.
   (k)  "Interstate commerce" means  the
commerce between any place In a State
and any place in  another State or  be-
tween places  In the same State through
another State, whether such commerce
moves wholly by motor vehicle or partly
by motor vehicle and partly by rail,  ex-
press, water or air. This definition of "In-
terstate commerce" for purposes of these
regulations Is the same as the definition
of  "Interstate  commerce"  in  section
203 (a)  of the Interstate Commerce Act
£49 U.8.C. Section 303 (a) J.
   (1) "Motor carrier" means a  common
carrier by motor vehicle, a contract car-
rier  by motor vehicle,  or a private car-
rier of property by motor vehicle as those
terms  are defined by  paragraphs (14),
(15). and (17)  of section 203(a)  of  the
Interstate Commerce Act [49 U.S.C.  303
(a)].
   (m)  "Motor vehicle" means any vehi-
cle,  machine, tractor,  trailer, or semi-
trailer propelled or drawn by mechanical
power and used upon the highways In  the
transportation of passengers or property,
or any combination thereof, but does  not
Include any  vehicle, locomotive, or  car
operated exclusively on a rail or rails.
   (n)  "Muffler" means a device for abat-
ing the sound  of escaping gases of  an
Internal combustion engine.
   (o) "Open site" means an area that is
essentially free of large sound-reflecting
objects, such as barriers, walls,  board
fences,   signboards,  parked   vehicles.
bridges, or buildings.
   (p)  "Private carrier of property  by
motor vehicle" means any person not  in-
cluded  In  terms "common carrier  by
motor vehicle" or "contract  carrier by
motor vehicle", who or which transports
in Interstate or  foreign  commerce  by
motor vehicle property  of which such
person  Is the' owner,  lessee, or bailee,
when such transportation Is for sale,
lease; rent or bailment, or In furtherance
of any commercial enterprise.
   (q) "Sound level" means the  quantity
In dedbles measured by  a sound level
meter'satisfying the  requirements  of
^American National Standards Specifics—
tlon for Sound Level Meters Sl.4-1971.
This  publication Is available  from tbe
American National Standards Institute.
Inc.,  143D  Broadway,  New York, New
York 10018. Sound level is the frequency-
weighted sound pressure level obtained
with  the standardized dynamic char-
acteristic "fast" or "slow" and weighting
A. B, or C: unless Indicated otherwise.
the'A-weighting Is understood.
§202.11  Effective date.
  The provisions of Subpart B shall be-
come effective October 15,1975.
§ 202.12  Applicability.
   (a) The provisions of Subpart B apply
to all motor carriers engaged la Inter-
state commerce.
   (b) The provisions of Subpart B apply
only  to  those  motor  vehicles of such
motor carriers which have a gross vehicle
weight  rating   or gross  combination
weight rating In excess of 10,000  pounds,
and only when such motor vehicles are
operating under the conditions specified
In Subpart B.
   (c) Except as provided hi Subsections
(d) and (e) of this section, the provisions
of Subpart B apply to the total sound
produced by such motor vehicles when
operating under such conditions, includ-
ing  the  sound  produced  by  auxiliary
equipment  mounted on such motor ve-
hicles.
   (d) The provisions  of Subpart B do
not apply to auxiliary equipment which
Is normally  operated only  when  the
transporting vehicle is stationary or is
moving at a speed of 5 miles per hour or
less.  Examples  of'such  equipment  In-
clude, but are not limited to. cranes,
asphalt spreaders, ditch diggers, liquid
or  slurry   pumps,  air   compressors,
welders, and trash compactors.
  (e) The provisions of Subpart B do not
apply to warning devices, such as horns
and sirens: or to emergency equipment
and vehicles such as fire engines, ambu-
lances,  police vans, and  rescue vans,
when responding to emergency calls; or
to snow plows when in operation.
   Subpart B—Interstate Motor Carrier
         Operations Standards
§ 20220  Standards for highway opera-
    tions.
  No motor carrier subject to these regu-
lations shall operate any motor vehicle
of a type to which this regulation is ap-
plicable which at any time or under any
condition of highway  grade,  load,  ac-
celeration or deceleration  generates  a
sound level In excess of 88dB(A) meas-
ured  on  an open  site  with fast meter
response at 50 feet from the centerline of
lane of travel on highways with speed
limits of 35 MPH or less; or 00 dB(A)
measured on an open site with fast meter
response at  50 feet from the centerline
of lane of travel on highways with speed
limits of more than 35 MPH.
8 202.21  Standard for operation under
    stationary leal.
  No motor carrier subject to these regu-
lations ahuii operate any motor vehicle
of s type to which this regulation is ap-
plicable- which generates a sound level In
                             FDEftM teefSTHt, VOL 39, NO. 209—TUISOAY, OCTOB.   J, 1974

-------
38216

excess of 88dB(A) measured on an open
alte with last meter response at SO feet
from the  longitudinal centerllne  of the
vehicle, when Its engine  Is accelerated
from Idle  with wide  open throttle  to
governed speed with the vehicle station-
ary, transmission hi neutral, and clutch
engaged. This  section 202.21 shall not
apply  to  any  vehicle  which  is  not
equipped with an engine speed governor.

§ 202.22  Visual exhaust  system inspec-
     tion!

  No motor carrier subject  to these
regulations shall operate any motor ve-
hicle of a type to which this regulation
      RULES AND  IE* ULATr  NS

Is applicable unless the exhuost system
of such vehicle Is (1! free from defects
which  affect  sound   reduction;   (2)
equipped with a muffler or other noise
disslpatlve device; and (3)  rot equipped
with any cut-out, by-pass, ct similar de-
vice.
§ 202.23  Visual lire inspection.
  No motor carrier  subject  to  these
regulations  shall at any time operate
any  motor vehicle -of  a type  to  which
this regulation is applicable on a tire or
fares having a  tread  pattern  which as
originally manufactured, or as  newly
retreaded, is composed primarily of cavi-
ties  In  the  tread (excluding slpes and
local chunking) which are not ven"*! by
grooves to the tire shoulder or circum-
ferentially to each' other  arom..  the
tire. This section 202.23 shall  not apply
to any  motor vehicle which is demon-
strated  by the motor carrier which oper-
ates It  to be in  compliance  with  the
noise emission standard specified for op-
erations on highways with  speed  limits
of more than 35 MPH in 5 202.20  of this
subpart B, if the demonstration Is con-
ducted at the highway speed limit in ef-
fect at the inspection location,  or, if
speed is unlimited, the demonstration Is
conducted at a speed of 65 MPH.
. IFH Doc 74-25032 Filed 10-25-74,8:45 Om]
                              KDERAl REGISTER, VOL 39. NO. 209—TUESDAY, OCTOBER 29. 1974

-------
3. QUESTIONS AND ANSWERS

-------
New Federal/EPA Regulation
   Governing Interstate
      Motor Carriers
   SOME ANSWERS TO
   YOUR QUESTIONS

-------
     The questions contained in the following pages  of this  section
represent the type of information requests about the interstate motor
carrier regulation which will  probably arise.  The following answers
to these questions have been developed in concise, adequate, practical
form for your ease in handling the information requests.
     These questions and answers are also printed in the  brochures
mailed to you for distribution.  For your reference, the  brochures  are
entitled "NOISE-New Federal/EPA Regulation Governing Interstate Motor
Carriers-Some Answers to your Questions."

-------
New Federal/EPA Regulation
       governing interstate
           motor  carriers
  Some Answers To
     Your Questions
             motor carrier

               regulation

 How does the  new Federal Interstate Motor
 Carrier Reputation on noise emissions Jttect me.'

     If you own  a truck, bus or other motor
     vehicle having a GVWR/GCWR of more
     than 10,000 Ibs. and arc engaged in inter-
     state commerce, vour vehicle must not ex-
     ceed  the following  maximum  permissible
     exterior noise levels:
       •  88 dBA @  SO ft. under stationary
         runup
       •  86 dBA @ 50  ft. for speeds under 35
         mph
       •  90 dBA @ 50 ft. for speeds over 35
         mph
     Additionally,  your  vehicle's exhaust sys-
     tem must be free of noise producing defects
     or modifications and  the vehicle cannot
     have tires, as originally made or retreaded,
     with  pocket (non-vented  cavity)  tread
     design.

Who set these vehicle noise regulations?
     Congress directed the U. S. Environmental
     Protection Agency  (EPA) under the Fed-
     eral Noise Control Act of 1972 to regulate
     interstate motor carrier noise  emissions.
     EPA has established initial standards that
     permit retrofit for non-complying vehicles
     with available technology and off-the-shelf
     equipment at reasonable  cost.

Why do we need this noise regulation?
     It is  needed  to protect  both the  general
     public and vehicle operators from the harm
     of high intensity noises. Of equal impor-
     tance, the Federal regulation provides the
     interstate motor currier industry with uni-
     form national noise emission standards that
     superccdc  multiple  and  conflicting  State
     and local regulations.
 When does this Federal regulation g!» into effect?
     October  15, 1975. However, State and lo-
     cal regulations remain in effect until this
     date  regardless  of how they  compare  to
     the Federal standard.

 Why are there three  different noise level stand*
 ards?
     For  flexibility of enforcement. The sta-
     tionary runup test is a quick, reliable test
     that vehicle inspectors and owners can use
     to test for maximum noise emissions. The
     low speed test is provided for jurisdictions •
     primarily concerned with urban noise. The
     high  speed test  accounts  for  tire noise;
     that's why its limits arc higher. All three
     tests  are  intended to be equally stringent.
                noise

         measurement

What is a 'dBA' and how is it related to noise?
    dB   is the abbreviation for the term deci-
    bel, a measure of noise level. Measurements
    in terms of human hearing response arc
    described technically as A-wcightcd  and
    are expressed in  dBA. The  louder the
    sound,  the  higher  the  decibel  reading.
    Sound is measured with a sound level meter
    that  reads  in dBA.  Some typical sound
    levels are:  threshold of hearing (0 dBA);
    rustling leaves (20 dBA); soft-whisper (30
    dBA);  conversational  speech (60 dBA);
    heavy city  traffic  (85 dBA); discotheque
    (120 dBA); jet takeoff (125 dBA): thres-
    hold of pain (140 dBA).

How can I tell if my rig is too noisy?
    The  only reliable way is to have noise
    measurements  made  with a sound level
    meter;  do-it-yourself sound  level meters
    should be selected with care to avoid errone-
    ously high  noise readings. Many  mainte-
    nance facilities and component manufac-
    turers  offer  noise  measurement  service
    either as a courtesy or at a small, nominal
    cost Look  for advertisements for noise
    testing  and  noise  reduction  services  and
    equipment or  for  more  information  con-
    tact your regional EPA, Department of
    Transportation/Bureau of Motor  Carrier
    Safety Office, State or local motor vehicle
    office.

-------
              correcting
           noise problem
III have a noise problem, what's the most likely
cause?
    Exhaust  systems and cooling fans  are the
    most common high noise makers under sta-
    tionary and low speed conditions; at high-
    way speeds, tires frequently make the most
    noise. Other sources which can add to the
    total noise le\el are:
       • engine (mechanical)
       • air intake system
       • transmission
       • auxiliary engine equipment
       • brakes
       • aerodynamic flow

Isn't my stock muffler quiet enough?
    Not necessarily. Heavy-duty motor vehicle
    manufacturers  have not  had  to build to
    specific  noise  emission  standards. Muf-
    flers  have  often been selected  for  their
    low cost, appearance, size, and back pres-
    sure rather than for noise quieting ability.
    Check muffler manufacturers  or  distribu-
    tors;  they  can give you information about
    the noise  reduction capabilities and other
    operational  features  of  various  models
    when fitted to specific engines. You  may
    also want  to  investigate  the addition  of a
    turboch~'gcr  to jour vehicle. Recent in-
    dustry test results  show impressive noise
    reduction  in addition to fuel  savings  and
    improved  engine periorm.!ncc.
I understand cooling fans can cause high noise.
How can I tell if this is my problem, and what
can I do about it?
    Cooling fans can cause high noise. How-
     ever, maintenance  shops vsith noise testing
     facilities should be able to tell if this  is
     your problem.  If.  tor  example,  you in-
    stalled especially quiet  mulllers for >our
    particular engine and  the (ruck is still too
     noisy, it's likely your fan may need shroud
     repair,  adjustment  tor fan  tip clearance,
    blade repair or replacement, or possibly  a
    different blade  design  Remember,  modifi-
    cations to cooling >\sieins  should  not be
     done without expert adviee. You may \\ar.l
     to consider  a temperature  controlled  tan:
     resultant tuel  ami  eoM «-.IMIICS aic as im-
    pressive as  tneir noi-e rvuue:ion.
If my tires cause a noise problem at highway
speeds, what type tire should I replace them
with?

     This  is  a matter of judgment  based on
     your  operational  requirements. Generally,
     tread  patterns with  non-vented  cavities
     (suction cups) produce unusually high noise
     levels. This condition exists in pocket re-
     treads and can occur in other tread designs
     with tire wear. Tests show that rib tires are
     quieter than many other popular designs.
     Tire manufacturers and  dealers can give
     you guidance in  selecting quiet tires that
     meet your specific requirements.
           advantages of
        early  compliance
Are there any advantages if I comply with the
Federal noise standard before October 15,1975?
     Yes. You can benefit in a number of ways
     if you comply early. For example:
       1. You  can reduce the possibility of a
     fine for violation of motor vehicle noise
     regulations  in the  numerous  States  and
     local jurisdictions that have current laws.
     (State and local authorities are not required
     to wait  until  October 15 to enforce their
     noise standards.)
       2. You  can take  advantage  of courtesy
     noise measurements  now  offered  by many
     component manufacturers and various Fed-
     eral, State and local authorities.  An  un-
     hurried, thorough  investigation  of your
     principal noise problem  could save you
     dollars.
       3. You will have time to "shop around"
     for the best,  low-cost  solution to your
     problem.
       4. You  can reduce your costs of com-
     pliance by scheduling noise measurements
     and  corrective  work, if  needed,  during
     normal  maintenance periods  instead  of
     rushing to  meet a deadline.
       5. You  may save in  tuel consumption
     and cost and realize an  increase in avail-
     able power where noise  reduction steps arc
     taken that improve  engine breathing  and
     cooling fan efficiency.
       6. You can improve the public imago of
     truckers and  of the trucking industry.
       7.  You can  enjoy  greater driving com-
     fort, productivity and safety.

-------
             enforcement
  Who will enforce the regulations?

      The Department  of Transportation's  Bu-
      reau of Motor Carncr Safety will handle
      enforcement at the Federal level. State and
      local  jurisdictions  will also have enforce-
      ment  responsibility. The new law requires
      that all noise  regulations applied to motor
      vehicles  involved  in  interstate commerce
      be identical to the Federal regulation.
             information

                     &

              assistance

  Where  can I get  more information abort the
  regulation?,
      Contact any  office of the U.  S. Environ-
      mental Protection Agency or DOT/Bureau
      of Motor Carrier Saiety Olhcc  listed below
      by Regions served. Also  >our  local main-
      tenance shop,  motor vehicle  component
      manufacturer*  and  either  State or  local
      highway/vehicle divisions should be able
      to assist you.
                                                      Region 6  States: Arkansas, Louisiana, Okla-
                                                      homa, Texas, New Mexico
                                                      USEPA               DOT/BMCS
                                                      Room 1107            819 Taylor Street
                                                      1(00 Patterson Street     Fort Worth. TX  76102
                                                      Dallas, TX  75201

                                                      Region 7 States: Iowa,  Kansas, Missouri, Ne-
                                                      braska
                                                       USEPA
                                                       1735 Baltimore Street
                                                       Kansas Cit>, MO  64108
DOT/BMCS
P. O. Box 7186
Country Club Station
Kansas City, MO 64113
                                                       Region 8 States: Colorado,  Utah, Wyoming,
                                                       Montana, North Dakota, South Dakota
                                                       USEPA                DOT/BMCS
                                                       Suite 900               Room 151, Building 40
                                                       1860 Lincoln Street       Denver Federal Center
                                                       Denver, CO  80203       Denver, CO  80225

                                                       Region 9 States: Arizona, California, Nevada,
                                                       Hawaii
                                                       USEPA                DOT/BMCS
                                                       100 California Street      4'JO Golden Gate Avrnue
                                                       San Francisco. CA  94111  Box 36096
                                                                             San Francisco, CA  94102

                                                       Region 10 States: Alaska, Idaho, Oregon, Wash-
                                                       ington
                                                       USEPA                DOT/BMCS
                                                       Room lie              Room412, Mohawk Bldg.
                                                       1200 Sixth Avenue        222 S. W. Morrison Street
                                                       Seattle. WA  98101       Portland.  OR  97204
 Region 1 States: Connecticut. Maine, Massachu-
 setts, New  Hampshire, Rhode  Island,  Vermont
 USEPA                DOT/BMCS
 Room 2113             4 Normanskill Boulevard
 JFK Federal Building     DC I mar, NY 12054
 Boston, MA  02203

Region 2 Mates: New Jersey, New  York
USEPA                DOT/BMCS
Room 9076             4 Normanskill Boulevard
26 Federal Plaza         Delmar, NY   12054
New York. NY  10007

Region 3 States: Delaware. Maryland. Pennsyl-
vania,  Virginia,  West Virginia,  District  of
Columbia
USEPA
Room 225
Curtis Building
6th and Walnut Streets
Philadelphia. PA  19106
                      DOT/BMCS
                      Room 816-A
                      Federal Building
                      31 Hopkins Plaza
                      Baltimore. MD  21201
Region  4  Slates:  Alabama,  Georgia,  Florida,
Mississippi, North  Carolina,  South Carolina,
Tennessee, Kentucky
                      DOT/BMCS
                      Suite 200
USEPA
Koom 109
1421  Peachtree Street
Atlanta, GA 30309
                      1720 Peachtree Road N. W.
                      Atlanta, GA 30309
Region 5  States: Illinois. Indiana. Ohio, Michi-
gan, Wisconsin. Minnesota
USFPA                DOT/BMCS
203 South Dearborn Street l.i:<)9 South Dixie Hiphway
Chicago, IL 60n04      Homewood. IL  60430

-------
4. EFFECTS OF NOISE ON HEALTH
        AND WELFARE

-------
                                  SECTION 4

                EFFECTS OF NOISE ON HEALTH AND WELFARE
BACKGROUND
    Environmental noise is growing to the point where it is becoming a threat to our health
and welfare. A recent state and municipal survey,1  the results of which arc given in Table 1,
illustrates the major types of noise sources in our environment in order of their ranking by
237 respondents  This table reveals that 44% of the respondents identified motor vehicles,
including medium and heavy duty trucks, as the main source of noise in their neighborhoods.
    Long exposure to high levels of noise can cause hearing damage. However, there are
other effects of noise that result in annoyance and anxiety and distress. These include inter-
ference with speech communication, with telephone communication, with listening to TV
and radio, with listening to music, with concentration during mental activities and in the
performance of tasks, and with sleep and relaxation.
                                  TABLE I
   RANK ORDER OF STATE AND MUNICIPAL SOURCES OF NOISE PROBLEMS
    AS IDENTIFIED BY RESPONDENTS (237) TO THE STATE AND MUNICIPAL
                 NONOCCUPATIONAL NOISE SURVEY OF 1974
State and Municipal Sources
of Noise Problems
Cumulative Rank Order
1 . Motor Vehicles (General)
2. Aircraft
3. Industrial
4. Construction
5 Air Conditioners
Cumulative Total
And % Out of 237
No.
105
39
39
36
34
%
44%
16%
16%
15%
14%
 Unpublished United States bnvironmenlal Protection Agency "State and Municipal Noise Program Survey"
                                     4-1

-------
HEARING DAMAGE
     Our cars consist of three parts  outer, middle, and inner car (represented in Figure 1).
In the hearing process, sound waves enter the car, passing through the car canal to the ear-
drum, which transmits the sound as vibrations to three tiny bones called ossicles. It is here
that the acoustic reflex occurs, which protects the inner ear from loud sounds.  The acoustic
reflex actually is the tightening of the muscle in that area which therefore reduces the sensi-
tivity of the ear to sound, to the degree necessary. The ossicles then transmit the vibrations
to a fluid contained in the tiny structure of the inner ear, the cochlea. Within the cochlea
arc microscopic hair cells that wave back and forth in  response to the sound waves. It is the
energy impulses created by the movement of these hair cells that go to the brain, where the
impulses arc interpreted as sound.
     Hair cells can be damaged by sound waves that arc too intense  The duration of the
exposure and the frequency of the sound arc other factors that effect the risk of damage.  So,
although the acoustic reflex protects the inner ear from some loud sounds, other excessive
sounds arc transmitted to the inner car before the reflex can control the sound or when the
sound is sustained. In the case of an impulse sound, such as a gunshot, the reflex is virtually
useless as a defense
     When excessive sound occurs only  briefly, the damage may be temporary and the  hear-
ing loss is called a Temporary Threshold Shift (TTS).  However, if loud noises arc frequent or
sustained, the damage can be permanent; and the  hearing loss becomes a Permanent Threshold
Shift (PTS)

ANNOYANCE
     Environmental noise interferes with an extensive range of human activities   In Table 2
arc shown the activities specifically identified as being disrupted by surface vehicle noise.
The effect of such activity interference  is usually described as annoyance, which is a response
to auditory experience. Such annoyance has its roots in the unpleasant nature of some sounds,
in the ongoing activities disturbed or disrupted by noise, in the physiological reactions to
noise, and, as some research suggests, "Some reactions may be attributed to the  message
conveyed by the sounds, prior experiences and conditioning".2
     Everyone is familiar with noise that interferes with the understanding of speech  The
effect of different noise levels on communications among people is shown in Table 3. Other
factors that enter into speech communications and not shown in the table include  the qual-
ity of speech, the age of the listener, and individual hearing acuity.
     Noise also interferes with sleep   It can  cause an individual to arouse from sleep, prevent
an individual  from falling asleep, and disrupt the various sleep stages.  Noise can  shift the
sleep pattern  from the deep, dreamless stage to a lighter stage ^ It is possible, however, that
some types of sounds only disturb sleep when they arc unfamiliar.  Studies indicate that
individuals do become accustomed to some sounds and can sleep through such sounds.
"United States linvironmental Protection Agency, Public Health and Welfare Criteria for Noise. EPA Docu-
 ment No 550/9-73-002 (Washington, DC  US Government Printing Office), pp 1-3
     . pp  7-13
                                       4-2

-------
                      Semicircular
                       Canals
                                  Cochlea
Nerve
Fibers
Figure 1. Diagram of the Human Ear

-------
                                     TABLE 2
    ACTIVITIES OF RESPONDENTS DISTURBED BY SURFACE VEHICLE NOISE
                    (All Situations: Respondent's Usual Activity)
Category
Driving
Walking
Talking with people present
Working at home
Reading, writing, thinking
Sleeping
Other
Not relevant
Listening to TV, radio, records
Resting (awake)
Not ascertained
Total
No. of
Situations
47
16
42
12
80
155
13
179
92
35
22
693
Percentage
of Total
Situations
7
2
6
2
12
22
2
26
13
5
3
100
Other studies show that excessive noise reduces one's feeling of well-being, thereby causing
anxiety.  Noise on a regular, unrelenting basis can jeopardize physical and mental health.4
     The effect of noise on the performance of tasks has been studied extensively in the
laboratory and in actual work situations. These effects are often conceptualized in terms of•
     I.   Arousal - Arousal by noise can result in either detrimental or beneficial effects on
         human performance, depending on the nature of the task and the person's state
         prior to exposure.  For instance, noise might induce muscular tension that could
         interfere with needed delicate movements (i.e., typing).
     2.   Distraction - Distraction by noise can be considered as a lapse in attention or a
         diversion of attention from the task being performed  It is usually due to the
         annoying characteristics of noise.
     3.   Specific Effects - Specific effects include auditory  masking and muscular activation,
         such as startle responses to sonic booms
4Unitcd Sidles Environmental Protection Agency, kffects of Noise on People. EPA Document No  NTID300 7
 (Washington, DC  US Environmental Protection Agency, July 27, 1973), p 78
                                        4-4

-------
                     TABLE 3
NOISE LEVEL RANGES INTERFERING WITH COMMUNICATIONS
Communication
Method
Face-to-Face
Conventional
Intercom
Conventional
telephone
Loudspeaker
Noise Level Ranges, dB(A)
50-70
Speakers may
be separated
by more than
3 feet
Satisfactory
to difficult
Satisfactory
to slightly
difficult
Any loud-
speaker
satisfactory
70-90
Some effort
required for
good communi-
cation to be
maintained
over 1 to 3 feet
Unsatisfactory
Difficult
unsatisfactory
Good quality
speaker needed
for adequate
intelligibility
90-110
Maximum
satisfactory
communication
distance is
1 foot
Impossible
Press-to-talk
and acoustic
booth needed
Must be inside
helmet or ear
protector
110-130
Very difficult
to impossible
Impossible
Special tele-
phone needed
Inadequate
>230
Impossible
Impossible
Impossible
Inadequate

-------
ANXIETY AND DISTRESS
     Physical and mental changes occur as a response to noise. Noise can trigger mechanisms
that produce mental stress and stress-related physical changes, such as dilation and constric-
tion of blood vessels, rise in blood pressure, changes in heart rhythm, dilation of the pupils
of the eyes, and additional endocrine secretion into the blood stream.  Even the sound of a
heavy truck  passing on the other side of the street can produce these changes. While most of
these physical reactions are temporary, some of these effects may become chronic through
prolonged exposure to noise.  Although we may  not be currently aware of such changes,
such reactions occur daily as we encounter noise from traffic, machinery, household appli-
ances, lawnmowers, and typewriters.
     Physical difficulties related to stress include heart disease and cardiovascular dysfunction,
migraine headaches, gastrointestinal problems such as ulcers and indigestion, allergies, endo-
crine problems, and metabolic changes.  Since our bodies can interpret noise as stress, there
is increasing evidence that noise is a contributing factor in the rate of occurrence of these
stress-related diseases.
     Stress is also a factor m mental illness.  While environmental  noise alone probably does
not produce mental illness,  the continual bombardment by noise on an already depressed
person may be harmful.  Strong evidence to support this thesis is provided by a  1969 compara-
tive research study of persons living adjacent  to London's Heathrow Airport. Results re-
vealed that persons living in this noisy environment had a significantly higher rate of ad-
mission to mental hospitals than those living in a quieter environment.
     Environmental noise is a threat to our health and welfare.  It must, therefore be abated
and controlled
                                        4-6

-------
5. PRINCIPLES OF SOUND

-------
                                   SECTION 5

                            PRINCIPLES OF SOUND
     How is sound produced, what are its characteristics and how is it measured? The following
discussion presents the principles of sound in answer to these questions.
     Sound is produced when a vibrating object (sound source) causes minute variations in
atmospheric pressure by alternately compressing and decompressing air molecules to vibrate.
These minute variations are called sound pressure.
     The vibrating air molecules adjacent to the sound source also push and pull against their
neighboring air molecules, and they in turn against theirs, thus causing the sound to travel
away from the source. This movement of sound is called a sound wave, because of the
similarity to the wave motion produced by dropping a pebble in water. When a sound wave
reaches the ear, it imparts its vibrating motion to the ear drum, which in turn sets several
other ear mechanisms into motion before the sound is heard.
     Sound has three major components: amplitude, frequency, and duration. Amplitude
refers to how loud or soft a sound is,  its volume. The amplitude of a sound is determined
by the distance that  the sound source moves back or forth when vibrating. For example,
the harder you hit the surface of a drum, the further that surface will move in and out; and
the louder that the sound will be.
     Frequency is determined by the number of times the sound source vibrates backward
and forward per second. This is commonly referred to as the number of cycles per second
(cps), or  the number of Hertz (Hz). A string that undergoes 256 complete oscillations in
1 second (middle C) produces a vibration of the same frequency in the surrounding air and
in the eardrum of an observer in the sound  field. This assumes that the source and the
observer  are at rest with respect to the medium, the usual assumption in room acoustics.
Frequency is a physical phenomenon; it can be measured by instruments, and it is closely
related to, but is not the same as pitch - a  psychological phenomenon. Figure 1 shows
the piano keyboard  and the relative ranges  in frequency of male and female voice types.
The  faster a source vibrates, the higher the  frequency of the sound produced.  The young,
healthy human ear can detect frequencies from 20 to 20,000 Hz, which is often called the
audible, or sonic, range.  The terms ultrasonic and infrasonic refer to sound frequencies
that  are higher and lower, respectively, than the audible frequency range of 20 to 20,000
Hz.  The vast majority of audible sounds are actually composed of many frequencies, just
as a chord played on a piano is actually composed of several notes truck simultaneously.
     The third major component of sound  is the duration, i.e., the time period during
which the sound can be heard. Duration is related and dependent upon the length of time
the source vibrates.
                                      5-1

-------
    125
                   250                        500                        1000

Figure 1.  Piano Keyboard  Showing Human Voice Octave Ranges
      The relative amplitude (loudness) of sound, or sound pressure level is measured in

decibels (dB), just as distance can be measured in miles (see Figure 2).  Zero on the decibel

                                              DCC'CELS
                                             RE ?0|iN/m3
                             THRESHOLD OF f\\N	1JO— HYDRAULIC PRESS (3-)
                                                I	SIREN AT IIOO'I
                                 JET PLANE 150') —130

                           AUTOMOBILE HORN 13') —1JD  ROCK R ROLL BAND
                                                I	CHAIN SAW 150')
                                               110

                                                I	UNMUFFLEOSNOVvMOBILEISO'l
                           DCBAIRLINEn Hi SIDE)—100

                              MOTOR CYClc (50) ._.o'0

                           ARH*CccEuVuf G DO! ^l" MUFFLED SNOWMOBILE isoi
                                                10 — INSIDE CAR AT ISC MPHI


                           VACUUM CLFANCH UO'I	70 — CONVERSATION I3JI
                                                DB—PRIVATE BUSINESS OFFICE
                                SOFT WHISPER (5'l
                                                  ) — STUDIO FOR SOUND PIC1URES
                          THRESHOLD OF HEAR^G   . I
                           YOUTHS - 1000 -SOOO c,'s    I °

                     Typical A weirhted raund levels mc3iuicd Kiih o uunH lael meter  These valuos arc
                     taken from ih» hl»ratu>c Sound Ic'.cl n-.2.'sjrup-nis 11 'e only r'rt ol the inlormaiion
                     uuially i:   »?rv 'o I'and'c TL ro ("Cl1*1 n^:  .niul •''? o icn :uii|J iiinur'l by pnzl'^is ol
                     the noiS25p:rlra

                          Figure 2.  Typical A-Weighted Sound Levels
                                               5-2

-------
scale indicates the lowest sound the unimpaired human ear can detect. However, there is a
difference between sound and distance measurements.  The decibel scale of measurement
is logarithmic, while the scale of miles is arithmetic. This means that decibels cannot be
directly added or subtracted. For instance, if two trucks each drove 100 miles, the total
number of miles driven by the two trucks combined is 200.  But, if the sound level of each
of these trucks is 85 dB alone, when they are driven side by side their combined sound level
is 88 dB, not 170 dB (refer to Figure 3). Furthermore, since decibels are logarithmic, 10
decibels on the decibel scale are 10 times more intense than one decibel; 20 decibels are
100 times more intense (1 Ox 10); 30 decibels are 1,000 times more intense (1 Ox 1 Ox 10).
                       \
                          \
                              \
                   I   2   3  4   5   6   7   8   9  10  11   12  13  14   15
                         DIFFERENCE IN dB BETWEEN TWO LEVELS BEING ADDED

                          Two noises of approximately equal sound levels give
                         a total leading 3dB higher than either noise measured alone
                              for instance  85 dB + 85 dB = 88 dB

                                     Figure 3.

     This more complicated  measurement scale is used for the following two reasons:
     1.   The range of sound pressures that can be detected by the human ear have a ratio
         of one million to one if measured on an arithmetic scale.  By using a logarithmic
         scale this tremendous range is condensed into a scale that  ranges from 0 dB to
          120dB.
     2.   The human ear tends to react to sounds in a logarithmic manner. That is to say,
         the ear is capable of detecting a small increase in sound pressure when the
         original sound pressure is low. But when the original sound pressure is high, it
         takes a much larger increase in sound pressure before the ear can detect the
         change.  For example, your ear can detect the difference in sound pressure level
                                       5-3

-------
         between one truck idling and two trucks idling side by side, but it cannot hear
         the difference in sound pressure level between 100 trucks idling side by side and
         101 trucks idling side by side.
     Frequency analysis is a method of measuring sound that provides information regarding
the sound's frequency composition.  To represent properly the total noise of a noise source,
it is usually desirable or necessary to break the total noise down into its various frequency
components; that is, how much of the noise is low frequency, how much high frequency
and how much is in the middle frequency range.  This is essential for any comprehensive
study of a noise problem for two reasons:
     1.   People react differently to low frequency and high frequency noise (for the same
         sound pressure level, high frequency noise is much more disturbing and is more
         capable of producing hearing loss than is the case for low frequency noise).
     2   The engineering solutions to reduce or control noise are different for low fre-
         quency and high frequency noise (low frequency noise is more difficult to con-
         trol, in general).
     It is conventional practice in acoustics to determine the frequency distribution of a
noise by passing that noise successively through several  different filters that separate the
noise into 8 or 9 octaves on a frequency scale. Just as with an octave on a piano keyboard,
an octave in sound analysis represents the frequency interval between a given frequency
(such as 250 Hz) and twice that frequency (500 Hz in this illustration).
      125
  250
Middle "C"
                                                       500
                                                    1000
                 Figure 4. Piano Keyboard Showing #3 Octave Range

     In conducting noise studies it is often necessary to determine the distribution of sound
 pressure with frequency because hearing loss, annoyance, speech interference, sound absorp-
 tion, etc., all vary with frequency. This can be done by measuring the sound pressure in
 frequency bands of various widths.  Those most commonly used are the octave, half-octave,
 and third-octave bands. An octave band is a frequency interval in which the upper frequency
 is twice the lower frequency, such as 150 to 300 cycles per second or 1200 to 2400 cycles
 per second.
     Other methods of measurement which consider sound frequencies are the A-, B-, and
 C-weighted  sound levels. Sound level meters are usually equipped with weighting circuits
 that tend to represent the frequency characteristics of the average human ear for various
                                       5-4

-------
sound intensities. Hence, overall readings are sometimes taken with A-scale or B-scale or
C-scale settings on the meter.  The A-scale setting of a sound level meter filters out as
much as 20 to 40 dB of the sound below 100 Hz, while the B-scale setting filters out as
much as 5 to 20 dB of the sound below 100 Hz.  The C-scale setting is reasonably flat
with frequency, i.e. it retains essentially all the sound signal over the full overall frequency
range.  For several years the A-scale and B-scale readings were  held in disfavor because they
do not provide any knowledge of the frequency distribution of the noise, but there is a
revival  in the use of A-scale readings as a single-number indicator of the relative loudness
of a sound as heard by the human  ear.  (The new Federal interstate motor earner regula-
tions utilize  the A-scale.)  It is very important, when reading A-, B- or C-scale sound levels,
to positively identify the scale setting used.  The resulting values are called sound levels and
arc frequently identified as dB(A), or dB(B) or dB(C) readings.  Note that these readings do
not represent true sound pressure levels because some of the actual signal has been removed
by the  weighting filters.
     Many sound measures take duration into account. These measures are commonly
referred to as sound  exposure measures. Sound levels that vary over a time period, such as
those produced by highway traffic, can be measured by the equivalent steady A-weighted
sound level, having the same energy content as the fluctuating sound level.  This steady
A-weighted sound level is called the Equivalent Sound Level (Leq). Sometimes the number
of hours over which  the equivalent sound level is calculated is  put in parentheses after the
symbol. For example, an equivalent sound level of 60 dB determined over an eight-hour
period  might be stated as:  Leq(8) = 60 dB.  This measure is based on  the equal energy
hypothesis that the degree of harm done to hearing is a function of the sound energy.
     The Day-Night  Sound Level (Ldn) is another measure of sound exposure. It is equal
to the Equivalent Sound Level calculated over a 24-hour period, with  the exception that a
10 dB increment is added to the equivalent sound level occurring during the night-time
hours of 10 p.m. to 7 a.m. This night-time increment is added because sounds occurring
during  those hours may interfere with sleep.
                                      5-5

-------
6. MAJOR VEHICLE NOISE SOURCES
 AND NOISE CONTROL MEASURES

-------
                                    SECTION 6

                        MOTOR VEHICLE NOISE SOURCES


     The noise level an enforcement officer will  measure for a given motor vehicle will not
be just from the exhaust system or from the cooling fan, but rather will be the sum of the
individual noises from several sources on the vehicle.  In Figure 1 are shown the known
sources of noise in a truck, however investigations have shown the major ones generally are:
     •    Exhaust System
     •    Engine Cooling Fan
     •    Engine (Mechanical)
     •    Engine Intake System
     •    Tire/Roadway Interaction
     The first four souces listed are of particular importance for motor vehicles traveling at
low speeds (less than 35 mph) or under stationary run-up conditions. At higher speeds
(35 mph and above), tires become the predominant noise source.
     A brief discussion of the major noise sources, the noise reduction techniques, and the
estimated costs are presented is the following subsections.

EXHAUST SYSTEM
     Exhaust noise is created when engine exhaust gases cause oscillations within the
exhaust pipe. These oscillations are radiated to the atmosphere at the tail pipe. The noise
is a function of engine type, induction system, and other associated parameters.  In addition
to being radiated from the end  of the tail pipe, exhaust noise is transmitted through the
exhaust pipe and muffler walls. Noise is also produced by the application of engine brakes
(on trucks so equipped), which assist the wheel brakes by producing a retarding force on the
engine. Typical exhaust noise levels range from  77  to 85 dB(A) at  50 ft, independent of
vehicle speed, and can be much higher in poorly maintained trucks.
     Although the exhaust system is a major noise source, significant noise level reductions
can be achieved fairly easily. A good muffler is mandatory, and for maximum quieting a
double-wall, or wrapped muffler, can be used to reduce radiation through the walls. Con-
sideration can also be given to wrapping the tail  and exhaust pipes with insulation. The
system must be free from leaks and should be attached by isolation mounts to the truck
frame. The location of the muffler in the overall system, the exhaust pipe length and
diameter, and the tail pipe length and diameter should be considered, although these factors
assume a gradually lessening importance as the noise reducing capability of the muffler
increases.  Muffler specifications and suggested exhaust system configurations are currently
                                        6-1

-------
       A.
       B.
       C.
       D.
       E.
 Major Noise Sources
Engine (Mechanical)
Engine Cooling Fan
Engine Exhaust
Air Intake System
Tire/Roadway Interaction
F.
G.
H.
I.
 Other Sources

Transmission
Ancillary Equipment
Aerodynamic Flow
Brakes
                            Figure 1. Truck Noise Sources
offered by major muffler manufacturers for almost every engine, although no muffler exists
that is the best for all types of engines.
     From motor vehicles equipped with the best available mufflers, exhaust noise alone
typically ranges from 72.5  to 80.0 dB(A) at 50 ft. These mufflers provide attenuation of
from 9.5 to 27.0 dB and are installed on some new trucks as standard equipment.
     A good quality muffler typically costs from $35 to $45; and, since the installation is
simple, many trucking companies do it themselves. Installation costs for either single or
dual systems are about $ 15. For maximum effect, it is necessary to replace existing flexible
exhaust pipes with rigid pipe and slip joints at a cost of about $45 per side, including labor.

ENGINE COOLING FAN
     Trucks generally use axial  fans to draw air through a front-mounted radiator. The air
cools water, which in turn cools the engine. Fan noise is the result of air flow irregularities
and is partially governed by the proximity of shrouds, radiators, grills, and radiator shutters.
The noise produced by the fan  is related to fan tip speed. Most diesel engines on heavy
trucks reach maximum rated horsepower at about 2100 rpm. At this speed, the fan can be
a major contributor to the overall truck noise level. Typical heavy vehicle fans alone exhibit
noise levels in the range of 78 to 83 dB(A) at 50 ft at rated engine speed.
                                        6-2

-------
     Since noise from a cooling fan increases with its rotational speed, it is possible to reduce
the noise while maintaining the same air flow (to satisfy the same cooling requirement) by
using a larger fan turning at a slower speed.  In many cases this may require the installation of
a larger radiator, which would result in an expensive modification to the front of the engine
compartment.
     It is often possible to install a fan blade that produces less noise while at the same time
providing adequate cooling.  Most existing fans are stamped out of metal, with equal spacing
between the blades, and they are driven at a predetermined fixed ratio of fan-to-engine speed
by a belt-driven pulley. This type of fan was not originally designed to be quiet, nor is it
particularly efficient in cooling.
     Trucks are designed to be able to cope with heat rejection at maximum  engine power
with little or no ram air. Since ram air increases with vehicle speed, fans become less impor-
tant at higher vehicle speeds and could be slowed or stopped in many instances.  The critical
cooling requirement occurs when the vehicle is moving slowly in a low gear while the engine
is developing full horsepower (e.g., when pulling a heavy load up a  long grade).  Trucks,
unlike automobiles, usually do not have an overheating problem when the vehicle is stopped
and the engine idles at low rpm. Given these characteristics, it is possible for a truck to have
a fan that does not operate continuously.
     Fan noise can frequently be reduced by as much as 7 to  12 dB by  replacing the standard
fan with a more sophisticated one. Overall vehicle noise can be reduced by about 1 dB in
some cases by  incorporating a venturi-type shroud with a small tip  clearance.
     Fans are now available that operate only when additional engine cooling is required and
that idle when the cooling due  to ram air flow is sufficient. A typical fan of this type has
cither a thermostatically controlled mechanical clutch or a viscous  fluid clutch. The viscous
fluid clutch permits the fan to rotate at reduced  speeds, and the thermostatically controlled
mechanical clutch permits the fan to stop completely when it is not needed.  Fans utilizing
these clutches are from 3 to 10 dB quieter than conventional fans.
     The replacement of a standard stamped fan with a more sophisticated one will cost
between S40 and $45, including installation. Incorporation of a venturi-type shroud will
cost about $45, including installation.
     A viscous clutch costs about $240, including about $15 for the suggested fan blade. A
thermostatically controlled, mechanical clutch, including the necessary  fittings, costs from
about $285 to $360. plus $40 to $50 for installation.

ENGINE (MECHANICAL)
     Mechanical noise in internal combustion engines is caused by the combustion process,
which produces the  high gas pressures necessary  to force the piston down the cylinder to
turn the crankshaft. The rapid rise in cylinder pressure immediately following combustion
creates mechanical vibrations in the engine structure that are transmitted through the
cylinder walls, oil pan, rocker arm, and covers. Some of this vibration is subsequently
radiated into the atmosphere as acoustic energy.
                                        6-3

-------
     Gasoline engines initiate combustion with a flame that spreads smoothly throughout
the cylinder until the fuel-air mixture is burned. Diesel engines, however, rely on much
higher compression ratios (about 17:1  rather than 9:1) to produce spontaneous combustion.
This higher compression ratio causes a more rapid change in pressure in the cylinder, which
in turn results in increased engine vibration and, thus, higher noise levels than those associ-
ated with gasoline engines.  As a result, the mechanical noise levels of diesel engines often
are as much as 10 dB higher than those of gasoline engines. The engine mechanical noise
contribution in typical diesel-powered trucks is on the order of 78 to 85 dB(A).
     Turbochargers are often used to increase the pressure of the intake air.  This reduces
the pressure fluctuations in the engine and, in turn, lowers the engine noise level.
     There are generally two kinds of retrofit method for reducing engine noise:
     1.   Modification of certain exterior surface covers.
     2.   Installation of acoustical absorption material and acoustical barriers in the engine
         enclosure.
Engine noise reduction kits suitable for a limited number of engine models are available
from a few major engine manufacturers.  These kits consist of various acoustically treated
panels and covers and provide a reduction of about 3 dB in engine mechanical noise (as
opposed  to total vehicle noise level).
     Noise reduction kits, in limited production at the time of this writing, cost between
$50 and  $ 100 for materials. However, these kits have not yet undergone complete dura-
bility testing.

AIR INDUCTION SYSTEM
     Induction system noise is created by the opening and closing of the intake  valves; this
action causes the volume of air in the system to pulsate. The associated noise levels depend
upon the type of engine, the engine operating conditions, and whether the engine is turbo-
charged or naturally aspirated. Typical intake noise levels vary from  70 to 80 dB(A).
     The state of intake noise reduction  technology is similar to that of exhaust noise
reduction.  Major manufacturers are able to provide assistance in proper selection of air
intake systems for all popular engine models.  Retrofitting the intake systems of in-service
trucks consists of replacing older air cleaners with modern quality, dry element  air cleaners.
     Intake cleaners and silencers are manufactured largely by the major muffler manufac-
turers and are readily available at costs ranging from $ 100 of $ 130.

TIRES
     Heavy motor vehicle tires for highway  use can be classified into two categories - rib
tires and  crossbar tires (also known as lug or cross-rib tires).  Rib tires look like automobile
tires, with the tread elements oriented circumferentially around the tire. This is the most
common type of truck tire and can be used  in all wheel positions.  Rib tires are  used almost
exclusively on steering axles because of their superior lateral traction and uniform wear
characteristics.  Crossbar designs have the tread elements oriented transversely to the plane
                                        6-4

-------
of the tire. Many trucking companies prefer to use crossbar tires on drive axles, since they
provide up to 60 percent greater initial tread depth, and, thus, greater mileage before recap-
ping.
    The noise-generating mechanisms of tire/roadway interaction are not completely
understood. It is known that the entrapment and release of air from the tire tread cavities
produces noise. Also, it appears that the vibration of the tire contributes to the total noise
level.  However, the effect on noise levels of the large lugs on  crossbar tires and of the road
surface are not well quantified.  Basically, all the available noise information has been
obtained experimentally, and tire manufacturers do not appear to be close to any major
breakthrough that would result  in quieter crossbar tire designs.
     Extensive measurements of the noise level produced by tires mounted on the drive
axle of a truck-tractor have been conducted by the National Bureau of Standards and the
Department of Transportation (see Figure 2).  Typical values of the noise level measured at
50 ft are 68 and  73  dB(A) at 35 mph for new rib and crossbar tires, respectively, on a con-
create roadway.  At 55 mph, these levels typically  increase to 75 and 83 dB(A).
     Test data also indicates that some retread tires, having a tread composed largely of
pockets that are  not vented either around the tire or to the side, produce excessive noise
levels by allowing air to be trapped, compressed, and subsequently released as the pockets
pass through the footprint area  of the tire.
     In general, rib  tires produce lower noise levels that either the crossbar (by approxi-
mately 9 dB) or suction cup (pocket) retread (approximately 23 dB) tires.
     Tire wear also  affects noise level, noise increases until a maximum level is reached
when the tread is approximately half worn. Tests  show increases of about 5 dB and 8 dB
for rib and crossbar tires, respectively.
     Finally, tire loading can  also influence tire noise level. Tests have shown increases of
2-4 dB in rib tire noise levels dB as a result of loading the test vehicle to its limit. Identical
tests of crossbar and pocket retread tires showed increases of 7 to 9 db.
     Considerable high speed noise reduction can be obtained through the replacement of
suction-cup (pocket) retread tires by crossbar tires at no increase in cost or with loss of
performance.  Additional noise  reduction can be realized through proper tire inflation and
vehicle loading and  through a proper tire replacement schedule.
     Since crossbar tires begin to dominate overall vehicle noise levels at speeds in excess
of about 45 mph, the high-speed standard of 86 dB(A) might suggest the elimination of
virtually all  crossbar tires.  However, performance  and  safety  requirements must be con-
sidered.  Therefore, a 4 dB margin has been added to the 86 dB(A) low-speed standard,
resulting in a 90 dB(A) high-speed standard to account for tire noise.  Experience indicates
that it will be necessary to eliminate some crossbar tires on heavy trucks having a large
number of axles. However, it should still be possible for these trucks to operate with cross-
bar tires on  the drive axles.
     For those trucks that must be changed from crossbar to rib tires in order to comply
with the standards, a small cost penalty may result.  Under a  strategy of recapping each tire
only once, the cost difference between crossbar and rib tires is approximately $0.23 per
                                         6-5

-------
                         Speed, KM/Hr

                  60     70      80
                                90     100
100
                                                Pocket
                                                Retread
                                                          Cross-Bar
                                                            Rib
30
                      40           50
                          Speed, mph
  Figure 2. Peak A-Weighted Sound Level, as Measured at 50 Feet,
   Versus Speed for a Loaded Single-Chassis Vehicle Running on
        a Concrete Surface.  Various Types of New Tires are
         Represented on the Graph.  These Were Mounted
                       on  the Drive Axle
                             6-6

-------
thousand miles.  For a single-drive-axle truck, this represents a cost difference of less than
$0.001 per mile.
     It appears that per-mile cost differentials between tires having different types of tread
may depend on tire composition and terrain as well as on motor carrier recapping policies.
A comprehensive study of cost differentials associated with the use of truck tires of different
types is being conducted by EPA.

SUMMARY
     There is a practical limit to noise level reductions that can  be achieved on motor vehicles
through retrofit actions. EPA studies indicate it is not cost-effective and often not feasible
to quiet in-service motor vehicles below that noise level that characterized them when new.
For instance, there are trucks in the existing fleet with certain diesel engines that are too
noisy to be sold in jurisdictions that currently enforce an 86 dB(A) noise emission standard
measured at 50 feet. Although these engines are being phased out of use in new trucks, they
represent an obstacle to setting limits lower than 86 dB(A) for interstate motor carrier
regulations, when best available technology and cost of compliance are taken into account.
     EPA believes a low speed noise level of 86 dB(A), a high speed noise level of 90 dB(A),
and a stationary  noise level of 88 dB(A) are all achieveable with available technology for
almost all medium and heavy duty trucks in the existing fleet and buses, since both types
of vehicles use the same engines and tires.
     Table  1 indicates that nearly all trucks currently exceeding 86 dB(A) require only the
addition or replacement of a muffler to be in compliance. Manufacturers have testified
publicly that adequate mufflers can  be available in sufficient numbers of permit compliance
of all motor vehicles needing mufflers within year of promulgation of the Interstate Motor
Carrier Regulations.
                                        6-7

-------
                        TABLE I
APPROXIMATELY COSTS TO RETROFIT MOTOR VEHICLES TO VARIOUS
           NOISE LEVELS (ACCORDING TO SAE J336a)
Noise Level Typical Estimated Cost
dB(A) @ 50' Treatment Per Truck
% Trucks Exceeding
Specified Noise Level
Requiring Component
Change

90 Exhaust1 50-105
100%

Total $50-$105
88 Exhaust1 50-105
Fan2 40-45
100%
5%

Total $90-$150
Exhaust3 100
86
Fan4 85-90
Intake5 100-130
100%
10%
5%

Total J280-$310
Exhaust6 100-200
84 Fan? 650-740
Intake5 100-130
Engine8 80-130
100%
50%
25%
25%

Total $930-$! 200
1. Muffler and labor—single or dual system.
2. Replaced fan blade.
3. Mean cost for muffler and labor, plus additional cost for some trucks
requiring replacement of flexible tubing, etc.
4. Replaced fan blade and added shroud in some cases.
5. Average cost of dry element air cleaner with built-in silencer.
6. Muffler and replacement of feasible pipes— single or dual system.
7. Viscous fan clutch and new fan blade in conjunction with shroud,
Thermostatically controlled clutch.
8. Partial engine kit plus installation.
                         6-8

-------
7. ENFORCEMENT

-------
                                    SECTION 7

                                  ENFORCEMENT
     Section 18 of the Noise Control Act of 1972, requires the Secretary of Transportation,
;it'ter consultation with the EPA Administrator, to promulgate regulations to ensure compli-
ance with applicable standards promulgated by EPA under section 18. "The Secretary of
Transportation shall carry out such regulations through the use of his powers and duties of
enforcement and inspection authorized by the Interstate Commerce Act and the Department
of Transportation Act."
     The authorities just cited have been vested in the Bureau of Motor Carrier Safety
(BMCS), which is part of the Federal Highway Administration, Department of Transportation.
     The basic power and duties referred to in section 17(b) of the Noise Control Act are
derived from section 220 of the Interstate Commerce Act.  Section 220 requires motor
carriers to submit all properties including vehicles, documentation, and offices if necessary,
for inspection or examination by designated agents of the Federal Highway Administration.
Using this  authority, BMCS safety  investigators routinely conduct safety compliance checks
of both drivers and equipment at various roadside locations, truck weigh stations, and ports
of entry throughout the country.  These inspections arc not limited to specific times of day,
seasons of the year, or locations; such inspections arc usually conducted in close cooperation
with state  police and other interested state and local authorities.
     Enforcement of EPA's exterior noise standards will  be effected as part of this existing
safety inspection program. However, great emphasis will be placed on independent enforce-
ment by state and local authorities in those jurisdictions having appropriate noise ordinances.

TEST CONDITIONS
     The EPA standard specifies three different operating conditions that can be used to
ascertain the level of noise meitted by a motor vehicle. Each test carries with it a maximum
acceptable noise level as follows:
     88 dBA   -  stationary run-up
     86 dBA   -  low speed passby (speeds 35 mph or less)
     90 dBA   -  high speed passby (speeds above 35 mph)
     In addition  the standard calls for visual inspection of exhaust systems to look for  noise
producing defects or modifications and for visual inspection of tires for pocket (non-vented
cavity) tread designs. The principal intent of these three different test conditions and visual
inspections is to provide maximum enforcement flexibility.
                                       7-1

-------
     Although the test conditions and their respective maximum noise levels differ, they are
designed to be equally stringent, and they exhibit high correlation among test results.

TEST PROCEDURES
     A brief description of the test methodologies to be used for the EPA noise emission
standard are presented below (for detailed descriptions sec DOT Proposed Compliance Pro-
cedures A9CFR 325 appended hereto):
     1.   Stationary Run-up Test - The stationary noise test is the quickest way to determine
         the exterior noise level of a vehicle.  It is expected that this test will be used ex-
         tensively in vehicle safety check lanes and vehicle weigh stations.  The test is also
         useful to the licet owner who wants to spot check vehicle noise levels.
         The test involves locating the vehicle within an open site. The ground surface
         within the test site should  be covered by concrete or other similar hard surfaces.
         The microphonc/observor is located 50 feet from the longitudinal centcrlmc of
         the vehicle, and, the vehicle engine is accelerated, at wide open throttle, to its
         maximum governed rpm.  The  maximum sound level is then measured with either
         a Type  I or II meter, during this engine runup procedure  Two or more tests of
         this type arc conducted until two readings are obtained within 2 dBA of each
         other  These two sound levels  are then arithmetically averaged to obtain the
         noise level for the test vehicle.  The maximum allowable noise level permitted
         under these  test conditions is 88 dBA.
     2   Low Speed Passby Test - A typical low speed passby test will probably consist of
         location of the microphone of a Type  I or II sound level meter (or other similar
         sound measuring system) at a distance of 50 feet from the ccnterlme of the test
         vehicle's path of travel, as shown in B-l.  Sites for these enforcement  measure-
         ments are generally picked to be soft sites, that  is, sites having some kind of
         grass or similar short-cut vegetation ground cover between the roadway and loca-
         tion of  the microphone. Measurements are made with the vehicle passing the site
         at any speed less than  35 mph  under any condition of power and generally with-
         out  the prior knowledge of the driver.  Due care is taken to assure the absence
         of reflecting surfaces or other vehicles that might contribute extraneous noise to
         the overall noise reading.  The  maximum allowable sound level under these test
         conditions is 86 dBA.  The posted speed limit at the test site for this testing condi-
         tion must be 35 mph or less.
     3.   l/igh Speed Passby Test - The high speed passby test procedure and instrumenta-
         tion setup are basically the same as those for the low speed passby test, with the
         exception that measurements arc taken at sites having a posted speed  limit m
         excess of 35 mph.  The maximum allowable measured sound level under these
         test conditions is 90 dBA.
     In the initial stages, BMCS will be conducting all or most of its noise inspections using
the stationary test. It  is anticipated that  passby tests, without the knowledge of the driver,
will be the principal method used by state and local  enforcement agencies.  The Federal
Highway Administration may conduct high and low speed passby tests at a  later date
                                       7-2

-------
VIOLATIONS & PROSECUTION
     If a vehicle is found by BMCS investigators to be in violation, the driver will be given a
written report of the inspection and will be instructed to submit this report to the motor
carrier.  The report form includes a place on which the motor carrier certifies the corrective
action he has taken.  He must return the report to the Federal Highway Administration within
15 days.  State and local enforcement agencies are not obligated to follow this procedure
and may issue formal citations requiring court appearance and fines.
     It is not expected or intended that every inspection revealing a noise level exceeding
that permitted by the regulation will result in any kind of a prosecution or other enforce-
ment action. However, in those instances in which a motor carrier continues to use a vehicle
that exceeds the noise level, or in which  he falsely certifies that corrective actions or repairs
have been made to a vehicle, prosecution can result.  The case would be developed against
the motor carrier  operating the vehicle or, in the case of leased vehicles, possibly against the
owner of the vehicle if he were a deliberate party to the continuance of the violation.
     Penalties and fines will be both (1)  state and local and/or (2) Federal. The penalties
and fines levied as a result of state and local laws will vary from location to location. In the
case of Federal  prosecution, the individual is subject to a fine or as much as $25,000.

SUMMARY
     The motor carrier safety staff of the Federal Highway Administration will be responsi-
ble for determining compliance with provisions of the regulations under the Noise Control
Act. Although  this responsibility will not be a fulltime occupation for these safety investi-
gators (a portion of their time must be spent in performing safety related activities), it will
be significant when coupled with the enforcement of DOT's in-cab noise regulation. Further,
as a part of the  Noise Control Program, it is anticipated that many state and local jurisdictions
will adopt the Federal Noise Control Regulations. It is planned that BMCS and EPA personnel
will assist in the training and orientation of state and local people who will then make the
required noise inspections and will administer the regulations under the laws of their respec-
tive jurisdictions.
     In the final analysis, a well rounded and cooperative Federal, state and local program
should result, which will control the level of noise emitted by motor earner transportation
vehicles.
                                        7-3

-------
FRIDAY, FEBRUARY 28, 1975
WASHINGTON, OjC.

Volume 40 • Number 41

PART II
 DEPARTMENT OF
TRANSPORTATION
     Federal Highway
      Administration
  INTERSTATE MOTOR
    CARRIER NOISE
 EMISSION STANDARDS
  Proposed Compliance Procedure*

-------
8658
          DEPARTMENT OF
         TRANSPORTATION
     Federal Highway Administration
          [49 CFR Part 325]
   (Docket No MC-62, Notice No 76-4]

 INTERSTATE  MOTOR  CARRIER  NOISE
        EMISSION STANDARDS
      Compliance  with Standards
  The Director of  the  Bureau of Motor
Carrier  Safety  is issuing this notice of
proposed rule making for the purpose of
inviting interested persons to comment
on the text of proposed regulations estab-
lishing  methodologies  for  determining
whether commercial motor  vehicles con-
form to the Interstate  Motor  Garner
Noise Emission Standards of the Environ-
mental  Protection  Agency.
            INTRODUCTION
  On October 21,  1974, the Acting Ad-
ministrator of  the Environmental Pro-
tection  Agency issued  flnal regulations
establishing standards for maximum ex-
ternal noise emissions of motor vehicles
having a gross vehicle weight rating or a
gross combination weight rating of more
than 10,000 pounds that are operated by
commercial  motor carriers engaged in
interstate  commerce  (39  PR  38208).
Those regulations were Issued under the
authority of section 18 of the Noise Con-
trol  Act of 1972 Section 18 of the  Noise
Control Act of 1972 also directs the Sec-
retary of Transportation to promulgate
regulations to ensure compliance with the
Environmental   Protection   Agency's
standards The Secretary is required to
carry out the regulations through the use
of his powers and duties of enforcement
authorized by the  Interstate  Commerce
Act and the Department of Transporta-
tion  Act. Those two statutes vest in the
Department of Transportation the re-
sponsibility  for Issuing and  enforcing
the   Federal   Motor  Carrier  Safety
Regulations.
  The objective of  the regulations under
consideration at this tune is to prescribe
the manner in which commercial motor
vehicles will be Inspected and examined.
and  their performance  will  be monitored
and measured, to determine whether they
conform to  the EPA standards. Those
standards become effective on October 15,
1975 and, as noted above, are applicable
only to motor vehicles  with a QVWR or
a GCWR of more than 10,000 pounds,
which are operated by Interstate motor
carriers. The Department of Transporta-
tion  has no statutory authority to alter
or amend the EPA noise emission stand-
ards or to decline to issue procedures for
their full enforcement. Therefore, the
Director does not propose  to reopen for
consideration questions relating to the
bases of the EPA noise emission stand-
ards  which were  fully considered and
acted upon by EPA during  the rulemak-
ing  proceeding in  which It promulgated
 the interstate Motor Carrier Noise Emis-
sion Standards. Those questions Included.
but were not limited to, (a) denning the
 "best available technology"   consistent
          PROPOSED RULES

with the motor carrier Industry's ability
to comply with the standards;  (b)  cost
of compliance: (c) Federal preemption
of State and local noise laws and ordi-
nances;  (d) applicability of  the stand-
ards to various weight classes of vehicles;
and  (e) the appropriate definition of an
Interstate motor carrier, to whose equip-
ment the standards are applicable.

  In the present rulemaklng proceeding,
the Director is concerned primarily with
the following  issues relating  to the en-
forcement regulations now under consid-
eration:  (1)  adequacy of the proposed
rules to ensure that the EPA standards
are fully enforced;  (2) flexibility of the
enforcement procedures specified in the
proposed rules to  ensure that enforce-
ment agencies can make use of a wide
range  of measurement sites; and (3)
technical validity of the proposed rules,
in that they maintain, but do not de-
crease or increase, the stringency of the
EPA standards.
  In developing the  proposed enforce-
ment regulations, the Bureau of Motor
Carrier Safety has given extensive con-
sideration to  the experience gained by
enforcement personnel of the States of
New  York  and California, the  city of
Chicago, and  the New Jersey Turnpike
Authority, which now operate programs
of noise emission regulation and enforce-
ment, as well as the enforcement experi-
ence  of the  Bureau's  own  personnel.
Background studies of noise enforcement
methodology  prepared  for those,  and
other,  government agencies  have been
extensively consulted  during  the prepa-
ration of this proposal. Among the stud-
ies consulted were the following:
Research on Highway  Noise Measurement
  Sites, Ben H  Sharp, Wyle Laboratories, El
  Segundo. CA,  Prepared for California High-
  way Patrol under  Contract No. C-219-71-
  72. March 1972.
Truck  Noise—/, Peak  A-Welghted  Sound
  Levels Due to Truck Tves, National Bureau
  of Standards,  prepared for U.S. Department
  of  Transportation, Report No. OST-ONA-
  71-9, Sept. 1970.
Truck Noise—II, Interior and Exterior, A-
  Welghted Sound Levels of Typical Highway
  Trucks, W. H. Close and R. M. Clarke. IT 8.
  Department of Transportation Report No.
  OST/TST 72-2, July 1972.
Field Measurement Procedures for Noise En-
  forcement. Bolt Beranek and Newman, Inc.,
  Cambridge, MA, submitted to the Corpora-
  tion Counsel, City of Chicago,  Department
  of  Environmental Control, July 1973.
Background Document  for Interstate Motor
  Carrier Noise Emission Regulations, US.
  Environmental Protection Agency,  EPA-
  650/9-74-017, October  1974.
Secomemndations:  Vehicle Noise Emission
  Regulations and Measurement Procedures,
  C  W Dietrich, Bolt Beranek and Newman,
  Inc , Cambridge, MA, Report No. 2782, sub-
  mitted to New Jersey  Turnpike Authority,
  Jan. 1974.

        MEASUREMENT  PROCEDURES

   The measurement procedures the Di-
rector proposes to institute are basically
identical to those now used by  most
agencies that currently enforce  noise
emission regulations. There are, however,
some  notable  differences  from those
standard  practices  in  this  propose!
Among them are the following -
  1. Measurement tolerances. The rules
of the State of Hawaii and the city of
Chicago  currently  specify a  tolerance
level to take into account the inaccuracy
of sound level measurement systems as
currently manufactured.  The  Director
•iocs not now Intend to specify such a tol-
erance factor in  the Bureau's  enforce-
ment regulations, even though the Bu-
reau is aware of the fact that noise en-
forcing agencies routinely  add or sub-
tract  tolerances of l to 2 dB to or from
the observed noise emission levels of mo-
tor vehicles  they monitor before consid-
ering enforcement action. The Director
believes that if a tolerance factor is ap-
plied, It should be  applied through the
mechanism of administrative policy in-
structions  to  enforcement  personnel,
rather than  by a specified tolerance level
written into  the enforcement regulations.
This  is the  case  because the  tolerance
level that Is  appropriate in  one situation
may be entirely inappropriate In others.
Some of the  variants are discussed below.
In addition,  the Director is cognizant of
the fact that, under section 18(c) (1) of
the Noise Control Act of 1972, State and
local governments will have to utilize the
procedures specified in the Federal regu-
lations when they carry out their  own
motor carrier noise  emission regulatory
programs.
  Tolerances are  considered necessary
for a number of reasons, such as limita-
ment instruments and atmospheric con-
tions in the  accuracy of sound measure-
ditions.
  The specification to which sound level
measurement  systems  are   currently
manufactured    (American   National
Standard Specification for Sound Level
Meters, ANSI Sl.4-1971. of the American
National  Standards Institute)  specifies
a tolerance band for meter response. In
the case of Type 1 meters, this tolerance
band Is   ±1  dB(A)  for  A-welghting
throughout the frequency range from 50
to 4,000 Hz.  (At frequencies above or be-
low this range, the tolerance exceeds ± 1
dB.)  In thec ase  of Type 2 meters, this
tolerance band is  ±2  dB for A-weight-
Ing throughout the frequency range from
315 to 630 Hz and from 1,000 to 1,250 Hz.
(Again, at frequencies above or below the
specified  range, the tolerance exceeds ± 2
dB.) What this means is that, In the case
of a Type 2 meter, for example, an ob-
served meter reading may deviate as
much as 2 dB from the actual A-weighted
sound level generated by the noise source,
even  though the meter conforms to the
specifications  of  ANSI Sl.4-1971. It
should be noted, however, that the devia-
tions  referred to  in those specifications
are measured at single, discrete frequen-
cies. The overall frequency response tol-
erance of Type 1 and Type 2 meters to
broad band (multi-frequency)  noise  Is
not specified In ANSI Sl.4-1971. Never-
theless, the  fact that ANSI  Sl.4-1971
permits deviations from the true reading
                               FEDERAL REGISTER, VOL. 40, NO. 41—FRIDAY, FEBRUARY 28, 1975

-------
                                                 PROPOSED  RULES
                                                                        8659
of the magnitude noted above Indicates
that enforcement tolerances are In order.
  Weather conditions at  and near a
measurement site can have an effect on
noise measurements at the site. The pre-
cise magnitude of these effects Is not en-
tirely known at present, but several pub-
lished studies indicate that they exist.1
Because  of the  above-mentioned  vari-
ables and others, the Director has con-
cluded that a tolerance factor to be sub-
tracted from the observed meter reading
would be warranted as a general operat-
ing practice. At the same time, the Direc-
tor also  has  concluded  that no single
tolerance factor can, or should, be speci-
fied in the regulations This is  the case
tscause differences in the circumstances
under which  measurements  are  made
will require application of different tol-
erance factors. For example, the Bureau's
enforcement  staff  will,  In the  initial
phases of the Federal enforcement pro-
gram, be using Type 2 sound level meters.
  They will be conducting measurements
at a large number of sites under varying
weather  conditions. In  these  circum-
stances, It is anticipated that a tolerance
factor of 2 dB would be appropriate. On
the other hand, a municipal government
may be enforcing noise emission regula-
tions using equipment meeting the  ANSI
requirements for Type 1 meters, and it
may  be  using only  a single site, with
sound attenuation characteristic known
to provide repeatable results, in relatively
stable weather conditions. In this type of
case,  a smaller administrative tolerance,
on the order of  1 dB,  could possibly  be
justified.
  For the foregoing reasons, the Bureau
does  not  propose to  establish  enforce-
ment tolerance factors in  the  proposed
rules. The Bureau  will be available  to
work with States and other government
agencies  to establish reasonable  adminis-
trative tolerances for  specific measure-
ment conditions  and  locales.  It  is  the
opinion of the Bureau that motor carriers
and manufacturers of  motor  vehicles.
would be best advised to  apply no toler-
ance factor when testing the noise propa-
gation characteristics of  their equip-
ment or  products.
  2. Open site requirements  The open
site characteristics proposed in the text
of the rules set forth below differ some-
what from those employed by some en-
forcement agencies.  Figure  A,  below,
shows the open site currently utilized by
the California Highway Patrol, the city
of Chicago, and the New Jersey Turnpike
Authority.
  1 Ruteriiig, E O , The Application of Vehicle
Noue Test Results in the Regulatory Process,
In Proceedings- Conference on Motor Vehicle
Noise, General Motors Corp. (1073); Hemdal,
J. P., et al, A Study of the Repeatability at
Motor Vehicle Noise Measurement Situ, En-
vironmental Research Institute of Michigan,
ERIMNo. 301300-1-F (1974).
        f      \  /      \
                            MICROPHONE
                            TMGETFOMT
MICROPHONE
LOCATION
                             CENTO OF
                             MICROPHONE
                             UNE
                FiguraA
  Figure B, below, shows the open site
referred to in the Environmental Protec-
tion Agency's Background Document for
Interstate Motor Carrier Noise Emission
Regulations
MICROPHONE
LOCATION
                 Figure B
  The open site characteristics are spec-
ified with  the intention of eliminating
or minimizing the effects of sound that
is reflected from surfaces that would not
be present in a hypothetical^ "perfect"
measurement site. The contribution that
this reflected sound can make to the ob-
served sound level  reading varies: it is
a function of several variables, including
the acoustical properties of the reflect-
ing surface and the distance between the
surface and  both the vehicle  and the
microphone of the sound level measure-
ment system.
  The Director  is proposing to require
measurements to be made at a site that
has an open area around both the micro-
phone and the vehicle  for a  distance
equivalent to the distance between the
microphone and the vehicle.  This re-
quirement is  a compromise between the
need  for  a test site that is, so far as
practicable, free of reflecting surfaces—
other than the  ground—particularly in
the critical area between the microphone
and the vehicle—and the need to maxi-
mize the  number of sites available for
enforcement of the standards.
  Because the  open  site distances are
equal to the distance between the micro-
phone and the  vehicle, reflected sound
waves will always have to travel a dis-
tance to reach the microphone (and so
be detected by the measurement system)
that is significantly greater than the dis-
tance the primary  sound waves propa-
gated by the vehicle must travel to reach
the microphone. This will result In a sub-
stantial  attenuation of reflected sound
waves, so that the maximum contribu-
tion that reflected sound could make to
an observed sound level reading would be
negligible.
  3. Distance correction factors. The dis-
tance correction factors in § 325 73 of the
proposed rules do not provide for making
measurements at distances  closer than
35 feet from the vehicle or farther than
83 feet  from the vehicle. This is a de-
parture  from  the practice  followed by
California authorities, who permit meas-
urements to be made at distances up 10
118 feet It Is also a departure from the
practice In several jurisdictions of allow-
ing measurements  to be made  in the
range from 25-35 feet.
  There is good reason for  these "aria-
tions. The theory  of measuring sound
emissions is based  on the premise that
sound levels drop 6 dB every tune the
distance between the sound source and
the receiver Is doubled. This premise as-
sumes that there is a single-point source
radiating sound into  free space. In the
real world, this is obviously not the case.
Motor vehicles do not emit noise from  a
single point   The  fact  that tires and
numerous engine and other mech&mcal
components emit noise makes for a com-
plicated sound propagation  source  The
environment into  which this noise   is
emitted  is obviously not free space; in-
deed, in many cases, the environment  is
not  even hemispherical free space be-
cause of variations in terrain at or near
the test site. Accordingly, erratic "near
field" effects may be found  at measure-
ment distances closer than 35 feet, mak-
ing  repeatable measurements at those
distances difficult.  For this  reason, the
proposal would not permit measurements
made at distances closer than  35 feet
from the centerllne of the  path of the
vehicle  to be used for enforcement pur-
poses
  Measurements  made  at distances
greater  than  83 feet from  the  vehicle
also pose open site and ambient sound
level  problems  which  make measure-
ments at such distances impracticable as
a general rule
  Therefore, the Director is proposing  to
restrict  the range  of measurement dis-
tances to not less than  35 feet and not
more than 83 feet from the center of the
path of vehicle travel. These restrictions
arc identical to those employed by the
New  Jersey  Turnpike  Authority, and
their presence does not appear to  have
hampered the Authority's  enforcement
program.
  4. Ground surface  correction factor.'
The proposed  rules take into  account
differences in the acoustical character-
                               FEDEML REGISTER, VOL. 40,  NO. 41—FRIDAY,  FEBRUARY 28,  1975

-------
 f fififl
                                                  HOPOSED  U)US
 IsUcs of different t>pes ol  ground sur-
 faces that may  be  found between the
 tehkle and  the microphone. The En-
 Mroruneutal  Protection Agency. In Issu-
 ing the standards, dearly Intended that
 both  high-speed and low-speed pass-by
 measurements would be made at typical
 roadside sites rather thin m a laboratory
 situation The sites that neie used to ac-
 cumulate the suney data typjcaLly had
 a short grass cover between  the highway
 and the microphone location pD-nt  These
 t>pes ol sites are considered acoustically
 1 soft' sites When pass-by measurements
 are made at sites which hate  asphalt.
 concrete, or  other  acoustically ' hard '
 surface material between the sehicle and
 the microphone, readings  substantially
 higher than tiMee observed at  soft'sites
 are obtained.
  Accordingly,  the Director proposes to
 require subtraction of a 2 cLB correction
 factor from a measurement of noise em-
 niissions  during  highway  operations
 when  the  measurement is  made at  a
 hard '  sue.  Subtraction of  that  figure
 w ill ensure that the'  hard site measure-
 ment produces an observed reading sub-
 stantially equivalent to  the reading that
 would hare been obtained if the meas-
 urement had been made at the "soft'
 site contemplated 1:1 the EPA standards
  Sjmlarly. the Em iroiimenta!  Protec-
 tion Agencv  In  promulgating it* stand-
 ard for noise emissions under stat.onary
 test  clearl*  contemplated  a measure-
 ment to be conducted at an acoustically
 'hard' site  If  a measurement is  made
 at a  'soft site  it would fail to show ac-
 curately whether and  the extent  to
 whicn the vehicle either conforms to the
 standard or fails to conform to it unless
 a correction  factor is added to  the ob-
served sound level  generated  by the
motor vehicle under  stationary test For
 this reason the Director proposes a 2 dB
 correction factor to be added to observed
sound levels generated by motor vehicles
under stauonary test at 'soft sites
  5 Guard rails. The Director is propos-
ing to consider a test site adequate for
noise   emission   measurements  e\en
 though there  are metal guard rails with-
in the. site  The purpose ol this proposal
Is  to  make available for measurement
purposes a large number of sites near
 irAjar highways which  contain no sub-
sia^ual sound-rejecting surfaces  other
 than  guard  rails Numerous potential
sites are adjacent to four-lane  divided
 highways,  having   conunuous   metal
 guard rails separating opposing lanes of
 t.-a£3c The Bureau believes ihat the cor.-
 tnbuuoa.  of  sound  waves  reflected off
 guard  raUs of that  type to  the overall
 observed sound  level at a sue adjacent
 to  such a highway would be negligee
 Ke\ ertheless  the Director does not pro-
 pose  to  allow  guard  rails  within the
 measdremerr. area, tee area  between the
 \ eiLde and the murrophcne
  6  \ifucl  t:re inspection  The  EPA
 s-ar.dard on tires '40 CFR 202 23> makes
 :r.e use o' tires having A tread pattern
 co.-.sist:.::g mainly of cavities or pockets
 i • iolat!on if the tread  of the tire when
 c-finally manufactured  or newly  re-
 manufactured »as  composed  pnmnuh
. of cat ities or pockets
   It is. of coarse, difficult fbr an inspec-
 tor,  looking at a motor vehicle during
 a  roadside  or terminal inspection,  to
 de'ermine whether  the tire tread thnt
 meets his eyes is IdenOcnl to.  or  dif-
 ferent from, the trend that the tire had
 when it was new To achieve the objec-
 tive  of the standard,  the Duector pro-
 poses to place on the motor carrier w hose
 \ehlcle is equipped nitli a  tire haung
 n ' cm its" or • pocket" tread pattern the
 burden  of establishing that the tread
 pattern   was of  a  permissible  variety
 nhen originally manufactured or newly
 remanufactured.
   Another feature of  tne tire standaid
 that creates difficulties for enforcement
 agencies  m  the  "savines" clause which
 absolves a mother earner of liabllitv for
 operating a motor vehicle on a tire hav-
 ing  a prohibited trend pattern If the
 carrier ' demonstrates  it to  be In com-
 pliance VMth the noise emission standard
 specified   for  operations  on  highways
 with speed limits of more than 35 MPH
 u c . the  high-speed pass-b> standard1.
 The  st-anaiid is mute on  the  subject
 of where the demonstration  will be con-
 ducted Tlv Bureau frequently conducts
 inspections of motor  vehicles nt loca-
 tions where a high-speed pass-by  test
 cannot be marie  if g  at carriers' termi-
 nals1 . a::d it does not appear practicable
 to m.ike sound  levei  measurements  in
 conjunction with eveiy usual tire In-
 spectio:-.  For these le.isons  the Director
 proposes  that  the motor carnc  will  be
 given the opportunitv  to  de:  ..nstrate
 tlie  \ehicles conformity to the high-
 speed noise emission standard for high-
 way  operations at a place  and tune  to
 be selected  by the  Burea1:. It may  be
 that pass-by  measurements are being
 made at the  same time and place  as
 visual tire Inspections. In which event
 the demonstration can be performed  at
 that tune and place. But if  the two en-
 forcement activities are not being con-
 ducted jointly  the demonstration  will
 have to be conducted at  another tune
 fcnd place
   The Bureau has  not found it neces-
 sary to make any provision  In the pro-
 posed rules  for  measurement of noise
 emissions of motor vehicles operating  at
 a speed of 65 miles per hour on highways
 hanng unlimited  speed limits  By vtrtue
 of the enactment and Implementation
 of section 2 of the Emergency Highway
 Energy Conservation Act, Pub L  9&-239
 and  23 U S.C. 154 there is  no highway
 without   a posted  speed  limit  in  the
 United States and the highest posted
 speed limit U 55 miles per hoar
   7  Vehicles equipped with fan clutches
 The  proposed procedures would permit;
 a vehicle equipped with a fan clutch  to
 undergo  the test for  compliance  with
 the stariArd  for operation under sta-
 tionary teat while the fan clatch is dis-
 engaged  Experience with fan  dutches
 Indicates that they  produce salutory re-
 sults in the contest of  truck noise abate-
 ment and that   according!},  their ir.-
 staliatlon should  be encouraged In the
interest of carrying out the purpose of
tbeNoice Control Acl
  M part ol One '-quiet truck program"
sponsored by the Department of Traas-
pertaU0n. International Harvester Com-
pany,  a  truck manufacturer,  equipped
the radiator fan drives of 24 heavy duty
trucks with either "on-off" or  modulAt-
ig-type fin clutches These devices »ere
designed either to disengage the fan from.
its pulley drive completely  or to reduce
the radiator fan's rotational speed below
that of the engine during periods  of re-
duced engine cooling thermal load. It be-
came apparent that installation of fan
clutches  produced  a   twofold  benefit.
First  viith. the fan either totally stopped
or operating  at a  reduced rpm  rate.
radiator  fan  noise  Is significantly re-
duced  Reductions in fan-generated noise
on the order of 20 dBiAJ  are tipical
nher.  these  t>pes of  devices  ore in-
stalled • Second, the instillation of a fan
dutch lesults  m a reduction or elimina-
tion of tile e:;gi:ie hoisepower thnt would
otherwise be  required  to  operate the
rariiatci  fan at times  when Its engine-
cooling capability Is not needed As a re-
sult.  the  vehicle achieves n 5- to 10-per-
cent  saving in fuel consumption.'
  Field tests of the 24 vehicles-, involving
more than 30 000 hours of vehicle opera-
tion  ar.d nenrlv 1 100000 vehicle  miles,
mdicr.ted that the  average fan-on time
for vehicles equipped with an on-ofT type
of fan clutch is slightly under 3 percent
Significant fan-on time * was less than I
percent for vehicles equipped with this
type of  fan  clutch  Significant fan-on
time for vehicles equipped with modu-
lated far.-dnve clutch units was also less
than 1 percent of total engine operating
time,  even  during the  warm summer
months
  It Is apparent therefore, that Installa-
tion  of radjator fan-drive  clutches re-
sults in significant noise abatment bene-
fits as weil as other benefits. The  noise
reduction  associated with  installation
of fan clutches occurs between 97 and 99
percent of the time the vehicle ts operat-
ing In light of these benefits, the Direc-
tor  has concluded  that  widespread in-
stallation of fan clutches should be en-
couiaged He proposes, therefore,  to re-
quire  the stationary test of a vehicle
equipped with  a  fan clutch to be per-
formed with the. clutch disengaged.
  The Bureau  at  this time  anticipates
that it will conduct a program, of enforc-
ing the noise emission standards through
the same techniques that are used to en-
  : Dan^.e-.ala  R  J ev al.  .Voue  Control
ffaidboo':   'or  Di-:;el   Pouertd   Vehicles.
U S D O T  B«por'.  No.  DOT-TSC-QST-74-5
US74).
  : U SJD O T um U.5.E FA. Study o} Poten-
tial far  Motor Vehicle  Fuel  Economy  1m-
praie^ieni,  Truct  and  Bus  Panel Report
(19751
  •  S:g:ii5car; .'aji-on time ' was defined as
-.-.e  period of -.!:-_e during »hlch the  fan
operated &• a speed of  1,600  rpm  or more
This -pin :eiel was se'ected because  at l 600
rp-n  fa-  nolfe wcjld be approximately 10
dB A i te.c"  i's r.a^ltr.bm  level
                               HOHAl IKimi VOL 40, NO 41-
                                                                   r. FEUVAIY ja,  ?»7i

-------
                                                 PROPOSED RULES
                                                                         8661
force the Federal Motor Carrier Safety
Regulations Inspection and surveillance
of motor  carriers  will be  carried  out
through terminal surveys and equipment
inspection  and  driver-equipment com-
pliance checks at roadside sites. Under
the Noise Control Act, a violation of an
EPA motor carrier noise emission stand-
ard gives  rise to the possibility  of  im-
posing sanctions under section 11 of the
Act. The sanctions include criminal pros-
ecution of  knowing or willful violators,
in which the maximum sentence is a fine
of $25,000 per day, imprisonment for 1
year, or both, in the case of first offend-
ers, and a flne of $50,000  per day,  im-
prisonment for 2 years, or both. In the
case of subsequent offenders. In addi-
tion,  section 11 authorises the  United
States to  secure an Injunction against
future  violations   in  the  appropriate
United States District  Court and per-
mits the Administrator of  the Environ-
mental Protection Agency,  after notice
and the opportunity for hearing, to issue
cease-and-deslst orders against violators.
  Section 18(b) of the Act authorizes the
Secretary of Transportation to carry out
the regulations for  ensuring compliance
with  EPA  noise  emission  standards
"through the use of his powers and du-
ties of enforcement and inspection au-
thorized by the Interstate Commerce Act
and the Department  of Transportation
Act" The basic "powers and duties" re-
ferred to  hi section  18(b)  are derived
from section 220 of the Interstate Com-
merce Act, 49 U S.C. 320. Section 220 re-
quires motor  carriers to  submit their
properties and documents for Inspection
and examination by designated special
agents of  the  Department  of Transpor-
tation's Federal Highway  Administra-
tion. This is the statutory basis for sec-
tion 325.13 of the proposed .rules. Section
220 also authorizes the Department of
Transportation to require  periodic  and
special reports from motor carriers sub-
ject to the Department's jurisdiction. It
Is on this basis that the Bureau now re-
quires motor carriers whose equipment is
found to be defective during a  driver-
equipment compliance check to make a
report to the Bureau certifying  that re-
pairs have been made. See 49 CFR 396 5.
The Bureau Is  considering adopting a
similar procedure in the case of motor
vehicles which are found to be In viola-
tion of the noise emission standards.
  The use by the Bureau of the enforce-
ment techniques described above does not
limit  or restrict the enforcement tech-
niques or sanctions that a State or politi-
cal subdivision thereof may employ In
carrying out  its  motor  carrier noise
emission regulatory program, even after
the effective date of the EPA standards
and the Department of Transportation's
regulations  for  Implementing  those
standards.  Section  18 (c) of  the Noise
Control Act provides that, after the Fed-
eral regulations have  become effective.
a State or Its political subdivisions may
not  adopt  or enforce  noise  emission
standards applicable  to motor  carriers
subject to the Federal standards unless
(1) the State or local standard is iden-
tical to the Federal standard; or (2)  a
special variance for a differing standard
is granted by the Administrator of EPA
after consultation with the Secretary of
Transportation. It is the position of the
Bureau that,   while  the "preemption"
provisions of section 18(c) require States
and ttwlr political subdivisions that have
not secured a special variance to apply
the identical criteria and measurement
methodologies as are specified in Federal
regulations to determine whether a motor
vehicle is in conformity with  noise emis •
slon standards, once a violation is de-
tected, the State or local government may
proceed to Impose sanctions or take other
corrective action in accordance with its
own la1.  Thus, for  example,  a State
could, it it wishes, bring a civil penalty
proceeding against a violator,  notwith-
standing the  fact that, under Federal
law, the violation Is a crime. Similarly,
a State could, if its law permits, impound
equipment found In violation of the noise
emission standards, even though Federal
law  does not  provide for impoundment
as a sanction.
  The rules under consideration at this
time do not explicitly refer to  the matters
discussed here under the heading of "En-
forcement." This is the case because the
resolution of issues relating  to the im-
position of sanctions after violations of
the noise emission standards are detected
Is  a function of statutory construction
rather than regulatory Issuance. The dis-
cussion is included at this point in order
to give interested persons insight Jnto
the Bureau's current thinking on these
important issues.
  In consideration of the foregoing, the
Director of the Bureau of Motor Carrier
Safety proposes to amend Subchapter A
of Chapter m in title 49. OFR, by adding
a  new  part 325,  reading as set forth
below.
  Interested persons are Invited to sub-
mit  written data, views, or arguments
pertaining to  the proposed amendment.
All comments submitted should refer to
the  docket number and notice number
that appear at the top of this document.
Comments should foe submitted In tripli-
cate to the Director,  Bureau of Motor
Carrier  Safety, US.  Department  of
Transportation, Washington, D C. 20590.
All comments  received before  the close
of business on May 1, 1975 will be con-
sidered before further action Is taken on
the proposal. All comments received will
be available for examination  in the pub-
lic Docket Room of the Bureau of Motor
Carrier Safety, Room 3401, 400 Seventh
Street, SW., Washington. D.C. both be-
fore • and  after the  closing  date for
comments.
  This notice of proposed rule making Is
Issued under the authority of section 18
of the  Noise  Control Act of  1972, 42
U.SC. 4917, the delegation of authority
by the Secretary of Transportation at 49
CFR 1.48 (p), and the delegation of au-
thority by the Federal Highway Admin-
istrator at paragraph 7, Chapter 7, Part
I of FHWA Order 1-1.
  Issued on February 20,1975
                ROBERT A KAYE,
                Director, Bureau of
                Motor Carrier Safety.
PART 325—COMPLIANCE WITH  INTER-
  STATE MOTOR CARRIER NOISE EMIS-
  SION STANDARDS
       Subpart A—GwMril Provision*
Sec.
325 1   Scope of the rules In this Part.
326 8   Effective date.
328.5   Definitions
     Subpart B—Administrative Provision*
32611  Isuance,  amendment, and  revoca-
        tion of the rules In this Part.
325 13  Inspection and examination of motor
        vehicles

        Subpart C—Instrumentation
325.21  Scope of the rules In this subpart
325 23  Types of measurement systems which
        may be used.
325 25  Calibration of measurement systems.
326 27  Use of a  windscreen.

  Subpart D—Measurement of Noise Emissions:
            Highway Operations
32531  Scope of the rules In this subpart.
32533  Site characteristics,  highway opera-
        tions.        *
32635  Ambient conditions; highway opera-
        tions.
325 37  Location and operation of sound level
        measurement  systems;  highway
        operations
325 39  Measurement  procedures;  highway
        operations.
  Subpart E—Measurement of Nohw Emissions;
             Stationary Test
325 51  Scope of the rules In thla aubport
325 53  Site characteristics, stationary test
32565  Ambient conditions; stationary test.
325 57  Location  and  operation  of sound
        level  measurement  systems;  sta-
        tionary test
326 SO  Measurement procedure;  stationary
        teat.

       Subpart F—Correction Factors
326 71  Scope of the rules In this subpart.
32573  Microphone distance correction  fac-
        tors.
826 76  Ground surface correction factors
S25.77  Computation of open site require-
        ments—nonstaadard site*.
32570  Application of correction factors.
    Subpart G—Exhaust Systems and Tires
325 91  Exhaust systems.
826 93  Tires.

  AUTHORITY: The provisions of this Part
825 Issued  under sec. 18, 86 Stat. 1234. 1249-
1250. 42 TJ.SC. 4917.

      Subpart A—General Provisions

§ 325; 1  Scope of the rules in this Part.

   (a)  The  rules In  this Part prescribe
procedures  for the  inspection, surveil-
lance, and measurement of motor vehi-
cles and motor vehicle equipment oper-
ated  by  motor  carriers to  determine
whether those  vehicles and that  equip-
ment conform to the Interstate  Motor
Carrier Noise Emission Standards of the
Environmental  Protection  Agency,  40
CFR Part 202.
  (b) Except as provided in paragraph
(c) of this section, the rules in this Part
apply to each motor vehicle operated by
an interstate motor carrier,  regardless of
whether the motor vehicle Is used in in-
terstate or foreign  commerce by  the
motor carrier.
  (c) The rules in this Part do not apply
to—
  (.li A motor vehicle that has a Gross
                               FEDERAL REGISTER, VOL. 40, NO. 41—FRIDAY, FEBRUARY 28, 1975

-------
 8662
           PROPOSED RULES
 Vehicle Weight Rating of 10,000 pounds
 (4,536 kg.) or less;
   (2)  A combination  of motor vehicles
 that has a Gross  Combination  Weight
 Rating of 10,000 pounds (4.536  kg.) or
 less;
   (3) The sound generated by a warning
 device, such as a horn or siren, installed
 in a motor vehicle;
   (4) An emergency motor vehicle, such
 as a flre engine, an ambulance, a police
 van, or a rescue van, when it is respond-
 ing to an emergency call;
   (5) A snow plow in operation, or
   (6) The sound generated by auxiliary
 equipment  which is normally operated
 only when the motor vehicle on which it
 Is installed is stopped or is operating at a
 speed of 5 miles per hour (8 kph) or less.
 Examples of that type of auxiliary equip-
 ment  include, but are not  limited  to,
 cranes, asphalt spreaders, ditch diggers.
 liquid or slurry pumps, auxiliary air com-
 pressors, welders*and trash compactors

 § 325.3  Effective dale.

  The rules in this Part are effective on
 October 15. 1975.

 § 325.5  Definitions.
   (A) Statutory definitions. All terms de-
 fined in  the Noise  Control  Act of 1972
 (Pub. L.  92-574, 86 Slat. 1234) arc used
 as they are defined in that Act.
  (b) Definitions in standards. All terms
 defined in  9202.10 of the  Interstate
 Motor Carrier Noise Emission Standards,
 40 CFR 202.10, are used as they are de-
 fined in that section.

   Subpart B—Administrative Provisions

 § 325.11   Issuance, amendment, and rev-
     ocation of the rules in this Part.

  The procedures specified in Part 389 of
 this Chapter  for the  issuance,  amend-
 ment, or revocation of the Federal Motor
 Carrier Safety Regulations apply to rule-
 making proceedings for  the Issuance,
 amendment, or revocation of the rules in
 this  Part.

 § 325.13   Inspection and examination of
     motor vehicles.

  (a) Any special agent of  the  Federal
 Highway Administration (designated In
 Appendix B to Subchapter B  of this
 Chapter)  is authorized to Inspect, ex-
amine, and test a motor vehicle operated
by a motor earner in accordance with
 the procedures specified in this Part for
the purpose of ascertaining whether the
motor vehicle and equipment installed on
the motor vehicle conform to the Inter-
state Motor  Carrier   Noise  Emission
Standards of the Environmental Protec-
tion Agency, 40 CFR Part 202.
  (b) A motor carrier, its officers, driv-
ers, agents, and employees must, at any
time, submit a motor vehicle used in Its
operations  for Inspection, examination,
and testing for the purpose of ascertain-
ing whether the motor vehicle and equip-
ment Installed on It conform to the In-
 terstate Motor Carrier Noise Emission
 standards of the Environmental Protec-
 tion Agency, 40 CFR Part 202.
        Subpart C—Instrumentation
 § 325.21  Scope of the rules in this sub-
      part.
   Ti.w rules in this subpart specify cri-
 teria for sound  level measurement sys-
 tems which are  used to make the sound
 level measurements specified In Subpart
 D and Subpart E of this Part.
 § 325.23  Types of measurement systems
      which may be used.
   The sound level measurement system
 must meet or exceed the requirements of
 American National Standard Speciftca-
, tion for Sound Level Meters (ANSI 81.4-
 1971), approved  April 27, 1971, Issued by
 the American National Standards Insti-
 tute,1 throughout the frequency range of
 50 to 10,000 Hz for either—
   (a)  A Type 1 sound level meter;
   (b)  A Type 2 sound level meter; o<
   (c) A Type S sound level meter which
 has—
   (1) A-weighting frequency response;
   (2) Fast dynamic characteristics of its
 Indicating instrument; and
   (3) Relative response level tolerances
 consistent with those of either* a Type 1
 or Type 2 sound level meter, as specified
 In section 3 2 of ANSI Sl.4-1971.
 § 325.25  Calibration  of   measurement
      systcmo.
   (a) The sound level measurement sys-
 tem  must be calibrated at one or  more
 frequencies in the range from 250 to 1,000
 Hz at  the beginning and  at the :nd of
 each series of measurements. Th. sound
 level measurement system must also be
 calibrated at one or more of those fre-
 quencies immedlat:.y after measurement
 of a violation of a Standard in 40 CFR
 202 20 or 40 CFR 202.21.
   (b) The  calibra,or used to calibrate
 the  sound level measurement system in
 accordance with paragraph (a)  of this
 section must produce a sound pressure
 level at the microphone that Is known to
 be accurate  within a tolerance of  ±1.0
 dB of the sound  pressure level of a pre-
 scribed source. The calibrator must have
 been checked within  the preceding year
 by its manufacturer,  a representative of
 Its manufacturer, or a person, of equiva-
 lent special competence to verify that its
 output meets the manufacturer's design
 criteria.

 § 325.27  Use of a windscreen.
   A windscreen shall be Installed on the
 microphone of the sound level measure-
 ment system. Installation  of the wind-
 screen shall  not cause a change in the
 sensitivity of the system of more  than
 ±0.5 dB in the frequency  range from 0
 to 5  kHz or more than ±2.0 dB In the
 frequency range  from 5 kHz to 8 kHz.
    Subpart D—Measurement of Noise
      Emissions; Highway Operations
 § 325.31   Scope of the rules in this  sub-
     part-
  The rules In this subpart specify con-
 ditions and procedures for measurement
 of the sound level generated by a motor
 vehicle engaged In a highway operation
 for the purpose of ascertaining whether
 the   motor  vehicle  conforms  to  the
 Standards for Highway Operations set
 forth In 40 CFR 202.20.
 § 325.33   Site characteristics; highway
     operations.
   (a) Measurements shall be made  at a
 test site which Is adjacent to, and in-
 cludes a portion of. a travelled lane  of a
 public  highway. A microphone  target
 point shall be established on the  center-
 line of the travelled lane of the highway,
 and a microphone location point shall be
 established on the ground surface not
 less than 35 feet (10.7 m.) or more than
 83 feet (25.3 m.)  from the microphone
 target point and on  a line that is  per-
 pendicular  to the   center-line  of  the
 travelled lane of the highway and  that
 passes  through the  microphone  target
 point. In the case of a standard test  site.
 the microphone location point is 50  feet
 (15.2  m.)   from the  microphone  target
 point. Within the test site is a triangular
 measurement area. A plan view diagram
 of a standard test site, having an open
 site within a 50-foot (15.2 m.) radius of
 both  the  microphone target  point  and
 the microphone location point, is shown
 in Figure  1. Measurements may be made
 at a test site having smaller  or greater
 dimensions in accordance with the rules
 In subpart F of this Part.
                             MICROPHONE
                             TARGET POINT
                            CENTERLINEOF
                            THE TRAVELLED
                            LANE OF
                            THE HIGHWAY
  1 Copies of the specification may be secured
 from American National Standards Institute,
 1430 Broadway, New York, New York 10018
MEASUREMENT
AREA
 MICROPHONE
 LOCATION POINT
                figure 1
            STANDARD TEST SITE;
            HIGHWAY OPERATIONS

  (b) The test site must be an open site,
essentially free of large sound-reflecting
objects. The following objects may be
within the test site if they are outside
of the triangular measurement area of
the site:
  (1) Fire hydrants.
  (2) Telephone and other utility poles.
  (3) Rural mailboxes.
                              FEDERAL REGISTER, VOL 40, NO. 41—FRIDAY, FEBRUARY 28, 1975

-------
                                                 PKOfOSED  RULES
                                                                        8*363
  (4) Guardrails of any type of con-
struction except solid concrete barriers.
  (5) Any vertical surface (such as a
billboard), regardless of size, having a
lower edge more than 15 feet (4.6 m)
higher than the surface of the traveled
lane of the highway.
  (6)  Any  uniformly smooth  sloping
surface slanting away from the highway
(such as a rise in grade alongside the
highway)  with a slope that is less than
45 degrees above the horizontal.
  (7) Any surface slanting away from
the highway  that is  45 degrees or more
and  not more than 90 degrees above the
horizontal, if all points on the surface
are more than 15 feet (4.6 m ) above the
sui face of  the  traveled lane  of the
highway.
  (c)  One  or  more  curbs  having  a
vertical height of 1 foot (3 m.) or less
may be within the test site (including the
triangular  measurement  area  of the
site)  However, the test site must be free
of any cu u  with a  vertical height ex-
ceeding 1 foot (.3m).
  fd) The surface of the  ground within
the  measurement area must be  flat  to
within +2 feet (+.6 m.)  and —6 feet
(-18m) of a horizontal plane passing
through the  centerhne of the travelled
lane of the highway Except for the high-
way and its adjacent shoulder, the sur-
face of the ground within the measure-
ment area of a standard test site must
be predominantly covered with grass  or
other ground cover. However, If the sur-
face of the ground within the measure-
ment area (exclusive of the highway and
its adjacent shoulder)  is predominantly
covered with concrete, asphalt, packed
dirt, gravel,  snow, or similar reflective
material, the correction factor specified
in § 325.75 applies to the measurement.
  (e) The travelled lane  of the highway
within the test site must be dry, paved
with relatively smooth  concrete or as-
phalt, and free of—
  (1) Holes or other defects which would
cause a motor  vehicle to  emit Irregular
tire  noises or  body.or  chassis Impact
noises; and
  (2) Loose material, such as gravel  or
sand.
  (f) The travelled lane  of the highway
on which the microphone target point Is
situated must not pass through a tun-
nel or underpass located within  100 feet
(30 5 m.)  of that point.

§ 325.35  Ambient  conditions; highway
     operations.
  (a)  Sound. The ambient A-welghted
sound level at the microphone location
point, measured with fast meter response
using a sound level measurement system
that conforms to the rules in { 325.23,
must not exceed the level specified  In
Table 1 or Table 2 set forth below.
                                       TABLB 1 -Unmrtmaitt Mali at "OUT TW Site u
If Uu distant*
 between the
 micropimM
 location point
 and Uiemlcio-
 phone target
 point Is—
Th> minimum
 amMcnt
 •rand level
 for tests M
 highway:
 with a posted
 speed limit of
 85 mph (58 3
 kph) or less
 Is—
The maximum
 ambient sound
 level lor test]
 at highways
 with* period
 spc-jd Hralt ol
 more than 85
 mph (56 3
 kph) is—
35 foci (10 7m) or
more but less
than 39 (eel (11 9
m) 	
39 feet (11 9m) or
more but less
than U feet (131
m) 	 	
43 fret (181m) or
more but lesi
than 48 feet
(14 (1m) 	
48 feet (146m) or
more hut less
than 58 feet
(171 m) 	
58 feel (17 1 m ) or
more but loss
thnn 70 feet
(218m) 	
70 fret (21 3 in ) or
more but less
than 83 feet
(2S3m) 	



79dB(A)



78 dn (A)



77dB(A)



78dB(A)



76 dB(A)



74  	 	
SB feet (17 1m.) or
more but less
than 70 foet
tZlJim)
70 feel (21 3 m ) or
more but less
than 83 feet
(253 m)

The minimum
ambient
sound level
for tests at
highways
with n posted
speed limit of
85 mph (M 3
kph) or less
k—
81 dB(A)
80 dB(A)
70 dD(A)
78dB(A)
77 dB(A)
70dB(A)

The maximum
ambient sound
levrl for tcsls
at highways
with a posted
speed limit of
moiethanSi
mph (M 3
kph)ls-
85dTI(A)
84dB(A)
S3dB(A)
82dB(A)
81 dB(A)
80 dB(A)

  (b)  Wind.  The  average  continuous
wind velocity and the goat wind velocity
must not exceed 12 miles per hour (19.3
kph) at the microphone of the sound
level measurement  system.
  (c) Precipitation. Measurements must
not be made while It Is raining or snowing
at the  test site.
§ 325.37  Location   and  operation  oC
     sound  level  ateasurcment system;
     •Jghwar operations.
  (a) The microphone of a sound level
measurement  system that conforms to
the rifle* in « 325.23 shall be located as
foDowE:
  (1) If the microphone location point is
at or below a horizontal plane that In-
tersects the microphone target point, the
microphone shall be positioned above the
microphone location point so that it Is
not less than 3& feet (1.1 m) and not
more than 4'/2  feet (1 4 m.)  above that
horizontal  plane.
  (2) If the microphone location point
is above  a horizontal plane that inter-
sects  the  microphone  target point, the
microphone shall  be  positioned above
the microphone location  point so  that
it is at least 3'/2 feet (11 m.) above that
point, not  more than  4'/2 feet (1.4 m)
above that point, and not more than 6
feet (18m) above that horizontal plane.
  (b) When the sound level measure-
ment system is hand  held or  is other-
wise monitored by  a person located near
its  microphone, the holder or monitor
must orient himself so that  his torso—
  (1) Is at least 2 feet (6m)  from the
system's microphone;
  (2) Is facing in a direction parallel to
the centerline  of  the  travelled lane  of
the highway; and
  (3) Is not located between the micro-
phone location point and the microphone
target point.
  (c) The microphone of the sound level
measurement system shall be oriented to-
ward the traveled lane of the highway
at the microphone target point at  an
angle that is consistent with the recom-
mendation of  the system's  manufac-
turer. If the manufacturer of the system
does not recommend an angle  of orien-
tation for its  microphone,  the  micro-
phone shall be oriented toward the high-
way at an angle of not less than 70 de-
grees and  not  more than perpendicular
to the horizontal  plane of the traveled
lane of the highway at the microphone
target point.
  (d) The sound level measurement sys-
tem shall be set to the A-weighting net-
work and "fast" meter response mode.

§ 325.39   Measurement fvoredare; high-
     way operations.
  (a) In accordance  with the rules  in
this subpart, a measurement  shall  be
made of the sound level generated by a
motor vehicle  operating  through the
measurement area on  the traveled lane
of the highway within the test site, re-
girdless of the  highway grade,  load, ac-
celeration or deceleration.
  (b) The sound level generated by the
motor vehicle is the highest reading ob-
served on the sound level measurement
system as the vehicle passes through the
measurement area, corrected, when ap-
propriate, in accordance with the rules
in subpart F of this Part. However, the
sound level reading is valid only if the
observed sound  level of the vehicle be-
ing measured, before application of any
correction  factor, is observed to rise  at
                               FEDERAL REGISTER, VOL 40, NO. 41—TODAY, FEBRUARY 28. 1975

-------
8664

least  6  dB(A)   before  the  maximum
sound level occurs and to fall at least 6
dB(A)  after the maximum sound level
occurs.
  NOTE—The  Standards for Highway  Op-
erations specify a maximum permissible cor-
rected sound level reading of 86 db(A) on
highways  with speed limits of 35 MPH or
less and DO dB(A) on highways with speed
limits of more than 35 MPH when measured
at a standard test site at  a distance of BO
feet See 40 CFB 202 20

    Subpart E—Measurement of Noise
       Emissions; Stationary Test

§ 325.51   Scope of llir rule* in lliis suh-
                                                  PROPOSED RULES
                           MICROPHONE
                           TARGET POINT
   (a)  The rules in this subpart specify
 conditions and procedures for measuring
 the sound level generated by a motor ve-
 hicle when the vehicle's engine is acceler-
 ated from idle with wide open throttle
 to governed speed  with the  vehicle sta-
 tionary, its transmission in neutral, and
 its clutch engaged,  for the purpose 01 as-
 certaining whether  the  motor  vehicle
 conforms to the Standard for Operation
 Under Stationary Test. 40 CFR 202 21.
   (b)  The rules in this  subpart apply
 only to a motor vehicle that is equipped
 with an engine speed governor.

 § 325.53   Site cliuruclcristics; stationary
     tost.
   (a)  The motor  vehicle to be  tested
 shall be parked on the test site. A micro-
 phone  target  point shall  be established
 on the ground surface of  the site on the
 centerline of the lane in which the motor
 vehicle is parked at the  point  on that
 centerline which  Is Intersected  by  a
 transverse plane passing through  the
 front face of the vehicle's front bumper.
 A  microphone location  point shall be
established on the  ground surface not
 less than  35 feet  (10 7 m.) and not more
 than 83 feet  (25 3  m.) from the micro-
phone  target  point  on the ground sur-
 face not  less than 35 feet  (10.7  m.)
centerline of the lane in  which the ve-
hicle is parked and that passes through
 the microphone target point. In the case
of a standard test  site, the microphone
location point Is  50 feet (15.2 m) from
 the microphone target point. Within the
 test  site  is a triangular measurement
 area. A plan view diagram of a standard
test site,  having  an open site within  a
 50-foot (15.2  m.)  radius of both  the
 microphone target  point and the micro-
phone  location point. Is shown In Fig-
ure 2.  Measurements may be made at a
test site having  smaller or  greater di-
 mensions  in  accordance with the rules
 In subpart F of this Part.
                                                                                must not exceed the  level specified ii
                                                                                Table 3 set forth below.
     MICROPHONE
     IOCATIDN POINT
                  Figult 2
              STANDARD TEST SITE
               STATIONARY TEST

   (b)  The test site must be an open site.
 essentially free of large sound-reflecting
 objecU  The  following objects may be
 within the test site if they are outside
 the triangular measurement area of the
 site-
   (1)  Fire hydrants.
   (2)  Telephone and other utility poles.
   (3)  Rural mailboxes.
   (4)  Guard  rails of any type of con-
 struction except  solid- concrete barriers.
   (5)  Any vertical surface, regardless of
 size (such as a billboard), having a lower
 edge more than  15 feet (4.6 m.) above
 the ground.
   (6)  Any  uniformly smooth  surface
 slanting away from the vehicle with a
 slope that is less than 45 degrees above
 the horizontal
   (7)  Any surface slanting away  from
 the vehicle that is 45 degrees or more
 and not more than 90 degrees above the
 horizontal, if  all points  on the  surface
 are more than 15 feet (4.6 m.) ut-ove the
 surface of the ground in  the test site.
   (c) One or more curbs having a height
 of 1 foot  (3m) or less may be within
 the test site  (including  the triangular
 measurement  area of the  site). How-
 ever, the  test site must  be free of any
 curb with a vertical height exceeding 1
 foot (3m).
   (d)(l)  Except as provided  in para-
 graph  (d) (2) of this section, the surface
 of the ground within the measurement
 area must be—
   (1)  Flat and level to within +2 feet
 (+6 m.) and  —6 feet (—1.8 m.) of the
 ground surface at the microphone target
 point;
   (ii)  Predominantly paved with rela-
 tively smooth concrete or asphalt or pre-
 dominantly covered with packed dirt or
 gravel; and
   (iii)  Free of snow.
   (2) If the surface of the ground within
 the measurement area is predominantly
covered with grass or other vegetation,
 the correction factor specified in § 325 75
 applies to the measurement.
 § 325.55  Ambient conditions; stationary
    test.
  (a)  Sound.  The ambient A-welghted
sound  level at the microphone location
point, measured with fast meter response
using a sound  level measurement system
that conforms to the rules in § 325.23
                                        TADLE 3 —Ambient Sound iMtli, Maturcmiiilt I 'udrt
                                                      Stationary Tat
II the dislanca he- The maximum Thmnniiinuni
twecn the micro- ambient sound ambient sound
phone location level Tor testa level for tosls
point anil the at a "hard" at a "soft" site
microphone tor- slleassprcl- assprcilu-ilin
goliiatnlis— ncdln§3J5- 5 3JS 75(1)) Is—
83(d) Is-
35 feel (10 7 m ) or
mure hut Irss
than 3'i for UM 9
m) .. 81 dD(A)
3'Jfi'ct (11 dm )or
mom 1ml loss
tli.m 43 fret (13 1
m) 	 SOdH(A)
43(n(U6m )or
mnrf hut loss
limn M foct (17 1
in) 	 7BdFi(A)
S8feut(17 :m)nr
more hut Joy.
lhnn7Cfoct(Jl 3
m) 	 77<1B(A)
70[<-i>tll!l 3 m) or
more but Irss
limn S3 Icct (2fi 3
m) 	 70dB(A)

TM.IIliA)
78dH(A)
77dl»(A)
7GdB(A)
7Sdli(A)
74dn(A)
                                                                                  (b)  Wind.  The  average  continuous
                                                                               wind velocity and the gust wind velocity
                                                                               must not exceed 12 miles per hour (193
                                                                               kph) at  the microphone of  the  sound
                                                                               level measurement system.
                                                                                  (c) Precipitation. Measurements must
                                                                               not be made while it is raining or  snow-
                                                                               ing at the test site.
                                                                               § 325.57  Ixicntion  and  operation  of
                                                                                    sound  lc\cl measurement  ^slnn;
                                                                                    sUilitmary lest.
                                                                                  (a) The microphone of a sound level
                                                                               measurement system that conforms to
                                                                               the rules in  § 325 23 shall be  positioned
                                                                               not less  than 3'/2 feet (1.1 m) and not
                                                                               more than 4'/2 feet (1.4 m.)  above the
                                                                               microphone location point.
                                                                                  (b) When the sound  level measure-
                                                                               ment system is hand held or is monitored
                                                                               by a pet son located near its microphone,
                                                                               the holder or monitor must orient him-
                                                                               self n-o that his torso—
                                                                                  (1) is at least 2 feet (6m.) from the
                                                                               system's microphone;
                                                                                  (2) Is facing in  a direction  parallel
                                                                               to the longitudinal centerline of the mo-
                                                                               tor vehicle; and
                                                                                 (3) Is not located between the micro-
                                                                               phone location point and the microphone
                                                                               target point
                                                                                 (c) The microphone of the sound level
                                                                               measurement system shall be oriented to-
                                                                               ward the vehicle at an angle that is con-
                                                                               sistent with the recommendation of the
                                                                               system's  manufacturer. If the manufac-
                                                                               turer of the system does not recommend
                                                                               an. angle or orientation for Its micro-
                                                                               phone, the microphone shall be oriented
                                                                               at an angle of not less than 70  degrees
                                                                               and not more than perpendicular to the
                                                                               horizontal plan  of the test site at the
                                                                               microphone target point.
                              FEDERAL REGISTER, VOL 40, NO. 41—FRIDAY, FEBRUARY 28,  1975

-------
                                                 PROPOSED RULES
                                                                         866T>
    Repeat  the procedures specified In
paragraphs (d)  and  (e) of this section
until two  maximum sound level  read-
ings within 2  dB(A) of each other are
recorded.  Numerically average  those
two  maximum  sound level   readings.
When appropriate,  correct the average
figure in accordance with the rules in
subpart F of this Part.
  (g>  The average figure, corrected as
appropriate,   obtained  In  accordance
with paragraph  (f) of this section, is the
sound level generated by the motor vehi-
cle  for  the  purpose  of determining
whether it conforms to the Standard for
Operation Under  Stationary  Test,  40
CFR20221.
  Nor* —The Standard for Operation Under
Stationary Teat specifies  a  maximum cor-
rected sound level reading of 88 dB(A) when
measured at a  standard test Bite at a dla-
t»no»of60feet  See40CFH20211.
      Subpart F—Correction Factors
§ 325.71  Scope of the rules in this sub-
    part.
  (a) The rules In this subpart specify
correction factors which are added to, or
subtracted from,  the reading of  the
sound level generated by  a motor vehi-
cle, as displayed on a sound level meas-
urement system, during measurement of
the motor vehicle's sound level emissions
at a test site which Is not a standard site.
  (b) The purpose  of adding or  sub-
tracting a correction factor Is to equate
the sound level reading  actually gen-
erated by the motor vehicle to the sound
level reading it would have generated if
the measurement  had been made  at a
standard test site.
§ 325.73  Microphone diMuncc correction
    factors.
  If the  distance between the micro-
phone location point and the microphone
target point is other than 50  feet (15.2
m), the maximum observed sound level
reading generated by the motor vehicle
in accordance with B 325.39 of this  Part
or the numerical average of the recorded
maximum observed sound level readings
generated by the  motor vehicle  in ac-
cordance  with 6 325 59 shall be corrected
as specified in the following table:
  TABLE 4—DISTANCE CORRECTION FACTORS
If the distance between
    the microphone lo-  The value (dB(A))
    cation point and  to  be applied to
    the   microphone  the observed sound
    target point Is:      level reading is—
  35 feet  ^101 m)  or
    more but less than
    39 feet (11.9 m)	        -3
  39 feet  (119 in)  or
    more but less than
    43 feet (13 1 m)	        -a
  43 feet  (13 1 m)  or
    more but less than
    48 feet (14 6 m)	        — i
  48 feet  (140 HI)  or
    more but less than
    58 feet (171 m)	         0
  5B feet  (IT 1 m)  or
    more but less than
    70 feet (21 3 m)	        -f-1
  70 feet  (213 m)  or
    more but leas than
    83 feet (25 3 m)	        +3

§ 325.75  Ground surface correction  fac-
    tors.

  (a) Highway operations. When meas-
urements are made  in accordance with
the rules in subpart D of this Part upon
a test site at which the measurement
area (exclusive of the travelled lane of
the highway and the shoulder of  that
lane)   is  predominantly  covered with
concrete,  asphalt, packed dirt, gravel, or
similar  reflective material, a correction
factor of 2 dB(A)  shall  be subtracted
from the maximum observed sound level
reading generated by the motor vehicle
to determine whether the motor vehicle
conforms to the Standards for Highway
Operations, 40 CPR 202.20.
  (b) Stationary test. When  measure-
ments are made in accordance with the
rules  in subpart E of  this Part upon a
test site at which the measurement area
is  predominantly covered with grass or
other ground cover, a correction factor
of 2 dB(A) shall be added to the numeri-
cal average of the recorded maximum ob-
served sound level readings generated by
the motor vehicle to determine whether
the motor vehicle conforms to the Stand-
ard for Operation Under Stationary Test,
40 CFR 202.21
§ 325.77  Computation of open ailr  re-
    quirements—nonstanrfard sites.
   (a) If the distance between the micro-
phone location  point and  the micro-
phone target point is other  than 50 feet
(152  m.), the test site must be an open
site within a radius from  both points
which is equal to the distance between
Che microphone location point and  the
microphone target point.
   (b) Plan view diagrams of nonstand-
ard test sites are shown in Figures 3 and
4 Figure 3 illustrates a test site which is
smaller than a standard test site and is
based upon a 35-foot (10.7-m.) distance
between the microphone location point
and  the microphone target point. (See
§ 325 79(b) (1) for an example of the ap-
plication  of the correction  factor to a
sound level reading  obtained at such a
site)  Figure 4 Illustrates a test site  which
is larger than a  standard test site and is
based upon a 60-foot (183-m.) distance
between the microphone location point
and the microphone target point. (See
§ 325 79(b> (2) for an example of  the
correction factor to a sound level reading
obtained at such a site.)

                            MICROPHONE
                            TARGET POINT

                            CENTERUNE OF
                            THETRAVELLED
                            LANE OF
                            THEHIGWAY
MEASUREMENT
AREA
 MICROPHONE.
 LOCATION POINT
        (35 FT (107M| DISTANCE BETWEEN
     MICROPHONE LOCATION AND TARGET POINTS)
   COMBINATION
   VEHICLE
MEASUREMENT.
AREA
 MICROPHONE
 LOCATION POINT
                            MICROPHONE
                            TARGET POINT
           NON-STANDARD TEST SITE.
        (60 FT |183M| DISTANCE BETWEEN
      MICROPHONE LOCATION AND TARGET POINTS]
                               FEDERAL REGISTEf, VOl. 40, NO. 41—FRIDAY. FEBRUARY IB. 1975

-------
§ 325.79  Application ef correction fn..
     tors.
  (a) If two correction factors apply to
a measurement, both are applied cumula-
tively.
  (b) The following examples Illustrate
the application of correction factors to
sound level measurement readings-
  (1) Example 1—Highway operations
Assume that a motor vehicle generates a
maximum observed sound level  reading
of 93 dB(A)  during a measurement in
accordance with the rules in subpart D
of this Part.  Assume  also that the dis-
tance between the microphone location
point and the microphone target point
was  35 feet (10.7 m.)  and  that  the
measurement area of the test site was
acoustically  "hard."  eg.,  paved with
asphalt. The  corrected sound level gen-
erated by the  motor vehicle  would  be
88 dB(A). calculated as follows:

 93 dB(A)   Uncorrected reading
—3 dB(A)   Distance correction factor
—2 dB(A)   Ground   surface   correction
           factor

 88 dB(A)   Corrected reading

  (2) Example 2—Stationary test. As-
sume that a motor  vehicle  generates
maximum  sound level  readings which
average 86 dB(A) during a measurement
In accordance with the rules in subpart E
of this Part Assume  also that the dis-
tance between  the microphone location
point and the microphone target point
was 60 feet (18.3 m.). and that the meas-
urement area of the test site was covered
with grass.  The  corrected sound level
generated by the motor vehicle would be
89 dB(A), calculated as follows:
 86 dB(A)  Uncorrected average of readings
+ 1 dB(A)  Distance correction factor
+2 dB(A)  Ground   surface   correction
             factor
 80 dB(A)  Corrected reading
  Subpart G—Exhaust Systems and Tires
§ 325.91  Exliaust systems.
  A motor vehicle does not conform to
the exhaust system requirements of the
Interstate Motor Garner Noise Emission
Standards. 40 CPR 202 22. If Inspection
of the exhaust system of the motor vehi-
cle discloses that the system—
  (a)  Has a defect which adversely af-
fects sound reduction, such as exhaust
gas leaks or alteration or deterioration
of muffler elements;
  (b)  Is not equipped  with either a
muffler or other noise dissipatlve device,
such as a  turbocharger  (supercharger
driven by exhaust gases); or
  (c)  Is equipped with  a  cut-out,  by-
pass, or similar device.
§ 325.93  Tires.
  (a)  Except as provided In paragraph
(b) of this section, a motor  vehicle does
not conform to the tire requirements of
the Interstate Motor Carrier Noise Emis-
sion Standards, 40  CFR 202.23, If Inspec-
tion of  any tire on which the vehicle is
operating discloses that  the tire has a
tread pattern  composed primarily  of
cavities In the tread (excluding slpes and
local Chunking) which are not vented by
grooves to the tire shoulder or circum-
ferentlally to each other around the tire.
  (b) Paragraph  (a) of this section does
not apply  to  a motor vehicle operated
on a tire having  a tread pattern of the
type specified In  that paragraph, if the
motor  carrier who operates the motor
vehicle demonstrates to the satisfaction
of the Director of the Bureau of Motor
Carrier Safety  or  his  deslgnee  that
either—
  (1) The  tire did not have that type of
tread  pattern when  It  was originally
manufactured or newly remanufactured;
or
  (2)  The motor  vehicle  generates  a
maximum  sound  level reading of 90 dB
(A) or less when measured at a stand-
ard test site for  highway operations at
a distance of 50 feet and under the fol-
lowing conditions:
  (1)  The  measurement must be made at
a time and place and under conditions
specified by the Director or his deslgnee.
  (11)  The motor vehicle must be op-
erated on  the same tires that were In-
stalled on it when the Inspection specified
in paragraph  (a)  of this  section oc-
curred.
  (ill)  The motor  vehicle  must be op-'
erated on  a highway  having a  posted
speed limit of more than  35 miles per
hour (56.3 kph).
  (iv)  The  sound level measurement
must  be made while  the motor vehicle
is operating at the posted speed limit
  [FR Doc. 76-6088 Filed 3-37-76:8.46 am]
                               FEDERAL REGISTER, VOL. 40. NO.  41—TODAY. FEBRUARY 28. 197S

-------
8. STATE AND LOCAL ROLES

-------
                                     SECTION 8

                   ROLE OF STATE AND LOCAL GOVERNMENTS
     The interstate motor carrier regulation represents the Federal Government's first major
step to control noise from motor vehicles.  Enforcement of the regulation is the responsibility
of the Department of Transportation's Bureau of Motor Carrier Safety (BMCS). There are
approximately 1,000,000 interstate motor carrier vehicles covered by the regulation; however,
the BMCS has only 123 inspectors throughout the U.S. who are currently inspecting 20 - 25,000
vehicles per year for various types of violations.  Even if they are able to  cover the same number
of vehicles once noise control is added to their duties, they will be inspecting less than 3 percent
of those to be covered by the regulation. Since the number of inspectors will not be increased
for at least another ye^ar, state and local cooperation is essential  to the success of the enforce-
ment effort.
     Any state or locality may enforce the interstate truck regulation once it has been enacted
into law by the jurisdiction.  Many communities already have laws regulating noise from motor
vehicles; and, these need only modify that portion of their ordinances affecting interstate
motor carriers (trucks and buses) over 10,000 pounds to make it conform to the Federal
regulation. (The state or local regulation can also apply to intrastate vehicles, and the same
enforcement procedure may  be utilized to control noise from these sources.)
     The Environmental Protection Agency has noise representatives in 10 regions through-
out the country who can provide assistance to those states and communities desiring it. This
assistance is available both for modifying existing ordinances and for drafting new noise con-
trol laws.  The regional offices can also provide information on the measurement procedure
to be used in determining vehicle compliance with the regulation.
     Since vehicle noise, particularly that from heavy interstate trucks and buses, is a prob-
lem in many areas and, since  state and local cooperation is required for the Federal efforts
to be successful, states and communities are urged to enact and enforce the interstate vehicle
provisions.  The motor carrier regulation  provides the mechanism to reduce the noise impact
on areas adversely affected by interstate vehicles.
     It should be emphasized that, after the effective date of the standards (October 15,
1975), state and local regulations affecting interstate trucks and buses must be identical,
both as to noise levels specified and measurements procedures, or they will be preempted.
The purpose of this is to have a single set of standards truckers must meet throughout the
country.  The EPA regional offices may be contacted for further information on preemption
if a community is uncertain whether its law is in  conformity with the  Federal regulation.
                                        8-1

-------
9. VEHICLE NOISE TEST CENTERS

-------
     The following noise control centers in the United States and
Canada are equipped to measure truck noise and to provide corrective
measures if needed.  Donaldson Co., Inc., International Harvester Co.,
Mack Trucks Inc., Stemco Manufacturing Co. and the White Motor Corpo-
ration are the firms operating the centers.

-------
                         DONALDSON CO., INC.
Delaney and Ahlf
3901 Mercury St.
Bakersfield, Calif. 93308
805/322-5064

Watkins & Meehan
1960 Folsom St.
San Francisco, Calif 94103
415/621-8930

Everroad Supply Co.
5400 E. 56th Ave.
Commerce City, Colorado 80022
303/287-0141

Doering Truck Parts
212 E. State St.
Peoria, 111. 61602
309/654-1621

Service Engineering Co.
5825 W. Ogden Ave.
Cicero, 111. 60650
312/242-3770

AGA Corporation
3758 W. Morris St.
Indianapolis, Ind. 46241
317/248-0327

Indiana Central Engine Co.
7330 W. Chicago Ave.
Gary,  Ind. 46406
219/949-9535

M. M.  Supply Co.
206 12th St.
Des Moines, Iowa 50309
515/288-0192

Northwest  Filter Supply
8890 Wentworth Ave. South
Bloomington, 111. 55420
612/881-5040

-------
Cummins Missouri Diesel
7210 Hall St.
St. Louis, Missouri 63147
314/389-5400

Sleep Mate Products
4319 Northwest Highway-A
Riverside, Missouri 64150
816/741-5875

Everroad Supply Co.
5513 Center St.
Omaha, Neb. 68106
402/556-8921

Ely Motor Supply
201 Ogden Ave.
Ely, Nev. 89301
702/289-4461

Diesel Equipment Company
Box 36
Lafayette Road
Hampton Falls, N.H. 03844
603/926-5859

Laban Equipment Corp.
627 W. Merrick Road
Valley Stream, L.I.,
New York 11580
516/561-2203

King-Mclver Sales, Inc.
Box 20088
Greensboro, N.C. 27420
919/294-4600

Cummins Diesel Sales
4100 W. Main
Fargo, N.D. 58102
701/282-2466

Clarke G. M. Diesel
11536 Gondola St.
Cincinnati, Ohio 45241
513/771-2200

-------
 Big 4  Service  &  Supply
 4314 So.  76th  East Ave.
 Tulsa, Okla. 74145
 918/663-3143

 Safety  Service Company
 15  Fairfield Ave.
 Nashville,  Tenn. 37210
 615/244-2853

 Stewart & Stevenson
 4516 Harrisburg  Blvd.
 Houston,  Texas 77001
 713/923-2161

 Fuel Systems
 12730  Robbins  La.
 Brookfield, Wise. 53005
 414/781-4353

 CANADA

 Downey Supplies  Ltd.
 102 61st  Ave., S.W.
 Calgary,  Alberta
 403/255-6033

 Mil  liam Fleet  Ltd.                  Main Office
 132 W.  2nd Ave.
 Vancouver 10,  British Columbia

 William Fleet  Ltd.                  Branch Office
 1321 Blundell  Road
 Mississauga, Ontario
 416/279-5673

 Ideal  Filter Supply
 584 Roseberry  St.
 Winnipeg, Manitoba
 204/786-6946

Mecho  Supply Ltd.
 1350 Scarth St.
 Regina, Saskatchewan
 306/525-8195

-------
                    INTERNATIONAL HARVESTER CO.
Atlanta Region

International Harvester Company
International Harvester Company
1700 Cherry Street
Knoxville, TN 37917

International  Harvester Company
6020 Adamo Drive
Tampa, FL  36601

International Harvester Company
1315 North Graham Street
Charlotte, NC 28206

Bal timore Region

International Harvester Company
3064 North Boulevard Street
Richmond, VA 23230

International Harvester Company (Baltimore West)
1800 Sulphur Spring Road
Baltimore, MD 21227

International Harvester Company
712 South Cameron Street
Harrisburg, PA 17105

Boston Region

International Harvester Company
Syracuse, New York Branch
105 7th N. & Terminal Road
Liverpool, NY 13210

International Harvester Company
Albany, New York Branch
980 Broadway
Albany, NY 12204

International Harvester Company
North Boston Branch
340 Mystic Avenue
Medford, MA 02155

-------
International Harvester Company
Hartford, CT Branch
130  Brainard Road
Hartford, CT 06114

Chicago Region

International Harvester Company
3333 South Archer Avenue
Chicago, IL 60608

International Harvester Company
420 South First Street
Milwaukee, WI 53204

International Harvester Company
611 Hansen Road
Green Bay, HI 54304

International Harvester Company
South Bend
Indiana Branch
4849 West Western Avenue
South Bend, IN 46619

Cincinnati Region

International Harvester Company
Cincinnati Gest Street Branch
1200 Gest Street
Cincinnati, OH 45203

International Harvester Company
Springfield, Ohio Branch
705 W. Leffel Lane
Springfield, OH 45506

International Harvester Company
Indianapolia West Branch
P.O. Box 41303
Indianapolis, IN 46241

Cleveland Region

International Harvester Company
Detroit Branch
4840 Wyoming
Dearborn, MI 48126

-------
International Harvester Company
Buffalo Branch
2335 Fill more Avenue
Buffalo, NY 14214

International Harvester Company
Cleveland/East Branch
6100 Canal Road
Valley View, OH 44125

International Harvester Company
Pittsburgh Branch
1 301 Beaver Avenue
Pittsburgh, PA 16230

Dallas Region

International Harvester Company
4619 Navigation Blvd.
P.O. Box 3050
Houston, TX 77011

International Harvester Company
3722 Irving Blvd.
Dallas, TX 75247

International Harvester Company
1735 West Reno
Oklahoma City, OK 73106

International Harvester Company
715 Steves Avenue
San Antonio, TX 78210

International Harvester Company
1924 Second Street, N.W.
Albuquerque, flM 87103

Kansas City Region

International Harvester Company
1910 East Euclid
Des Moines, IA 50313

International Harvester Company
3701 Chouteau
St. Louise, MO

-------
 International Harvester Company
 1608 Charlotte Street
 Kansas City, MO 64108

 International Harvester Company
 3280 Brighton Blvd.
 Denver, CO

Memphis Region

 International Harvester Compnay
1 750 East Brooks Road
Memphis, TN 38116

 International Harvester Company
5000 Gentilly Road
New Orleans, LA 70126

 International Harvester Company
 711 Murfreesboro Road
Nashville, TN 37210

Oak! and Region

 International Harvester Company
 390 Doolittle Drive
 San Leandro, CA 94577

International Harvester Company
4501 South Alameda Street
 Los Angeles, CA 90058

International Harvester Company
 317 South Ninth Avenue
 Phoenix, AZ 85007

International  Harvester Company
 2712 South Fourthe Street
 Fresno, CA 93725

International Harvester Company
409 West Fourth South
Salt Lake City, UT 84101

International Harvester Company
2445 Evergreen Street
W. Sacramento, CA 95691

-------
Philadelphia Region

International Harvester Company
Newark Branch
41-85 Doremus Avenue
Newark, NJ 07105

International Harvester Company
Allentown Branch
728 Union Blvd.
Allentown, PA 18103

International Harvester Company
Philadelphia East Branch
4298 Macalester Street
Philadelphia, PA 19124

Portland Region

International Harvester Company
635 N.E. Second Avenue
Portland, OR 97232

International Harvester Company
917 First Avenue North
Billings, MT 59101

International Harvester Company
715 E. Sprague Avenue
Spokane, WA 99220

Twin Cities Region

International Harvester Company
3000 Broadway Street Northeast
Minneapolis, MN 55413

International Harvester Company
925 Dace Street
Post Office Box 717
Sioux City,  IA 51102

International Harvester Company
775 Rice Street
Saint Paul, MN 55117

-------
Kansas City Region

International Harvester Company
1770 N. Broadway
Witcha, Kansas 67214

International Harvester Company
500 E. 10th Street
Topeka, Kansas 66607

International Harvester Company
320 W. Broadway
St. Louis, Missouri 63147

International Harvester Company
3250 Harvester Road
Kansas City, Kansas 66115

International Harvester Company
1529 E. Chestnut Street
Springfield, Missouri 65801

International Harvester Company
2500 S. 4th Street
St. Joseph, Missouri 64501

International  Harvester Company
3131 Corn Husker Highway
Lincoln, Nebraska 68501

International Harvester Company
110 & J Street
Omaha, Nebraska 68137

International Harvester Company
2740 6th Street Road S.W.
Cedar Rapids, Iowa 52404

-------
                          MACK TRUCKS. INC
Alabama

Mack Trucks, Inc.
3101 Airport Highway
P.O. Box 10125
Birmingham, 35202

California

Motor Truck Distributors Co.
220 Rexford Drive
Col ton, 92324

Motor Truck Distributors Co.
2940 Broadway
P.O. Box 4569
Eureka, 95501

Motor Truck Distributors Co.
2340 East Olympic Blvd.
P.O. Box 21916
Los Angeles, 90021

Motor Truck Distributors Co.
425 Market Street
P.O. Box 2040
Oakland 94604

Motor Truck Distributors Co.
3333 S. Market St.
P.O. Box 1985
Redding, 96001

Motor Truck Distributors Co.
301 Broadway
P.O. Box 8109
Sacramento, 95818

Motor Truck Distributors Co.
55 E. Brokaw Road
San Jose, 95112

Motor Truck Distributors
2800 Cherry Avenue
P.O. Box 2899
Signal  Hill, 90806

-------
Colorado

Mack Trucks, Inc.
4850 Vasquez Blvd.
P.O. Box 16364
Stockyard Station
Denver, 80216

Florida

Mack Trucks, Inc.
2203 West Beaver Street
P.O. Box 2880
Jacksonville 32203

Georgia

Mack Trucks, Inc.
780 Memorial Drive, S.E.
P.O. Box 18027
Atlanta, 30316

Mack Trucks, Inc.
Conley Used Truck Center
4570 Moreland Avenue
P.O. Box 299
Conley, 30027

Hawaii

Motor Truck Distributors Co.
231 Sand Island Access Road
Honolulu, 96819

IIlinois

Mack Trucks, Inc.
3300 S. Wentworth Avenue
Chicago, 60616

Indiana

Mack Trucks, Inc.
1810 W. 16th Street
Indianapolis, 46202

Kentucky

Mack Trucks, Inc.
1820 Arthur Street
Louisville, 40217

-------
 Louisiana

 Mack Trucks, Inc.
 110 E. Airline Highway
 P.O. Box 887
 Kenner, 70062

 Massachusetts

 Mack Trucks, Inc.
 75 North Beacon Street
 Boston, 02134

 Michigan

 Mack Trucks, Inc.
 10401  Ford Road
 P.O. Box 490
 Dearborn, 48121

 Minnesota

 Mack Trucks, Inc.
 21 95 West County  Road  C2
 P.O. Box 3579
 St.  Paul, 55165

 Missouri
Mack  Trucks,  Inc.
3738  Gardner  Avenue
Kansas  City,  64120

Mack  Trucks,  Inc.
2350  Chouteau Avenue
St. Louis, 63103

Nebraska
Mack Trucks, Inc.
7210 "L" Street
Omaha, 68137

New Jersey

Mack Trucks, Inc.
480 Mundet Place
Hillside, 07205

-------
New Mexico

Mack Trucks, Inc.
2941 East Main Street
P.O. Box 214
Farmington, 87401

New York

Mack Trucks, Inc.
1064 Broadway
P.O. Box 1152
Albany, 12201

Mack Trucks, Inc.
Erie Blvd., East
P.O. Box 279
East Syracuse, 13057

Mack Trucks, Inc.
58-40 Borden Avenue
Maspeth, 11378

Mack Trucks, Inc.
205 Del afield Street
P.O. Box 471
Poughkeepsie, 12602

North Carolina

Mack  Trucks, Inc.
228 Dal ton Avenue
P.O. Box 1967
Charlotte, 28201

Mack Trucks, Inc.
201 Waughtown Street
P.O. Drawer E, Salem Station
Winston-Sal em, 27108

Ohio

Mack Trucks, Inc.
Akron Used Truck Center
1 237 S. Arlington St.
P.O. Box 7057
Akron, 44306

Mack Trucks, Inc.
1100 Triplett Blvd.
P.O. Box 7155
Akron, 44306

-------
Mack Trucks, Inc.
1223 West Eighth Street
P.O. Box 14526
Cincinnati, 45203

Mack Trucks, Inc.
13600 Broadway
Cleveland, 44125

Marietta Truck & Trailer Repairs
813 Gilman Street
Marietta, 45750

Oklahoma

Mack Trucks, Inc.
3200 West Reno Avenue
Oklahoma City, 73107

Oregon

Automotive Equipment Company
933 Franklin Blvd.
P.O. Box 1108
Eugene, 97401

Automotive Equipment Company
5030 Crater Lake Highway
Medford, 97501

Automotive Equipment Company
5411 No. Lagoon Avenue
Portland, 97217

Pennsylvania

Mack Trucks, Inc.
Rts. 22 & 309
P.O. Box A
Allentown, 18105

Mack Trucks, Inc.
2020 Paxton Street
P.O. Box 1643
Harrisburg, 17105

Mack Trucks, Inc.
Bl ue Grass Road & Grant Avenue
Philadelphia, 19114

Mack Trucks, Inc.
1 501 Beaver Avenue
Pittsburgh, 15233

-------
Rhode Island

Mack Trucks, Inc.
190 Service Avenue
P.O. Box 152
Warwick,02886

Texas

Mack Trucks, Inc.
3611 Irving Blvd.
P.O. Box 47107
Dallas, 75247

Mack Trucks, Inc.
5331 Gulf Freeway
P.O. Box 18515
Houston, 77023

Utah

Mack Trucks, Inc.
704 South 4th West
Salt Lake City, 84101

Virginia

Mack Trucks, Inc.
1705 Commerce Road
P.O. Box 4160
Richmond, 23224

Washington

Automotive Equipment Company
2025 Airport Way South
Seattle, 98134

-------
                        WHITE MOTOR CORPORATION
Alamo White Truck Services, Inc.
San Antonio, Texas

Arkansas White
Springdale, Arkansas

Baumert Sales
Hartford, Connecticut

Boise White Truck
Boise, Idaho

Chattanooga White Trucks
Chattanooga, Tennessee

Chesley Co.
Waterloo, Iowa

B. H. Chesley White
Mankato, Minnesota

Contractors Equip. & Supply
Albuquerque, New Mexico

Corley-Wetsel White
Abilene, Texas

Delta White Truck Sales
Stockton, California

Detroit White Autocar
Detroit, Michigan

Fox & James White Trucks
Latrobe, Pennsylvania

Ft. Worth White Trucks
Ft. Worth, Texas

Fulton White
Roanoke, Virginia

Fyda White Trucks
Youngstown, Ohio

Hall & Fuhs,  Inc.
Mountainside, New Jersey

-------
Hill White Truck
South Bend, Indiana
Hodges Tire & White
Wichita Falls, Texas
Lucas White
Charlotte, North Carolina
Nebraska White Trucks
Grand Island, Nebraska
Mew Orleans White Trucks
New Orleans, Louisiana
Sacramento White Trucks
W. Sacramento, California
Salina White Trucks
Sal ina, Kansas
Tinder White Trucks
Bluefield, West Virginia
Truck & Trailer Sales
Savannah, Georgia
West Texas White Trucks
Odessa, Texas
Western Ohio White
Toledo, Ohio
Wichita  White Trucks
Wichita, Kansas
WorChester White Autocar
Worcester, Massachusetts
B. H. Chesley Co.
Fargo, North Dakota
Sterling Truck Sales Co.
Larksvilie, Pa.

-------
                      WHITE MOTOR CORPORATION
Akron
Akron, Ohio

Atlanta
Atlanta, Georgia

Baltimore
Baltimore, Maryland

Birmingham
Birmingham, Alabama

Chicago Southside
Chicago, Illinois

Charlotte Region
Charlotte, North Carolina

Cleveland
Cleveland, Ohio

Dallas
Dallas, Texas

Dallas Region
Dallas, Texas

Denver
Denver, Colorado

Hou ston
Houston, Texas

Jacksonville
Jacksonville, Florida

Kansas City
Kansas City, Missouri

Kansas City Region
Kansas City, Missouri

Los Angeles
Los Angeles, California

-------
Ft. Lauderdale
Ft. Lauderdale, Florida

Mewa rk
Newark, New Jersey

New York Region
New York, New York

Oakland
Oakland, California

Oklahoma City
Oklahoma, Oklahoma

Philadelphia
Philadelphia, Pennsylvania

Portland
Portland, Oregon

St. Louis
St. Louis, Missouri

Winston-Sal em
Kernersville, North Carolina

-------
                   STEMCO MANUFACTURING  COMPANY


 Alabama

 Diesel  Equipment  Co.,  Inc.
 Birmingham

 Truck  Parts  &  Equipment  Company
 Birmingham

 Peter's  Garage,  Inc.
 Dothan

 Fleet  Parks  and  Equipment
 Montgomery

 Tri-City Truck Parts
 Muscle Shoals

 Arizona

 Motor  Rim  &  Wheel  Service
 Phoenix

 Wheel  Industries
 Tempe

 Arkansas

 Holt White Trucks, Inc.
 Little Rock

 T&T Parts  Warehouse, Inc.
 Little Rock

 California

 Truck and  Auto Supply
 Anaheim

 Triangle Truck Parts
 Azusa

 Franks Brake Service
 Bakersfield

 San Gabriel Valley Truck Parts
 Baldwin Park

 Bob Wymore Service
Chino

Truck and Auto Supply Co.
Escondido

-------
Stemco Manufacturing Co.,  Inc. - Cont'd

California - Cont'd

Motor Rim and Wheel Service
Fresno

So-Cal White Trucks
Long Beach

Mack Trucks of Los Angeles
Los Angeles

Wheel Industries - Div. of Budd Co.
Los Angeles

Motor Rim & Wheel Service
Montebello

Engs Motor Trucks
Pico Rivera

E. M. Tharp Co., Inc.
Porterville

Mack Trucks Inc.
Redding

Pacific Coast Truck Repair, Inc.
Richmond

Mack Trucks Inc.
Sacramento

Norm Presley Truck Center
San Diego

Motor Rim & Wheel Service
San Diego

Motor Rim & Wheel
San Leandro

Brakes & Alignment Co., Inc.
San Jose

Colorado

Elder/Quinn & McGill,  Inc.
Denver

-------
 Stemco Manufacturing  Co.,  Inc.  -  Cont'd

 Connecticut

 Connecticut Drive Shaft Co.,  Inc.
 Mi 1 ford

 Connecticut Wheel  and Rim  Co.
 New Haven

 Delaware

 Brake  & Equipment Co.
 Dover

 Brake  & Equipment Co.
 Wilmington

 Florida

 American Trucking  Equipment Co.
 Jacksonville

 Fleet  Supply,  Inc.
 Tallahassee

 Clutch  and Gear  Inc.
 Tampa

 Idaho

 Bob & John's,  Inc.
 Caldwell

 Eastern Idaho  Diesel
 Idaho Falls

 Illinois

 Schien  Body &  Equipment Co.
 Carlinvilie

 Merit Truck Parts & Wheel Co.
 Chicago

 All Brake & Drive Unit Service, Inc.
 Cicero

 Mutual  Wheel Company
 Moline

 Illinois Wheel & Brake
 Springfield

 Botts Welding & Truck Service, Inc.
Woodstock

-------
Stemco Manufacturing Co., Inc. - Cont'd
Indiana
Auto Wheel & Rim Service Co., Inc.
Evansville
Indiana Wheel & Rim
Indianapolis
Wheel and Rim Sales Co.
Ft. Wayne
Gail Catt Sales
Vincennes
Whiteford Sales and Service
South Bend
Iowa
Midwest Wheel & Rim Co.
Davenport
Des Moines Wheel & Rim Co.
Des Moines
Midwest Wheel & Rim Co.
Dubuque
Mutual Wheel Co.
Dubuque
Kansas
Sam Brown Co.
Kansas City
Borbein, Young & Company
Wichita
Kentucky
Auto Wheel and Rim Service
Bowling Green
Trucks Parts & Equipment
Lexington
Auto Wheel & Rim Service
Louisville
Cummins Diesel Sales of Louisville, Inc
Louisville

-------
 Stemco Manufacturing Co.,  Inc.  - Cont'd
 Louisiana
 Precision Brake & Clutch,  Inc.
 Baton Rouge
 Louisiana Brake & Clutch,  Inc.
 New Orleans
 Southern Wheel & Rim
 New Orleans
 Maine
 New England Wheel of Maine
 Portland
 Maryland
 Chesapeake Rim & Wheel Distrs., Inc.
 Baltimore
 Wareheim Air Brakes, Inc.
 Baltimore
 Air Brakes & Control of D.C., Inc.
 Bladensburg
 Brake & Equipment Co.
 Salisbury
 Massachusetts
 New England Wheel & Rim
 Boston
 Brake & Electric Sales
 Medford
 New England Wheel and Parts
 West Springfield
 Michigan
 L&M Truck Parts
 Detroit
 Nu-Way Brake & Equipment
 Detroit
 Road Equipment Truck Service
Grand Rapids
Michigan Truck Equipment
Saginaw

-------
 Minnesota

 Wheel  Service  Co.,  Inc.
 St.  Paul

 Mississippi

 Precision  Brake  & Clutch
 Jackson

 Missouri
Borbein,  Young  & Co.
Springfield

Borbein,  Young  & Co.
St.  Louis

Plaza Automotive,  Inc.
St.  Louis

Montana
Montana Wheels & Equipment
Billings

Northwest Wheel, Inc.
Great Falls

Nebraska

Morgan Wheel & Equipment Co.
Omaha

Nevada

Jordan's Thermo-King
Reno

New Hampshire

Brake & Electric Sales Corp.
Manchester

New Jersey

Guy's Brake Service
Pennsauken

Kay Wheel  Sales Co.
Vine!and

-------
Stemco Mfg. Co - Cont'd

New York

Heavy Duty Truck Parts Warehouse
Buffalo

A.C.I. Supply Co.
Elmira

Frey The Wheel Man
Rochester

Laban Equipment Corp.
Valley Stream

North Carolina
Carolina Rim & Wheel Co.
Charlotte

Salem Spring Co. of Charlotte
Charlotte

Brake and Spring Service
Greensboro

Bales & Truitt Co.
Kernersville

Raleigh Spring and Brake Service
Raleigh

Brake and Spring Service
Wilmington

North Dakota

Wheel Service Co., Inc.
Fargo

Ohio

Cummins Diesel of Northern Ohio
Akron

Wheel and Rim Sales Co.
Akron

Cramer Deluxe Sales, Inc.
Akron

Young White Trucks, Inc.
Canton

Rim and Sales Service Inc.
Cincinnati

-------
Stemco Mfg. Co. - Cont'd

Ohio - Cont'd

Wheel and Rim Sales Co.
Cleveland

Carnegie Body Co.
Cleveland

Custom Maintenance Service
Circleville

Wheel and Rim Sales Co.
Circleville

Hogan Transportation Equipment
Columbus

Hogan Transportation Equipment
Dayton

Defiance Mack Sales and Service
Defiance

O.S. Hill & Co.
East Liverpool

CR&M, Inc.
Gal ion

Commercial Truck & Trailer, Inc.
Girard

Lima Mack Sales & Service, Inc.
Lima

Wheel and Rim Sales Co.
Perrysburg

Glockner Supply Co.
Portsmouth

Lojek's Sales & Service
Richfield

Gipson Bearing & Supply Co.
Steubenville

Knauer Supply Company
Toledo

Toledo Mack Sales & Service
Toledo

Southwest Truck Parts Co.
Wooster

-------
Stemco Mfg. Co. - Cont'd

Oklahoma
Perfection Equipment Co.
Oklahoma City
Oregon
Myrmo & Sons, Inc.
Eugene
Auto Wheel Service, Inc.
Portland

Cummins Oregon Diesel, Inc.
Portland

Pennsylvania

Commercial Parts Div. of Bethlehem
Bethlehem

Brake Drum & Equipment Company
Clearfield

Kay Wheel Sales Co.
Cornwells Heights

Fleet Sales & Parts Co.
Erie

Reslink & Wiggers Truck Parts, Inc.
Erie

Wheel and Rim Sales Co.
Parrel!

Brake Drum & Equipment Co.
Greensburg

Standard Wheel
Harrisburg

United Equipment, Inc.
Philadelphia

Brake Drum & Equipment Co.
Pittsburgh

Stewart Speedometer Service
Youngwood

-------
 Stemco Mfg.  Co.  - Cont'd

 Rhode  Island

 Brake &  Electric Sales Corp.
 Providence

 New  England  Wheel and Rim
 Providence

 South Dakota

 Godfrey's Brake  Service
 Rapid City

 Holcomb  White  Trucks, Inc.
 Sioux Falls

 Tennessee

 Wheels & Brakes, Inc.
 Kingsport

 Wheels & Brakes, Inc.
 Knoxville

 Haygood, Inc.
 Memphis

 Memphis  White Trucks, Inc.
 Memphis

 Safety Service Co., Inc.
 Nashville

 Texas

 Southwest Wheel, Inc.
 Beaumont

 E. G. Boyd Trailer Co,
 Dallas

 Houston  Trailer & Truck Body, Inc.
 Houston

 Southwest Wheel, Inc.
 Houston

 Southwest Wheel, Inc.
 San Antonio

Ludwell  & Sons, Inc.
Texarkana

-------
 Stemco  Mfg. Co.  -  Cont'd

 Utah

 Page  Brake
 Salt  Lake City

 Henderson Wheel  and Warehouse  Supply
 Salt  Lake City

 Virginia

 Standard Parts Corp.
 Chesapeake

 Standard Parts Corporation
 Richmond

 Dixie Wheel Co.
 Richmond

 Standard Parts Corporation
 Roanoke

 Washington

 Fleet Equipment, Inc.
 Seattle

 Bearing & Rim Supply Co.
 Spokane

 Rockwell Northwestern Ltd.
 Vancouver

 West  Virginia

 Wheel and Rim Sales Co.
 Fairmont

 Power Supply Co.
 Wheeling

 Wisconsin

 Wisconsin Wheel & Rim
 Appleton

 Truck Equipment,  Inc.
 Green Bay

Wisconsin Wheel & Rim
Milwaukee

-------
Stemco Mfg. Co - Cont'd
Vlyomi ng
Elder/Quinn & McGill, Inc.
Casper

-------
10. LOW-NOISE EQUIPMENT
    MANUFACTURERS

-------
1.  Aeroquip
    Jackson, Michigan  49203
    Exhaust Systems

2.  Stemco Mfg. Company, Inc.
    P. 0. Box 1989
    Longview, Texas  75601
    Mufflers, Exhaust Systems, In Cab Noise Control

3.  Parker-Hannifin Corp.
    Cleveland, Ohio
    Hydraulic Systems, Noise

4.  Speciality Composites Corp.
    Newark, Delaware
    Acoustical Floormats

5.  Cowl, Division of James B. Carter Ltd.
    88 Fennel1 Street
    Winnipeg, Manitoba, Canada  R3T3M4

6.  Riker Manufacturing, Inc.
    4901 Stickney Avenue
    Toledo, Ohio  43612
    Mufflers

7.  Donaldson Co., Inc.
    P. O. Box 1299
    Minneapolis* Minnesota  55440
    Exhaust Systems

8.  Arvin Industries, Inc.
    Automotive AfterMarket Division
    Columbus, Indiana  472O1
    Mufflers

9.  H. L. Blaekford, Inc.
    1855 Stepheson Highway
    Troy, Michigan  48O84
    Acoustical Panels, Enclosures, etc.

-------
11. TECHNICAL DATA

-------

-------
                             EPA-550/9-74-017
        BACKGROUND DOCUMENT
                  FOR
    INTERSTATE MOTOR CARRIER NOISE
         EMISSION REGULATIONS
             OCTOBER 1974
             PREPARED BY
U.S. Environmental Protection Agency
      Washington, D.C. 20460
           This document has been approved for general
           availability It does not constitute a standard,
           specification or regulation.

-------
                       TABLE OF CONTENTS
SECTION 1.   EPA STRATEGY FOR CONTROL OF MEDIUM AND
             HEAVY DUTY MOTOR VEHICLE NOISE	       1
    Noise Levels Protective of Public Health and Welfare	       1
    Actual Noise Levels in Residential Areas  	       3
    EPA Regulatory Strategy for Motor Vehicles	       3
    Rationale for the CoveraRc of Vehicles Over 10,000 Pounds
    GVWR/GCWR	       6

SECTION 2.   TECHNOLOGY AND COST OF QUIETING IN-SERVICE
             MOTOR VEHICLES	       8
    General  Characteristics of Large Trucks  	       9
    Component Noise Sources and Quieting Techniques	      10
        Exhaust System	      14
        Cooling Fan	      15
        Engine  (Mechanical)   	      16
        Air  Induction System	      17
        Tire/Roadway Interaction	      18
    Cost of Retrofitting Individual Trucks	      19
        Technology and Cost Required to Comply with a Low-Speed
        Standard  	      21
        Technology and Cost Required to Comply with a High-Speed
        Standard  	      25

-------
                    TABLE OF CONTENTS (CONT)
                                                                Page
SECTION 3.   INTERSTATE MOTOR CARRIER REGULATIONS  ...    27
    Summary of the Regulations  	    27
    Revision of the Proposed Regulations Prior to Promulgation ...    2H
        Preemption  	    32
        Enforcement Procedures, Violations, and Penalties	    35
    Relationship between Low-Speed Measurement Procedures ....    35
    Stationary Run-Up Test Correlation with SAE J366a	    *2

SECTION 4.   NOISE  MEASUREMENT OF IN-SERVICE VEHICLES..    44
    Measurement Methodology	   44
    Surveys of Truck Noise   	    45
                                                                 A *7
    Analyses of High Speed (Over 35 MPH) Survey Data  	
    Analysis of Low Speed (Under 35 MPH) Survey Data	   56
    Analysis of Stationary Runup Test  Data	   56
    Classification of Trucks into Categories	    59
    Potential Degradation of Vehicles	    g2

SECTION 5.  IMPACT  OF THE FEDERAL NOISE REGULATIONS.  .   6'1
    Economic Impact of the Regulations	   G4
    Environmental Impact of the Noise Emission Standards	   66
    Relative Stringency of Federal Regulations and Those of Other
    Jurisdictions   	    63
                                 11

-------
                   TABLE OF CONTENTS (CONT)






REFERENCES  	    72






APPENDIX:  MEASUREMENT METHODOLOGY	    76



    Applicable Documents 	    76



    Instrumentation  	    7t



    Calibration	    77



    Standard Measurement Site	    77



    Weather	    73



    Microphone Location	    7



    Noise Measurement Procedures	    73
                               iii

-------
                               Section 1
      EPA STRATEGY FOR CONTROL OF MEDIUM AND HEAVY DUTY
                       MOTOR VEHICLE NOISE

    In March, 1974, in accordance with Section 5(a)(2) of the Noise Control
Act of 1972, EPA published a document in which levels of environmental noise
requisite to protect public health and welfare were identified  .   Since EPA
studies have shown that actual environmental noise levels in many parts of
the country exceed the levels identified as  desirable, a Federal strategy is
being developed to control environmental noise.
NOISE LEVELS PROTECTIVE OF  PUBLIC HEALTH AND WELFARE
    As part of the identification of noise levels protective of public health and
welfare,  EPA has selected the noise measures it believes are most useful for
describing environmental noise and its effects on people.
    Environmental noise is defined in the Noise Control Act as "the intensity,
duration and the character of sounds from all sources. "  The measures for
characterizing environment noise must, therefore, evaluate these factors.
However,  the measures must also  predict human response and be simple to
monitor if they are to be useful. EPA has chosen two  cumulative equivalent
sound level measures as its  basic indicators of noise that constitutes a long-
term  hazard to public health and welfare.  The first measure is the equivalent
sound level (L  ), which is the constant sound level (dBA) that in  a given situa-
tion and time period would convey the  same sound energy as does the actual
time-varying sound; L  is used as an indicator of long-term hazard to hearing.
A variation of L   , the day-night sound level (L, ) is the equivalent sound level
               cq                           an
during a 24 hour period with a 10 dB(A) penalty added to events occurring
between the hours of 10 p.m. and 7 a.m.  to account for the increased annoyance
caused by noise at night; L,   is used as an indicator of long-term annoyance.

-------
    The relationships between environmental noise and human response have
been quantified using the simple measures described above.  The human
response examined was a combination of such factors as hearing interference,
sleep interference, speech interference, desire for a tranquil environment
and the ability to use telephones, radios,  and TV satisfactorily.
    The levels identified by EPA as desirable from a public health and welfare
viewpoint are predicated on minimizing the average number of people who may
experience an adverse reaction to noise as a result of extended exposure.
However,  different individuals do  not have the same susceptibility to noise.
Even groups of people may vary in response depending on previous exposure,
age, socio-economic status, political cohesiveness and other social variables.
In the aggregate, however, the average response of groups of people is predic-
table and related to cumulative noise exposure as expressed by L,   or L  .
                                                            on     eq
    Detailed discussions of the relationships between environmental noise and
human response is provided in the EPA document Information on Levels of
Environmental Noise Requisite to  Protect Public Health and Welfare with an
Adequate Margin of Safety.  Desirable outdoor noise levels are summarized in
Table 1 in terms of yearly equivalent levels which, if not exceeded, would be
safe from a health and welfare viewpoint. Public health and welfare for the
purpose of this analysis was defined so as to include personal comfort, well-
being,  and the absence of clinical  symptoms.
                                TABLE 1
SUMMARY OF NOISE LEVELS IDENTIFIED AS REQUISITE  TO PROTECT
PUBLIC HEALTH AND WELFARE WITH AN ADEQUATE MARGIN  OF SAFETY.

    Effect                   Level in dB                     Area
    Hearing                L   0,. £ 70                  All Areas
      Loss                    eq(Z4)
    Activity Interference      L.  £ 55                    -Residential
      Outdoors                                             Areas

-------
ACTUAL NOISE LEVELS IN RESIDENTIAL AREAS
    Studies have been performed to measure the noise levels in residential
areas and to estimate the number of people subjected to noise in those areas.
Table 2 contains estimates of the number of people residing in urban areas
which are exposed to noise principally caused by urban traffic, freeway
traffic, and aircraft operations.

                                TABLE 2
       ESTIMATED CUMULATIVE NUMBER OF PEOPLE IN MILLIONS
IN THE UNITED STATES RESIDING IN URBAN AREAS WHICH ARE EXPOSED
 TO VARIOUS LEVELS OF OUTDOOR DAY/NIGHT AVERAGE SOUND LEVEL(3)
Outdoor
L, Exceeds
dn
60
65
70
75
80
Urban
Traffic

59.0
24.3
6.9
1.3
0.1
Freeway
Traffic

3.1
2.5
1.9
0.9
0.3
Aircraft
Operations

16.0
7.5
3.4
1.5
0.2

Total

78.1
34.3
12.2
3.7
0.6
The data in the table clearly indicate that motor vehicles are the principal
source of environmental noise In urban areas.
EPA REGULATORY STRATEGY FOR MOTOR VEHICLES
    Accordingly,  EPA has developed a regulatory strategy that places high
priority on the control of motor vehicle noise.  As part of the development
of the strategy, studies were performed for EPA that provide information
on the relative noise contribution of different kinds of motor vehicles to
traffic noise levels in urban areas.  Table 3 gives information on the typical
sound level at 50 feet of seven types of motor vehicles and also indicates the

-------
estimated total daily sound energy emitted into the environment by all in-
service vehicles of each type.  For the purpose of the analysis, trucks and
automobiles were divided into groups having different noise emission and
technology characteristics.  Light trucks were separated from medium and
heavy duty trucks because they have a higher power-to-weight ratio and are
quieter in normal operation.  Large passenger cars were separated from
compact and sports  cars for the same reason.
Motor Vehicles
 TABLE 3

Typical Sound Level
dB (A) at 50 feet
Estimated Total
Sound Energy
KW-Hrs/Day
1.
2.
3.
4.
5.
6.
7.
Trucks (medium & heavy)
Automobiles (sports, compacts)
Automobiles (passenger)
Trucks (light, pickup)
Motorcycles (highway)
Buses (city and school)
Buses (highway)
84
75
69
72
82
73
82
5800
1150
800
570
325
20
12
    The sound level (dB(A)) at 50 feet is a measure that suggests which motor
vehicles will be perceived as noisy by the community when they are operated
alone.  The daily total sound energy emission is useful because it is an
aggregate measure that takes into account the sound  energy emission rate of
the vehicle, the number of vehicles operating, and the amount of time they
arc operated each day.  Neither measure directly relates human exposure or
response to the vehicle's noise emission; but when several kinds of vehicles
are operated in similar situations, these two measures serve to indicate  which
are the major sources of noise.

-------
    The (1,'ilii in Tsible X clearly indicates that medium and heavy duty trucks
contribute more soumf energy to the environment than any other type of high-
way vehicle and that an individual truck will typically be perceived to be
louder than some other type of motor vehicle. These values are a composite
of noise emitted in both urban traffic conditions and on freeways, and there
can be little doubt that medium and heavy duty trucks are the major contributor
to traffic noise in many situations.
    The Noise Control Act contains two sections of primary importance for
the control of motor vehicle noise.  Section 6 contains authority by which EPA
may promulgate product  noise emission standards for new motor vehicles
that are applicable at the time of sale of such vehicles.
    Section 18 of the Act requires EPA to promulgate noise emission regula-
tions that  include "noise  emission standards setting such limits on noise
emissions  resulting from operation of motor carriers engaged  in interstate
commerce which  reflect  the degree of noise reduction achievable through the
application of the best available technology, taking into account the cost of
compliance.1'
    Accordingly, EPA has developed and is now implementing  a motor vehicle
noise control strategy based on sections 6 and 18 of the Act that should prove
to be effective in  reducing environmental noise  in many areas to the levels
identified as protective of public health and welfare. The strategy calls first,
lor the reduction, within one year of the promulgation of these  regulations under
section 18, of the noise from vehicles over  10,000 pounds GVWR/GCWH oper-
ated by motor carriers engaged ia Interstate commerce, to the lowest noise level
consistent with the  noise abatement technology  available for retrofit application
flurmg the one year period,  taking into account  the cost of compliance.
    Subsequently, under section fi, new product noise emission standards will
be proposed for medium  and heavy duty trucks, and  it is contemplated that
the new product standards will be maintained for new trucks beyond the initial
point of sale through subsequent modification of these initial Interstate Motor
Carrier Regulations pursuant to section 18 to require that vehicles manufactured

-------
to comply with new product performance standards and used in interstate com-
merce shall maintain the lower noise emission levels during operation.
    Additionally, it is  anticipated that the performance standards in the inter-
state motor carrier regulations relating to older vehicles will be made more
stringent as more advanced retrofit technology becomes available and the cost
of compliance permits.
    The effect of the initial Interstate Motor Carrier Regulations will be
noticeable principally around highways.  The principle  noise reduction will be
of the intrusive "noise  peaks," which have been widely  acknowledged as more
                                                             IA\
objectionable to people than much lower levels of continuous noise*  .   However,
the reduction of traffic noise to levels protective of public health and welfare is
not feasible through retrofit programs alone and must await the replacement of
the current vehicle population by new quiet vehicles in conformance with noise
standards promulgated under Section 6.
RATIONALE FOR THE COVERAGE OF VEHICLES OVER 10, OOP POUNDS GVWR/GCWR
    Prior to proposing regulations applicable only to vehicles over  10,000 pounds
GVWR/GCWll, the Agency analyzed both the relative noise contribution to traffic
noise levels and the typical use patterns of different kinds of motor  vehicles.
Light trucks and automobiles were separated from medium and heavy duty trucks
for the analysis because they have a higher power-to-weight ratio,  they are
quieter in normal operation, and they have different uses than larger vehicles.
    In addition to their higher noise emissions, medium and heavy duty motor
vehicles are distinguished from lighter vehicles by their typical use for long
distance intercity and interstate hauling.  They are,  therefore, operated many
more miles per year on the average than light duty vehicles,  which are normally
used for general service and delivery work within a relatively small area.
    Medium as well as heavy duty motor vehicles operated by interstate motor
carriers are in significant numbers constantly in transit between different
jurisdictions, and it would be impractical for them to comply with a different
noise emission standard in different jurisdictions.  Thus,  "medium duty" as

-------
well as "heavy duty" motor vehicles operated by interstate motor carriers
are construed by the Agency to be "major noise sources in commerce control
of which require uniform national treatment" under section 18 of the Noise
Control Act.
     Conversely, since light duty vehicles are typically used for general
service and delivery work within relatively small areas and are not usually
subject to the noise emission regulations of many different jurisdictions,
national uniformity of treatment of the noise emission resulting from their
operation  does not appear essential at this time.
     The specification of a precise delineation between "light duty" or "small"
vehicles and  "medium and heavy duty" vehicles for purposes of regulation is
largely an exercise of technical judgment.  EPA has  chosen to make that deline-
ation at 10,000 pounds GVWR/or GCWR in these regulations.
     A break  at 10,000 pounds GVWR/GCWR is also convenient because most states
use that weight rating as a distinction in their vehicle registration  categories.
The Department of Commerce nnd the Motor Vehicle Manufacturers
Association divide lighl. duty and medium duty vehicles at that weight rating.
In addition, it is a standard weight category distinction used by the Department
of Transportation in their safety regulations, and compatibility of the Inter-
state Motor Carrier Regulations with the present DOT weight categories  is
advantageous because DOT is the Federal enforcement agent.

-------
                                Section 2

 TECHNOLOGY AND COST OF QUIETING IN-SERVICE MOTOR VEHICLES

    Section 18(a)(l) of the Noise Control Act requires that noise emission
standards pursuant to that part set limits  on noise emissions resulting from
the operation of motor carriers which "... reflect the degree of noise
reduction achievable through the application of best available technology,
taking into account the cost of compliance. "
    In order to implement this section of the Act, "best available technology"
and "cost of compliance" have been defined as follows:
         "Best available technology" is that noise abatement technology
    available for retrofit application to motor vehicles that produces mean-
    ingful reduction in the noise produced by vehicles used by motor carriers
    engaged in interstate commerce.  "Available" is further defined to
    include:
         1.  Technology applications  that have been demonstrated and can be
            retrofitted on existing motor vehicles.
         2.  Technology for which there will be a production capacity avail-
            able to produce the estimated number of parts required soon
            enough to allow for distribution and installation prior to the
            effective date of the regulation.
         3.  Technology that is compatible with all safety regulations and
            takes into account operational considerations, including mainte-
            nance,  and other pollution control equipment.
         "Cost of compliance" means  the cost of identifying and carrying out
    the action that must be taken to meet  the specified noise emission level,
    including the additional cost of operation and maintenance.
    Discussion of the technology  and  cost required to achieve specified noise
emission levels must be based on an understanding of the  sources of motor
vehicle noise.  This section describes the noise characteristics of large

-------
n otor vehicles, the technology available, and the cost of achieving noise
reduction.  It specifically discusses multiaxle diesel trucks because (1) they
make the most noise, (2) most of the available data relate to these trucks,
and (3) any regulation which is feasible for such trucks will also be feasible
for other large vehicles.
    The noise produced by a truck depends on the type and the quality of its
component parts.  Large trucks are not standardized as are automobiles.
Specialized user needs result  in a greatly varied assembly of components,
especially with respect to power train and related equipment.  As a result,
truck noise can vary considerably from vehicle to vehicle. To illustrate the
extent of this variation, the discussion of noise sources below is preceded
by a brief description of truck components.
GENERAL CHARACTERISTICS OF LARGE TRUCKS
    Diesel engines may be naturally aspirated (air introduced at atmospheric
pressure), turbocharged, or supercharged by the engine itself.  The engine
can be located either at the front of the cab (in "conventional" trucks) or under
the cab (in "cab-over-engine" trucks).
     Exhaust pipes may be routed horizontally underneath the body of the
vehicle or vertically to the rear of the cab - commonly referred to as  a
"straight stack".  A straight stack is usually preferred, because it directs
exliaust fumes away from motorists and pedestrians.  Either single or dual
exliaust systems may be installed.  The engine intake may be situated  on or
under the hood in a conventional style truck or to the rear of the cab in either
the conventional or the cab-over-engine (COE) style.  If it is behind the cab,
it may be on the same or opposite side of the cab as the  exhaust system.
     The power-to-weight ratio for a  fully laden truck is significantly less
than that for an automobile, with the  result that the necessary torque must
be transmitted through a wide range of gears - up to as many as 15. The
torque  is usually applied to either one or two drive axles. The number of
 axles on the entire vehicle, including the trailer, can range from 2 to  11,  the
 limit varying according to state regulations.  In general, the greater the

-------
number of axles, the greater the load-carrying capacity of the truck.  Corre-
sponding in part to the number of axles, the number of tires on a heavy truck
trailer combination can range from 10 to 42.
    Figure 1 shows the effect of vehicle speed and engine rpm on engine
noise at 25 ft.  However, noise from the propulsion system is not the only
contributor to the overall noise level.  At speeds greater than about 45 mph,
additional noise of significant magnitude is produced by the interaction
between the tires and the road surface* '.  The relationship between pro-
pulsion system  noise and tire noise as a function of vehicle speed is shown
          f6 "7^
in Figure 2l * '.  The speed at which tire noise begins to dominate depends
primarily on the type and number of tires on the truck, the degree of tire
wear, tire load, type of pavement, and tire inflation pressure* '.
COMPONENT NOISE SOURCES AND QUIETING TECHNIQUES
    The total noise level produced by a truck is the logarithmic sum of the
individual noise levels produced by several different components. These
component noise sources, shown in Figure 3, are as follows (not necessarily
                      (9)
in order of Importance)   •
    •   Exhaust system
    •   Engine cooling fan
    •   Engine (mechanical)
    •   Air intake system
    •   Transmission  (gearbox, drive shaft, rear axles(s))
    •   Auxiliary engine equipment
    •   Tire/roadway  interaction
    ii   Aerodynamic flow
    n   Brakes
The first four sources are of major importance for the trucks of concern
here when they  are traveling at low speeds (less than 45 mph/  '.  As
Figure 2 shows, at higher speeds (greater than 45 mph),  tire noise assumes
a much greater significance.  A brief discussion of these major sources is
contained in the following sections.
                                      10

-------
100
         I   I   I  I
                           I       I
                      Maximum Engine Speed
I       I
 a.

o
01

 S

CO
   80
o
01


I
   70
   60
                             I       I
                                            I       I
         7  8  9  10          15     20

                      Vehicle Speed, mph
                                           30     40    50
                                                                     100
                                                                      90
                                                                  2
                                                                  oa
                                                                  •o
                                                                a
                                                                o
                                                                1
                                                                      80
                                                                      70
                                                                     60
                         1000
I       I
                                                                                         8 mph
                                     I	I
                 J	I
     2000       3000   4000


     Engine Rev./Mm.
                                    Microphone 7.5 Meters (25 Feet) From Centerline of Vehicle's Path
         Figure 1.  Propulsion System Noise Versus Vehicle Speed and Engine Speed

-------
  100 i
Tire Combinations
Steering Axle
o New Ribs
ii New Ribs
A New Ribs
Drive Axles
'/4 Worn X-Bars
New X-Bars
New Ribs
Trailer Axles
New Pocket Retread
New Rib Retread
New Rib Retread
   90
Engine Related Noise Alone
Thru 12 Gear Steps
o
in
10
•o
I
•2
i  80
•§
   70
   60
                   10
    20             30

      Vehicle Speed, mph
40
50
          Figure 2.  Propulsion System and Tire Noise for a
                     Typical 5 Axle Tractor Trailer (from
                     reference 6 and 7)
                                        12

-------
  B
  Major Noise Sources
A.  Engine (Mechanical)
B.  Engine Cooling Fan
C.  Engine Exhaust
D.  Air Intake System
         Other Sources
E.  Transmission
F.  Ancillary Equipment
G.  Tire/Roadway Interaction
H.  Aerodynamic Flow
I.   Brakes
 Conventional (C) Cab
               Cab-Over-Engine (COE)
       Figure 3.  Truck Noise Sources and Cab Types
                                 13

-------
KXIIAIIST SYSTKM
    L']xh;iust noise is created when engine exhaust gases cause oscillations
williin the exhaust pipe.  These oscillations are radiated to the atmosphere
at the tail pipe.  The noise is a function of engine type,  induction system,
exhaust system, and other associated parameters'  '.   In addition to being
radiated from the end of the tail pipe, exhaust noise is transmitted through
the exhaust pipe and mufflpr walls.   Noise is also produced by the ann'irn-
tion of engine brakes (on trucks so equipped), which assist the wheel brakes
by producing a retarding force on the engine.  Typical exhaust noise levels
range from 77 to 85 dB(A) at 50 ft, independent of vehicle  speed^   ', and
can be much higher in trucks which have been poorly maintained.
    Although the exhaust system is a major noise source, significant noise
level reductions can be achieved fairly easily.  A good muffler is mandatory,
and for  maximum quieting, a double-wall or wrapped muffler can be used to
reduce radiation through the walls.   Consideration can also be given to
wrapping the tail and exhaust pipes with insulation.  The system must be
free from leaks and should be attached by isolation  mounts to the truck frame.
The location of the muffler in the overall system, the exhaust pipe length,
and diameter, and the tail pipe length and diameter should be considered,
although these factors assume a gradually lessening importance as the
attenuation capability of the muffler increases. Muffler specifications and
suggested exhaust system configurations are currently offered by major
muffler manufacturers for almost every engine, although no universal
muffler exists which is the best for all types of engines.
    Exhaust noise alone from trucks equipped with  the best available mufflers
typically ranges from 72.5 to 80 dB(A) at 50 ft.  These mufflers provide
attenuation of from 9.5 to 27 dB and  are installed on some new trucks as
                  (12}
standard equipment  '.  A good quality muffler typically costs from $35
to $45,  and since the installation is simple,  many trucking companies do it
themselves.  Installation costs for either single or  dual systems are about
$15*  '       For maximum effect, it is necessary  to replace existing flexi-
ble exhaust pipes with rigid pipe and slip joints at a cost of about $45 per
side including labor.
                                  14

-------
COOLING FAN
    Trucks generally use axial fans to draw air through a front -mounted
radiator.  The air cools water which in turn cools the engine. Fan noise
is the result of air flow irregularities and is partially governed by the
proximity of shrouds, radiators, grills, and radiator shutters '  '.  The
noise produced by the fan is related to fan tip speed.  Most diesel engines
on heavy trucks reach maximum rated horsepower at about zLw rpm.  At
this speed,  the fan can be a major contributor to the overall truck noise
level.  Typical truck fans alone  exhibit noise levels in the range of 78 to 83
dB(A) at 50  ft at rated engine speed*16\
    Since noise from a cooling fan increases with the rotational speed,  it
is possible to reduce the noise while maintaining the same air flow (to
satisfy the same cooling requirement) by using a larger fan turning at a
slower speed.  In many cases this may require the installation of a larger
radiator, which could result in an expensive modification to the front of the
engine compartment.
    It is often possible to install a fan blade that produces less noise while
at the same time providing adequate cooling.  Most existing fans are stamped
out of metal with equal spacing between the blades, and they are driven at a
predetermined fixed ratio of fan-to-engine speed by a belt-driven pulley.
This type of fan was not originally designed to be quiet, nor is it particularly
efficient in performing its task.  In many cases, it can be replaced with a
more sophisticated design that affords a fan noise  (not total truck noise)
reduction of from 7 to 12 dB*  \ The cost is  in the range of $40 to $35
including installation1  '.  Overall truck noise can also be reduced by about
1 dB in some cases by incorporating a venturi-type shroud with a small tip
clearance, at a cost of about $45 including installation.
                                     15

-------
     Trucks arc designed to be able to cope with heat rejection at maximum
engine power with little or no ram air.  Since ram air increases with vehicle
speed, fans become less important at higher vehicle speeds and could be
slowed or stopped in many instances. The critical cooling requirement occurs
when the truck is moving slowly in a low gear but the engine is developing full
horsepower (e.g. when pulling a heavy load up a long grade). Trucks, un-
like automobiles, usually do not have an overheating problem when thp
vehicle is stopped and the engine idles at low rpm.  Given these character-
istics, it is possible for a truck to have a fan which does not operate
continuously.
     Fans are now available which operate only when additional engine cooling
is required and which idle when the cooling due to ram air  flow is sufficient.
A typical fan of this type has either a thermostatically controlled mechanical
clutch or a viscous fluid clutch. The viscous fluid clutch permits the fan to
rotate at reduced speeds and the thermostatically controlled mechanical
clutch permits the fan to stop completely when not needed.  Fans utilizing
these clutches are about 3 to 10 dB quieter than conventional fans*19).
    A viscous clutch costs about $240 including about $15 for the suggested
fan blade.  A thermostatically controlled mechanical clutch including the
necessary fittings costs from about $285 to $360, plus $40 to $50 for
installation*20' 21).
ENGINE  (MECHANICAL)
    Mechanical noise in internal combustion  engines is caused by the
combustion process, which produces the high gas pressures necessary to
force the piston down the cylinder and turn the crankshaft.  The rapid rise
in cylinder pressure immediately following combustion creates mechanical
vibrations in the engine structure which are transmitted through the cylinder
walls, oil pan, rocker arm, and covers. Some of this vibration is subse-
quently radiated into the atmosphere as acoustic energy.
                                16

-------
    Gasoline engines initiate combustion with a flame which spreads
smoothly throughout the cylinder until the fuel-air mixture is burned.
Diesel engines, however, rely on much higher compression ratios (about
17:1 rather than 9:1) to produce spontaneous combustion.  This causes a
more rapid change in pressure in the cylinder,  which in turn results in
increased engine vibration and hence higher noise levels than those
associated with gasoline  engines.  As a result,  the mechanical noise
levels of diesel engines often are as much as 10 dB higher than those of
gasoline engines ^2^.  The engine mechanical noise contribution in typical
                                                    /23\
diesel-powered trucks is on the order of 78 to 85 dB(A)v   '.
    Turbochargers are often used to increase the pressure of the intake
air.  This reduces the pressure fluctuations in the engine and, in turn,
                           (241
lowers the engine noise lever  '.  However, turbochargers may in some
cases whine, contributing to the overall noise level.
    Retrofit methods of reducing engine noise are generally one of two
kinds:
    1.  Modification of certain exterior surface covers.
    2.  Installation of acoustic absorption material and acoustic bar-
        riers in the engine enclosure.
Engine noise reduction kits suitable for a limited number  of engine models
are available from a few major engine manufacturers. These kits consist
of various acoustically treated panels and covers and provide a reduction
of about 3 dB in engine mechanical noise (as opposed to total vehicle noise
level) at a cost of $50 to  $100 for materials^  ^ and, typically, $30 for
installation^  ' . Such kits are in limited production at this time and have
not undergone complete durability testing v
AIR INDUCTION SYSTEM
    Induction system noise is created by the opening and closing of the
intake valves; this action causes the volume of air in the system to
pulsate.  The associated noise levels  depend upon the type of engine, the
engine operating conditions, and whether it is turbocharged or naturally
aspirated.  Typical intake noise levels alone vary from 70 to 80 dB(A)'   '.
                                17

-------
     The state of intake noise reduction technology is very similar to that
of exhaust noise reduction.  Major manufacturers are able to provide
assistance in proper selection of air intake systems for all popular engine
       (29)
models   '.  Retrofitting the intake systems of trucks in service consists
of replacing older air cleaners with modern quality, dry element air cleaners
at an aversige cost of from $100 to $130*   '.   Intake cleaners and silencers
are manufactured largely by the major muffler manufacturers.
TIRE/ROADWAY INTERACTION
     Truck tires for highway usage can be classified into two categories
- rib tires and  crossbar tires (also known as lug or cross rib tires).  Rib
tires look like automobile tires, with the tread elements oriented circum-
fcrentially around the tire.  This is the most common type of truck tire and
can be used in all wheel positions.  Rib tires are used almost exclusively on
steering axles because of their superior lateral traction and uniform wear
characteristics.  Crossbar designs have the tread elements oriented trans-
versely to the plane of the tire.  Many trucking companies prefer to use
crossbar tires  on drive axles, since they provide up to 60% greater initial
           (31.)
tread depth^  ', and hence greater mileage before recapping.
     The noise-generating mechanisms of tire/roadway interaction are not
completely understood.  It is known that the entrapment and release of air
from the tire tread cavities produces noise.  Also, it appears that the
vibration of the tire contributes to the total noise lever   '.   However, the
effect on noise  levels of the large lugs on crossbar tires and of the road
surface arc not well quantified.  The result is that basically all the noise
information available has been obtained experimentally, and tire manu-
facturers do not appear to be close to any major breakthrough that would
result in crossbar tire designs exhibiting significantly lower noise levels.
    There seem to be no conclusive data which indicate any significant
difference in traction properties between rib and crossbar tires under dry,
wet, or icy conditions   Any advantage in traction is probably in favor of
                                   18

-------
rib tires, becaube they normally provide about 59o more rubber in contact
with the road.  However, in snow, sand, gravel, mud,  or loose dirt,
where the tire does not come into contact with a firm surface,  some cross-
bars will give better traction than rib tires   .
     Extensive measurements of the noise level produced by tires mounted
on the drive axle of a truck-tractor have been conducted by the National
Bureau of Standards and the Department of Transportation'   ' (ccc Figure
4).  Typical values of the noise level measured at 50 ft are 68 and 73 dB(A)
at 3!> mph for new  rib and crossbar tires, respectively, on a concrete
roadway.  At 55 mph these levels typically increase to 75 and 83 dB(A)*  ',
respectively, although higher values are by no means uncommon.  In general,
rib tires produce lower noise levels than crossbar tires. The  noise produced
increases with tire wear, reaching a maximum value when the  tread is
approximately half worn. An increase  in noise level of 5 dB(A) over the
levels of new tires is not uncommon*  '.
    Data indicate that some retread tires having a tread composed, largely
of pockets which are not vented either around the tire or to the side produce
excessive noise levels by allowing air to be trapped, compressed, and
subsequently released as the pockets pass through the footprint area of the
tire.  These pocket retreads are responsible for noise levels around 95 dB(A)
at highway speeds  *  ''.
COST OF RETROFITTING INDIVIDUAL TRUCKS
    The noise control information given in the preceding section reflects
the state of available retrofit technology for each noise source.  To reduce
the noise level produced by an existing  vehicle, it is necessary to apply one
or more of the modifications outlined, depending upon the vehicle in question
and the overall noise reduction required.  For example, more  components
of an old, poorly maintained truck will  normally need to be modified than
those of one in new condition.  Also, more treatment will be required  for
trucks originally built with very noisy diesel engines.
                                 19

-------
             50
                   60
Speed, KM/Hr

 70     80
90
100
m
•o

1
c
o
VI
(TJ

-------
TECHNOLOGY ANL> COST REQUIRED TO COMPLY WITH A LOW-
SPEED STANDARD
    Treatments  indicative of what might be required to lower truck noise
(other than from tire/road interaction) to various levels and the associated
costs per treatment are listed in Table 4.  The noise levels are for low-
speed full-throttle acceleration measured according to SAE J366a on an
open site over a  hard surface. Since the noise levels of individual trucks
vary, not all trucks requiring treatment would require the treatments indi-
cated to meet each noise level.  The percentage of trucks in Table 4 that
need each type of component change were estimated by an EPA contractor
from data gathered by a company located in a regulated region of the
country which has been extensively engaged in retrofitting trucks to reduce
their noise.
    The estimated costs to achieve  90, 88 and 86 dB(A) are comparable to
the actual costs incurred by that company in retrofitting 7600 large multi-
axle trucks, which are shown in Table 5*   .  The 7600 trucks include
both gasoline and diesel-powered units, representing the proportion of
each type that required retrofit or repair to meet the noise limits.
    Very few trucks have actually been retrofitted to achieve a noise
level of 84  dB(A), since few State and local  jurisdictions have low speed
noise standards at levels below 86 dB(A). The EPA contractor estimated
a range of costs  of $292-462 to quiet the average multiaxle truck to 84
dB(A), while the retrofit service company estimated that it might cost
$950 to quiet a diesel multiaxle truck to that level. Costs should be some-
what lower for smaller medium and heavy duty trucks,  some of which
could be quieted  to 84 dB(A).
    There  is a practical limit as to what noise levels can be achieved on
all trucks through the use of retrofit technology.  EPA studies have indi-
cated that it is not cost-effective and often not feasible to  quiet in-service
motor vehicles much below the noise levels  that characterized them when new.
There are trucks in the existing fleet that contain diesel engines that are
                                  21

-------
                     TABLE 4
ESTIMATED COSTS TO RETROFIT TRUCKS TO VARIOUS NOISE
     LEVELS (According to SAE J366a) IN 1973 DOLLARS
Noise Level Typical Estimated Cost % Trucks Exceeding Avg. Cost Per
dB(A) @ 50' Treatment Per Item $ Specified Noise Level Truck Retrofitted
Requiring Component
Change


90 Exhaust1 50-100
100%
$50-$100
Total $50-$100


88 Exhaust 50-100
Fan2 35
100%
5%
50-100
2- 2
Total $52-$102



3
Exhaust 100
86 Fan4 80
Intake5 115
100%
10%
5%
100
8
6
Total $114




Exhaust6 100-200
Fan7 285-400
84 Intake5 115
Engine8 80-130
100%
50%
25%
25%
$100-$200
$143-$200V
$ 29-$ 29
$ 20-$ 33
Total $292-$462
1.
2.
3.

4.
5.
6.
7.

8.
Muffler and labor — single or dual system
Replaced fan blade


Mean cost for muffler and labor, plus additional cost
requiring replacement of flexible tubing, etc.
Replaced fan blade and added shroud in some
Average cost of dry element air cleaner with

cases
built-in
Muffler and replacement of feasible pipes — single or


for some trucks


silencer
dual system
Viscous fan clutch and new fan blade in conjunction with shroud.
Thermostatically controlled clutch
Partial engine kit plus installation.




                            22

-------
                          TABLE 5

   ACTUAL COSTS OF RETROFITTING 7600 TRUCKS TO ACHIEVE
                                                   /
      SPECIFIED NOISE LEVELS ACCORDING TO SAE J3G6al
Level                  90 dB(A)     88 dB(A)     86 dB(A)     84 dB(A)

Actual Cost (1973 $>      $45-100     $50-110      $50-205      _
Per Truck
                                 23

-------
too noisy to be sold in jurisdictions that enforce an 8<> dH(A) noise emission
standard at 50 feet.  These engines arc being phased out of new trucks,
but they represent an obstacle to limits lower than 8G d!3(A) for Interstate
Motor Carrier Regulations that must take best available technology and
cost of compliance into account.
     Many heavy trucks are custom-built, and it is technologically possible
to replace  engines or rebuild in-service trucks to achieve large reductions
in noise emissions.  However,  this is not considered to be within the
definition of "best available technology," and would involve very high
costs.  Even achieving 84 dB(A) for all trucks would require the extensive
use of engine enclosures that are not currently available and that have not
been adequately tested for safety and compatibility with engine maintenance
needs.
     EPA believes that a noise level of 86 dB(A),  measured according to
SAE J366a, is achievable through the use of best available technology by
almost all  medium and heavy duty trucks in the existing fleet.   It is also
achievable by buses,  since they use the same engines and tires as trucks.
Trucks are already being retrofitted to reach 86 dB(A) in a number of
states and  actual experience indicates that the associated costs were
$50-205 per truck in 1973 for those in-service trucks that had to be
retrofitted.
     Additionally, at least one major truck manufacturer has indicated its
intention to work with suppliers to develop a retrofit noise control package
to bring older trucks  into compliance with noise levels already proposed.
This should help provide the retrofit service  capability that will be needed
to enable vehicles to comply with the Interstate Motor Carrier Regulations.
    Table 4 indicates that most trucks currently  exceeding 8G dB(A)
require only a muffler to be in compliance, and muffler manufacturers
have testified in public hearings that adequate mufflers can be available
in sufficient numbers to permit compliance of all trucks within one year
of promulgation of the Interstate Motor Carrier Regulations.
                                  24

-------
TECHNOLOGY AND COST HKQUIHKI) TO COMPLY WITH A IIIGII-SIM-.'KD
STANDAIID
    Since engine-related noise does not increase at high speed above the levels
associated with low speed maximum acceleration, the high speed standard
should exceed the low speed standard only by the noise differential associated
with the increase in tire noise at higher speeds.  Figure 4 indicated that tire
noise continues to increase as truck speed increases.
    Considerable high speed noise reductions can be obtained through the
replacement of "pocket retread" tires by crossbar tires at no increase in cost
or loss of performance. However, crossbar tires begin to dominate overall
truck noise levels at speeds in excess of 45 mph and a high speed standard of
86 dB(A) might require the elimination of virtually all crossbar tires.
    It appears that per-mile cost differentials between  tires having different
types of tread may depend on tire composition and terrain as well as on motor
carrier recapping policies. A comprehensive study of cost-differentials
associated with the use of truck tires of different types  is being carried out by
EPA as preparation for possible future tire regulations and/or revisions of the
Interstate Motor Carrier Regulations.
    However, due to performance and safety requirements it does not appear
feasible or desirable to require the elimination of all crossbar tires at this
time.  It may  be desirable to further restrict  the use of noisy crossbar tires
in the future,  but such an action requires more data on  cost, performance,
and safety differentials between tires of different treads than currently is
available.
    Accordingly, a four decibel margin has been added to the 86 dB(A) low
speed standard to take tire noise into account.  Actual experience indicates
that this will require the elimination of some crossbar tires on heavy trucks
that have a very large number of axles.  However, it should still be possible
for these trucks to operate with crossbar tires on the drive axles.
    A comparison of the results of surveys  of actual truck noise levels (data
from the surveys is presented in section 4), indicates that essentially the
same percentages of trucks exceeded 86 dB(A) under low speed acceleration
                                  25

-------
as exceeded 90 dB(A) under high speed conditions, and also tiiat the per-
centages are very nearly the same for each MVMA class of trucks considered
separately by number of axles.  This strongly suggests that the two standards
are comparable.
    For those trucks that must change from crossbar tires to rib tires in
order to comply with the standards, a small cost penalty may result.  Under
a strategy of recapping each tire only  once, the cost difference between
crossbar and rib tires is approximately $. 23 per thousand miles.  For a
single drive axle truck,  this represents a cost difference of less than $.001
per mile.
    A high-speed noise  level of 88 dB(A) would be achievable by two-axle
trucks because they have fewer tires than multiaxle trucks.  A separate
standard was considered for this category, but an analysis of highway noise
levels performed using a DOT Highway Noise Prediction Model indicated that
reducing the noise emissions of a portion of the truck fleet over 10,000 pounds
by two decibels would have no measurable effect on highway noise levels.
Accordingly, one high-speed noise limit seemed reasonable for all motor
vehicles over 10,000 pounds GVWR operated by motor carriers engaged in
interstate commerce.
                                 26

-------
                                Section :J

             INTERSTATE MOTOR CARRIER REGULATIONS

    This section contains a summary of the regulations, a short explanation
of Hie changes made in the regulations since the notice of proposed rule-
making, and an analysis of the relationship between the various test measure-
ment procedures used to ascertain compliance of motor vehicles with noise
emission standards.
SUMMARY OF THE REGULATIONS
    The Interstate Motor Carrier Noise Emission Standards are applicable to
all motor vehicles above 10,000 Ib GVWR/GCWR operated by motor carriers
engaged in  interstate commerce.  There are two interrelated standards directed
to the way in which the motor vehicles arc operated while in use.  The first is
a requirement that motor vehicles generate no more than 86 dB(A) at  50 feet in
speed aonos at or under 35 mph under all conditions.  The second  is that the
vehicles generate no more than 90 dB(A) at 50 feet in speed zones  over 35 mph
under all conditions.  The intent of these two standards is to limit maximum
propulsion  system noise to the same level in both speed zones, but to provide
an additional margin for tire noise in the high speed zones.
    If the actual vehicle speed (rather than the posted speed limit) were used
in the regulation, then enforcement would require the simultaneous measure-
ment of each vehicle's speed and noise level.  This would be quite difficult in
the case of a truck operating in a  stream of faster-moving passenger  car
traffic.  To remove this obstacle to enforcement, the standards are keyed to
the speed zone in which the vehicle is operating rather than its actual speed.
This is the rationale for setting the low-speed, high-speed break at 35 mph
rather than 45 mph, where tire noise could begin to be important.
    A stationary engine run-up test standard of 88 dB(A) has been included in
order to permit enforcement at roadside weighing stations.  This test will
                                    27

-------
typically be performed over a hard site and is applicable only to vehicles with
engine speed governors.  The test is inappropriate for vehicles without
governors because of the following:
    a.   Wide variability is introduced by operator technique and tachometer
         errors in accelerating to maximum rated rpm in tests of ungoverned
         engines.
    b.   Wide variability exists in the maximum rated rpm for ungoverned
         engines, and maximum rpm in a stationary i-un-up test may be far
         nhovc maximum rpm of the engine when in operation.
    c.   The possibility of catastrophic failure exists when an ungoverned
         engine is accelerated rapidly to maximum speed when not under load.
    Most vehicles will violate the regulations only when their exhaust  systems
are faulty, and a visual exhaust system inspection standard has been included
to cover this possibility.
    A visual tire inspection standard has also been included to provide an
effective means of eliminating the noisiest type of tire treat pattern, except
in cases where it can be shown that the vehicle can meet the 90 dB(A) standard
even when using tires whose tread appears to be noisy.
    The effective date of the regulations is one year from  the date of promul-
gation.  EPA has determined that the required retrofit components will be
available within this period and that a one year effective date will not impose
an undue hardship on the trucking industry.
REVISION OF THE PROPOSED REGULATIONS PRIOR TO PROMULGATION
    The Interstate Motor Carrier Noise Emission Regulations which are now
being promulgated incorporate several changes from the proposed regulations
which were published on July 27,  1973.  These changes are based upon the
public comments  received and upon the continuing study of motor carrier noise
by the Agency. In all but one instance such changes are not substantial; they
are only intended to further clarify the intent of the proposed regulations.
                                    28

-------
     The sole substantive change is the deletion of proposed Section 202.12,
"Standards for Level Street Operations 35 MPH or Under."  This section was
originally proposed as it was felt that vehicles which could comply with a stan-
dard of 86 dB(A) under any conditions on highways with speed limits of 35  mph
or less could be driven so as to comply with a standard of 80 dB(A) when operated
at constant speed on level streets with speed limits of 35  mph or less.  It was
the intent of the Agency through this section to thereby regulate the manner of
operation of the vehicle, by the driver, without imposing any additional noise
reduction requirement to the vehicle proper beyond that needed to meet the
86 dB(A) standard.  Substantial questions were raised regarding the validity of
the data upon which the standard was based.  The Agency, upon review of the
relevant data,  agrees with the comments and accordingly, the Standards for
Level Street Operations section has been deleted.
     Those changes made to clarify the intent of the regulations, and the reasons
therefore,  are as follows:
Section 202.10 - Definitions
     "Common carrier by motor vehicle, " "contract carrier by motor vehicle, "
and "private carrier of property by motor vehicle" were deleted.  In their place,
the definition of "motor carrier" was expanded to incorporate, by reference,
the definition of those terms in paragraphs 14, 15, and  17, of Section 203 (a) of
the Interstate Commerce Act (49 USC 303 A).  This treatment more closely
follows Section 18(d) of the Noise Control Act and thereby insures that any
question as to the definition of those terms will be resolved by reference to the
body of law which Congress intended to apply to Section 18.
    The definitions of "dB(A),""sound pressure level, "and "sound level," were
changed slighty to be consistent with the definitions of those terms used in the
document "Information on Levels of Environmental Noise Requisite to Protect
Public Health and Welfare with an Adequate Margin of Safety," issued by the
Environmental Protection Agency in March 1974.  "Fast meter response" has
been expanded for clarity.
                                    29

-------
     "Gross combination weight rating" (GCWR) has been added to avoid any
possible confusion over whether the regulation is applicable to combination
trucks (i. e., tractor-trailer rigs) over 10,000 pounds weight rating.  The
provisions of Subpart B of the regulation are applicable to all single and com-
bination vehicles over 10,000 pounds GVWR or GCWR operated by interstate
motor carriers.
     "Interstate commerce" has been modified to insure that any questions
as to its scope would be resolved by reference to Section 203(a) of the Inter-
state Commerce Act, consistent with the reference to that. Act in Section 18(d)
of the Noise Control Act.
     "Person" has been deleted, since (as discussed below) that word is no
longer used in Subpart B of the regulations.
     "Street," and "official traffic device," have been deleted,  since pro-
posed Section 202.12 in which they were used has been deleted.
     "Muffler" has been added to simplify the language of proposed Section
202.14, "Visual Exhaust System Inspection. "
     "Open site" has been added to further clarify the standards.
Section 202.11  - Effective  Date
    An effective date of October 1, 1974 was originally proposed for the
regulations.  The intent of the Agency in the Notice of Proposed Rulemaking
was that the proposed regulations would become effective one year from the
date of promulgation.  This intent is retained in this new section.
Section 202.12  - Applicability
    "Applicability" was moved to Subpart A of the final regulations as it is
appropriately considered a "general provision" of the regulations.  It has
been modified to clarify the intent of the Agency that the standards do not
apply to noise emission from warning devices or auxiliary equipment mounted
on motor vehicles; and that compliance with any provision of Subpart B does
not excuse any motor vehicle from compliance with the other provisions of
Subpart B.
                                   30

-------
Subpart B - Interstate Motor Carrier Operations
    The language used in Subpart B has been changed from, "no person shall
operate," to "no motor carrier subject to these regulations shall operate...;"
and the language in section 202.20 was modified slightly to conform to this
change.  This change is intended to reflect more accurately the intent of Congress
and these regulations, that they  are to establish uniform national noise emission
regulations for those operations of interstate motor carriers which require such
treatment.  The revised  language clearly imposes sole responsibility for meeting
the requirements upon the motor carriers which own and operate the subject
motor vehicles. The proposed language,  using the broad term "person," would
have imposed that responsibility upon the drivers of subject motor vehicles as
well as the companies which operate them.  "Motor carrier," as defined in
these regulations, includes independent truckers who both own and drive their
own vehicles.   The phrase "on an open site over any surface," was added to the
standards of Subpart B to further clarify the standards.
Section 202.21 - Standard for Operation Under Stationary Test
    The language of this section has been modified to further clarify that it
applies only to vehicles which have an engine speed governor.  Application of
a stationary run-up test to vehicles which are not equipped with engine speed
limiting devices could result in engine damage.
Section 202.22 - Visual Exhaust System Inspection
    The intent of the Agency in requiring motor vehicles subject to this
regulation to be equipped with exhaust system noise dissipative devices has
been further clarified through modification of the language  of proposed Section
202.14.  In addition, the exception to the proposed requirement relating to
vehicles with gas driven  turbochargers and equipped with engine brakes, which
were  demonstrated to meet the other standards of Subpart B, has been deleted.
Such equipment is included in the term "other noise dissipative device," and
therefore need not be treated separately.
                                   31

-------
Section 202. 23 - Visual Tire Inspection
    The intent of the Agency was to specifically preclude the use of "pocket
retread" tires which when new are demonstrably noisier without having any
accompanying benefit in safety or cost over other types of tires.  The pro-
posed Section 202.15 has been modified in response to comments by tire
manufacturers that the regulation as proposed could have covered some types
of tires which are not in fact exceptionally noisy.
Proposed  Section 202.16 - Enforcement Procedures
    This proposed section has been deleted.  As the Noise Control Act
places enforcement responsibilities for these regulations with the Department
of Transportation, the section as proposed added nothing not specified in the
Act.
Proposed  Subpart C - Special Local Conditions Determinations
    The procedures for applying for determinations as called for in Section
18(c)(2) of the Act, will be published by EPA as "procedures" and not as part
of this regulation. Accordingly, Subpart C has been deleted.
Preemption
    Under Subsection 18(c)(l) of the Noise Control Act, after the effective date
of these regulations no State or political subdivision thereof may adopt or enforce
any standard applicable to noise emissions resulting from the operation of motor
vehicles over 10,000 pounds GVWR or GCWR by motor carriers engaged in inter-
state commerce unless such standard is identical to the standard prescribed by
these regulations. Subsection 18(c)(2), however, provides that this section does
not diminish or enhance the rights of any State or political subdivision thereof
to establish and enforce standards or controls on levels of environmental noise,
or to control, license, regulate, or restrict  the use,  operation or movement of
any product if the Administrator, after consultation with the Secretary of Trans-
portation, determines that such standard, control, license, regulation, or restric-
tion is necessitated by special local conditions and is not in conflict with regula-
tions promulgated under Section 18.
                                   32

-------
     Conversely,  Subsection 18(c)(l) does not in any way preempt State or
 local standards applicable to noise emissions resulting from any operation
 of interstate motor carriers which is not covered by Federal regulations.
 Thus, under the proposed regulations States and localities will remain free
 to enact and enforce noise regulations on motor carrier operations other than
 their operation of motor vehicles over 10,000 pounds GVWR or GCWR, with-
 out any special determination by the Administrator.  Only after a Federal
 regulation on noise emissions resulting from a particular interstate motor
 carrier operation has become effective must the States and localities obtain
 a special determination by the Administrator under Subsection 18(c)(2), in
 order to adopt or enforce their own use restrictions or environmental noise
 limits on that operation.
     Some interstate motor carrier operations on which no Federal noise
 standards or regulations have become effective,  and which may, therefore,
 be subjected to State and local noise standards without any special determina-
 tion by the Administrator, may indirectly include motor vehicles which are
 covered by preemptive Federal regulations.  Motor carrier maintenance shops,
 for example, may from time to time emit the noise of trucks undergoing tests
 along with noises common to many industrial operations such as forging and
 grinding; and motor carrier terminals and parking areas include trucks among
 their many types of noise sources.
     In most instances, compliance with State or local standards on non-
 Federally regulated operations of motor carriers is achievable without affecting
 the Federally regulated motor vehicles within them.  Standards on noise
 emissions from repair shops, for example, can be met by such measures as
 improved sound insulation in the walls of the shop, buffer zones of land between
 the shop and noise-impacted areas,  and scheduling the operation of the shop to
 reduce noise at those times of the day when its impact is most severe.  Standards
 on motor carrier terminals and parking areas can be met by a variety of steps,
including reducing the volume of loudspeaker systems by using a distributed sound
 system or replacing speakers with two-way radios, reducing noise emissions
from equipment which is not covered by Federal regulations, installing noise
                                   33

-------
hurriors :iround noisy equipment, :icc|iiirmu :i»ldilion;iJ hind lo :ict as :i noise
huffcr, mid locating noisy equipment such ns p:irked trucks with operating
refrigeration equipment as far us possible from adjacent noise-sensitive property.
State or local regulations on noise emissions from motor carrier operations  which
the motor carrier can reasonably meet by initiating measures such as these  are
not standards applicable  to noise emissions resulting from the operation of motor
vehicles over 10,000 pounds GVWR or GCWR, and thus would not be preempted by
the proposed regulations.  No special determination by the Administrator under
Subsection 18(c)(2) would be necessary.  State or local noise standards on opera-
tions involved in interstate commerce such as motor carrier terminals are,  of
course, subject to Constitutional prohibition if they are so  stringent as to place an
undue burden on interstate commerce.
    In some cases, however,  a  State or  local noise regulation which is not stilted
as ;i regulation applicable to a Federally regulated operation may be such a regu-
lation in effect, if the only way the regulation could be met would be to modify the
equipment which meets the Federal regulation applicable to it.  This would be the
case, for example, if after the proposed regulations become effective, a State  or
locality attempted to adopt or  enforce a limit on noise emissions from motor
carrier terminals in urban areas which could not reasonably be met by measures
such as noise barriers or relocating the  motor vehicles to  which this regulation
is applicable.  Such regulation would,  in effect, require modifications to motor
vehicles even though they met the Federal regulations and would thus be a regu-
lation applicable to them which would be  preempted under Subsection 18(c)(l).  It
could not stand if it differed from the Federal regulations,  unless the Administrator
made the determinations specified in Subsection 18(c)(2).  The same would be true
of any State or local standard  on motor carrier operations  which could not reasonably
be met except by modifying motor vehicles which comply with the proposed Federal
standards.
    State and local regulations on motor carrier operations which are not directed
at the control of noise, or which include  noise control as only one of many purposes
such as safety, traffic control, and the like, are not preempted by Subsection 18(c)(l)
of the Noise Control Act  and require no special determination under Subsection 18{c)(2)
                                    34

-------
 to be adopted or enforced.  Thus, the designation of some streets as truck routes,
 and prohibition of trucks from other streets, by State or local governments, are
 valid without any special determination under Subsection 18(c)(2).
 Auxiliary Equipment Considerations
     Some types of auxiliary equipment used in vehicles  operated by interstate motor
 carriers are necessary for the comfort or safety of passengers, or for the preser-
 vation of cargo.  Principal examples of such auxiliary equipment are refrigeration
 or  air conditioning units and concrete mixer bodies and  drives.   The auxiliary equip-
 ment noise emissions for these two types of vehicles, in particular, are at a level
 far enough below other significant components of vehicle noise,  as EPA's data
 indicate, to be masked by other noise sources during normal vehicle highway
 operations.
     Other auxiliary equipment, however, normally operates only when the trans-
 porting vehicle is stationary or moving at a very slow speed, normally less than 5
 mph.  Examples  of such equipment  include cranes,  asphalt spreaders, ditch diggers,
 liquid or slurry pumps, air compressors, welders, and trash compactors.  The
 operation of such equipment is not intended to be covered by these regulations.
 Emergency Equipment and  Vehicles
     because of the emergency or safety aspects of their operation the regulations
 arc not applicable to vehicles such as fire engines,  ambulances, police vans,  and
 rescue vans when responding to emergency calls.   Similarly, these regulations
 are not intended to apply to snow plow operations.
 Enforcement Procedures, Violations, and Penalties
    Enforcement procedures are to be developed and promulgated under separate
 rule making by the Department  of Transportation.  Such enforcement procedures
 will specify minimum requirements for instrumentation, test sites,  and other
 conditions necessary to  insure uniformity in testing and a minimum level of
 precision.
    Enforcement of the  standards is contemplated to be more efficient under
 some conditions if measurements are permitted to be made at distances other
than 50 feet under procedures that provide for equivalency to the standards
measured at 50 feet.
                                   35

-------
    Section 10 of the Act specifies that any violation of these and any future
regulations established under the authority of section 18 of the Act constitutes
a prohibited act.  Any person who willfully or knowingly violates the regulation
shall be punished by a fine of not more than $25,000.00 per day of violation or
imprisonment for not more than one year, or by both, or  a fine not exceeding
$50,000.00 per day of violation, or imprisonment for not  more than two years
or by both, following a conviction for a previous violation of the Noise  Control
Act.
RELATIONSHIP BETWEEN LOW-SPEED MEASUREMENT PROCEDURES
    During the Public Hearings on Noise Abatement and Control held in San
Francisco in September 1971,  testimony was offered to show the variations in
noise level of a truck as measured under maximum acceleration low-speed
conditions at nine different sites.  Compared to a hard surface open site, grass-
covered sites produced noise levels that were 1.5 to 2.0 dB(A) lower,  while the
presence of near-by buildings produced noise levels 1.5 to 2.0 dB(A) higher.
This implies that a truck in compliance with a standard as measured over a
soft surface could be out of compliance as measured over a hard surface unless
suitable correction factors are applied.
    In actual practice, highway measurement and enforcement of the noise emis-
sion standards contained in these regulations will occur on sites having surfaces
that range from hard to soft.  Motor vehicles  covered by the regulations should
have no trouble being retrofitted to comply with an 86 dBA standard as measured
at a typical roadsite site.
    This same rationale has been used to set  the level of  88 dB(A) for  the Sta-
tionary Run-up Test Standard.   The stationary run-up test (SRUT) is a means
of determining maximum propulsion system noise.  A vehicle  propulsion system
which emits a given sound power by this test will typically emit that same value
in use when power requirements are maximum due to conditions of load,  accelera-
tion, and grade when measurement site parameters are comparable.
    The stationary standard at 88 dB(A) is approximately  equivalent to the  low
speed standard at 86 dB(A) because of the different measurement sites  used.
Both levels would be the same  if both were to be implemented  on pavement, or
                                   36

-------
both on grassy sites.  This level would also be the same if the J366 maximum
noise test were included in the standards.  In a tabular form the relationship
between the three test methods is as follows:
                   Stationary         Max-Noise Low
                     Runup            Speed Passby         J36G
      Hard Site         88                 88                 88
      Soft Site          86                 86                 86

    SHUT was developed because the Society of Automotive Engineers J3(iGa
tost, which is almost universally performed by vehicle manufacturers, their
customers, and their suppliers,  is wholly unsuitable for use in roadside
enforcement of a motor carrier regulation because of its technical require-
ments.
    In order  to obtain information on the  feasibility of using SHUT as an
enforcement test procedure, tests were performed at the International Harvester
Company Truck Engineering Center at the request of EPA. Although the data
collected do not represent a sample large enough to have statistical significance,
the experiment is indicative of what relationship can be  expected between SAE
J36Ga, SRUT, and Maximum Acceleration Passby results as measured over a
hard surface.  The data are presented in  Figures 5,  6,  and 7 and Table 5.
                                37

-------
         90
     dBA
CO
00
         80
         70
                                                                      90
                                        .3 dBA
                                                                  dBA
                                                                      80
                                                                      70
                                                                                        86.8 dBA
                I    I    I     I     I
                                SECONDS
              I    I    I     I     I     I
                    SECONDS
                           J366a:  TRACTOR ONLY
                                                                              STATIONARY RUNUP TEST
 Figure 5.  Noise Level of a Large Diesel Truck as it
           Approaches and Passes a Microphone in
           the J366a Test.
Figure 6.  Noise Level of the Same Truck as
          it Idles, Followed by Engine Accel-
          eration to Maximum Governed rpm
          in the Stationary Run-up Test.

-------
05
CD
            90
            80
       dBA
            70
            60
                                                    •86.3 dBA
                                                                             I	I	i	I
                                                         SECONDS
                                MAXIMUM ACCELERATION TEST: TRACTOR PLUS TRAILER (GCW = 72,600 Ib)
j	I
        Figure 7.  Noise Level from the Same Tractor while Pulling a Load as it Accelerates Past a Microphone
                  in a Pass-by Test.

-------
                               Table 5
   MEASURED VALUES OF NOISE LEVEL IN dB(A) OF SEVERAL TESTS
                ON TWO DIFFERENT TYPES OF TRUCKS.
 PASSBY MICROPHONE LOCATIONS ARE ALL 50 FT FROM THE LINE OF
           TRAVEL, EACH 50 FT SUCCESSIVELY FARTHER
                     FROM THE START POSITION.

                        72,600 LB DIESEL           56,000 LB DIESEL
       TEST             CAB-OVER-ENGINE         CONVENTIONAL CAB
      	          LEFTSIDE  RIGHTSIDE      LEFTSIDE RIGHTSIDE
J366a (Tractor only)       86.4 dB(A) 86. 3 dB(A)        87.3 dB(A) 87.0 dB(A)
SRUT                    86.4      86.8             87.0       89.2
Acceleration Passby
    Location #1           87.0      86.3             87.5       88.0
    Location #2           86.3      87.0             85.9       87.5
    Location #3           85.4      85.8             86.3       88.0
    Location #4           86.0      86.8             85.5       87.2

    Two large dies el trucks were used for the tests, and in performing these
tests all measurement  conditions were identical: paved surface,  microphone
located 4 ft high, 50 ft  from the source.   The same series of tests, if performed
at a different site, would be expected to produce results differing in proportion
to the acoustic reflectivity of the surface between microphone and test vehicle
and due to normal variations in the tests themselves which render them less
than exactly repeatable.
    This example shows essentially the same maximum noise level for all tests.
However,  identical results are not always achievable under such comparisons;
the statistical correlation between J366a and SRUT is discussed below. Maximum
noise measured during acceleration will vary to some extent as a result of the
chance location of the microphone in relation to the maximum noise point in the
vehicle gearshift cycle.
                                 40

-------
77   78  79  80   81  82   83   84   85
   92


   91


   90


 •  89

87-
    J-366a
     dB(A)
                                                90  91   92   93
                         ~94   9598   97~
                                          87


                                          86


                                          85


                                          84


                                          83


                                          82
                                                Correlation Between
                                          81  J 366a & Stationary Test
                                          80
                                          79 52.
                                            Sea
                                            a"0
                                          78 :=
    Figure 8. Plot of Test Results According to SRUT and SAE J366a for 877
            Trucks.

-------
STATIONARY RUN-UP TEST CORRELATION WITH SAE J366a
    A very substantial data base has recently become available that relates the
measurements of truck noise taken using the SAE J366a maximum acceleration
pass-by test and the stationary Runup Test (SHUT). The data has been collected and
compiled by the Society of Automotive Engineers from several industrial sources.
    The stationary run-up test consists of measuring the maximum A-weighted
sound level at a distance of 50 feet from the vehicle engine exhaust during
maximum acceleration of the engine from low idle to high idle. The test is
conducted with the transmission in neutral and the clutch engaged.  The inertial
load of the engine during rapid engine speed acceleration makes an external
load on the engine unnecessary.  SRUT site and sound measurement instrumen-
tation requirements are similar to the SAE - J366a requirements.  Most truck
weigh stations can meet these site requirements.
    The stationary run-up test will be quite useful for enforcement at State
inspection stations and weigh stations.  A fleet owner may also use the test
to check his vehicle for compliance.  The correlation of the stationary run-up
test with SAE-J366a is very good.  Over 800 different trucks with governed
engines have been tested per SAE-J366a and per the stationary run-up test
procedure.  The results of these tests are plotted in Figure 8. To better
understand the meaning of the data points in Figure 8,  a statistical analysis
of this information is  presented in Figure 9.
    The analysis shows that given comparable site conditions the SAE J366a
test yields noise level measurements that are about 0.5 decibels higher on the
average for a given truck  than the stationary run-up test measurements.  The
standard deviation of the difference between the two measurements was 1.4 dB(A)
for the trucks in the sample.  This means that for 95% of the 877 trucks tested,
the stationary run-up  test measurement did not exceed the SAE J366a measure-
ment by more than 2 dB(A).
     The correlation coefficient for the two sets of test results was computed
for a sub-sample of 210 of these trucks, and was found to be 0. 71 (where 1. 0
represents perfect correlation).  The fact that the correlation was so high indi-
cates that a stationary run-up test can be used as a good approximation to a low
speed acceleration test.
                                   42

-------
   70
   60
   50
£  40

u

01

-------
                               Section 4

           NOISE MEASUREMENT OF IN-SERVICE VEHICLES

     This section presents the results and implications of a number of surveys
 of the noise produced by motor vehicles of different kinds, measured at different
 speeds and conditions according to several standard test procedures.
     Light trucks - those with a gross vehicle weight rating (GVWR) of 10,000 Ib.
 or less - typically produce peak passby noise levels of 64 to 72 dB(A) at 35 mph
 when measured at 50 ft.  These noise levels are about the same as those pro-
 duced by passenger cars at the same speed (40).  This result is not surprising,
 s ince the major noise-producing components of light trucks are very similar to
 those of automobiles:  both are powered by similar gasoline engines, both have
 two-axle chassis, and both usually use similar rib-type tires.
     Heavy and Medium Duty Vehicles (those with a GVWR or  gross combination
weight rating (GCWR) of more than 10,000 Ib.) can produce peak passby noise
 levels of 95  dB(A) or more at 50 ft.  (41).
     Although all vehicles contribute to the noise emitted along streets and high-
ways (which determines the ambient noise level in most urban communities (42)),
 Heavy and Medium Duty trucks cause a noise problem that can be separated from
the problem of motor vehicle noise in general.  Heavy trucks emit noise levels
that  are so much higher than those of other motor vehicles that they stand out
very noticeably.  Noise peaks of 12 dB above the ambient noise level from other
traffic arc commonly observed when a heavy truck passes by  (43).
 MEASUREMENT METHODOLOGY
     Noise is measured by determining (by means of a sound level meter) the
magnitude of pressure variations of various frequencies in the air.  Since a
person's subjective estimate of the magnitude of a sound is dependent upon the
relative magnitude of its component frequencies,  a weighting network is usually
employed to  match the response of the sound level meter to that of the human
                                   44

-------
ear (44).  The most commonly used network is the A-weighting network, which
is contained in all sound level meters.  Noise levels measured on the A-weighted
noise scale are recorded using the notation dB(A).  Noise scales other than A, B,
and C are available,  but they require a more complex analysis procedure, which
is normally not justified by improved correlation with human assessment (45).
Because noise levels can peak rapidly as a truck passes by, the sound level meter
is usually set to "fast" response.
    It has been argued that the A-weighted sound level discriminates against
low frequencies and, consequently,  should be replaced by the C-weighted sound
level in motor carrier noise standards.   However, the ear also discriminates
against  low frequencies so that at low frequencies the  sound pressure level must
be comparatively high before it can even  be heard. This may explain why the
correlations between A-weighted sound level and human  response are consistently
better than that obtained with the C-weighted sound level.
    A-weighting has been shown to be a fairly good and consistent indicator of
loudness for a variety of common noises  (46, 47).  On the other hand,  the C-
weighted level is consistently and significantly poorer than the A-weighted level
(48).  Insofar as a predictor for speech interference for a variety of noises, the
C-weighted level is very poor as compared to A-weighted level (49).  It may be
concluded from the literature that of all standardized weightings, the A-weighted
sound level has been the most successful of these measures as an indicator of
human response.  Some improvements could probably be gained by the new
weighting characteristics that have been suggested recently (N,  D,  Dl, and D2);
however, these have not been nationally or internationally agreed upon; thus, no
standardized  procedures or equipment exist for them at the present time.
    Noise levels decrease with distance from the noise source, so it is important
to specify the distance at which measurements are to be made.  For measuring
truck noise, the most usual measurement distance selected is 50 ft.  At closer
distances,  slight variations in measurement distance can produce significant
errors in the measured  noise level (50); at greater distances, background noise
levels and the presence  of noise-reflecting surfaces can pose problems in site
selection (51).
                                   45

-------
    In the surveys presented in this section, an effort was made to maintain
standard conditions at almost all sites.  Suitable instrumentation was used;
sound level meters met the requirements of ANSI SI. 4-1971, American
National Standard Specification for Sound Level Meters.  Microphone calibra-
tion was performed by an appropriate procedure and at prescribed intervals.
An anemometer was used to determine wind velocity, and microphones were
equipped with suitable wind screens.
    Restrictions were made to prevent measurements during unfavorable
weather conditions (e.g., wind and precipitation).   The standard site for pass-
by measurements was an open space free of sound reflecting objects  such as
barriers, walls, hills, parked vehicles, and signs.  The nearest reflector to
the microphone or vehicle was more than 80 feet away.  The road surface was
paved, and the ground between the roadside and the microphone was  covered by
short grass in most cases.
    The standard site for the stationary runup test included space  requirements
that were the same as for pass-by measurements, and the surface between the
microphone and vehicle was paved.  Microphones for stationary and  pass-by
measurements were located 50 feet from the centerline of the vehicle or lane
of travel, 4 feet off the ground,  and oriented as per manufacturer's instructions.
Variations from the standard measurement sites and microphone locations were
allowed if the measurements were suitably adjusted to be  equivalent  to measure-
ments made via the standard methods.  Exact procedures  for the tests are included
in the appendix.
SURVEYS OF TRUCK NOISE
    Truck noise surveys have been conducted in California in 1965 (52),  and 1971
(53), in the State of Washington in 1972 (54),  and in New Jersey in  1972 (55).  In
1973, EPA contractors conducted additional truck noise surveys of 6,875 trucks
operating at speeds over 35 MPH  in the states of California,  Colorado, Illinois,
Kentucky, Maryland, New Jersey, New York, Pennsylvania, and Texas, and  of
2,583 trucks operating under acceleration conditions at speeds under 35  MPH
in the states of California,  Colorado, Florida, Maryland, Missouri,  Texas,
and Virginia.
                                  46

-------
    In almost all cases, measurements were made at a distance of 50 ft from
the center of the first (outer) lane of travel, using A-weighting and fast response
on the sound level meter.  In the 1973 surveys, the type of truck and number of
axles were recorded in order to permit detailed analyses of the noise level dis-
tributions for various types of trucks.
    In addition,  a study of noise levels of 60 trucks produced during a stationary
run-up test was carried out by EPA in Virginia in February,  1974.
ANALYSES OF HIGH SPEED (OVER 35 MPH) SURVEY DATA
    Figure 10 shows cumulative probability distributions for the peak passby
noise levels measured at  50 ft under high-speed freeway conditions in the surveys
conducted prior to 1973.  The data shown are for  heavy trucks:  5,838 diesel trucks
in California in 1965 (56), 172 combination trucks in California  in 1971 (57),  531
trucks with 3 or  more axles in Washington in 1972 (58), and 1,000 trucks with 3
or more axles in New Jersey in 1972 (59).  The data are in close agreement: typi-
cally, 50% of the trucks were observed to exceed  87 to 88  dB(A) and 20% were
observed to exceed 90 dB(A).
    Figure 11 shows that under high-speed freeway conditions,  buses are about
2 dB quieter than heavy trucks.  Approximately 50% exceed 85 dB(A), and 6%
exceed 90 dB(A).  These data were obtained in New Jersey in 1973.
    Table 6 shows the mean noise levels and percentages  of all trucks with six
or more wheels that were observed to exceed 90.0 dB(A) under  high-speed free-
way conditions in ten states. These data were all obtained in 1973, except for
the Washington state data, which were obtained in 1972. The arithmetic mean
of the percentage of trucks exceeding 90.0 dB(A)  is 23.1%.  When the data is
weighted by the sample size obtained in each state, this percentage drops to 22.6%.
When the data are weighted by the number of registered trucks above 10,000  Ib
GVWR/GCWR, the percentage drops to 21.0%.
                                  47

-------
as.u
99.8
99.5
99
98
95
90
80
70
.1 60
+->
1 50
c 40
fi
0 30
jz JU
01
•S 20
10
5
2
1.0
0.5
0.2
0.1
0.05
0.01




*V_ A
X




















^s
^




















k\
A
^V^ '
•^














Data
I 	 QCa
• Ca
AIM
• Ni




(^
?JK
vS
N
N














Source
lifornia (1971) 172 Combination Vehicle
lifornia (1965) 5.838 Diesel Trucks
jshington (1972) 531 Trucks,
3 or More Axles
(w Jersey 1972) 1000 Trucks
3 or More Axles





i

WO\
vS
N
















L\
t> X.
^


















y5;
o
















^
!^§
s, \





















^A
\N
\




















s.A
^



80
82
84
                         86      88      90      92
                         Enforcement Limit, dB(A) at 50 Ft
Figure 10.  Enforcement Limit, dB(A) At 50 Ft
                                                       94
                                                       96
                                                       98
100
                                   48

-------
aa.y
99.8
99.5
o 99
S 98
CD
>

1 5 2 1.0 0.5 0.2 0 1 =\ \ \ — \ \ \ — — — — — — ~ I I X Xs \ \ *s I — All Trucks (N = 1394) ] — All Buses (N = 93) ] \ \ \ N I \ \ 'N \ N \ I V \ I — — — — — — — N,- 76 80 84 88 92 Peak Passby Noise Level, dB(A) at 50 ft 96 100 Figure 11. Cumulative Distribution Of Peak Passby Noise Levels For All Trucks And All Buses At Speeds Over 35 MPH 49


-------
                       Table 6
    ALL TRUCKS ABOVE 10,000 LBS GVWR OR GCWR
State
CA
CO
IL
KY
MD
NJ
NY
PA
TX
WA
Source
W.L.
BBN
BBN
BBN
Md. DOT
BBN
BBN
W.L.
BBN
WA-72
Mean Noise
Level
85.4dB(A) (a)
84.6
89.1
88.8
88.1
87.2
88.8
86. 2 (a)
83.7
86. 6 (a)
Mean Speed
_
51. 7mph
57.2
61.3
-
56.5
60.0
-
56.1
-
% Above
90. 0 dB(A)
5.0%
10.0
42.0
40.0
30.0
20.0
43.0
13.0
12.5
16.0
mean percentage exceeding given noise level:
                                  23.1%

(a) median
                         50

-------
    Table 7 shows the same results by type of truck for the nine states in
which data were obtained in 1973.  The mean percentages of trucks exceeding
90.0 dB(A)  ranges from 1.9% of 2-axle trucks  to 36.1% of 5-axle trucks.
    A crucial distinction must now be made.  The fact that approximately 23%
of all trucks observed in these surveys exceeded 90.0 dB(A) does not mean
that 23% of all registered trucks above 10,000  Ib GVWR/GCWR will exceed this
level.  This is because larger trucks operate many more miles per vehicle per
year than smaller trucks do and accordingly show up more frequently in surveys
than their actual numbers would indicate.  For example, 2-axle trucks average
10,600 vehicle miles per year, while 5-axle trucks average 63,000 vehicle miles
per year  (60).
    Using data from the 1972 Census of Transportation - Truck Inventory and
Use Survey (61),  the following breakdown was obtained for the population of
registered trucks  above 10, 000 Ib  GVWR/GCWR.

          TRUCK POPULATION OVER 10,000 POUNDS GVWR/GCWR
    2-axle straight  truck                               71.7%
    3-axle straight  truck                               10.6%
    3-axle combination truck                             2.4%
    4-axle combination truck                             5.3%
    5-axle combination truck                             8.1%
    Not reported or other                                1.9%
                                                     100.0%

    Table 8 shows that when these percentages are multiplied by the mean per-
centages  of each type exceeding 90.0 dB(A) from Table 7, a total of about 7% of
all registered trucks above 10,000 Ib GVWR/GCWR exceed 90.0 dB(A) at freeway
speeds.
                                   51

-------
                        Table 7
   2 AXLE STRAIGHT TRUCK ABOVE 10,000  LKS GVWR
State
CA
CO
IL
KY
MD
NJ
NY
PA
TX
Source
W.L.
BBN
BBN
BBN
Md. DOT
BBN
BBN
W.L.
BBN
Mean Noise
Level
81. OdB(A) (a)
80.4
83.1
82.9
83.9
82.3
85.1
81. 2 (a)
78. G
Mean Speed
-
50. 9mph
55.7
57.7
-
55.7
59.4
-
54.6
% Above
90.0 dB(A)
1.2%
1.9
1.0
1.0
3.5
0.6
6.0
0.9
0.6
moan percentage exceeding given
noise level:                                        1.!
              3 AXLE STRAIGHT TRUCK
CA
CO
IL
KY
MD
NJ
NY
PA
TX
W.L.
BBN
BBN
BBN
Md. DOT
BBN
W.L.
W.L.
BBN
85. 2 (a) (b)
84.1
85.8
87.7
87.5
84.7
88.0 (a)(b)
84. 5 (a) (b)
84.8
-
47.7
54.5
59.9
-
57.4
-
-
50.6
8.0
1.2
9.0
*
*
*
26.0
2.0
*
mean percentage exceeding given
noise level:                                        9.3%
(a)  median

(b)  all 3 axle trucks
 *  insufficient data


                              52

-------
                  Table 7 (Continued)


          3 AXLE COMBINATION TRUCK
State
CA
CO
IL
KY
MD
NJ
NY
PA
TX
Source
W.L.
BBN
BBN
BBN
Md. DOT
BBN
W.L.
W.L.
BBN
Mean Noise
Level
85. 2 (a) (b)
83.8
86.0
87.8
86.6
85.7
88.0 (a) (b)
84. 5 (a) (b)
83.0
Mean Speed
-
51.9
55.7
59.0
-
57.2
-
-
56.5
% Above
90.0 dB(A)
8.0%
*
*
*
17.0
1.0
26.0
2.0
*
mean percentage exceeding given
noise level:                                      10.1
         4 AXLE COMBINATION TRUCK
CA
CO
IL
KY
MD
NJ
NY
PA
TX
W.L.
BBN
BBN
BBN
Md. DOT
BBN
BBN
W.L.
BBN
84. 2 (a)
84.8
87.1
88.0
87.9
86.7
88.8
85. 7 (a)
83.9
-
49.0
55.4
61.0
-
57.7
58.8
-
56.4
3.0
9.0
22.0
24.0
26.0
11.0
26.0
9.0
4.5
mean percentage exceeding given
noise level:                                       15.1
(a)  median

(b)  all 3 axle trucks
 *  insufficient data


                            53

-------
                  Table 7 (Continued)


          5 AXLE COMBINATION TRUCK
State
CA
CO
IL
KY
MD
NJ
NY
PA
TX
Source
W.L.
BBN
BBN
BBN
Md. DOT
BBN
BBN
W.L.
BBN
Mean Noise
Level
85.9 (a)
87.0
90.2
90.6
89.7
88.3
91.2
87. 6 (a)
87.5
Mean Speed
-
53.7
57.7
G2.6
-
58.7
61.6
-
57.9
% Above
90.0 dB(A)
7.0%
18.0
51.0
56.0
42.0
32.0
74.0
22.0
23.0
mean percentage exceeding given
noise level:                                      36.1%
(a) median
                           54

-------
                           Table 8

    TRUCKS EXCEEDING 90.0 dI3A AT SPEEDS OVER 35 MPH
2 axle straight truck

3 axle straight truck
3 axle combination

4 axle combination
5 axle combination

All other (b)
% of all
trucks above
10, 000 Ibs (a)
71.7%
10.6
2.4
5.3
8.1
1.9
100. 7%
% of type
exceeding
90.0dB(A)
1.9%
9.3
10.8
15.0
36.1
36. 1 (c)
% of all trucks
above 10, 000 Ibs
affected (a)
1.4%
1.0
0.3
0.8
2.9
0.7
7.1%
(a)   Estimates are for all trucks over 10,000 pounds GVWR or GCWR,
     including trucks not involved in interstate commerce.

(b)   "All other" includes straight truck with trailer,  combinations with
     6 or more axles, and combinations  not specified in the 1972 Census
     of Transportation survey.

(c)   No data available.  Percentage exceeding noise level is assumed to
     be the same as for 5 axle combinations.
                               55

-------
ANALYSIS OF LOW SPEED (UNDER 35 MP1I) SURVEY DATA
     Table 9 shows the percentages of trucks above 10,000 Ibs GVWR/GCWR
that exceeded 86 dB(A) under low speed acceleration conditions in various states.
These data were collected at roadside sites  in seven states with acoustic charac-
teristics similar to those of the sites used for the collection of high speed data,
except in Maryland and Virginia.   At these two sites, the paved surface covered
the entire distance between the roadway and the microphone, and there was no
grassy shoulder area. A site correction factor of -1.5 dB has been assumed for
the data obtained at these sites in order to permit direct comparison with the
other data, most of which was taken at open sites over a "soft" surface.
     A comparison of the results shown in Table 9 with those of Tables 6 and 7
demonstrates  not only that similar total percentages  of trucks were observed
to exceed 86 dB(A)  under low speed acceleration as exceeded 90 dB(A) under high
speed conditions, but also that these percentages are very nearly the same for
each class of trucks considered separately.  For example, 2% of all 2-axle trucks
exceeded 86 dB(A) under low speed acceleration, while 1.9% exceeded 90 dB(A)
under high speed freeway conditions.  For 4-axle trucks, the results are 21%
and 15%, respectively.  In this sense, an 86 dB(A) limit under low speed condi-
tions can be considered to be about as stringent as a  90 dB(A) high speed limit.
     The calculations in Table 10 yield an estimate that at the present time about
8% of the nationwide truck fleet over 10,000  pounds exceeds 86 dBA during low-
speed acceleration measured at an open site over a soft surface.
ANALYSIS OF STATIONARY RUNUP TEST DATA
     EPA conducted a small-scale investigation to determine that the Stationary
Runup Test (SHUT) is suitable with respect to practical enforcement, particu-
larly in terms of repeatability, and to check that predicted violation rates as
enforced would be consistent with those of the low-speed passby test.  A state-
weighing station in Virginia cooperated by allowing a survey team to request the
participation of drivers as they appeared for weighing their trucks.  Sixty
trucks were measured by the method outlined in the appendix.
                                    56

-------
                        Table 9

    PERCENTAGE OF TRUCKS AT OR ABOVE 86 dB(A)
        DURING ACCELERATION BELOW 35 MPH

 State
 California
 Colorado
 Florida
 Maryland (a)
 Missouri
 Texas
 Virginia (a)
 Mean
 Excluding
 California
 * insufficient data
(a). -1.5 dB  site  correction factor assumed (see text)
2-Axle
2%
3
1
*
0
2
*
2%
3-Axle
12%
6
7
11
28
13
11
13%
4-Axle
*
27
13
20
27
*
20
21%
5-Axle
20%
24
36
40
49
26
42
36%
All Trucks
10%
17
10
35
39
17
40
24%
                            57

-------
                              Table 10

              PERCENT OF TRUCKS OVER 10,000 POUNDS

                 EXCEEDING 86 dB(A) UNDER 35 MPH

              % of Trucks Above   % of Type Ex-      % of Trucks Above
No. of Axles   10. OOP pounds  (a)    ceeding 86 dB(A)  10,000 pounds Affected (a)
2 axle
3 axle
4 axle
5 axle
All other (b)
72%
13
5
8
2
2%
13
21
36
36 (c)
1.4%
1.7
1.1
2.9
0.7
                   100%                                  7.8%

a)  Estimates are for all trucks over 10,000 pounds GVWR or GCWR,
    including trucks not involved in interstate commerce.

b)  "All other" includes  straight truck with trailer, combinations with 6
    or more axles, and combinations not specified in the 1972 Census of
    TnmsporUition survey.

c)  No data available. Percentage exceeding noise level is assumed to be
    the same as for 5 axle trucks.
                                 58

-------
    A representative from the Bureau of Motor Carrier Safety explained to
each driver the technique required to achieve a maximum engine runup.  Four
runups were performed for each truck and the noise level measurements were
recorded.  In many cases, the first attempt by the driver did not produce the
rapid engine acceleration necessary for the test.  However,  in most cases the
tost was performed properly in subsequent attempts.
    Tins average of the three hignest noise levels obtained from the four tests
was used to characterize the SRUT level for comparison with the EPA standard
level  of 88 dB(A).  The consistency of the three highest levels was  such that
for 93% of the trucks tested, the range of noise levels was  1. 5 dB(A) or less.
Of the small population tested 35% exceeded the noise level standard of 88 dB(A).
CLASSIFICATION OF TRUCKS  INTO CATEGORIES
    The studies performed indicate that truck mean noise levels increase with
vehicle size (or number of axles) and speed.  Accordingly, regulations have been
promulgated for high and low speed truck operations in order to quiet both engine-
related noise and tire noise. An effort was also made to develop a suitable classi-
fication for trucks based on weight or number of axles in order to require the use
of best available technology in trucks of all sizes.
    Figure 12 presents cumulative distributions of peak pass-by noise levels
over 35 MPH at 50 feet for trucks by number of axles.  These data were obtained
in New Jersey in 1973, but the differences observed between different vehicle
classes are typical of other states as well.   Mean noise levels for  2-axle, 3-
axle,  4-axle, and 5-axle trucks are 82,  86,  87, and 89 dB(A), respectively.
The greatest difference in means occurs  between 2 and 3-axle trucks.  Since
this is  also the break  point between medium and heavy  duty trucks,  the
Agency examined  the feasibility of  classifying trucks over 10,000 pounds into
two categories in order to promulgate stricter regulations for smaller vehicles.
    Although there  is a significant difference between the mean noise levels
of medium and heavy duty trucks,  there is  considerable overlap in the
distributions of noise levels of trucks  of  different sizes currently on the
road.   The basic problem is  that noisy propulsion systems are not confined
to heavy duty trucks.  Many truck manufacturers offer  and have traditionally
sold the same engines in  trucks having 2 or 3  axles.   For example,

                                   59

-------
CS
o
          I
          01
          <£
          'o
  99.9
  99.8
  99.5
    99
    98

    95
    90
          0)
.2   80
O
01
§
              70
              60
              50
              40
         3  30
o
*—
<
          0)
          O)
          03
          ^
          0)
          if
          I
    20
    10
             1.0
             0.5
             0.2
             0.1
1
_ ^N


—

—



— _







—





i
i
\
\





















i
i
\
y
\
\
\
N


\
\
\
^L
\.
\
^k
\








1
V
•
•
X.
•
• ,
\ \
\
\ \
v
\
\
\









N^



1
1



\\
\ \
• •
\\
k \ *
\ \ •.
N \
\ \
\ \
\

X ^T
^k ^
>,


1
"1
Passenger Cars
(Data Collected
in Baltimore)
— — 2-Axle Trucks
(Six Wr
•— - 3-Axle
— . — . 4-Axle
	 5-Axle




1
*
^



\

\


\

^
1




'..
\

»L
\
• •
, \ \
V * *•
\ \

^k \ i
N \

V
^
1
eels)
Trucks
Trucks
Trucks














•
\


K \.
V

\
•...


1
_
—


—

—



_







—



\
***.
1 \
 Figure 12.
      60    70     72     74     76    78     80    82    84     86     88    90    92    94     96     98   100
                                           Peak Passby Noise Level, dB(A) at 50 ft
   Cumulative Distribution of Peak Passby Noise Levels for Various Classes of Trucks at Speeds
   Over 35 MPH.

-------
according to MVMA data,  3.5% of all new medium duty trucks  sold in 1972 were
powered  by diesel engines similar or identical to  those  engines used on heavy
duty trucks.   The same situation has characterized the  use of noisy gasoline
engines.   For this reason, further classification of motor vehicles  into
categories over 10,000 pounds GVWR is not feasible for the low speed standard.
    An analysis of the feasibility of classifying trucks at speeds over 35 MPH
indicated that 88 dBA could probably be achieved by  2-axle vehicles, since they
use fewer tires than multi-axle combination vehicles.  However, the analysis of
the environmental impact of the high speed standard indicated that highway noise
levels are determined almost entirely by the noise levels of the heaviest trucks
(those with 4 and 5 axles).  The additional assumption of an 88 dB(A) limit on
2-axle trucks above 10, 000 Ibs GVWR and an 82 dB(A) limit on all passenger
cars and light trucks in addition to the proposed standards in the analysis  pro-
duced essentially no further decrease in highway noise levels.
    The Agency considered limiting the coverage of the Interstate Motor Carrier
Regulations to trucks over  26,000 pounds GVWR/GCWR or to trucks having 3
or more axles because several states had requested that coverage be limited so
that more stringent state regulations could be applied to the medium duty trucks.
However, limiting coverage to trucks over 26,000 pounds would exclude 56% of
all trucks over 10,000 pounds GVWR/GCWR from Federal regulation.  Limiting
coverage to trucks over 3 axles would exclude 72% of all trucks over 10,000
pounds GVWR/GCWR from Federal regulation.
    Even though only a small percentage (2%) of all  medium duty trucks exceed
86 dB(A) at speeds under 35 MPH and 90 dB(A) at speeds over 35 MPH, the
actual number of trucks exceeding the standard is not small. Since the intent
of Section 18 is clearly to provide uniform nationwide noise regulation for all
vehicles involved in interstate commerce,  and since limitation of coverage would
allow medium duty trucks to go unregulated in many states, the Agency has
determined that at this time medium and heavy duty  trucks over 10,000 pounds
operated in interstate commerce shall be subject to  identical Federal regulations.
                                  61

-------
POTENTIAL DEGRADATION ()!•' VKIMCLKS
    Since a l:irge proportion of medium duly vehicles at tho prosonl time have
noise levels that are considerably below 90 dB(A) at speeds above 35 MPH, it
has been suggested that degradation of these vehicles could occur until their
noise levels reach 90 dB(A) due to the promulgation of Federal regulations.
At the present time a few states enforce noise regulations equal to the proposed
Federal regulations, while in other states vehicle noise is currently unregulated.
Therefore, there is no a priori reason to believe that the change from this situa-
tion to one of Federal regulation should cause any vehicle to become noisier than
it would be otherwise.
    Nevertheless,  some data are available  that can be used to investigate the
likelihood of degradation at speeds in excess of 35 MPH.  In Figure 10 surveys
of noise level distributions were presented for certain vehicle populations in
Washington State (1972), New Jersey (1972), and California before and after
stale noise regulations were promulgated (1965 and  1971).  Unfortunately, the
vcluclc populations and other conditions (e.g. speed, grades, and measurement
sites) were not uniform in all states.  The New Jersey  and Washington studies
examined vehicles of 3 or more axles, while the 1971 California study examined
only combination vehicles.  Since combination  vehicles are the heavier portion
of the heavy trucks having 3 or more axles, the California noise levels
measured in the 1971 study would be expected to be above the noise levels
measured in the other states.
     An analysis of Figure 10 indicates that the 1971 California noise distribution
is about one decibel above the other distributions at noise levels below 84 dB(A).
The distributions are virtually identical between 84 and 92 dB(A) for all states in
all years and for all vehicle populations.  Above 92 dB(A), the effect of the
California noise regulation is noticeable, since a smaller proportion of
of vehicles are currently above 92 dB(A)  in California than in other states.
     As expected,  no evidence exists to indicate that vehicles degrade more
when regulated than when unregulated.  In fact, since the California noise
level distribution for very heavy combination vehicles (tractor trailers) is
                                    62

-------
only one decibel above the distribution of medium and heavy trucks in other
states, the state regulation may well have resulted in a reduction of the noise
emissions of trucks that were already below 90 dB(A) prior to regulation.
    Testimony from muffler manufacturers during EPA public hearings indi-
cated that an increased demand for their better mufflers has been noted in
noise-regulated areas.  These manufacturers and the American Trucking Asso-
ciation (ATA) indicated they had no reason to believe that degradation had
occurred in any states with noise regulations.
    However, it is possible that when motor carriers replace the mufflers on
their vehicles in order to comply with the Federal regulation  requiring an exhaust
system "free from defects which affect sound reduction, " they will occasionally
choose a muffler that is not  as good as the original equipment.  This is unlikely to
occur with heavy duty trucks because it would lead to violation of the performance
standards.  However, it could happen with some medium duty trucks that originally
had noise levels below the standard.  The agency investigated the possibility of
requiring a muffler "comparable to original equipment," but this requirement was
determined to be undesirable because in many cases the original muffler supplied
on old trucks did not sufficiently attentuate noise to meet the  Federal emission
standards.
    In the event that future  studies of the noise levels of in-serve medium duty
trucks indicate that motor carriers are using replacement mufflers that are
inferior to effective original equipment,  regulations can be developed to label
mufflers, and the Interstate Motor Carrier Regulations can be revised to require
the use of mufflers comparable or superior to original equipment.  Muffler
manufacturers already provide information about the effectiveness of their mufflers
on specific engine models, although measurement methods vary to some degree.
Consequently,  if degradation is found to occur, a remedy can be developed relatively
easily.
                                    63

-------
                                Section 5

            IMPACT OF THE FEDERAL NOISE REGULATIONS

     Three kinds of potential impacts are associated with the promulgation of
the Interstate Motor Carrier Regulations.  An economic impact will occur
because motor carriers will be required to retrofit those motor vehicles that
arc not in compliance with the regulations.  An impact on highway and urban
noise levels will occur because many vehicles will be made quieter. Finally,
some States and local jurisdictions may be required to alter their existing
regulations because the Federal regulations are preemptive.
I-ICONOMIC IMPACT OK TIIK REGULATIONS
     According to Ihc :in:ilysis presented in Section .1,  approximately 7-8% ol
nil i-cnislcrcd (nicks ?il»ove K), 000 II) (1VWK/GCWK will initially I'nil In comply
with (he standards its measured :t( typical roadside sites.  Until such time us
sl;ile :md local jurisdictions adopt these standards as their  own, the standards
will  apply only to motor carriers engaged in interstate commerce.
     There is no direct method for determining precisely how many trucks above
10,000 Ib GVWR/GCWR are engaged in interstate commerce.  Based on truck
population statistics, industry information, and inputs to the Advanced Notice of
Proposed Rulemaking Docket,  it appears that at least 1,000,000 of the 5,147,000
trucks above 10,000 Ib GVWR/GCWR will be affected C62.63.64'65).
     As discussed in Section 3, the heaviest impact of the standards will fall on
multiaxle trucks, and available statistics indicate that an average of $114 was
required in 1973 to bring these trucks into compliance with local standards that
were identical to the Federal Standards.
     Since prices of most commodities and services have risen significantly over
the past year and appear likely to continue to rise in the next year, the average
retrofit cost can be expected to rise also.  A reasonable average  retrofit cost
estimate for 1975 is therefore $135 per vehicle in violation of the standards.

-------
    U, ns .1 worst case, it is assumed that all 15. 2 million motor vehicles above
10,000 pounds GVWll/GCWll would be required to meet the standards, and thai
8% of them would require retrofit at a cost of $135 per vehicle, then the total
direct retrofit cost could be as high as $5(i million.
    Although the number and composition of trucks operating in interstate
commerce is not known, most of the 5-axle trucks are thoueht to be used  for
hauling intercity freight, and most of them are involved in interstate commerce.
Table 10 indicated that this group of trucks  included half of all the trucks  over
10,000 pounds GVWR expected to exceed the standards.  Accordingly,  the total
retrofit cost is likely to be at least $28 million.
    In 1970, the average revenue per intercity vehicle mile for Class I intercity
carriers of all types was 91 cents.  For  Class I intercity carriers of general
freight, average revenue was $1. 24 per intercity vehicle mile.   Total expenses
for the latter group of carriers averaged $1.20 per intercity vehicle mile. Of
these expenses, wages represented 46 cents; repairs and servicing, 8 cents;
fuel and oil, 3 cents; tires and tubes, 2 cents; and depreciation and amortiza-
tion,  5 cents.  Direct wages represent 38% of expenses per  intercity vehicle
mile and 52 cents of every truck revenue dollar.  Social security taxes, work-
men's compensation payments, and welfare benefits bring total wages to 60 cents
per truck revenue dollar^    .
    A retrofit cost of $135 per vehicle is not a major burden for the interstate
motor carrier industry.  For a truck running 50,000 revenue miles per year,
a $135 retrofit cost represents an  increased expense of $. 003 per revenue
mile when amortized over a single year.   When this increase is compared
with 1970 average expenses of $1.20 per  revenue mile, it can be seen that
retrofit cost is not an obstacle to lower noise emission standards.
    Additional costs include loss of revenue resulting from  trucks being out of
service during retrofit.  Also,  the installation of a  suitable  muffler may in
some cases increase the back pressure on the engine and in turn increase the
fuel consumption.  Considering the wide  variety of mufflers  available^  ,
however, a significant increase in back pressure is avoidable.
                                    65

-------
     Some factors reduce the total cost to the trucking industry.  First,  the
muffler on a line-haul truck is normally replaced at 1-1/2 to 2 year intervals.
Thus,  of those trucks that require a replacement muffler, about one-half will
be installing a new muffler even in the absence of the regulations.  In these
cases, the cost incurred will be the difference between that for the required
muffler nnd that for the one that would have been installed anyway, and ilie
difference is within the range of a few dollars. Secondly, for those trucks
requiring installation of a more  efficient fan, the amount of engine power wasted
in driving a fan unnecessarily will be reduced. Standard fans on diesel  engines
typically consume 15 to 25 horsepower*  '.  The addition of a thermostatically
controlled fan clutch can decrease fuel consumption by 1 to 1. 5%^  ' and can
reduce operating cost for the life of the truck. With these considerations, the
long-term cost of compliance with the noise regulations may be less than that
given above.
     Component suppliers appear to be capable of providing the needed retrofit
components within the one year time period.  The muffler manufacturing industry
is capable of significantly expanding its muffler production, probably by a factor
of two, because it already has the necessary facilities and material*7 '.
     In the case of tires a large majority of such trucks will require new tires
within a year regardless of the existence of the regulation. There should not,
therefore,  be  a significant increase in the total truck tire production required,
though there may be a slight shift in production from some tread patterns to
others.
     Other retrofit items discussed in Section 3 are in current production, and
no significant  problems are foreseen in meeting the production levels necessary
to retrofit the small percentage  of trucks that will need these items in order to
comply with the standards.
ENVIRONMENTAL IMPACT OF  THE  NOISE EMISSION STANDARDS
     The noise emission standards impact directly those trucks which presently
make the most noise and require that they be quieted to levels that are feasible
from a cost and technology standpoint within one year of final promulgation.
                                     66

-------
The principal noise reduction will be of the intrusive noise peaks which have
been widely acknowledged as more objectionable to people than much lower
                         (71)
levels of continuous noise ^  '. These peaks can be 12 dB or more above
ambient highway noise levels.  Therefore,  significant noise reduction
will be realized within a year, producing substantial benefits  in terms of public
health and welfare as indicated by a decrease in community noise levels near
highways.
    In a study performed under contract to the  Environmental Protection
               (72)
Administration *  ', L,  levels were computed for an interstate highway, using
hourly traffic volume statistics submitted by the Maryland Department of Trans-
portation.  This study was carried out  using a modified version of the Highway
Noise Prediction Model of the Transportation Systems Center, U. S. Department
of Transportation.  Baseline L , (day-night sound level) levels were computed
using actual distributions of noise levels for various classes of trucks as
measured in Maryland.   Comparison levels were then computed using noise
level distributions corresponding to several alternative regulation strategies.
    The results of the study indicated that a 90  dB(A) limit for all trucks above
10,000 Ibs GVWR/GCWR will produce a 3.6 dB  decrease in L^ for a typical
East Coast Interstate highway.  This represents a decrease of about 50% in
the average sound energy near the highway.
    An additional study of the impact of the Federal regulations has been per-
formed using the Highway Research Board Design Guide model.  This model
is designed to perform an analysis of L  (A-weighted equivalent sound level)
                                     etj
at 50 feet  from the right of way of highways during the design  hour.  The
model was used to estimate the impact  of the regulations in both highway and
normal urban conditions.
    It was found that at 50 feet from a typical highway, the L   during the  design
                                                        eq
hours (peak hour) is 80.9 dB for cruise conditions.   This  analysis is predicated
on the following assumptions:
                                    67

-------
    (1)  during the worst Imfl'ir hour there ;vre 7200 vehicles per hour I r;iv(
        at. :in :ivur:«ne spciil ol !>!"> in. p. h.
    (2)  the mixture of vehicles is 10 peri-enl lirsivy (Inly trucks :uid !)() percent
        medium duty trucks,  light trucks,  and  automobiles.
    (3)  the typical highway has 6 lanes of traffic.
    The tjITect  of the Federal regulations will be a significant reduction in highway
noise levels. The results of the analysis indicate that 2 years after the operating
rule goes into effect, the L   for highways during the design hour will have been
                         eq
reduced by 2.3  dB(A).  The level will drop from 80. 9 to 78. 6 dB(A).
    An analysis of normal urban conditions indicated that on city streets, the A-
weighted equivalent level is 68.1 dB for a mixture of 1 per cent heavy trucks, 6
per cent medium trucks and 93 per cent automobiles, traveling at an average speed
of 27  m. p. h.
    The Federal regulations will affect only a few trucks on city streets because
most  of the traffic on urban streets is due to automobiles and light or medium
trucks.  Thus,  the rule will bring about only a 0.3 dB(A) reduction in noise levels.
A significant reduction in urban noise levels will not occur until medium  duty
trucks and automobiles are regulated to lower levels, since they are the dominant
noise source in urban areas.
RELATIVE STRINGENCY OF  FEDERAL REGULATIONS AND THOSE OF OTHER
JURISDICTIONS
    Jurisdictions with noise regulations planned or in effect have expressed an
interest in the  relative stringency of the EPA regulations because their regula-
tions may be preempted by the Federal regulations.  Test methodology and all
techniques of enforcement must be compared in order to assess  different regula-
tions in terms  of relative stringency.  Maximum noise emission levels alone
can be very misleading.
    A pronounced effect on noise as measured  exists as a result of the surface
texture between vehicle and microphone.  The EPA standards address this prob-
lem in that the stated levels apply to typical roadside sites with  acoustically
soft reflecting  surfaces between the vehicle and the microphone.
                                      68

-------
     Other factors affecting regulatory stringency in terras of measurement metho-
dology cim be as important as site variation.  Microphone placement has a critical
(ifTucl. on measured noise levels.  One city noise regulation calls Tor a microphone
location 2.r> feet from the lane edge.  This is .'31  1'ccl from the lane ccntcrlinc and
the regulated level would theoretically need to be 4 dli higher than the KI'A standard
sp'jcificE in order to be  of similar stringency (:'!! other fcctcrs bcin.£ ccpi?.!).  In
actual practice, at such close distances, ground surface reflections would result
in a difference less than 4 dB.
     Another area of variability deals with enforcement techniques and policies.
The difficulty in assessing relative stringency is compounded by the fact that these
techniques and policies, as actually enforced, are sometimes not made  clear by the
written regulations.  A western State has a 90 dB(A) highway noise limit but has chosen
not to issue citations if the enforcement officers determine that tire noise predomi-
nates.  As enforced, this standard would be less stringent than an identically worded
one  in a jurisdiction enforcing against total noise emission.  A New England State
has  a noise regulation which appears to be as stringent as the EPA standards,
and which calls Cor increased stringency in the next year.  Even though the wording
of its regulation calls for compliance under all conditions of grade  and accelera-
tion, as does the EPA regulation, that State has chosen to enforce the regulation
under level-road, no-acceleration conditions.  The actual violation rate is for
this reason much lower than the predicted violation rate for the EPA regulations
and therefore the actual stringency is less.
     The categories of vehicles subject to different State and local noise regula-
tions vary.  Those regulations which exclude  certain classes of vehicles are less
stringent as applied than regulations which include these vehicles.  Some local
regulations are based on measurement tests that are entirely different from the
Federal tests. Determination of the relative  stringency in such cases would re-
quire extensive technical research.
     Where measurement methodology is absent from a written regulation,
relative stringency cannot be determined.  Tolerances in measurement condi-
tions or vaguely defined conditions (e. g., measurement distance defined as "50
feet  or nearest property line") and the use of different frequency weighting
scales in different regulations also make comparison almost impossible.

                                     69

-------
    Table 11 presents information on the noise limits currently in effect in a
large number of State and local jurisdictions.  Many of these jurisdictions
currently appear to have regulations identical to the Federal regulations, but
as mentioned, this can only be verified through a comprehensive analysis of
                                                                        (73)
the test measurement and enforcement procedures used in each jurisdiction    '.
                                      70

-------
                                       TABLE 11
        TABLE H  QUANTITATIVE NOISE REGULATIONS FOR VEHICLE OPERATION
                              (Maximum Levels at 50 ft)
Limits Under
Vehicle
Type
Trucks














State, County, or City
California (over 6000 lb)*
Chicago (over 8000 lb)
Colorado (over 6000 lb)
Connecticut
Cook County (over 8000 lb)
Idaho*
Indiana (over 7000 lb)
Minneapolis (over 6000 lb)
Minnesota (over 6000 lb)
Nebraska (over 10,000 lb)
Nevada (over 6000 lb)
New York
New York City (over 6000 lb)
Oahu (over 6000 lb)
Pennsylvania (over 7000 lb)
Salt Lake County
(over 6000 lb)
Level
Road
Only
82
—
82
82
^«B
	
	
	
	
	
	
	
	
	
— —
All
Roads
Now
86
86
86
86
86
92
88
88
88
88
86
88
86
73-86
90
86
35 mph
Change
Year
—
—
—
1975
~™
—
1975
1975
1975
—
—
—
1974
—
^^
dB(A)
All
Roads
Then
—
—
—
84
«••
—
86
86
86
—
—
—
73-84
—
^ —
Limits Over 35 mph dB(A)
All
Roads
Now
90
90
90
90
90
92
90
—
90
90
90
—
90
86
92
~
All
Change Roads
Year Then
—
—
—
1975 88
"•"• ^~
—
—
—
—
—
—
—
1974 84
—
_ v •_«
*No citation if tire noise predominates
rAt 20 ft or more

-------
                             REFERENCES
 1.   Information on Levels of Environmental Noise Requisite to Protect Public
     Health and Welfare with an Adequate Margin of Safety, U.S. Environmental
     Protection Agency, March 1974.

 2.   Ibid., p.  40.

 3.   Ibid., pp. B4-5.

 4.   Effects of Noise on People, NTID 300.7.

 5.   Truck Noise I - Peak A - Weighted Sound Levels Due to Truck Tires,
     National Bureau of Standards Report prepared for Department of Transporta-
     tion, Report No.  OST-ONA 71-9, Sept. 1970.

 6.   Ibid.

 7.   Personal communication with W. H.  Close,  Department of Transportation.

 8.   Op. Cit., DOT Report No. OST-ONA 71-9, p.  3-4.

 9.   "Transportation Noise and Noise from Equipment Powered by Internal
     Combustion Engines, " U.S.  Environmental Protection Agency, Report NTID
     300.13, Dec. 31,  1971, p. 94.

10.   Ibid., p.  100.

11.   Ibid., p.  102.

12.   "Diesel Exhaust and Air Intake Noise," Stemco Manufacturing Company for
     Department of Transportation,  Report No. DOT-TSC-OST-73,  March 1973.

13.   Ibid.

14.   Data from Service Engine Company, Cicero, Illinois.

15.   Op. Cit., NTID 300.13,  p. 103.

16.   Ibid., p.  102.
                                    72

-------
17.  Wyle  Ljltoi'itorics, personal communic:ilion with  Flcsc-A-LiU1 Corponlimi,
    Tacoma, Washington.

18.  Wyle Laboratories, personal communication with Advanced Products Group,
    White Motor Company, Torranoe, California.

19.  Shipe,  M. D.,  "Operating Principles of the Schwitzer Viscous Fan Drive, "
    Schwitzer Division of the Wallace-Murray Corp.,  Indianapolis, Indiana,
    March 1971.

20.  Op. Cil., NTID 300.13, p.  103.

21.  Published literature from Schwltzer Division of the Wallace-Murray Corpo-
    ration, Indianapolis, Indiana.

22.  Op. Cit., NTID 300.13, p.  104.

2:5.  Tbid., p. 102.

24.  fbid., p. 104.

25.  Law,  R. M. , "Diesel Engine and  Highway Truck Noise  Reduction," Society
    of Automotive  Engineers (SAE) Report 730240,  Jan.  1973.

26.  Op. Cit., Data from Service Engine Co.

27.  Op. Cit., NTID 300.13, p.  7.

2H.  Ibid., p. 103.

29.  Literature from Donaldson  Company, Minneapolis, Minnesota.

30.  Op. Cit., ODT-TSC-OST-73, March 1973.

HI.  Davisson, J.A., "Design and Application of Commercial Type Tires,"
    SAE Paper SP 344, Jan. 1969.

32.  Wik, T. R., and Miller, R.  F. , "Mechanisms of Tire Sound Generation, "
    SAE Paper SP 373, Oct. 1972.

33.  Wyle Laboratories personal communication, with major tire companies.

34.  Op. Cit., DOT Report OST-ONA 71-9.

35.  Ibid., p. 42.

36.  Ibid., p. 44.
                                   73

-------
37. Ibid., p. 42.

38. Op.  Cit., Data from Service Engine Co.

39. Op.  Cit., NTID 300.13, p. 92-95.

40. Close, W. H., and Atkinson, T., "Technical Basis for Motor Carrier and
    Railroad Noise Regulations," Sound and Vibration, Vol. 7, No. 10,
    Oct. 1973.

41. Op.  Cit., NTID 300.13, p. 92-93.

42. "Community Noise, " U. S. Environmental Protection Agency, Report NTID
    300.3, Dec. 31, 1971, pp A-5, A-7.

43. Ibid., p. 4.

44. Op.  Cit., NTID 300. 3, pp. A-5, A-7.

4.r>. (bid., p. 5.

'Ifi. Young,  R.W. ,  "Single Number Criteria for Room Noise," JASA, 36, 2,
    Feb. 1964, p. 289.

47. Klumpp, R.G., and Webster, J. C., "Physical Measurement of Equal Speech
    Interfering Navy Noises," JASA, 35,  Sept.  1963, p. 1328.

48. Wells, R. J., "A New Method for Computing the Annoyance of Steady State
    Noise versus Perceived Noise Level and Other Subjective Measures, " JASA,
    46, July 1969, p.  85.

49. Webster, J. C., "Affects of Noise  on Speech Intelligibility," Proceedings of
    Conference, Noise as a Public Health Hazard, Washington, D. C., June 1969,
    ASI-IA Report #4.

50. Op.  Cit., NTID 300.13, p. 94.

51. "Research  on Highway Noise Measurement Sites," Wyle Laboratories  Report
    for California Highway Patrol, March 1972.

52. "Use of Motor Vehicle Noise Measuring Instruments, " California Highway
    Patrol Report,  1965.

53. "California's Experience in Vehicle Noise Enforcement, " California Highway
    Patrol Report,  1965.

54. Foss, R. N. , "Vehicle Noise Study - Final  Report," Applied Physics Labora-
    tory, University of Washington,  Report for Washington State  Highway Commis-
    sion, Department of Highway, June 1972.
                                   74

-------
 55.  Unpublished data,  Bolt, Beranek and Newman.

 56.  Op.  Cit., "Use of Motor Vehicle Noise Measuring Instruments".

 57.  Op.  Cit., Exhibit G., (ONAC Docket M070).

 58.  Op.  Cit., "Vehicle Noise Study -  Final Report".

 59.  Op.  Cit., Unpublished Data, Bolt, Beranek and Newman.

 60.  1972 Census of Transportation - Truck Inventory and Use Survey,
     U. S. Department of Commerce, Bureau of the Census.

 61.  Ibid.

 fi2.  American Trucking Trends. 1972. by the American Trucking Associa-
     tion, Inc., Washington,  D. C.

 63.  "1973 Motor Truck Facts," by the Motor Vehicle Manufacturer Associa-
     tion, Detroit,  Michigan.

 64.  Response from American Trucking Association, (ONAC Docket M058).

 65.  Op.  Cit., 1972 Census of Transportation Truck Inventory and Use Survey.

 KG.  Op.  Cit., American Trucking Trends.

 67.  Op.  Cil., Literature from Donaldson Company.

 68.  Wyle Laboratories communication with the Schwitzer Division of Wallace-
     Murray Corporation and the Flex-a-lite Corporation, 1973.

 69.  Bolt, Beranek and  Newman, Inc. , Report No. 2563,  "The Cost of Quieting
     Heavy Cab-Over-Engine Diesel Tractors," July 1973.

 70. Op.  Cit., Wyle Laboratories personal communication with 3 major muffler
    manufacturers.

 71. Op.  Cit., NTID300.7.

72. Study conducted by Bolt, Beranek and Newman, Inc.

73. Maryland Department of Transportation submission to the Docket.
                                  75

-------
                               Appendix:
                    MEASUREMENT METHODOLOGY

     The procedures given herein are intended to permit measurement of the
 A-weighted sound level of individual motor vehicles under specified conditions.
 The methods are consistent with the required accuracy of measurement.
 Suitable instrumentation for the measurements is prescribed; standard (ideal)
 measurement sites are described; and appropriate  operational procedures are
 given for  carrying out the measurements.
 Applicable Documents
     ANSI SI. 4-1971, American National Standard Specification for Sound Level
 Meiers is appropriate for these procedures and is available from American
 National Standards Institute, 1430 Broadway,  New York, New York  10018.
 1 n strumentat i on
     A precision sound  level meter meeting all the requirements of ANSI SI. 4-1971
 throughout the frequency range from 50 Hz to  10,000 Hz for a Type I or  Type SIA
 instrument should be used for all measurements.  However,  a magnetic tape
 recorder, graphic level recorder,  or other device to record maximum sound
 level may be used for the measurement. In all such cases,  the overall per-
 formance  of the total system should conform to the  ANSI SI. 4-1971 requirements.
     The necessary auxiliary equipment for the sound level meter includes a
 mounting to hold the microphone at a height of 4 ft + 1 in (1. 2 m) above the
 ground, and a cable at least 15 ft (4. 5 m) in length, designed to be used with
 the sound  level meter.   The microphone manufacturer's instructions should be
 followed concerning the maximum permissible cable length.
    An acoustical calibrator of the microphone coupler type should be used for
 calibration of the measurement instrumentation.  The frequency of the calibra-
tion signal should be 1000 Hz, + 5%.  The calibrator should be checked at Icasl
annually by a method traceable to the U. S.  National Bureau of Standards to verify
the correct performance within + 0.5 dB.

                                   76

-------
    A windscreen should be used for all measurements to reduce the effects of
turbulence at the microphone surface.  An anemometer, accurate to within
+ 10% at 12 mph (20 kph),  should be used to determine the local velocity of
wind gusts prevalent at the time of the measurements.  The measurement of
wind velocity should be taken at the height of the microphone and approximately
10 ft from the microphone.
Calibration
    The sound level meter (including the entire sound instrumentation recording
system) should be calibrated with the acoustic calibrator immediately before
each series of measurements and at approximately 1/2-hour intervals during a
measurement  period.  The manufacturer's directions for the calibration pro-
cedure should be followed.  The entire measurement system, including all
cables,  but not the windscreen, should be included in the instrument chain for
this calibration.
    The entire measurement system should be calibrated, over the frequency
range between 50 and  10,000 Ilz, at intervals not exceeding one year,  by pro-
cedures of sufficient precision :ind accuracy to determine compliance with the
requirements  of Section 3 of ANSI SI. 4-1971.  If there is any reason to suspect
that the equipment has been altered or damaged, it should be given a complete
calibration, regardless of the date of the last complete calibration.
Standard Measurement Site
    The measurement site for roadside pass-by and stationary tests should
be such that the vehicle radiates sound into an essentially open space above the
ground.  This condition may be considered fulfilled if the site consists of an
open space free of large sound-reflecting objects (such as barriers, walls,
fences,  hills,  hedges, signboards, parked vehicles, bridges or buildings)
within the boundaries indicated in Figures Al and A2 for the pass-by and the
stationary vehicle measurements, respectively.
    For the purposes of this requirement, "large" means dimensions greater
than about one foot (0.3 m).  Objects that would not  be considered "large," and
are therefore  permitted within the measurement area, are fire hydrants, tele-
phone or power poles, and rural mail boxes, but not, for example, telephone
booths,  or trees of any kind.

                                    77

-------
Weather
    Weather conditions may adversely affect measurement precision.  Accord-
ingly, measurements should not be made during precipitation.  The wind
velocity should be read from the anemometer immediately before each series
of measurements and at intervals  of 1/2 hour during the measurement period,
if wind conditions warrant. Measurements should not be made when the
average continuous or gust wind speed exceeds 12 mph (20 kph).
Microphone Location
    For all measurements, the surface upon which the microphone is located
should be within + 2 ft of the plane of the road surface.  The microphone height
should be 4  ft + 1 in (1. 2 m +_2. 5  cm) above the surface upon which it is located.
    For the pass-by measurements the microphone should be located at a
distance of 50  + 1/2 ft (15  + 0.15 m) from the centerline of the nearest travel
lane.  The microphone should have a clear and unobstructed line-of-sight to
the entire side of the vehicle for all points along the roadway within 35 feet of
the point of nearest approach.
    For the stationary vehicle measurement the microphone shall be  located
50 + 1/2 ft  (15 + 0.15 m) from the fore-and-aft centerline of the vehicle, in a
plane normal to that centerline and passing within 3 ft (1 m) of the nearest
exhaust outlet.
Noise Measurement Procedures
    The following procedures should be followed to assure accurate results in
the measurement of motor vehicle noise emissions:
    (1) The microphone should be oriented with respect to the vehicle being
        measured in accordance  with the instructions or recommendations
        of the microphone manufacturer for optimum flat frequency response.
    (2) To minimize the  influence of the observer on the measurements,  no
        person  should be positioned  within 10 feet of the microphone nor
        between the vehicle and the microphone.
    (3) All noise measurements  should be made with A-weighting and the fast
        meter response of the sound level meter.
                                    78

-------
(4)  The background noise at the site (namely, the noise level measured
    with A-weighting and fast meter response due to all other sources of
    noise except the vehicle being measured) should be measured from
    time to time between vehicle passages.  Vehicle noise measurements
    should not be made when the background noise level is within 10 dB of
    the permissible noise standard for the measurement in question.
(!3)  Corrections for measurement at different altitudes above sea-level
    should be made in accordance with the instructions of the microphone
    manufacturer.
(6)  For vehicle pass-by measurements the maximum sound level observed
    as the vehicle passes through the measurement site should be recorded.
(7)  For stationary engine run-up measurements the vehicle engine should
    be accelerated as rapidly as possible from a low idle speed to maximum
    governed speed with wide-open throttle, in neutral gear, and clutch
    engaged.  Measurement of the highest sound level that occurs during
    the engine acceleration should be made at least twice, but more
    measurements should be made if necessary to achieve a satisfactory
    test.
                                79

-------
                      MICROPHONE
                      LOCATION   "*"
Figure A-l. Test site clearance requirements for pass-by test.
                                    VEHICLE
                                    EXHAUST(S)
                                    ON THIS
                                    LINE
                       MICROPHONE/
                       LOCATION
                                                   VEHICLE
                                                   FORE-AFT
                                                   CENTEfiTlNE
Figure A-2. Test site clearance requirements for stationary
            run-up test.
                                 80

-------
12. REFERENCES TO TECHNICAL
        LITERATURE

-------
                             REFERENCES
 1.   Information on Levels of Environmental Noise Requisite to Protect Public
     Health and Welfare with an Adequate Margin of Safety. U.S.  Environmental
     Protection Agency, March 1974.

 2.   Tbid., p.  40.

 :i.   Tbid., pp. B4-5.

 •I.   Kf feels of Noise on People, NTID oOO. 7.

 r>.   Truck Noise I - Peak A - Weighted Sound Levels Due to  Truck Tires,
     N;Uiona] Bureau of Standards Report prepared for Department of Transporta-
     tion, Report No. OST-ONA 71-9, Sept.  1970.

 (i.   Ibid.

 7.   Personal communication with W. H. Close, Department of Transportation.

 H.   Op. Cit., DOT Report No. OST-ONA 71-9, p. 3-4.

 9.   "Transportation Noise and Noise from  Equipment Powered by Internal
     Combustion Engines," U.S. Environmental Protection Agency, Report NTID
     300.13,  Dec. 31,  1971, p. 94.

10.   Ibid., p.  100.

11.   Ibid., p.  102.

12.   "Diesel Exhaust and Air Intake Noise, " Stemco Manufacturing Company for
     Department of Transportation,  Report  No.  DOT-TSC-OST-73, March 1973.

13.   Ibid.

14.   Data from Service Engine Company, Cicero,  Illinois.

15.   Op. Cit., NTID 300.13,  p. 103.

16.   Ibid., p.  102.

-------
17.  Wvlo  l,.ilx>r:ilorics, prrson.il eommuimulion wilh l'losc-A-Lite Corporation,
    T.icomn, Washington.

is.  VVyle Laboratories, personal communication with Advanced Products Group,
    White Motor Company, Torrance, California.

19.  Shipe,  M.D.,  "Operating Principles of the Schwitzer Viscous Fan Drive,"
    Schwitzer Division of the Wallace-Murray Corp., Indianapolis,  Indiana,
    March 1971.

20.  Op. Cit., NTID 300.13, p.  103.

21.  Published literature from Schwitzer Division of the Wallace-Murray Corpo-
    r:ilLon, Indianapolis, Indiana.

22.  Op. Cit., NTID 300.13, p.  104.

2:i.  Tbid., p. 102.

24.  Ibid., p. 104.

25.  Luw,  R. M., "Diesel Engine and Highway Truck Noise Reduction," Society
    of Automotive  Engineers (SAE) Report 730240, Jan. 1973.

2fi.  Op. Cit., Data from Service Engine Co.

27.  Op. Cit., NTID 300.13, p. 7.

2H.  Ibid.,  p. 103.

2!i.  I.iturature from  Donaldson Company,  Minneapolis, Minnesota.

:»0.  Op. Cit., ODT-TSC-OST-73, March 1973.

:t1.  DiLvisson, J.A.,  "Design and Application of Commercial Type Tires,"
    SAE Paper SP 344, Jan. 1969.

:t2.  Wik,  T. R., and  Miller, R. F., "Mechanisms of  Tire Sound Generation, "
    SAE Paper SP 373, Oct. 1972.

33.  Wyle  Laboratories personal communication with major tire companies.

34.  Op. Cit., DOT Report OST-ONA 71-9.

35.  Ibid.,  p. 42.

36.  Ibid.,  p. 44.

-------
37. Ibid., p. 42.

38. Op. Cit.,  Data from Service Engine Co.

39. Op. Cit.,  NTID 300.13, p. 92-95.

40. Close, W. H., and Atkinson, T., "Technical Basis for Motor Carrier and
    Railroad Noise Regulations," Sound and Vibration,  Vol. 7, No. 10,
    Oct. 1973.

-11. Op. CH., NTID 300.13, p. 92-93.

42. "Community Noise," U.S. Environmental Protection Agency, Report NTID
    300.3, Dec^ 31,  1971,  pp A-5,  A-7.

43. Ibid., p. 4.

'14. Op. Cit.,  NTID 300. 3,  pp. A-5, A-7.

4f>. Ibid., p. 5.

•Hi. You UK,  H. W., "Single  Number Criteria for Room Noise," JASA, 36, 2,
    Feb. 1904, p. 289.

47. Klumpp, R.G., and Webster, J, C., "Physical Measurement of Equal Speech
    Interfering Navy Noises," JASA, 35, Sept.  1963, p. 1328.

48. Wells, R. J., "A New  Method for Computing the Annoyance of Steady State
    Noise versus Perceived Noise Level and Other Subjective Measures," JASA,
    46, July 1969, p.  85.

49. Webster, J. C., "Affects of Noise  on Speech Intelligibility," Proceedings of
    Conference, Noise as a Public Health Hazard, Washington, D. C., June 1969,
    AS1IA Report #4.

50. Op. Cit.,  NTID 300.13, p. 94.

51. "Research on Highway  Noise Measurement Sites,"  Wyle Laboratories  Report
    for California Highway  Patrol, March 1972.

52. "Use of Motor Vehicle  Noise Measuring Instruments," California Highway
    Patrol Report, 1965.

53. "California's Experience in Vehicle Noise Enforcement," California Highway
    Patrol Report, 1965.

54. Foss, R. N.,  "Vehicle Noise Study - Final  Report," Applied Physics Labora-
    tory, University of Washington,  Report for Washington State  Highway Commis-
    sion, Department of Highway, June 1972.

-------
55.  Unpublished data, Bolt, Beranek and Newman.

56.  Op. Cit.,  "Use of Motor Vehicle Noise Measuring Instruments".

57.  Op. Cit.,  Exhibit G., (ONAC Docket M070).

58.  Op. Cit.,  "Vehicle Noise Study  - Final Report".

59.  Op. Cit.,  Unpublished Data, Bolt, Beranek and Newman.

60.  1972 Census of Transportation - Truck Inventory and Use Survey,
    U.S. Department of Commerce, Bureau of the Census.

Gl.  Ibid.

62.  American Trucking  Trends, 1972,  by the American Trucking Associa-
    tion, Inc., Washington, D. C.

63.  "1973 Motor Truck Facts, " by the Motor Vehicle Manufacturer Associa-
    tion, Detroit,  Michigan.

64.  Response from American Trucking Association,  (ONAC Docket MOSS).

65.  Op. Cit.,  1972 Census of Transportation Truck Inventory and Use Survey.

(!(i.  Op. Cit.,  American Trucking Trends.

67.  ()p. Cit.,  Literature from Donaldson Company.

6H.  Wyle Laboratories  communication with the Schwitzer Division of Wallace-
    Murray Corporation and the Flcx-a-lite Corporation,  1973.

69.  Bolt,  Beranek and Newman,  Inc. ,  Report No.  2563, "The Cost of Quieting
    Heavy Cab-Over-Engine Diesel  Tractors," July  1973.

70.  Op. Cit.,  Wyle Laboratories personal communication with 3 major muffler
    manufacturers.

71.  Op. Cit.,  NTID 300.7.

72.  Study conducted by Bolt, Beranek and Newman, Inc.

73.  Maryland Department of Transportation submission to the Docket.

-------
                           Reprinted  by  Permission of
                           Sound  and  Vibration  Magazine
Technical   Basis   for   Motor   Carrier
and   Railroad   Noise   Regulations
William  H. Close and Thomas Atkinson, U.S.  Department of Transportation, Washington,  D.C.
  Technical considerations behind the  interstate motor
carrier and railroad  noise regulations proposed by the
Environmental Protection Agency are reviewed in light
of the EPA task force findings and subsequent analysis
by the authors.

  As of this writing the  first decisions have been made
regarding  the Federal regulation  of noise generated  by
motor carrier and railroad operations which are subject
to the provisions of the Noise Control Act of 1972. The
following  is a brief discussion and analysis of the tech-
nical information developed by the interagency task forces
and public docket which  was made available to the EPA
for development of their regulatory strategy.
  It  should be noted that the Department of Transporta-
tion  personnel worked particularly closely with EPA in
these task  force  endeavors since  the Noise Control Act
stipulates that DOT enforce the noise emission standards
promulgated by EPA for motor carrier and railroad opera-
tions. Many of the facets  of the EPA noise emission stan-
dards are appropriately drawn to facilitate enforcement,
but until DOT enforcement regulations  are promulgated
(target date October 1974) a complete package of Federal
standards  will not be available for state  and local emula-
tion  as provided for in the Act.

Interstate Motor Carrier Operations
  A  good body of data exists on the character of noise
generated by interstate motor carriers. Good, albeit local-
ized  experience has been gained in the enforcement of
motor vehicle noise regulations, and substantive research
is underway to ascertain the technology and cost involved
to significantly  lower the engine-related and tire noise
generated by trucks.
   Data provided by vehicle manufacturers on specific  ve-
hicle noise generation,1 roadside survey data from Cali-
fornia,2 Washington State,3 and New York 4 plus research
findings of a number  of DOT contracts  5'13 provided  the
bases for the characterization  of noise generated by inter-
state motor carriers and delineate the norms of reasonably
good practice in  operation and maintenance insofar as
noise is concerned. It is evident that engine-related noise
and tire noise are distinctly different, responding differently
to vehicle operational variables, and are amenable to dif-
fering degrees of noise reduction involving different  in-
dustries. On the other hand, it is total vehicle noise which
must be controlled in order to improve the acoustic  en-
vironment  of roadside communities. The technical data
assembled for the EPA noise  emission standards decisions
accordingly centered on  the  total vehicle noise at road-
side  locations and on the separate vehicle  sources and
driver techniques wherever  special considerations were
appropriate.
Figure 1 — Truck population noise  levels at  low  speeds.
                    (v ^ 35)
Figure 2 — Truck  population  noise level at  high speed.
                    (v > 35)

  The three  roadside  surveys2'3'4 provided substantive
statistics for typical truck population  noise levels at low
speeds (Figure  1) where tire noise is  not a significant
factor, and for highway speeds (Figure 2) where tires are
frequently the dominant source of noise. For speeds less
than 35 mph, the samples tend to indicate that the active
new vehicle and vehicle-in-use noise enforcement program
in California has reaped a substantial benefit over the un-
controlled population of  vehicles which may be repre-

                      Sound and Vibration • October 1973

-------
   1-
   i
Figure 3 — Comparison of stationary  runup and vehicle ac-
              celeration  (J366a) test  results.

sented by the New York sample. (Note that New York
State was the first  to  impose  objective statewide  noise
level limits, but enforcement of numerical limits has been
minimal.) Washington State, which  has no motor  vehicle
noise limit regulations, apparently is benefitting from the
active enforcement  program in  California,  many  miles
away but linked by the many interstate trucks which must
meet the  California  noise limits.
  The high speed data (Figure 2) again shows New York
State to possess the noisier trucks, but no difference ap-
pears  between  California and Washington  truck  noise
levels. At the higher speeds encompassed by these data,
tire  noise becomes a significant if not the dominant fac-
tor.  Since these samples are not weighted according to
actual vehicle speed and since tire noise is a direct func-
tion of vehicle speed (for a given tire type, vehicle weight,
number of tires  and road surface) 5'6'7 one cannot a priori
assess the full implications of these data. One can, how-
ever, say that normal practice  results  in the distribution
of noise levels indicated. (Caution  must be exercised in
interpreting such  independent  surveys since bias  errors
of say 2 dB could collapse all of the  data to essentially
one  curve.) If one  then selected some  cut-off  level for
the  regulation,  a  given  percentage  of trucks would  be
found to be in violation and the  remainder of the popu-
lation would verify the existence of sufficient technology,
etc., to comply. One cannot, however, say with any as-
surance that  a  simple fix would bring all  vehicles into
compliance or that all vehicles can be brought into com-
pliance regardless of expense.
  Another basis for decision exists in the voluntary stan-
dard set in 1954  by the Automobile  Manufacturers As-
sociation (now known as the Motor Vehicle Manufacturers
Association) for all  new trucks. This  standard  calls for
a maximum loudness of  125 Sones.  In 1968, the Society
of Automotive Engineers re-studied  this  standard and  is-
sued a similar 125 Sone maximum loudness Recommended
Practice (J672a)14 and  another  Recommended Practice
using the simpler A-weighted sound  level with an equiva-
lent 88  dB(A)  maximum  recommended level  (J366a).15
Since these  three  documents have been subscribed to  by
the  truck building industry for a period of time encom-
passing the  manufacture of virtually all  the trucks  oper-
ating today, one  can safely  say that such a  maximum
noise level represents the standard of practice. The prob-
Figure 4 — Engine related and  tire noise, 50 feet from lane
       of travel for a typical 18 wheel tractor-trailer.

lem then is  to relate this standard of practice to the noise
levels  generated in service, and to prepare  enforceable
regulations.
  This  was  accomplished  by  the task force as follows.
Low speed  truck noise should be somewhat less than the
maximum noise level  of the AMA and  SAE statements.
Two decibels less was determined  to be reasonably lower
and had been found to be enforceable by the California
Highway Patrol.2 Six percent of the California  population
of trucks and eighteen percent of  the  New York popula-
tion of  trucks would be out of compliance at this level —
many of which could be assumed in need of exhaust sys-
tem maintenance. DOT  research projects completed but
not yet reported in the literature clearly illustrate the com-
mercial availability  of exhaust  and intake mufflers which
will  adequately reduce these  two  noise  sources  to low
enough levels to meet  the  proposed 86 dB(A)  at  50 feet
low speed  operational level.  These same studies,  how-
ever,  indicate that  although naturally  aspirated engines
require such exhaust mufflers  (costing between $30 and
$50 each) some  turbocharged engines can comply without
an exhaust  muffler.  Thus,  appropriate  equipment  provi-
sions  have been  proposed as guidance for operators and
as easily enforceable provisions requiring no sound mea-
surement equipment.
  Another section that has been proposed relates directly
to the manufacturer standards; this is a stationary engine
run up test for  vehicles powered by governed  engines.
Some pilot testing of this noise measuring technique is re-
ported in reference 8,  but the  statistically significant veri-
fication of the  approach has been provided  by the SAE
Vehicle Sound Level  Committee as shown  in Figure  3.
Such  a  test  will be quite useful for enforcement at weigh
stations, for example, for us  at state  inspection stations
and conceivably  for use  by the fleet owner  to check his
vehicle.
  The final  aspect of the low  speed noise regulation pro-
posed  is oriented toward the  truck  driver.  This facet  of
the regulation requires the  driver of an in-compliance ve-
Sound and Vibration • October 1973
                                                                                                                 29

-------
hicle to operate his vehicle in a quiet fashion when he is
not  on an expected truck route.  California survey data2
show that an 80 dB(A)  level at 50 feet will be exceeded
by five percent of trucks on level streets. While California
has  adopted an  82 dB(A) level  in their  regulations,  the
lower level was  selected by EPA with appropriate cave-
ates for grade, street type, distance from traffic signals and
traffic conditions such  that  the percentage  of vehicles
expected  to be in violation would be the same as for  the
unrestrained low speed  regulations.
   The high speed regulations were  proposed taking into
account the fact  that engine related noises do not increase
with vehicle  speed but are  a function  of engine speed
only. Thus, the vehicle  noise  increases from idle  to near
maximum and fluctuates up and  down by a few decibels
as the vehicle is accelerated  through the various gears.
(Engine speed varies through a typical range of 1700 to
2100 rpm for each gear.) As the vehicle speed  increases,
tire  noise increases as a continuous function  of  vehicle
speed as shown on Figure 4 for a typical 18-wheel  tractor
trailer. Significant differences  exist between the  sound
levels generated  by suction-cup  retread,  cross-bar tread,
and rib tread tires as shown. Tire use surveys by the Rub-
ber  Manufacturers Association1B and Stevens Institute1T
for DOT  show that slightly less than half the truck popu-
lation is equipped  with  cross-bar tires on the drive axles,
virtually all trucks are equipped with rib tires on the front
or steering axle,  and that rib tires predominate the usage
on trailer axles although suction cup treads and well-worn
cross bars are frequently used  on trailer axles  as well.
An  informal survey by  the American Trucking Associa-
tions 18 and  an interesting  study by the Western High-
way  Institute 1D  confirm these general tire  use  practices.
A special subset of the Stevens  and RMA data was  ex-
amined to look more closely at the tractor drive axle tire
usage. This indicated that up to  two-thirds of this popu-
lation used cross bar tires on drive axles. The typical tire
noise situation is, therefore,  best  represented by the mid-
dle  tire noise curves of  Figure 4.
   Tire noise  research findings documented by  DOT8-6
and  General  Motors20  provide a good parametric  pic-
ture  of  truck tire  noise variables  for  a representative
selection  of commercial  truck tires. The Society of Auto-
motive Engineers has developed a  truck  tire noise test
procedure (Recommended  Practice  J57)  which  specifies
a truck coast-by  with four test tires  on the rear axle and
rib or quiet  tires on the steering axle  (as per the DOT
and  CM procedures).  The SAE selected smooth  concrete
and  50 mph speed as the standard test  conditions.  The
tester is responsible for determining the noisiest condition
of normal tire wear for the tests and reporting the result
and  level for the particular tire type.  To relate such tests
to typical roadside noise levels at 60 mph  (tires plus 86
dB(A) engine-related noise) we have constructed Table I.7
This indicates the expected sound level for various truck
configurations using half-worn rib tires  on  trailer  and
steering axles and half-worn tires of various types on the
drive axles.  The 50 mph coast-by sound  level  of four
tires of the type used on the drive axle is  indicated across
the top line and  the full configuration sound levels at 60
mph and  appropriate (sometimes lower) axle loadings are
shown in the columns below. The high  speed  roadside
noise surveys have  shown  that a relatively wide  range of
noise levels  are generated. Hence,  the choice as to which
level should be set  for the  regulations  was based upon the
precedent of the existing regulations in  California  and
other states  taking into  account  the statistical  data as
well as the deterministic  tire and engine noise  data. A
level of 90 dB(A) at 50 feet to the side of the centerline
of the lane  of travel was thus selected.  Some 12 to 16
percent of California and Washington vehicles and up to
33 percent of New York vehicles  would  be in violation.
From Table  1 it can be seen that this implies drive  axle
use of tires  with  certification  levels of 82  dB(A)  or lower
for most truck configurations  to comply with this portion
of the regulation.
  Such high speed  noise standards obviously outlaw the
use of the suction  cup retreads (hence, visual inspection
for such tires is  included  in  the standard) and limit the
use of cross-bar tires  To  date, despite claims by manu-
facturers  and users alike,  no real tractor  or economic
benefit has been found for highway use of cross-bar tires.
Off-road and possibly snow conditions may be better  met
with cross-bar tires, but even if this is  proven to be im-
portant the  limited  occurrence of  such conditions seems
to be outweighed by the mandate for noise reduction on
the highway. Perhaps improved tires  will now be devel-
oped which can provide clear advantages to specialty users
yet meet the noise  level limits of  the  use  regulations  and
possible future new product regulations  by states  and the
EPA.

Interstate Railroads
  While various  community  noise surveys  indicate that
                Table 1 — Effects of tire noise certification levels @ 50 feet on passby sound levels ® SO feet.


Truck
Config.
Gross Wt.
Certification
Limit
78 dB(A)
80 dB(A)
82 dB(A)
84 dB(A)
86 dB(A)
90 dB(A)
95 dB(A)


4X2
Straight
27k*



6X4
Straight
45k*

4X2
Single
Axle
Trailer
45k#

4X2
Double
Axle
Trailer
59k#


4X2
Double
Bottom
73k*

6X4
Double
Axle
Trailer
73k*


6X4
Double
Bottom
73k*

50 Feet Passby Sound Level, dB(A)
88.0
87.5
88.8
90.8
89.9
94.8
98.3
89.0
88.4
90.3
93.0
91.7
96.7
101.2
88.5
88.2
89.3
91.1
92.1
95.4
98.6
88.8
88.5
89.6
91.3
91.8
95.0
100.4
89.0
88.9
89.5
90.8
91.5
94.3
101.8
89.4
88.9
90.1
92.2
92.4
96.4
100.5
89.4
89.1
89.1
90.2
91.4
94.0
101.7
30
                                                                                     Sound and Vibration • October 1973

-------
noise from railroad  operations does not constitute a wide
spread source of community annoyance, certain operations
do constitute a source of localized annoyance,  and have
precipitated  numerous local ordinances. Most importantly
the Congress has directed EPA and DOT to regulate this
noise. Since  the railroad noise problems are not as exten-
sive nor as  intensive as  a number of other sources, the
body of information in the literature is  quite  sparse  as
evidenced in two recent Government literature surveys.21-22
The task force approach  was again  taken by EPA  to
evolve a basis for the mandated  noise regulations but  in
this case the EPA has made the determination that suf-
ficient data  were  not made  available to issue  proposed
regulations by the July  date specified in  the Noise Con-
trol Act. What data were  developed,  however, are sum-
marized  below.
   Due to the  lack of data in the open literature and  in
light of the keen desire of the railroads to attain a degree
of standardization  in the regulations with which they must
comply, the  task force sought and received a high degree
of cooperation from many railroads  and the two major
locomotive builders through  the  good offices of the As-
sociation  of  American  Railroads  (AAR).  Specifically,   a
number  of  railroads (too many to reference here) con-
tributed for  task force use, copies of reports  from numer-
ous small noise studies made on their properties and pro-
vided a large volume of statistical information  regarding
right-of-way, yards,  motive  power,  rolling stock,  fixed
facilities, etc. (A summary of this information  was sub-
mitted to the docket at EPA.) 23 The  task force  pondered
the  problem and  addressed  the  question of identifying
major noise  sources and technology available  to control
these sources.  No attempt was made  to  rank the major
sources in  order of priority due  to the paucity of  data.
The major sources identified were: locomotives, rail-wheel
interaction,   whistles and  horns,  classification  yard  re-
tarders, mechanical  refrigerator cars,  and a  potpourri  of
fixed facility noises such as public address systems, main-
tenance  facilities,  piggyback  refrigerator  units, loading
equipment, etc.
   Whistles  and horns  were  determined  to  be  a  major
source of annoyance but were considered to be absolutely
necessary safety appliances  for both  right-of-way opera-
tion and yard operation. Regulation  of this source was,
therefore, considered to be inappropriate but study and
improvement of the grade crossing safety problem con-
tinues to be  a  high  priority matter with the DOT.
   Rail-wheel interaction  noise was recognized  as a per-
vasive source of railroad  noise emissions  but data on the
subject was sparse. Personnel of the DOT Transportation
Systems  Center had acquired some wayside noise data
on high speed passenger  trains and they were ordered into
the field to acquire a body  of conventional passenger and
freight train  wayside data.24 This data now in prepublica-
tion form and other  data supplied through a joint contract
effort by the AAR  and Southern Pacific Railroad 26  were
analyzed by  the coauthor. A typical train passby record-
ing is shown on Figure 5. The maximum noise generated
by the locomotive (exclusive  of horn  or whistle noise)  is
determined as  signified by  line no. 1. An "eyeball"  aver-
age of the rail-wheel noise generated by  the cars (exclu-
sive of the confused areas  immediately behind  the  loco-
motive and the intermediate area  at the end  of  the train)
is  signified by line  no. 3. The upper  and lower bounds
Figure 5 — Graphic  level recording of  a  typical freight train
passby  indicating  sound level  values selected  for  further
analysis: (1) — peak  engine level; (2) — peak car  level; (3) —
         average car level; (4) — minimum car level.
Figure 6 — Peak, average, and minimum rail-wheel sound level
vs. speed for typical railroad cars on welded and bolted  rail.
      Figure 7 — Locomotive population noise level.

are likewise determined as shown by lines 2 and 4. The
peak, average,  and minimum rail-wheel  noise  levels for
freight  and  conventional  passenger trains and  for  high
speed pasenger trains are shown on  Figure 6 for opera-
tions on welded and bolted  rail. The  average points were
weighted by the number of cars  in  the train, but the
maximum and minimum points are plotted as unweighted
absolute values. An average  reduction in rail-wheel noise
levels of up to  3 dB can be observed  as  a result of the
use of  welded  rails. The peak  excursions, however, are
seen to  be inexplicably  higher  in the welded  rail  data
set. The small improvement yielded through use  of welded
rail is more than offset by the huge cost involved in con-
version  of  the 334,000 miles of total trackage in the na-
Sound and Vibration • October 1973
                                                                                                                  31

-------
tion or the 205,000 route miles of track. Such conversion
as is economically beneficial to the railroads  is, of course,
taking place but  a major acceleration of this change-over
or broadening of its  scope could not be justified on the
basis  of noise.  Wheel  maintenance,   of  course,  has  a
major  role to play in this  picture, but insufficient  data
exist to say just  how much.  Safety regulations  now ad-
dress  wheel flats and for safety reasons one may  expect
these  considerations  to  be  made more stringent  in the
future,  but regulations  for  noise purposes  are  not  now
appropriate.
   Diesel locomotive noise as  shown on Figure 7 is  typi-
cally somewhat  higher than  the average rail-wheel noise
level even at  the highest speeds. Note also that median
electric locomotive noise levels are 7 dB lower than diesel
locomotive noise levels  at the measurement distance of
100  feet. Correlation of present locomotive  noise  level
data with  speed  and number  of locomotive levels failed
to show significance but  a relationship seems to exist  with
load as seen in Figure 8. In this representation, a rather
chancy load designation  scheme was used to test for sig-
nificance  of load  without  really  knowing  the  throttle
notch  settings of the  locomotives measured. Nonetheless
a  relationship appears to be  significant when we define
load  as: high (light  weight,  high speed,  up grade or
heavy  weight, low speed,  level or up grade); medium
(light weight,  high speed, level or down grade,  or heavy
weight, high speed, level or down grade); and low (light
weight, low speed or any  grade  or heavy weight,  low
speed  or down grade). The highest sound level recorded
in the data sets was  98  dB(A) at 100  feet  (1.5%  of the
measured population). The median locomotive sound  level
of the data set was 93 dB(A) at 100 feet. (Recall that this
encompasses trains of one  to six  locomotives and  train
speeds  up to  80 mph.)  Proprietary data made  available
to DOT shows that commercially available  earth moving
equipment mufflers (@  $200  to  $300 per muffler, not in-
stalled) will reduce the  noise level of one conventional
freight locomotive  by six dB at 100 feet when operated
at full load on a stationary load box (locomotive generated
electric power dissipated remotely through resistor ele-
ments rather than through  traction motors on the axles).
Thus,  it is presumed  that for all conditions of heavy load
except  for speeds  in excess  of perhaps 60 mph where
locomotive rail wheel noise  may increase the overall  noise
level, 90 dB(A) at 100 feet  would be an achievable level.
The addition  of mufflers would reduce  the low frequency
portions of locomotive noise  which propagates  quite far
into the community and is  especially noticeable at night.
   The noise sources of yard operations are many and are
unpredictable in  terms of diurnal cycling and duration of
any one cycle. To gain some definitive  information on the
subject,  several  members of the task force  met with the
AAR to examine plot plans  and through-put  data  of a
number of railroad yards.  Arrangements were made to
send three measurement teams to several railroad yards to
acquire definitive data.  As  of this writing, the data are
available from only the Kansas City yards of the Atcheson,
Topeka  and Santa Fe Railroad known as the Argentine
Yards.  The Argentine Yards is a massive complex with an
east-bound and  a west-bound classification hump  yard,
engine service facilities  and the full gamut of yard facili-
ties.  Measurements were made during a three  and  one-
half day period along the South property line of the  yard,
at the throats of the  yard, at locations  near  the active re-
Figure 8 — Relationship of locomotive passby noise level with
                  apparent engine load.
    Figure 9 — Railroad yard property line  noise levels.


Figure 10 — Retarder noise levels as a function of distance.
           Insert is typical retarded  noise spectra.

tarders, at locations farther down the classification tracks,
near  the  engine service facilities, and beyond the yard
along the  mainline. A full report  of these data is in pre-
paration for publication this Fall.24  In summary this sur-
vey found the retarders (remotely activated devices which
squeeze the car wheels as  the  cars drift down the hump
gradient)  to be clearly the dominant source of yard noise;
locomotives and mechanical refrigerator cars were the only
 32
                                                                                     Sound and Vibration • October 1973

-------
other sources  reasonably  identified as pervasive noises  in
the yard. The  twenty-minute  samples of  property  line
data were reduced in terms of Lmai, L10, Lso, Lgo, and L«,
as shown in Figure 9.  Large variations in all descriptors
were  noted particularly adjacent to the active retarders
depending upon the level of activity on the hump during
the  sampling  period.  Significant  variations were  also
noted at the throat of the yard and on  the  main line but
some reasonable time integrated descriptor could be used
to regulate total yard  noise if the  retarder  input  were
lowered.
   More definitive measurements made at Argentine Yards,
other data from the literature, past railroad studies and
current AAR/SP research were compared to better assess
the magnitude of the retarder noise problem as shown  in
Figure 10.  Retarder noise is seen to be extremely intense
in level and to have its energy  concentrated in the 2 to 4
kHz bands making the perceived noise  even more annoy-
ing than the  A-weighted levels indicate.  Many  attempts
at lubricating and damping the  retarder shoes have proved
to be unsuccessful  at reducing  the level of the noise  gen-
erated but have tended to reduce the probability of occur-
rence of squeal from a given car when  retarded. At least
one study of a simple barrier has, however, demonstrated
the ability  of a lined  barrier  to  attenuate  the  retarded
sound level  by 20  dB or more.2S  Accordingly  the task
force recommended that  a specific regulation for retarder
noise be set at 100 dB(A) at  100  feet  which  is the
median  sound  level of  the retarder  sound level  data
available to  the task force.  Barrieis  would likely be re-
quired on  all active retarders to ensure that the range  of
emissions would be within  the 100 dB(A) recommenda-
tion.  It was  also  recommended that  mechanical release
devices be installed within a reasonable time on all  inert
retarders (located on each track at the end  of the classifi-
cation to restrain  coasting  cars  from  entering  the main
line)  to permit  strings of cars to be pulled  through these
retarders without squealing. The barrier is  not applicable
to the inert retarders due to space limitations (which may
also limit application  or  effectiveness  on  some  active re-
tarders)  but  the application of manual retractors seems
quite fitting.  Finally,  the  DOT and AAR believed that
joint research efforts could  and should be  undertaken  to
more thoroughly explore  the noise generation mechanisms
and possible  solutions to the retarder noise problem
   The  final area of potential  regulation  appears to  be
mechanical refrigerator cars. Typical levels measured  by
DOT and AAR/SP studies  yield 70-75 dB(A) at 50 feet.
Since these-units are powered  by small diesel engines, it
was felt that muffler technology demonstrated  for trucks
would easily  reduce the dominant exhaust noise by 5 dB
or more and  thus some relief could be afforded residents
at locations where refers are set out and left overnight with
the refrigeration unit running.

Summary
   A  strong  technology base exists for the initial motor
carrier  regulations stemming from past California, indus-
try and DOT efforts. Future revisions  will likely be possi-
ble  as new technology is evolved by  DOT research and
incorporated  into  future production  trucks.  Tire noise
appears to be the  toughest problem to be faced in motor
carrier  regulations.  Railroad noise regulations have  been
deferred  pending  better   resolution   of  the   problem.
 Demonstrations of noise reduction fixes by AAR and DOT
are planned  to proceed as rapidly  as  possible to resolve
such questions.

References
 1. Various manufacturers submissions to the Environmental
    Protection Agency Advanced Notice of  Proposed  Rule
    Making,  Motor Carrier Noise  Emission Standards Docket
    No  ONAC 7202001.
 2  Anon., "Noise  Survey of Vehicles Operating on California
    Highways," by the Department  of  California  Highway
    Patrol, 1971,  Sacramento,  California
 3  Foss, Rene N., "Vehicle Noise Study—Final Report," pre-
    pared  for Washington  State Highway Commission, De-
    partment of  Highways, 30 June  1972.
 4  New York State Department of Environmental Conserva-
    tion Comments on  Advanced Notice of  Proposed  Rule
    Making,  Motor Carrier Noise  Emission Standards Docket
    No  ONAC 7202001.
 5  Anon , "Truck  Noise I—Peak A-Wcighted Sound Levels
    Due to Truck Tires,"  DOT Report OST-ONA-71-9, Sep-
    tember 1970, Washington, DC
 6. Leasure,  W.  A, et al., "Truck Noise  I—Peak A-Weighted
    Sound Levels Due to Truck Tires, DOT Report OST/TST-
    72-1, Addendum, July 1972
 7  Close, \V H. and Leasure, W , "Truck Noise I-A" to  be
    published
 8. Close, W H  and Clarke, R , "Truck Noise II—Interior
    and Exterior A-Weighted Sound  Levels of Typical High-
    way Trucks,"  DOT Report OST/TST-72-2
 9. Unpublished  results of DOT contract with Freightliner
    Corporation, Contract  No  DOT-OS-20095
10  Unpublished results of DOT contract with White  Motor
    Company, Contract No  DOT-OS-20221
11  Unpublished results of DOT  contract with  International
    Harvester, Contract No. DOT-OS-20222.
12 Unpublished  results  of DOT contract  with  Donaldson
    Company, Inc, Contract  No.  DOT-TSC-532
13. Unpublished results of DOT contract with Stemco Manu-
    facturing Company, Contract  No DOT-TSC-73-12.
14 Society  of  Automotive Engmecis,  Inc., Recommended
    Practice  J672a, Exterior  Loudness Evaluation of Heavy
    Trucks and Buses, SAE 1971,  New York,  NY.
15 Society  of Automotive Engineers,  Inc., Recommended
    Practice  J366a, Exterior Sound  Level for Heavy Trucks
    and Buses, SAE, 1971, New York, NY.
16 Rubber Manufacturers Association, Thmway Truck Noise
    Test, October 1964.
17. Ehrlich,  J R.  et al, "A Truck and Bus Tire Use Pattern
    Study,"  Stevens  Institute Report No.  SIT-DL-71-1573,
    December 1971
18. Private communications with  Larry  Strawhom,  American
    Trucking Associations.
19 Western  Highway Institute, "Tire Wear Characteristics of
    Trucks and Truck Combinations," July 1, 1971.
20. Tetlow, Derek, "Truck Tire Noise," Sound and Vibration,
    Vol 5, No. 8, August 1971, pages 17-23
21. Serendipity,  Inc., "A  Study of the Magnitude of Trans-
    portation Noise Generation  and  Potential  Abatement—
    Vol. 5—Tram/Railway Systems," Report No. OST-ONA-
    71-1,  Nov. 1970.
22. Environmental  Protection  Agency, "Transportation Noise
    and Noise from Equipment Powered by Internal  Combus-
    tion Engines," NTID300.73, December 1971.
23 Association of American Railroads comments on  Environ-
    mental Protection Agency Advanced  Notice of  Proposed
    Rule Making—Railroad Noise Emission Standards, Docket
    ONAC 7201001.
24 Rickley,  E, et al, "Railroad,  Freight Yard and  Wayside
    Passenger Line Haul for Noise  Level Measurements," to
    be published
25. Kurze, Ulnch  J.,  et  al,  "An  Investigation of  Potential
    Measures for the Control  of Car Retarder  Screech Noise,"
    Bolt, Beranek,  &  Newman, Inc.,  Report  No. 2143,  Apnl
    1971.
26. Anon., "Community  Noise Profiles for Typical  Railroad
    Operations," Preliminary  Data From Wyle Laboratories
    Research Project No. 59141, May 15, 1973.
 Sound and Vibration • October 1973

-------
                               Reprinted by Permission of
                               Commercial  Car  Journal
                   Everyone knows that aa trucks gat old, thay become
                 tired and noiay. Yet, federal lawa that take effect thia fall
                   threaten to take many In-service trucka off the road
                     unlaaa thay can ba mada qulat Recent taatlng at
                    Schwltxar confirms that turbochargara halp muffle
                   exhaust nolaa and add pap to oldar engines aa wall.
                        It'a Ilka having your caka and eating It too.
    PUTTING  ft
                          ON  TRUCK
    •  FOR YEARS, engine manufacturers and fleet op-
    erators have  employed  turbocharging  to boost
    diesel engine efficiency and power output at rela-
    tively low cost Essentially an exhaust-driven cen-
    trifugal compressor, the turbocharger delivers
    more air to the engine's cylinders than is possible
    with natural aspiration The increased air/fuel ra-
    tio results  in  more thorough and gradual com-
    bustion, producing greater horsepower  and  less
    smoke In addition, improvements of 5 to 10% in
    specific fuel consumption are also possible
      Now another feature of the turbocharger  is
    likely  to become  important  to the  trucking in-
    dustry—its ability  to reduce exhaust noise. Recent
    testing at Schwitzer Division of Wallace Murray
    Corp  indicates retrofit  of turbocharger kits on
    naturally aspirated diesel engines can significantly
    reduce truck noise levels  This  is  particularly
    noteworthy in light of U S Environmental Protec-
    tion Agency  noise emission regulations for in-
    service heavy-duty diesel trucks which take effect
    October 15 of this  year.
      The new federal truck noise maximums are
    • 86 db(A) at 50 ft at speeds up to 35 mph
    • 90 db(A) at 50 ft at speeds greater than 35 mph
    • 88 db(A) at 50 ft for stationary tests
      The test program, conducted  by  Schwitzer's
    Advanced Technology  Group, involved an in-
    service 1968 White-Freightliner tandem  axle  trac-
    tor powered by a Cummins NHC-250 engine In-
    itial checks of the truck in its received  condition
    registered a respectable 87 6 db(A) noise level, in-
    dicating it had been well maintained
       By installing a Schwitzer model 4LF turbochar-
    ger plus a standard "quiet"  muffler, the group's
    engineers were able to reduce exhaust noise to the
    neighborhood of 83 db(A)—well below the feder-
    al maxim urns

    Drive-by tMte
       Tests were run  on five different configurations
    as shown in figure 1  For each configuration, two
Test Configuration Turbocharger     Exhaust'
1 (received condition)   no
2                 no
3                 no
4                 yes
5                 yes
conventional muffler
straight pipe (no muffler)
"quiet" muffler
straight pipe
"quiet" muffler
'Note ground-to-exhaust distance was maintained throughout
the test, however, exhaust pipe diameter was increased from 4-m
to 5-in after turbocharger installation

Figure 1	^^^_

types of exterior noise tests were conducted  the
SAE J-366b acceleration drive-by test, and a sta-
tionary engine acceleration  test  Results of  the
SAE drive-by tests are shown in figure 2. As  the
graph illustrates, the  turbocharger alone (con-
figuration 4) cut 86 decibels from the  truck's  un-
muffled exhaust noise level of 98 5 db(A)
  Figure 2 also  shows that  retrofit of a muffler
specifically recommended  for the  Cummins
NHC-250  reduced the truck's noise 2.7 decibels
from its original  in-service  level of 876 db(A)
The choice of muffler was based on information
obtained from a  1973 U S Department of Trans-
portation compilation of muffler manufacturers'
data and muffler recommendations for given  en-
gine models
  Although retrofit of the "quiet" muffler alone
reduced the vehicle's  noise  below the proposed
federal maximums, the lowest sound level pro-
duced in the drive-by tests resulted from the com-
bination of the  turbo with  the "quiet" muffler
(configuration 5) A total reduction of 4 9 db(A)
from the  original truck configuration  was  ob-
tained with this combination

Stationary tests
   The stationary exterior  noise test used  by
Schwitzer bears close relationship to  the results
obtained from the SAE drive-by test. The site set-
up for the stationary test was  identical  to  that
                                  Continued
1M COMMERCIAL CAR JOURNAL Feb 1975

-------
Top left: The turbocharger, an exhaust-powered centrifu-
gal compressor bolts to a dlesel engine to improve power
and fuel  economy while reducing smoke ...  and now,
noise. Top right: Schwltzer model 4LF turbocharger as in-
stalled on test vehicle. Engine is Cummins NHC-250.
Above left: The test truck, a 1968 White-Freightliner. was
exceptionally well maintained, registering an overall noise
level of only 87.6 db(A) as received.
Above right: Without muffler, test truck measured 98.5
db(A). This was reduced to 82.7 db(A) after installation of
turbocharger and "quiet"  muffler specifically  recom-
mended for an NHC-250.
                                                                               COMMERCIAL CAR JOURNAL Fob 1975  107

-------
TURBO"
     used for the SAE drive-by test,  and DOT noise
     test specifications were used as a guide. The test
     was conducted with the vehicle parked in the cen-
     ter of the test path with its exhaust located oppo-
                       dB(A)
   NATURALLY ASPIRATED CONVENTIONAL MUFFLER
   NATURAtlV AbPIHAffcD NO MUFFLtH
                                         87.6
                                                  985
                       Figure 2
               Comparison of Noise Levels. dB (A)
                 As Measured by SAE J-366 b
                     DRIVE-BY TEST


                       dB(A)

                60       70       80
   NATURAllY ASPIRATED CONVENTIONAL MUFFLER
   NATURALLY ASPIRATED NO MUFFLER
                                                    989
   NATURAUV ASPIRATED QUIET MUfFLER
   TUflBOCHARGED NO MUFFLER
   TURBOCHARGEO QUIET MUFFLER
                                            902
                       Rgure 3
                Comparison of Noise Levels, dB (A)
           As Measured by Stationary Engine Acceleration Test
site the microphone. Engine noise was measured
as the engine was abruptly accelerated from low
idle to 2350 rpm, its governed maximum.
   Figure 3 shows the results. On the average, the
stationary  trials  produced sound levels approxi-
mately  half a  decibel lower than for the  corre-
sponding  SAE drive-by test. Retrofit of both the
"quiet" muffler and the turbocharger reduced the
decibel level  to 81.5 db(A), a 5.2  decibel  drop
from  the  original  in-service  configuration. And
once  again, turbocharging alone accounted  for a
substantial 8.7 decibel noise reduction from the
no-muffler configuration.
   Commenting on  the test results, Max E.  Rum-
baugh,  Schwitzer's Advanced Technology Group
Project  Manager, told CCJ that  because  the test
vehicle  had been exceptionally  well maintained
from  a noise standpoint, it would be "unrealistic"
to assume  "quiet"  mufflers would  reduce noise
levels below the federal  maximums for every in-
service heavy-duty truck.
   The  turbocharger,  however, used in  con-
junction with  today's state-of-the-art muffling
techniques appears to provide  the margin neces-
sary to meet  regulations that take effect  this fall
and, perhaps, progressively stricter noise laws like-
ly to be enacted after that.               D  D D
                       Fig.4
                                                         Figure 4. Diagram shows dimensions of standard SAE J-
                                                         366b drive-by noise test site. Same site was used for sta-
                                                         tionary testing with vehicle parked in center of drive-by
                                                         path.
                                                             For a free single copy of this article, write on
                                                             company  letterhead  to: Editor, Commercial
                                                             Car Journal, Chilton Way, Radnor, Pa 19089
108  COMMERCIAL CAR JOURNAL Feb 1975

-------
13. FEDERAL. STATE, AND LOCAL
         AGENCIES

-------
           I N D E X
U.S. ENVIRONMENTAL PROTECTION AGENCY
AMD DEPARTMENT OF TRANSPORTATION
REGIONAL OFFICES
U.S. DEPARTMENT OF TRANSPORTATION
BUREAU OF MOTOR CARRIER SAFETY
INVESTIGATORS WITHIN EACH REGION
LIST OF STATE AND LOCAL NOISE PROGRAMS

-------
U.S. ENVIRONMENTAL PROTECTION AGENCY
AND DEPARTMENT OF TRANSPORTATION
REGIONAL OFFICES

-------
                                  SECTION 13

                   FEDERAL, STATE, AND LOCAL AGENCIES


Region 1 States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont
     USEPA                                DOT/BMCS
     Room 2113                             4 Normanskill Blvd.
     JFK Federal Building                     Delmar, New York  12054
     Boston, Mass.  02203

Region 2 States: New Jersey, New York
     USEPA                                DOT/BMCS
     Room 9076                             4 Normanskill Blvd.
     26 Federal Plaza                         Delmar, New York  12054
     New York, N.Y. 10007

Region 3 States: Delaware, Maryland, Pennsylvania, Virginia, West Virginia, District of
               Columbia
     USEPA                                 DOT/BMCS
     Room 225                              Room 816-A
     Curtis Building                          Federal Building
     6th and Walnut Streets                    31 Hopkins Plaza
     Philadelphia, PA 19106                   Baltimore, MD  21201

Region 4 States:  Alabama, Georgia, Florida, Mississippi, North Carolina, South Carolina,
               Tennessee, Kentucky
     USEPA                                 DOT/BMCS
     Room 109                              Suite 200
     1421 Peachtree Street                     1720 Pcachtree Road, N.W.
     Atlanta, GA 30309                       Atlanta, GA 30309

Region 5 States:  Illinois, Indiana, Ohio, Michigan, Wisconsin. Minnesota
     USEPA                                 DOT/BMCS
     203 South Dearborn Street                 18209 South Dixie Highway
    Chicago, ILL 60604                      Homewood, ILL 60430
                                    13-1

-------
Region 6 States: Arkansas, Louisiana, Oklahoma, Texas, New Mexico
    USEPA                                 DOT/BMCS
    Room 1107                             819 Taylor Street
    1600 Patterson Street                    Fort Worth, Texas 76102
    Dallas, Texas 75201

Region 7 States: Iowa, Kansas, Missouri, Nebraska
    USEPA                                 DOT/BMCS
    1735 Baltimore Street                    P.O. Box 7186
    Kansas City, MO  64108                  Country Club Station
                                           Kansas City, MO  64113

Region 8 States: Colorado, Utah, Wyoming, Montana, North Dakota, South Dakota
    USEPA                                 DOT/BMCS
    Suite 900                               Room 151,  Building 40
    1860 Lincoln Street                      Denver Federal Center
    Denver, Colorado 80203                  Denver, Colorado 80225

Region 9 States: Arizona, California, Nevado, Hawaii
    USEPA                                 DOT/BMCS
    100 California Street                     450 Golden Gate  Ave.
    San Francisco, Calif.  94111               Box 36096
                                           San Francisco, Calif.  94102

Region 10 States: Alaska, Idaho, Oregon, Washington
    USEPA                                 DOT/BMCS
    Room lie                              Room 412,  Mohawk Bldg.
    1200 Sixth Ave.                         222 S.W. Morrison St.
    Seattle, Wash. 98101                     Portland, Oregon  97204
                                     13-2

-------
                   U.S. DEPARTMENT OF TRANSPORTATION
                    BUREAU OF MOTOR CARRIER SAFETY
                    INVESTIGATORS WITHIN EACH REGION
*Region 1 - Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York,
           Rhode Island, and Vermont
Russell G. Toth - DRMCSO
Leo W. O'Brien Federal Bldg., Rm. 720
Albany, New York  12207
AC 518-472-7866 or 7866, Com. Same
SAFETY INVESTIGA TORS

James Bowler
John F. Leary, Richard A. Gosselin
990 Wethersfield Avenue
Hartford, Connecticut 06114
Tel. 203-244-2036, Com. Same

Richard Basanko
Federal Building & U.S. Post Office
Room 614,40 Western Avenue
Augusta, Maine 04330
Tel. 207-622-6262

Gerald M. O'Brien, Matthew Pratt
P. Joseph Gibbons
John F. Kennedy Federal Bldg., Rm. 612-B
Boston, Massachusetts 02203
Tel. 617-223-7281

Robert B. Gallant
55 Pleasant Street
Concord, New  Hampshire 03301
Tel. 603-224-7720, Com. 603-224-3385

Edward A brams
William P. Jensen
25 Scotch Road, 2nd Floor
Trenton, New Jersey 08628
Tel. 609-599-3641, Com. 609-599-3511 ext. 41

*Conforms to Standard Federal Regions 1 and 2
Raymond Valentine - RHMS
Ralph E. Johnson - RAIS
Leo W. O'Brien Federal Bldg., Rm. 720
Albany, New York 12207
AC 518-472-7866 or 7509, Com. Same
Frederick J. Grum, Jr.
614 Federal Office Bldg.
111 Huron Street
Buffalo, New York 14202
Tel. 716-842-2136

John P. Goodwin, John Whalan
William L. Taylor, Jack Takekjian
John C. Goodwin, George R. Cowan
Leo Smith
U.S. Custom Court & Federal Office Bldg.
26 Federal Plaza, Rm. 1800
New York, New York 10007
Tel. 212-264-1070 or 1080

Roben C. Beardsley
Midtown Plaza, Rm.  204
700 E. Water Street
Syracuse, New York  13210
Tel. 315-473-2794

Philip R. Peterson
Gardner Bldg.,
40 Fountain Street
Providence, Rhode Island 02903
Tel. 401-528^541,2 and 3
                                    13-3

-------
 John O'Connell
 P.O. Box 563
 Montpeher, Vermont 05602
 Tel. 802-223-8433, Com. 223-6754
 George T. Janson
 Leo W. O'Brien Federal Bldg., 9th Floor
 Albany, New York 12207
 Tel. 583-472-6483
 Region 3 - Delaware, Maryland, Pennsylvania, Virginia, and West Virginia
 Alexander J. Stevens - DRMCSO
 Rm. 816-A, Federal Bldg.
 31 Hopkins Plaza
 Baltimore,  Maryland 21201
 AC 301-962^571 or 2. Com. Same

 SAFETY INVESTIGA TORS

 William D. Herster
 Federal Highway Administration
 Motor Carrier Safety Office
 Federal Office Building, 2nd Floor
 300 South New Street, P.O. Box 517
 Dover, Delaware 19901
 Tel. 302-571-5123 or 5153

 James W. Hememann
 1000 N. Glebe Road
 Arlington, Virginia 22201
 Tel. 703-557-9098

 Clyde L. Williams, Jr.
 10-502 Federal Building
 400 N. 8th  Street
 Richmond, Virginia 23219
 Tel. 804-782-2386

 Robert F. Mick
 211 Campbell Avenue, S.W.
 Roanoke, Virginia 24011
 Tel. 703-343-6426
Com.  703-343-1581 Ext. 426

Paul L. O'Neill, Jr.
 Federal Highway Administration
Office of Motor Carrier Safety
 U.S. Post Office  Bldg., Rm. 310
Scranton, Pennsylvania 18503
Tel. 717-344-7325
Com.  717-344-7111
 William C. Savage - RHMS
 Darwin D. Garvin - RAIS
 Joseph J. Fulnecky — S/I
 Ronald G. Ashby - S/I
 William B. Leysath - S/f
 Same address as RD Stevens
James W. De/fenbaugh
P.O.Box 1086
Federal Building
Harrisburg. Pennsylvania 17108
Tel. 717-782-4443

Mark Samuels
James G. Swope. Jr.
Gateway Building, Rm. M-200
Philadelphia, Pennsylvania 19104
Tel. 215-597-1078 or 9, Com. Same

Bernard F. Schilling
Patrick Quigley
Federal Highway Administration
Office of Motor Carrier Safety
Federal Office Building, Rm. 2202
Pittsburgh, Pennsylvania 15222
Tel. 412-644-2935 or 2936

Robert J. Powley
2204 Federal Office Bldg.
500 Quarner Street
Charleston, West Virginia 25301
Tel. 304-343-1211

George F. Neunz
Old Post Office Building, Rm. 416
12th&Chaplme Streets
Wheeling, West Virginia 26003
Tel. 304-343-1031
Com. 304-232-6430
                                     13-4

-------
 Region 4 — Alabama, Georgia, Florida, Mississippi, North Carolina, South Carolina,
           Tennessee, Kentucky
Charles E. Anderson - DRMCSO
Suite 200, 1720 Peachtree Rd., N.W.
Atlanta, Georgia 30309
AC 404-526-5049 or 5966
 William L. Barrow, Jr. - RHMS
 Otis Magby - S/I

 Jimmie B. Sutton - RAIS
 Same Address as RD Anderson
 Tel. 404-526-5049
SA FETY IN VESTIGA TORS

Frank R. Atkins
Room 529
2121 Building
Birmingham, Alabama 35203
Tel. 205-325-3783

Harold H. Rymer, Jr.
P.O. Box 35084
400 W. Bay Street
Jacksonville, Florida 32202
Tel. 904-791-2498

William T. Moss
Box 2014
Miami International Airport
Miami, Florida 33159
Te. 305-526-2921

Jerry A.  Glass
Ackerman Building
223 W. College Ave.
Box 1079
Tallahassee, Florida 32302
Tel. 904-377-4224 or 4259, Ext. 52
Com. 904-224-8111, Ext. 52

Buddy C. Yount
Ernest L. Mann
Federal Building & U.S. Court House
330 W. Broadway
P.O. Box 536
Frankfort, Kentucky 40601
Tel. 502-582-5468
Com. 502-227-7321
Henry M. Laird
Federal Highway Admin.
Bureau of Motor Carrier Safety
666 North Street, Suite 105
Jackson, Mississippi 39202
Tel. 601-948-2292
Com. 601-696^219

Gary A. McCaskill
N. Hugh Galbreath
Bureau of Motor Carrier Safety
Mart Office Bldg., Rm. DD507
800 Briar Creek Road
Charlotte, North Carolina  28205
Tel. 704-372-7457
Com. 372-0711, Ext. 457

Willard T. Hawkins
P.O. Box  26806
Raleigh, North Carolina  27611
Tel. 919-755-4378

James S. Itamura
2001 Assembly St.
Suite 203
Columbia, South Carolina  29201
Tel. 803-765-5414

Robert L. Kener
Bureau of Motor Carrier Safety
2918 E. Magnolia Avenue
Knoxville, Tennessee 37914
Tel. 615-524-4240
Com. 637-9300, Ext. 4240
                                     13-5

-------
Barry Brunstein
Charles Ramsey
Room 1002
Federal Office Bldg.
167 N. Main St.
Memphis, Tennessee  38103
Tel. 901-534-3439
Claude C. Gatlin, Jr.
4004 Hillsboro Road
Suite 236
Nashville, Tennessee  37215
Tel. 615-749-5951
Region 5 — Illinois, Indiana, Ohio, Michigan, Wisconsin and Minnesota
 Wesley A. Bndwell - DRMCSO
 18209 South Dixie Highway
 Homewood, Illinois 60430
 AC 312-799-6300, Ext. 65
SAFETY INVESTIGATORS

Robert K. Seed
Robert A. Nelson
P.O. Box 3307
3085 E. Stevenson Drive
Springfield, Illinois 62708
Tel. 217-525^050, Ext. 37
Com. 217-529-6781

May land B. Nelms, Jr.
Kenneth N. Bostick
Room 707, ISTA Center
150 Market Street
Indianapolis, Indiana 40204
Tel. 317-633-7182 or 83

Gerald Clay
James R. Jeglum
Suite 490, Metro Square Building
Seventh and Robert Streets
St. Paul, Minnesota 55101
Tel. 612-725-7006 or 09
Dennis Martini - RAIS
Gene H. Albers - RHMS
Norbert L. Kuksta - SJI
Clarence L. Hargis - S/I
Vacancy - S/I
Same Address and Telephone number
as RD Bridwell
H. David Howard
Room 4020 C, Federal Building
550 Main Street
Cincinnati, Ohio 45202
Tel. 513-684-2988

Ralph P. Long
Room 2073, Federal Office Building
1240 E. 9th Street
Cleveland, Ohio  44199
Tel. 216-522-1890

Heber Dixon
CarlD. Wolfinger
Bryson Building, Room 321
700 Bryden Road
Columbus, Ohio 43215
Tel. 614-469-5657 or 7493
                                      13-6

-------
Erwin E. Laube
Harold J. Harkins
Richard Boyle
Federal Building, Room 211
Box 147
Lansing, Michigan 48901
Tel. 517-372-1654
Com. 517-372-1910, Ext. 655
William Vickery
Vernon R. Thalacker
P.O. Box  5428
4502 Vernon Boulevard
Madison,  Wisconsin  53705
Tel. 608-252-5215 or 16
Region 6 - Arkansas, Louisiana, Oklahoma, Texas, New Mexico
L. D. Friesen - DRMCSO
819 Taylor Street
Fort Worth, Texas 76102
AC 817-3 34-3 225 or 3 221
SAFETY INVESTIGA TORS

William E. Anderson
3128 Federal Office Building
Little Rock, Arkansas 72201
Tel. 501-378-5625

George W. Wallace
Room 239, Gederal Building
750 Florida Boulevard
Baton Rouge, Louisiana  70801
Tel. 504-348-4244
Com. 504-348-0181, Ext. 244

Philip R. Cardwell
2409 North Broadway
Oklahoma City, Oklahoma 73103
Tel. 405-231-4625 and 26

James E. Martin, Jr.
Jerry F. Smith
Room 3D6, Federal Building
1100 Commerce
Dallas, Texas 75202
Tel. 214-749-2771
Vacancy - RHMS
Elwyn E. Baptiste - RAIS
Joseph  W. Shary (Trainee)
Leon Feazell — S/l
Same Address and Telephone number
as RD Bezner
Clyde C. Coggin, Jr.
Lloyd Hopson
2320 LaBranch, Room 2-68
Houston, Texas  77004
Tel. 713-2264709

Peter W. Davis
619 U.S. Court House & Federal Bldg.
1205 Texas Avenue
Lubbock, Texas 79401
Tel. 806-747-3664

Charles E, Wheeler
Room 206
301 Broadway Building
San Antonio, Texas 78205
Tel. 512-2254377
Com. 512-225-5511, Ext. 4377

Eugene Call
FAA Building
Albuquerque International Airport
2930 Yale Blvd., SE
Albuquerque, New Mexico  87106
                                      13-7

-------
Region 7 - Iowa, Kansas, Missouri, Nebraska
Bryan J. Schreier - DRMCSO
P.O. Box 7186
Country Club Station
Kansas City, Missouri 64113
AC 816-926-7095
William A. Crowder - RHMS
Tel. 816-926-7897
NorrisJ. Freeman — RAIS
Tel. 816-926-7896
James A.  Twigg - S/I
Bernard L. Watson - S/I
Tel. 816-926-7898
Audrey M. Brent - (Trainee)
Same Address as RD Schreier
SAFETY INVESTIGA TORS

William M. Burton
P.O. Box 627
105 6th Street
Ames, Iowa 50010
Tel. 515-232-0231
Com. 515-232-0250, Ext. 231

E. Ray Thompson
Room 915, Federal Building
210 Walnut
Des Moines, Iowa 50309
Tel. 515-284-4417

Robert C. Thompson
P.O. Box 1341
Sioux City, Iowa 51102
Tel. 712-252-0270
Com. 712-252-4161, Ext. 270

Walter Johnson
\263 Topeka Avenue
Topeka, Kansas 66612
Tel. 913-234-8385
Com. 913-234-8661, Ext. 385
Joseph L. Muscaro
P.O. Box 148
209 Adams
Jefferson City, Missouri 65101
Tel. 314^42-5541 or 5542
Com. 314-636-7104

Wayne Cole
Charles L. Drummond
U.S. Courthouse and Custom House
Room 650A
1114 Market Street
St. Louis, Missouri 63101
Tel. 314-622-4109

Robert E. Kitzmiller
Dale L. Meiner
Bilhe C.  Wilson
1701 S.  17th Street
Lincoln, Nebraska 68502
Tel. 402-471-5 523
                                     13-8

-------
Region 8 - Colorado, Utah, Wyoming, Montana, North Dakota, and South Dakota
Luther H. Oldham, Jr. - DRMCSO
Room 151, Building 40
Denver Federal Center
Denver, Colorado 80225
AC 303-234-2339
Ralph D. Graham - RHMS
Harold E. Farsdale - RAIS
Orris H. Gram - S/I
Alexander Buzzell - S/J
Same Address as RD Olkham
Tel. 303-234-2339
SAFETY INVESTIGA TORS

James S. Brunton
11 th and Fee Street
Helena, Montana  59801
Tel. 406-442-3224
Com. 406-442-9040, Ext. 3224

Ronald Evenson
P.O.Box 1755
New Federal Office Building
Bismark, North Dakota  58501
Tel. 701-255-4346
Com. 701-255^011, Ext. 346

William  y. Martin
Box 700
Federal Office Building
Pierre, South Dakota  57501
Tel. 605-224-8241
Com. 605-224-7351

Region 9 - Arizona, California, Nevada

Michael D. Sullivan - DRMCSO
450 Golden Gate Avenue
Box 36096
San Francisco, California 94102
AC 415-5 56-3553 or 4
Wayne Goudie
Alan Brown
2420 Federal Building
Box 11563
Salt Lake City, Utah  84111
Tel. 801-524-5154

John A. Quigley
O'Mahoney Federal Center
2120 Capitol
P.O.Box  1127
Cheyenne, Wyoming  82001
Tel. 307-778-2305
Com. 307-778-2220
Eugene A. Graham - RAIS
Daniel Mulcahy - S//
Byron Stone - S/I
Ralland S. Stevens - Sfl
Same Address and Telephone number
as RD Sullivan
                                     13-9

-------
SAFETY INVESTIGA TORS
George H. Dobbins
3500 N. Central Avenue
Suite 201
Phoenix, Arizona 85012
Tel. 602-261-3751

Rudy Black - RHMS
Harold E. Whitaker
John W. Spivey
Steven J. Polyi
Federal Building, Room 3062
300 North Los Angeles Street
Los Angeles, California 90012
Tel. 213-688^842, 3 or 4

Region 10 - Alaska, Idaho, Oregon, Washington

Vacancy - DRMCSO
Room 412, Mohawk Building
222 S.W. Momson Street
Portland, Oregon  97204
AC 503-221-2093 or 2094
William E. Murphy
106 E.Adams Street
Carson City, Nevada 89701
Tel. 702-885-5335

Walter J. Hannigan
Federal Highway Administration
Federal Building, 2nd Floor
801-1 Street
Sacramento, California  95814
AC 916-449-3 511
Judge R. Shelton - RHMS
Ben P. Quillin-RAlS
Linda Taylor - Trainee
Albert C.  Williams - S/f
Robert M. Hagan - S/l
Same Address and Telephone number
as RD West
SAFETY INVEST/GA TORS

George D. Arnot
1515  13th Street
Anchorage, Alaska 99501
Tel. 907-279-5213

Frank A. York
301 OState Street
P.O. Box 7527
Boise, Idaho  83701
Tel. 208-342-2843
Com. 208-342-2711, 2536, or 2537
Bruce M. Fleming
9021 Federal Office Building
Seattle, Washington 98104
Tel. 206^42-4388

William I. DeLapp
402 U.S. Post Office Building
West 914 Riverside Avenue
Spokane, Washington 99201
Tel. 509^56-2545
                                     13-10

-------
STATE AND LOCAL
NOISE PROGRAMS

-------
         •ALARAMA
          L • 1.  LINN,  JR .
          RADIATION PHYSICIST
          FNVIRONMFNTAL  HEALTH AOMINISTHATION LAB
          STATE OFFICE RLDG.
          MONTfifJMERY, AL  3610*
                                                            PHOMF:
                                                                         ?«.M- » 'i
          CHARLES H.  YOUNGER
          CITY  ATTORNEY
          PO BOX 30R
          HUNTSVILLE* AL 35flpV
PHONF:
FTS:
                                                                     ?05  S39-QM2
          JOHN HUDSON

          PO ROX 1827

                  AL
PHONF:
FTS:
          J. ARONSTEIMi JR.. DIRECTOR
          DEPT. OF PLANNING • DEVELOPMENT
          PO ROX 111*
          MONTGOMERYt AL 361r?
PHONE:
FTS:
                                                                     70S ?
-------
               ?5I W.
               PHOFNIX, A7 85003
               JAMfS A. HETTS                                     PHONF:  f>n? 7'»|-*171
               ftSST. DIRECTOR OF TRANSPORTATION                   rTS:
               PO BOX 5547
               TUCSONt AZ 4ST03
     ••••••••••ARKANSAS


               OFFICE OF  THE GOVERNOR
                                                                  FTS:

               LITTLE ROCK. AR
vj    ••••••••••CALIFORNIA
ui
vn
               A.E. LOWE,  CHIEF                                   PHONES  *J5 8*3-7900
               OFFICE OF NOISE CONTROL                            FTSt
               STATf DEPTt  OF HEALTH
               3151 BERKELEY WAY
               BERKELEY, C
               LT. J.D. DE LUCA                                   PHONE I  lib **S-63»5
               S611 - ZATH STREET                                 FTS(
               SACRAMENTOt CA  95016
                      M. HEATH                                    PHO^F:  Q|6 **5-l*bS
               CALIFORNIA HIGHMAY  PATROL                          FTS;
               ?6|1 96TH STREET
               SACPAWENTO,  CA

-------
W.R. GRFEN
DESIGN AND ENGINEERING
CALIF. DF.PT OF TRAMSPORT4TTON
1120 » STREET
SACRAMENTO- C» 95fll»
                                                  PHONF:
                                                               **"- • «no
J.L. REATON
TECHNICAL AN0 RESEARCH
CALIF. OFPT OF TRANSPORTATION
5900 FOLSOM RLVD
SACoAMENTOi CA 95B19.
                                                   PMONFI
GREGORY HARDING
LOCAL  ASSISTANCE  OFFICER
OFFICF OF PLANNING  •  RESEARCH
MOO - 10™  STREET
SACOAMENTOt  CA 95fl]4
                                                  PHONE:
                                                  FTSS
                                                           9)6 4*5-111*
 ROPFRT  J.  KELLEVt  ASSISTANT PLANNER
 DEVELOPMENT  SERVICES OEPT.
 PO BOX  3222
 ANAHEIM.  CA  92803
                                                  PHONF!
                                                  FTS:
                                                           71* 533-5711
 HM. J. WATTERSON
 BUILDING OEPT. SUPT.
 275 E. OLIVE AVE.
 BURRANK. CA 91502
                                                  PHONE:
                                                  FTSJ
                                                           213 P46-2141
CHARLES W. THOMPSON
CITY MANAGER
CITY HALL
8*?5 SECOND ST
DOWNEYi CA 90241
                                                   PHONF:
                                                   FTS:
                                                            213  HM-0361

-------
HtLLI»M F. CORNETT
CITY ADMINISTRATOR
303 W. COMMONWEALTH
FULl F.RTON. CA 9263?
                  | 7 |
BRUCE P. ALBREDt PLANNING DIRECTOR
CITY OF HAYHftHO
22300 FOOTNILL BLVp.
HAVWARO, CA 945*1
PHONF:
FTS!
CHARLES CHIVETTAi DIRECTOR
COMMUMTV OEVELOPKENT OfPT.
CITY OF LAKEWOOD
PO no* isa
LAKFWOOD* CA 90714
PHONF:
FTSl
213 R66-9T7I
DON ORIGGSi CITY MANAGER

CITY GOVERNMENT BLDG.

FREMONT• CA 9*536
PHO>lF:
FTSl
415 796-3*36
DOUR LA BELLE
DEVELOPMENT AGENCY DIRECTOR
      ACACU PARKMAY
       GROVEt CA 9fl2*0
PHONF:
FTS!
7|4 63B-6851
P. PATRICK MANN
ENVIRONMENTAL STANDARDS SUPERVISOR
CITY OF INGLE«OOD
i MANCHESTER HLVD.
INflLEUOODi CA 90301
PHONF:  213
FTS:

-------
JACK GREENi GENERAL  MANAfiFH
DEPT. OF ENVIRONMENTAL  Oil/it f
RM. 5«jO
CITY HALL EAST
LOS AfcGfLfS, CA
ALRFRT W. OPTICIAN,  NOISE POLLUTION SPEC
H£40 OF ACOUSTICS  DIVISION
DEPT. OF ENVIRONMENTAL QUALITY
BM. S50« CITY  HALL EAST
LOS ANGELES, CA  90012
PHOMF:
FTS;
CECIL RILEY,  CITY  MANAGER

CITY »«ALL

OAKLAND* CA 94612
PHONE:
FTSi
                                                            »IS 2T3-3301
JOHN R.  PKl(.P.  MO,
MEfttT*- OFFICE"
COUNTY OF  ORANGE
6*5 NORTH  ROSS  ST.
SANTA ANA,  CA 9270?
PHONE:
FTSt
7|4 834-3131
 JERRCH.D  R.
 CITY  ADMINISTAATOR
 CITY  MALL
 POMONA,  CA  91769
FTSs
 R.J.  MILLIAMS
 SUPERINTENDENT OF BUILDING
 RM 411,  CITY HALL
 LOS ANGELES, CA 90012
PHONFl
FTS:

-------
JOHN L*NFt ADMINISTRATOR
ADVANCED PLANNING
300 f. CHAPMAN AVE.
ORANGE• fA
MURRAY COOPER
ENVIRONMENTAL HEALTH DIRECTOR
CITY HALL
100 N. GARFIELD
PASADENA. CA 91109
PHfiNF:
rTS:
MERLE G. GARDNER
PLANNING DIRECTOR
clTr HALL
RIVERSIDE* CA 92501
PHONF:
FTS:
714 7BT-T171
R.H. PARKER
CITY ENGINEER
ROOM ?07
CITY HALL
SACRAMENTO. CA 9581*
PHONF:
JAMfs E. DUKES
NOISE ABATEMENT « CONTROL ADMINISTRATOR
FNVFCOMMENTAL QUALITY DEPT.
CITY ADMINISTRATION BLDG.. 20? C ST.
SAN niEGO. CA 92101
PHONE:
FTS;
71* 236-60B0
JACK HATTt BUILDlNR OFFICIAL
HOUSING ADVISORY » APPEAL BOARD
330 *• 20™ AVE.
SAN MATEOt CA 94*03
PMO'jF:
FTS:
*15 57*-6750
GLEN K. GODFREY
                                                               3?8-S310

-------
          SUPFRVISOB-ENVIHONMENTAL  DUALITY HIV.
          3031  TORRANCE HLVO.
          TORPAKCF.  CA 90503
                                                            FTS:
          SALVATORE  f.  CATALANO«  SECY.
          ENVIRONMENTAL REVIFU COMMITTEE
          300 NORTH  0 ST.
          SAN RERNARDlNOt  CA  
-------
          JOHN aRNFYi DIRECTOR
          DEPT OF PLANNING  • COMMUNITY  DEVELOPMENT
          UT» EHPORlA ST.
          AURORAi CO ftOOlO
                                                           to.) »* I -
                                                                    • on
THOMAS I. PEABODV. P.E.
CHIEF' PUBLIC HEALTH ENGINEERING
ENVIRONMENTAL HEALTH SERVICE
DEPT. OF HEALTH • HOSPITALS* UNIT «t H ftTM AVE •
        CO 80?0»
                                                             PHOMFt
                                                             FTSI
303
          DONALD v. SHANFELT
          CNVIRONMF.NTAL CONTROL OFFICER
          REPT OF COMMUNITY DEVELOPMENT
          1580 YARROH ST.
          LAKFVOODt CO  80Z1S
                                                  FTS,
                                                           303  Z3Z-2209
          THOMAS A. MARTIN
          NOISE ABATEMENT OFFICER
          SAFETY DEPARTMENT
          PO ROX isTS
          COLORADO SPRINGSt co
                                                  PHONE I
          DEPARTMENT OF COMMUNITY DEVELOPMENT


          CITY OF LAKEWQOD
          COLORADO
                                                  FTSi
••••••••••CONNECTICUT
          WARREN THURNAUER
          MOTOR VEHICLE SAFETY COORDINATOR
          CONN. ST4T£ MOTOR VEHICLE DEPT
          60 tTATE STREET
          WETNERSFIELD' CT 06109
                                                  PHONFl
                                                  FTS:
?03 566-7390

-------
RORFRT fi JIB ALA
ENVTRONMFNTAL SECTION
CONw. STaTE OFPT OF  TfaNSPOHTATION
?* UOI.COTT HILL "040
WETHfBSFIFLD. CT
PAUL NORTON AIR POLL CONTROL  ENG.
CONN ST. OEPT OF ENVIRONMFNTAL  PROT
AIR COMPLIANCE UNIT
IbS CAPITOL AVE.
HARTFORD. CT  061 IS
        ?03
JOSFPH R. TEOF.SCO  AIR POLL  INSPECTOR
BRIDGEPORT AIR POLLUTION  OEPT
OEPT OF HUMANE AFFAIRS
835 WASHINGTON AVE.
RRIDGEPORT. CT
FTSs
STANLEY J. PAC
OFFICE OF THE MAYOR
PHQ'iF I
FTSi
NEM
             CT
FRAMCIS J. KALAMANt  M.D.
137-139 EAST AVE
         CT
                                                   PHOME i
                                                   FTS,
        203  838-7531
H.A. BOURNE DIRECTOR
ENVIRONMENTAL HEALTH
HEALTH DEPT.
550 MAIN ST
HARTFORD. CT  06103
PHONF!
FTS:

-------
ORLANDO SILVESTRI. DIRECTOR
BUILDING OEPT
HALL or RECORDS. »•« 50?
?00 ORANGE ST.
NEW HAVEN. CT  06*10
                                                   PHONF:
JESSE 0. RORTNMICK
NOISE CONTROL PROGRAM MANAGER

254S2 EXECUTIVE CENTER CIRCLEt  EAST
TALLAHASSEEt FL   3?301
PHONF!
FTSI
                                                           904 4RB-4778
WILLIAM  BENNETT
CHIEF  CODE  COMPLIANCE  OFFICER
CITY OF  FORT  LAUOEPOALE
P.O. DRAWER 1181
FORT LAUOEROALEi  FL   33302
PHONE I
FTS:
                                                           305 527-2121
 WALTER W.  HONOUR* DIVISION CHIEF
 BIO'FNVIRONMENTAL SERVICES 01V.

 SIS WEST SIXTH ST.
 JACKSONVILLE, FL  33206
PHONF:
FTSl
                                                           904 633-3*79
 R. E. FERENCIKt DIRECTOR

 BUILDING DEPT.
 BOX NO. 708
 MIAMI, FL
 PHONF:
 FT«il
                                                            305  4*5-4711
 JAMES FOWLER
 ASST. CITY ATTORNEY
 CITY OF ORLANDO
 400 SOUTH ORANGE AVE.
 ORLANDO. FL  32801
 PHONE:
 FTSt
                                                            30S FU9-2129

-------
          ROBERT  M.  JONES.  DIR NOISE PROGRAMS
          COUNTY  ENV PROTECT TON COMM
          STOVALL PROFESSIONAL BLOG.
          305 N.  MORGAN ST. SIXTH FLOOR
          TAMPAi  FL   33602
                                      B13 2?3-\ 111
                              FTS!
          EMIL n.  HICKS.  JR.
          DIRECTOR. DEPT  OF POLLUTION CONTROL
                              PHONFl
                              FTSt
                                      R13 2P3-13II
          P.O.  BOX 2842
          ST. PETERSBUHG.  FL
33731
••••••••••GEORGIA
          CHARLES A. HEAD. Ill
          CHIEF. SPECIAL OPERATIONS UNIT
          GEORGIA DEPT OF HUMAN RESOURCES
          47 TRINITY AVE.» S.M.
          ATLANTAt GA  30334
                              PHONF :
                              FTS!
40* 656-4871
          H.A. HEHES ASST BUILDING OFFICIAL
          OFFICE OF INSPECTOR OF BLOGS.

          BOO CITY HALL
          ATLANTA. G*  30303
                              PHONE I
                              FTSi
          JOHN talLBANKS
                     C<>UWTY
                              PHOMEt
                              FTS:
                                      41? 746-9656
          PO BOX 247 RH 305 CITY HALL
          HACON, GA  3120?
          ARTHUR A. HENOONSA
          CITY MANAGER
          CITY OF SAVANNAH
          P.O. BOX 1027
                              PHONE:
                              FTSl
412 233-4321

-------
          SAVANKAH,  GA
         CURTISS  E.  MCCLUNG
         CHIEF  OF POLICE

         P.O. BOX 1340
         COLllMPUS* G».   31902
FTS:
          SflOAMOTO IHASHITA
          CHIFF, NOISE * RADIATION BRANCH
          5TATF DEPT. OF MEAI TH
          P.O. POX 3378
          HONOLULU. HI  96801
PHONE:
FTS:
                                                                    BOH 549-3075
          HERREPT MURAOKA
          CITY • COUNTY OF HONOLULU
PHONE:
FTSl
                                                                    BOB  546-7651
          HONOLULU HALE. HONOLULU. Hi  96811
••••••••••IDAHO
          VAUfiHK ANDERSON
          niRFCTOR-CATEGORICAL PROnRAMS

          STATE^OUSE
          BOISE. ID  B37ZO
PHONF:
FTS!
                                                                     208  3R4-23QO
          JAMES L. MORRIS. CITY ENGINEER
          OEPT. "F PUBLIC KOP«S

          CITY HALLt P.O. BOX 500
                 in  83701
                                                                     206 342-4621
 FTSl

-------
JOHN S. MOORE
MGR., DIV. OF NOISF POLL CONTROL

2200 CHURCHILL RO.
SPRINGFIELD, IL  6270*
PHOMF!
FTS!
H.W. POSTONi COMMISSIONER
OEPT OF ENVIRONMENTAL CONTROL
320 N. CLARK ST. RH *02
CHICAGO, IL  60610
PHOuFl
FTSi
                                                           112 T44-4080
FRANK OSINSKI
dTV-COUNTV HEALTH OEPT

WINNEREGA CO. COURTHOUSE
ROCKFORD. IL
PHOMF. I
FTSI
BIS 9fl7-?575
RALPH C. PICKARO
INDIANA STATE BOARD OF HEALTH

1330 bEST MICHIGAN ST.
INOlAMAPOLlSi IN  46206
PHONE!
FTSI
317 633.4*20
JESSE C. CROOKS* DIRECTOR
ENvIRONMfNTAL PROTECTION AGENCY
RM  ?07, ADMINISTRATION BLDG.
CIVIC CENTER COMPLEX
EVANSVILLE.  IN  47708
PHONF:   «12 *2*-5595
 JOEL JOHNSONi  DIRECTOR


 3600 M.  3RD  AVE
                                                               944-679S
 FTS.

-------
         GABY.  IN   46406
         RONALD L. NOVAK.  CHIEF
         HAMMOND  AIR  POLLUTION CONTROL

         5925 CALUMET AVE.
         HAMMOND,  IN   46320
PHONE1:
FTS:
          HAROLD  J.  EOENES
          DIRECTOR*  DEPT  or METROPOLITAN OEV.

          I8C.O CITY-COUNTY flLDG.
                        IM  46204
PHONF:  117 633-3198
          CAPT.  JAMES R.  SMEITZER
          701  U.  SAMPLE
          SOUTH BEND* IN  46621
PHONE I
FTSI
219 28*-
-------
          MELVILLE  W.  GRAY,  DIRECTOR
          o'v's'ON  OF  ENVIRONMENTAL HEALTH
          KANSAS  STATE OEPT  OF  HEALTH
          535 KANSAS AVE
          TOPFKA, KS  66603
PHONF:
FTS:
••••••••••KENTUCKY
          FHEO HATERS ENVIRONMENTAL SUPERVISOR
          OEPT OF NATURAL RESOURCES • E.P.
          DIVISION OF SPECIAL PROGRAMS
          CAPITAL PLAZA BLOC. '
          FRANKFORT* KV  40601
PHONF!
FTSt
                                                                    502 564-7274
• •••••••••LOUSI ANA
          VERNON C. PARKERi HEAD
          OIV AIR CONTRL « OCCUPATIONAL HLTH
          RM »U-325 LOYOLA AVE*
          P.O. BOX 60630
          NEW ORLEANS. LA  70160
PHONE:
FTS!
                                                                     50*  527.5115
          c. CURTIS MANN, CHF MECHANICAL  INSP

          RM. 7E04. CITY HALL
          13UO PERDIOO ST.
          NEW ORLEANS, LA  70112
 PHONE:
 FTSi
                                                                     504 586-4*55
           L. TALHOUNi  JR.
           MAYOR.  CITY  OF SHREVEPORT

           1Z3*  TEXAS AVE.
           SHREVEPORT.  LA
 PHONFI
 FTSI
                                                                     504 424-4171
 ••••••••••MAINE
           DONALD C.  HOXIE
                                                             PHONF:  207 2H9-3126

-------
          DIRECTOR. HEALTH ENGINEERING

          MAINE DEPT OF HEALTH • WELFARE
          AUGUSTA. ME
                                                            FTS!
••••••••••MARYLAND
          THOMAS A. TOWERS. SANITARIAN
                 OF AIR QUALITY CONTROL
          610 NORTH HOWARD ST
          BALTIMORE' HO  21201
FTS!
          DAVID T. LEWIS. DIRECTOR
          RURFAU OF ENV NOISE  CONTROL
          60? AMERICAN RLOG.
          BALTIMORE • SOUTH STREETS
          BALTIMORE! MO  31202
PHONE:
FTSl
                                                                     301  346-4428
 ••••••••••MASSACHUSETTS
           MR.  GILBERT  T.  JOLYt  DIRECTOR
           MASS.  DEPT PUBLIC HEALTH
           BUREAU OF AIR QUALITY CONTROL

           SPRINGFIELD* MA
 PHONFi
 FTS«
           PCNtLP C. SQUIRES
           31 sriTE ST. *TM
           TSVN. "A  OZ10»
                                 CONTROL
                                                                     617 2?7-4890
                                                             FTS:
                    LlSS
            D1R. ENVIRONMENTAL CONTROL OFFICE

            LYNN CITY HALL
            LVNN, MA  01904
  FTS:

-------
JOSFPH A. PELLET IER
POLICE CHIEF

SPRING STREET
NEU BEDFORD, MA 027*0
                                                                 PMONFS
                                                                 FTS!
JAMES BARHETTt DEPUTY CHIEF
BUREAU OF INDUSTRIAL HEALTH
MICHIGAN DEPT OF PUBLIC HEALTH
3500 *• LOGAN ST.
LAKlSINGt MI
                                                  PHONF J
                                                  FTSl
                                                                         51? 373-1*10
s
               WAYNE  COUNTY HEALTH DEPT



               HERRICAN RO
               ELOISE,  Ml   48132
                                                   PHONE:
                                                   FTS;
                                                                         313 27*-2Boo
               JAHES A. 8IENER.  DIRECTOR
                                                   PHONE:
                                                   FTSI
                                                                         616 456-3Z06
               500 WEALTHY,  S.M.
               GRAND RAPIDS, MI  49503
BRUCE C. BROWN
DIRECTOR OF CITY PLANNING

241 W. SOUTH ST.
KALAMAZOOt MI  49Q06
                                                   PHONE:
                                                   FTS«
                                                                         616 301-5500
 FRANK  A.  KERBY
 CHIEF  INSPECTOR

 15200  FARMINGTON ROAD
                                                                          313  421-2000
                                                                 FTSs

-------
          LIVONIA.  HI  4B1S4
          ROSF.RT M.  GERDS?  ADMINISTRATOR                    PMONFI
          INSPECTION SERVICES DIV.                           FTS:

          CITT OF PONT I AC
          PONTIAC, HI
          ROGER BALTMAi FED PROJECTS ENGINEER               PHONF:  517 753-5*11

          TRAFFIC ENGINEERING Oly.                          FTSl


          CITV MALL
          SAGINAW. MI  40601
          GEORGE BRUGGERMAN(  DIRECTOR                       PHONEJ  313 573-9500
          DIV. OF RUILOINGS • SAFTV ENOINEERNG              FTS>

          29500 VAN OYKE
          WARpENt MI  *8093
••••••••••MINNESOTA
          RORERT L. LINES•  SUPERVISOR                       PHONE I  612 348-2637
          POLLUTION CONTROL DIV.                            FTSl

          220 GROIN EXCHANGE
          MINNEAPOLIS, MN  55415
          KEN OZUGANt DIRECTOR                              PHONEt  612 24H-5521
          CITY OF ST. PAUL                                  FTS«
          POLlUTION CONTROL SERVICE
          100 EAST 10TH ST.
          ST PAULt MN  55101
••••••••••MISSISSIPPI

-------
          VCLNEY  J.  CISSNA.  JR.  »IP
          ftSST. PLANNING DIRECTOR
          210 SOUTH  PRESIDENT
          P.O. HO* ??56«
          JACKSON, MS  39205
PHONF:
         •MISSOURI
          GLEN J. HOPKINS
          SPECIAL ftSST. TO CITY MANAGER

          29TH FLOOR' CITY M«LL
          KANSAS CITY, MQ  64IO&
PHOMC!
FTSl
B16
          JOE ALLEN. CHIEF
          AID POLL^TION CONTROL AUTHOR|TY

          CITY HALL-BOO BOONVILLE ftVE
          SPRINGFIELD. MO
PHONF:  *17 865-1611
          LARRY L. LLOYDi CHIEF
          OCCUPATIONAL HEALTH BUREAU
          OEPT OF HEALTH • ENV SCIENCES
          COGSWELL BLOC.
          HELENA. MT  59621
FTSl
••••••••••NERPASKA

          J.L. WIGGINS, DIRECTOR

          P.O. BOX 9*653. ST HOUSE STATION
          LINCOLN, MB  68509
PHONE:
FTS»
*02 471-2186
          GARY L. WALSH. CHIFF
                                                            PHONFi   403 475-6??l

-------
               AIR POLLUTION CONTROL  SECTION

               2200  ST. MARYS  AVE.
               LINCOLN. NB  69502
             ••NEVADA


               LT.  COL. BERNARD  DFHL                              PHONFt   702 8R2-T351
               ASST CHIEF  NEVADA HGHWY  PATROL                    FTS«

               555  WRIGHT  WAY
               CARSON CITY, NV   89701
               RORFRT C.  CLEANER                                  PHOWF!  702 3B6-6011
               SUPF»V1SOR Op  ZONING                               FTSl

               400  E STEWART  AVE.
                   VEGAS. NV   091QI
3              BRIAN WRIGHTt  ACTING DIRECTOR                     PHONF.:  ?02 785-4246
               01V OF ENVIRONMENTAL PROTECTION                   FTSl

               10  KIRHAN AyE.
               RENO* NV  B9502
     ••••••••••NEW JERSEY


               EDWARD J. 01 POLVERE                              PMONFl  609 292-7695
               SUPFRVISOR OF NOISF CONTROL OFFICE                FTSl

               BOX 2807
               TRENTON, NJ  08625
               STUART B. PALFREYMAN. H.O.                        PHONEt
               HEALTH OFFICER                                    FTSl
               CLIFTON HEALTH
               CLIFTON, N.J.  07011

-------
          BUFORD.  DIRECTOR
    OEPT  OF  HEALTH »  WfLFARE

    CITt  MALL-RM 210
            N.J.   0710?
FTS:
        MFMCO
    AARON  BONO,  DIRECTOR
    ENVIRONMFNTAL  IMPROVEMENT  AGENCY
    ST«TE  OF  NEW MEXICO
    P.O. POX  ?3»8
    SANTA  FE. N.M.   8TS01
PMONF:
FTSJ
SOS 8?7-2*73
••••NEK YORK
    OR.  FRED 6.  HAAG.  DIRECTOR
    NOISE  BUREAU
    50 WOLF  ROAD
    ALPANV,  N.V.  12201
PHONE:
FTS5
518 457-1005
    SGT.  FREDERIC  J.  WELSH #5


    90 BEAUFORT PL.
    NEW ROCHELLE.  N.Y.   10801
PHONE I
            632-2021
    RAYHO*D E.  GERSON DIRECTOR
    BUREAU  NOISE  ABATEMENT

    120 HALL ST.
    NEW YORK,  N.Y.   10005
PHONF:
FTS,
    JOHN f.  MATTHEWS
PHONF:  518 393-6661

-------
               SCHENECTADY COUNTY PLANNING OEPT
                                                                 FTS:
               620 STATE ST.
               SCHFNECTAOV, N.V.
                                  12307
 PETFR  MANCUSO*  DIRECTOR
 DIVISION  OF  NOISE  FNFORCEMENT
                                                                 PHONFt
                                                                 FTS,
 120  MALL  ST.
 NEW  TfflRK,  N.t.
                               10005
     ••••••••••NORTH  CAROLINA
ROY PAUL
ENVIRONMENTAL PLANNER
OFFICE OF STATE PLANNING
116 WEST JONES STRFET
RALFIGH, NC ZT603
                                                                 PMOK)F|
                                                                 FTSl
w
DALE *. LONG CHIEF ZONING  INSPECTOR
INSPECTION OEPT
CITY OF CHARLOTTE
CITY HALL* 600 EAST TRADE  ST.
CHARLOTTE* NC  28202
                                                  PMOMEl
                                                  FTS.
                                                                         70* 3T4-22M
r.L. KCPMEHSON
ADMIN. ASST.t CITY HALL

CITY OF DURHAM
DURHAM. NC
                                                                PHONE:
                                                                FTS:
ROBERT GOODWIN
CHIEF OF POLICE

P.O. ROX 590
RALEIGH. NC  2T602
                                                  PHONF:
                                                  FTS,
                                                                        919 755-6370

-------
          ORvlLLE u. POuELL
          CITY MANAGER* CITY OF WINSTON
PHONF:
FTS:
          WINSTON S»LEM, NC  27102
••••••••••OHIO
          OR. IRA L.  WHITMAN
          OHIO FPA
          BOX 1049
          451 F TOWN  ST.
          COLUMBUS, OH  43?|ft
PHONF:
FTS:
614 469-3543
          JOHN 0.  MORLEVt  M.n.
          DIRECTOR OF  HEALTH
          DEPT OF  PUBLIC  HEALTH
          177  S. BROADWAY
          AKRDNt OH 4431)8
PHONE!
FTS«
          CHARLES  H.  LENZER ACTING ASST  CO"*M.
          ENVIRONMENTAL  CONTROL  CONSUMER PROT
          CINCINNATI  HEALTH nEPT.
          3101  BUHNET AVE.
          CINCINNATI, OH 45?29
PHONE:
FTS!
513 352-3158
          BOYD  T.  MARSH
          DEPUTY HEALTH  COMMISSIONER
          FOR FNVIRONMENTAL  HEALTH
          14?5  ST.  CLAIR AVE.
          CLEVELAND  OH   44114
PHDNF!
FTSl
216 694-230*
         GEORGE K. HODGE
         SUPFRINTENDENT

         181 S WASHINGTON SLVD
         COL"MRUs, OH  43215
PHONE:
FTS:
(.14 461-7433

-------
         FRANCIS fi. CASH
         ZONING ADMINISTRATOR
         CITY OF DAYTON
         101 H. THIRD ST.
         DAYTONi OH  45*02
PMONr:
FTS:
                                                                    S|3
         EVOp  S.  KERRt  JR.
         OIRFCTOR OF  PUBLIC  SAFETY

         6611  RIDGE ROAD
         PARMA, OH 4*129
PHONE:
FTS:
                                                                    216 6*6-2323
          PAUL  0.  FINOLAY.  DIRECTOR
          POLLUTION CONTROL AGENCY

          26 MAIN  STREET
          TOLEDO.  OH 43605
                                                            PHONE:  419 255-1500
          FRED P.  VICAREL
          CHIEF OF SANITARY POLICE
          CITY HALL« HEALTH DEPT.
          YOUNGSTOMN. OH  44503
PHONE t
FTS!
                                                                    216 744-8989
••••••••••OKLAHOMA
          DALE HCHARO. CHIEF
          OCCUPATIONAL RAD H|_TH SERVICES
          STaTE OEPT OF HEALTH
          NORTHEAST loTH • STONEWALL
          OKLAHOMA CITY. OK  73105
 PHONE I
 FTS:
                                                                    405  271-5221
          IVAN B. SMITH. CHIEF
          OCCUPATIONAL RAD HuTH SECTION
          921 N.E. 23
          BOX 53445
          OKLAHOMA CITY. OK  73105
                                                                     405  427-8651
 FTS:

-------
          GEORGA  H.  PROTHRO.  M.D.
                                                            FTS:
          TULSA  CITY-COUNTY HLTH DEPT.
          P.O.  BOX  4650
          TULSA,  OK  7*104
••••••••••OREfiOfc
          JOHN HECTOR,  CHIEF
          NOISE POLLUTION CONTROL SECTION
                                        PHONE:
                                        FTS:
503 229-5284
          1234 S.w,
          PORTLAND.
MORRISON ST.
OR  97205
          DR. PAUL HERMAN
          ACOUSTICAL PROJECT MANAGER
          RUREAU OF NEIGHBORHOOD ENVIRONMENT
          ?D4o S.E. POMELL BLVD.
          PORTLAND. OR  9720?
                                        PHOME I

                                        FTSt
503 248-4*65
••••••••••PENNSYLVANIA
          CLARK L. GAULDING, DIRECTOR
          BUREAU AIR QUALITY * NOISE CONTROL
                                        PHONE:
                                        FTSI
TIT 7B7-9702
          HARRISRURGi PA
          GEORGE s. SMITH, MD
          MEDICAL DIRECTOR
          BI-CITY HEALTH RURFAU
          415 HAMILTON ST.
          ALLENTOUN, PA  \B\ol
                                         PHONE:
                                         FTS:
215 437-7T59

-------
          RICHARD J.  GOFF
          NOISE CONTROL SPECIALIST

          649 CITY-COUNTY  SLOG.
          PITTSBURGH* P»
                                                  PHONF:
                                                  FTS:
                                                                    «12 35S-4030
          RICHARD L.  HUflERi  NO
          DIRECTOR OF PUBLIC HEALTH
          SCRANTON. PA
                                                  PHONE I
                                                  FTSs
••••••••••RHODE ISLAND
          EUGENE J. JEFFERSt P.E.
          CITY ENGINEER

          137 ROOSEVELT AVE.
          PA«TUCKETt RI  028*0
                                                  PHONE I
                                                  FTS«
                                                                    401 728-0500
VINCENT 01 MASEt P.E.
DIRECTOR DEPT OF RLOG. INSPECTION

112 UMON ST.
PROVIDENCE* RI  02903
                                                            PHONF. I
                                                            FTSI
            . COSTELLO* BUILDING INSPECTOR
                                                  PHONFt
                                                  FTSl
                                                                     401  T3T-221I
CITY MALL
WARWICK, RI
                       02886
••••••••••SOUTH CAROLINA
          JOHNNIE W. SMITH, niRECTOR
          DIVISION OF NOISE CONTROL
                                                  PHONFi
                                                  FTS:
                                                                     803 758-8950
2600 BULL ST.
COLUMBIA. S.C
                           29201

-------
          JAMES  H.  NORTON
          POLLUTION CONTROL  OFFICIAL
          P.O.  POX  1*7
          COLUMBIA.  S.C.
                                                            PHONF:  R03 7hS-lO*l
          JOEL HARNETT ENGINEER
          IN CHARGE NOISE CONTROL ACTIVITIES

          C2-?12 COROELL HULL  BLOG.
          NASHVILLE. TN
PHONE I
FTS:
                                                                    615 7*1-3651
••••••••••TEXAS
          STUART HENRTt DIRECTOR
          P.O. iox lose
          AUSTIN, TX  7B767
PHONE I
FTS!
512 '72-6981
          H.R. METZZER, M.O. M.P.H.
          DIRECTOR. CORPUS-CHRISTI-NUECES CO.
          OEPT OF PUBLIC HEAI.TM » WELFARE
          P.O. BOX 49
          CORPUS CHRISTI. TX  78403
PHONFt
FTS!
          LARRY J. FREEMAN. DEPUTY DIRECTOR
          ENVIRONMENTAL CONSERVATION DIV.

          193A AHELI* COURT
          DALLAS. TX  75235
PHQMF. :
FTS:
21* 638-7670

-------
          JOHN V. COHB1. ACTING DIRECTOR
          OCCUPATIONAL HLTH » RADIATION CONTRL
          NOISE INVESTIGATION
          1115 N. MACGREGOR
          HOUSTON, TX  7T025
                                                                    713
FTS!
          EARL  M. AYLES. DIRECTOR


          635 W. IRVING BLVD.
          IRVING, TX 75060
PHONF:  21* 259-3771
          E.J.
          ASST. CITY ATTORNEY
          P.O. BOX 672
          1211 E. 50UTHMORE
          PASADENA* TX  TTS01
                                                                    T13 477-1511
••••••••••VIRGINIA
          BRYCE P. SCHOFIEUD, DIRECTOR
          BUREAU OF INDUSTRIAL HYGIENE

          109 GOVERNOR ST.
          RICHMOND, VA  Z321Q
PHONE:
FTSS
80* 770-6285
          P.C. MINETTI
          CHIEF OF POLICE

          CITY HALL
          HAMPTON, VA  73369
PHONE I  ftO* 7?2-2535
          DONALD u. MATHIAS
          ENVIRONMENTAL MONITOR
          RM. HO*
          CITY HALL
          NORFOLK. VA  23501
PHONE:
FTS:
BO* **1-?«21

-------
         •WASHINGTON
          RUSSELL C.  HUEHLER
          DIRECTOR OF PLANNING
          RM 335 COUNTY-CITY BLDG.
          <>30 TACOMA  AVE. SOUTH
          TACOMA. WA   98*03
PHONF:
rTS:
            593-4170
••••••••••WEST VIRGINIA
          HARVEY J. ROBERTS. DIRECTOR
          RURFAU OF INDUSTRIAL HYGIENE
          W. VA DEPT. OF HEALTH
          7Boo E WASHINGTON ST.
          CHARLESTONt WV  ?5305
PHONE:

FTS:
304 348-3526
••••••••••WISCONSIN
          BROOKS BECKER. DIRECTOR
          BUREAU OF AIR POLLUTION CONTROL
          SOLID WASTE MANAGEMENT
          OEPT NATURAL RESOURCES BOX 450
          MADISON. WI  53TQ1
PHONE!
FTSS
          0. FRED NELSON. GEN. MANAGER

          KENOSHA WATER UTILITY

          KENOSHA MUNICIPAL RLDG.
          625-52ND ST

          KENOSHA. WI  531*0
PHONE»

FTSl
*1* 658-1374
          DAVID c. COUPER
          CHIEF OF POLICE
          311 S CARROLL ST
          P.O. ROX lisa
          MADISON, MI  53703
PHONE!
FTS.
608 266-*275

-------
          GEORGE A. KUPFER. SUPERINTENDENT                  PHOnjP r   4]*  27(1-167*.
          BUREAU OF CONSUMER PROTECTION                     FTS!
          • FNWI»ONMENT»L HEALTH
          RM 105 i MUNICIPAL RL06 841 M HROAI)UT
          MILWAUKEE* HI  53203
          OR FERRAZDANO                                     PHONE:  414  636-920*
          RACINE HEALTH DEPT.                               FTS:
          RACINE. Wl 53203
••••••••••DISTRICT OF COLUMBIA


          DAVID-N. STAPLESt CHIEF                           PHONFI  ?02  629-Z12B
          INOIISTRIaL HYGIENE DIV.                           FTS:
          DEPT OF ENV SERVICFS
          801 NORTH CAPITOL ST RM 773
          WASHINGTON' O.C.  20002
                 RICO
          SANTOS ROHENAt JR.                                PHONF!
          ASSOC. DIRECTOR SOLID HASTE                       FTS:

          C/0 OFFICE OF THE GOVERNOR
          COMMOMHEALTH OF PUERTO RICO
••••••••••VIRGIN ISLANDS


          DONALD C. FRANCOIS                                PHONE:  B09  774-3411
          ASST. DIRECTOR                                    TTS:
          ENVIRONMENTAL HEALTH
          P.O. BOX 1442
          ST. THOMAS* vi  oonoi

-------
14. TRADE ASSOCIATIONS. PUBLICATIONS.
        AND RADIO STATIONS

-------
            SECTION



                 14



TRADE  ASSOCIATIONS



  PUBLICATIONS  AND



     RADIO  STATIONS

-------
                          INDEX
1.   National  Trucking Associations
2.   State Trucking Associations

3.   Independent Trucking Associations
4.   Trade Journals
5.   Truckers' Radio Stations

-------
1.  NATIONAL TRUCKING ASSOCIATIONS

-------
NATIONAL TRUCKING ASSOCIATIONS

American Association of
  Motor Vehicle Administration
1828 L Street, N.W.
Suite 500
Washington, D.C.  20036
Louis Spitz - Exec. Director
  296-1955

American Trucking Association
1616 P Street, N.W.
Washington, D.C.  20036
Bill Gibson - Engr.
  769-5335

National Association of Motor
  Bus Owners (NAMBO)
1025 Connecticut venue, N.W.
Washington, D.C.  20036
Stan Hamilton - Govt. Liaison
  293-5890

National Association of Truck
  Stop Operators (NATSO)
501 Slaters Lane, Suite 5
Alexandria, Virginia  22314
549-2100

Private Truck Council of America, Inc,
1101 14th Street, N.W.
Washington, D.C.  20036
John White - Exec. Vice President
  785-4900

-------
        AMERICAN TRUCKING ASSN. CONFERENCES
 AMERICAN MOVERS CONFERENCE
     Charles C. (Chuck) Coon, President
     American Movers Conference
     1117 North 19th Street - Suite 806
     Arlington, Virginia 22209
         Office Phone:  (703) 524-5440

 COMMON CARRIER CONFERENCE-IRREGULAR ROUTE
     Henry A.S. van Daalen, Executive Director
     Common Carrier Conference-Irregular Route
     1616 P Street, N.W.
     Washington, D.C. 20036
         Office Phone:  (202) 797-5286
         "Hot Line": (202) 797-5289

 CONTRACT CARRIER CONFERENCE
     James W. (Jim) Boyer, Managing Director
     Contract Carrier Conference
     1616 P Street, N.W.
     Washington, D.C. 20036
         Office Phone:   (202) 797-5401
         "Hot Line": (202) 797-5402

FILM, AIR & PACKAGE CARRIERS  CONFERENCE
     George H.  Mundell, Secy. & Exec. Director
     Film, Air & Package Carriers Conference
     1616 P Street, N.W.
     Washington, D. C. 20036
         Office Phone:  (202) 797-5365

HE A VY-SPECIALIZED CARRIERS CONFERENCE
     Allan M. (AJ) Shirley, Managing Director
     Heavy-Specialized Carriers Conference
     1155 - 16th St., N.W., Suite 711
     Washington, D. C. 20036
         Office Phone:  (202) 797-5407
         "Hot Line":  (202 797-5443

-------
LOCAL AND SHORT HAUL CARRIERS NATIONAL CONFERENCE
    Fred G. Favor, Executive Director
    Local & Short Haul Carriers National Conference
    1621 O Street, N.W.
    Washington, D.C. 20036
         Office Phone:  (202) 797-5414

MUNITIONS CARRIERS CONFERENCE
    William J.  (Bill) Welsh, Managing Director
    Munitions  Carriers  Conference
    1616 P Street, N.W.
    Washington, D.C.  20036
         Office Phone:  (202) 797-5419

NATIONAL AUTOMOBILE TRANSPORTERS ASSOCIATION
    Douglas W. (Doug) McGiveron, General Manager
    National Automobile Transporters Association
    Suite 388 - Mt. Vernon Quadrangle
    23777 Greenfield Road
    Southfield, Michigan 48075
         Office Phone:  (313) 557-8855

NATIONAL  TANK TRUCK CARRIERS, INC.
    Clifford J.  (Cliff) Harvison, Managing Director
    National Tank Truck Carriers, Inc.
    1616 P Street, N.W.
    Washington, D.C. 20036
         Office Phone:  (202) 797-5425

OIL FIELD HA ULERS  CONFERENCE
    James R. (Jimrnje) Boyd, Secretary
    Oil Field Haulers Conference
    P.O.  Box 488, 406 East  11 th Street
    Austin, Texas 78767
         Office Phone:   (512) 476-5326

PRIVATE CARRIER CONFERENCE
    Vincent L. (Vince) O'Donnell, Managing Director
    Private Carrier Conference, Inc.
    1616 P Street, N.W.
    Washington, D.C. 20036
         Office Phone:   (202) 797-5404 or 797-5405

-------
REGULAR COMMON CARRIER CONFERENCE
    R. Edwin (Ed) Brady, Executive Director
    Regular Common Carrier Conference
    1616 P Street, N.W.
    Washington, D.C. 20036
        Office Phone:  (202) 797-5268

STEEL CARRIERS CONFERENCE OF ATA
    H. Scott (Bob) Byerly, Managing Director
    Steel Carriers  Conference of ATA
    1616 P Street, N.W.
    Washington, D.C. 20036
        Office Phone-  (202) 797-5406

                CANADIAN ASSOCIATIONS

NA TIONA L ASSOCIA TION
    A. K. (Ken) Maclaren, Executive Director
    Canadian Trucking Association
    130 Albert Street, Suite 300
    Ottawa, Canada KIP 5G4
        Office Phone.  (613)236-9426

PROVINCIAL ASSOCIATIONS

ALBERTA
    R. J. (Bob) Drinnan, Executive Secretary
    Alberta Motor Transport Association
    5112-3 St., S.E., P.O. Box 5520, Stn. "A"
    Calgary,  Alberta, Canada T2H 1J6
        Office Phone:  253-8401, 8402 or 8403

ATLANTIC PROVINCES (New Brunswick, Newfoundland,
Nova Scotia and Prince Edward Island)
    Charles R. Allen, Secretary-Manager
    Atlantic  Provinces Trucking Association
    Box 480
    Hartland, New Brunswick, Canada
        Office Phone:  (506) 375-6924

BRITISH COLUMBIA
    Ray E. Hunt,  Secy-Manager
    Automotive Transport Association of B.C.
    4090 Gravely  Street
    Burnaby V5C 3T6 B.C., Canada
        Office Phone:  (604) 299-7407

-------
MANITOBA
    John (Jack) Veitch, General Manager
    Manitoba Trucking Association
    66 E Polo Park Shopping Centre
    Winnipeg,  Manitoba R3G OW4
        Office Phone  (204) 744-5780
        "Hot Line":  (204) 775-1550

ONTARIO
    J O. (Joe) Goodman, General Manager
    Ontario Trucking Associations
    555 Dixon Road
    Rexdale, Ontario M9W 1HB Canada
        Office Phone: (416) 247-7131
        "Hot Line".  (416) 247-791 I

QUEBEC
    Cainille Archambault, Exec. Vice Pros.
    Trucking Association of Quebec,  Inc.
    8575 Boulevard-Pascal-Gagnon
    Montreal 458, Quebec, Canada
        Office Phone' (514)322-8120

SASKATCHEWAN
    T. D. (Tom) Durbin, General Manager
    Saskatchewan Trucking Association
    1324 Wallace Street
    Regina, Saskatchewan, Canada
        Office Phone: 569-9696

              WESTERN HIGHWAY INSTITUTE

    Jess N. Rosenberg, Executive Director
    Western Highway Institute
    333 Pine Street
    San Francisco, California 94104
        Office Phone: (415)986-4069
        "Hot Line":  (415)986-0557

-------
2.  STATE TRUCKING ASSOCIATIONS

-------
STATE TRUCKING ASSOCIATIONS
Mr. James I. Ritchie
Exec. Vice President
Alabama Trucking Assn., Inc.
247 Associations Bldg.
Montgomery, Ala.  36104

Mr. Edward R. Sanders
Managing Director
Alaska Carriers Assn., Inc.
3443 Minnesota Drive
Anchorage, Alaska  99503

Mr. Terry Smalley
Managing Director
Ariz. Motor Transp. Assn.
2111 W. McDowell Road
Phoenix, Ariz.  85009

Mr. Stewart K. Frosser
General Manager
Arkansas Bus & Truck Assn.
P. 0. Box 2793
Little Rock, Arkansas  72205

Mr. Thomas Schumacher
Managing Director
California Trucking Assn.
1240 Bayshore Highway
Burlingame, California  94010

Mr. Earl Wennergren
Managing Director
Colorado Motor Carriers
 Association
4060 Elati Street
Denver, Colo.  80216

Mr. John E. Blasko
Exec. Vice President
Motor Transp. Assn-   of
  Connecticut, Inc.
508 Tolland Street
E. Hartford, Conn.  06108

Mr. William H. McFadden
General Manager
Delaware Motor Transport
 Association
P. 0. Box 343
Dover, Delaware  19901

-------
 STATE TRUCKING ASSOCIATIONS
Mr. Andrew W. Johnson
Exec. Vice President
Washington, D.C. Area
  Trucking Assn.,  Inc.
1616 P Street, NW
Washington, D.C.   20036

Mr. C. A. Gertner
Managing Director
Florida Trucking Assn.,  Inc.
P. 0. Box 238
Jacksonville, Florida  32204

Mr. Charles L. Skinner
Managing Director
Georgia Motor Truck Assn.
500 Piedmont Avenue, NE
Atlanta, Georgia   30308

Mr. John Farnell
Exec. Vice President
Hawaii Trucking Assn., Inc.
P. 0. Box 3106
Honolulu, Hawaii   96802

Mr. Claude E. Abel
Director
Idaho Motor Transp. Assn.
P. 0. Box 550
Boise, Idaho  83701

Mr. Keith Cecil
Exec. Vice President
Central Motor Freight Assn.
  of Illinois
15 Spinning Wheel Road
Hinsdale, 111.  80521

Mr. George C.  Cline
General Manager
Indiana Motor Truck Assn.
2165 South High School Road
Indianapolis,  Ind.   46241

Mr. Richard G. Hileman
Executive Secretary
Iowa Motor Truck Assn.
1533 Linden
Des Moines,  Iowa  50309

-------
STATE TRUCKING ASSOCIATIONS
Ms. Mary Turkington
Managing Director
Kansas Motor Carriers Assn.
P. 0. Box 1673
Topeka, Kansas  66601

Mr. Paul K. Young
Managing Director
Kentucky Motor Transport
  Assn., Inc.
5th and Walnut Streets
Louisville, Kentucky  40202

Mr. Edmond P. Bacon
Executive Director
Louisiana Motor Transport
  Assn., Inc.
P. 0. Box 1326
Baton Rouge, LA  70821

Mr. Eugene L. Coffen
General Manager
Maine Truck Owners Assn.
615 Congress Street
Portland, Maine  04101

Mr. Albert J. Mascaro
General Manager
Maryland Motor Truck Assn.
3000 Washington Boulevard
Baltimore, Maryland  21230

John M. Breanahan, Sc. D.
Executive Vice President
Massachusetts Motor Truck
  Assn., Inc.
262 Washington Street
Boston, Massachusetts  02108

Mr. Jack L. McNamara
Manager Director
Michigan Trucking Assn., Inc
501 South Capitol Ave.
Lansing, Michigan  48933

Mr. James N. Denn
General Manager
Minnesota Motor Transport Assn,
1821 University Avenue
St. Paul, Minnesota  55104

-------
 STATE TRUCKING ASSOCIATIONS
 Mr.  James  N.  Denn
 General  Manager
 Minnesota  Motor Transport Assn.
 1821 University Avenue
 St.  Paul,  Minnesota   55104

 Mr.  Robert L.  Wheeler
 General  Manager
 Mississippi Trucking  Assn.
 P. O.  Box  3728
 Jackson, Miss.   39205

 Mr.  George W.  Burruss
 Exec.  Vice President
 Missouri Bus  & Truck  Assn.
 201  E. Capital Avenue
 Jefferson  City,  Mo.

 Mr.  Leonard W.  Eckel
 Managing Director
 Montana Motor  Transp. Assn.
 First  Security Bank Bldg.
 1727  llth  Avenue
 Helena, Montana   59601

 Mr.  James  N. Preston
 Managing Director
 Nebraska Motor  Carriers Assn., Inc.
 521  S. 14th Street
 Lincoln, Neb.   68508

 Mr.  Robert  F.  Guinn
 Managing Director
 Nevada Motor Transp. Assn.
 P. 0. Box  7415
 Reno, Nevada   89502

 Mr. A. J. Lagasse
 Executive Director
Motor Transport Assn.
  of New Hampshire
 P. 0. Box 665
Manchester, N. H.  03105

Mr. Thomas F.  X. Foley
 Executive Director
New Jersey Motor Truck Assn.
P. 0. Box 160
E. Brunswick,  N. J. 08816

-------
STATE TRUCKING ASSOCIATIONS
Mr. J. 0. Larson
Managing Director
New Mexico Motor Carriers
  Assn., Inc.
P. 0. Box 25266
Albuquerque, N.M.   87125

Mr. Frank Scotto
Executive Director
New York Motor Truck Assn.
Ill Forth Avenue
New York, N.Y.  10003

Mr. J. T. Outlaw
Exec. Vice President
North Carolina Motor
  Carriers Assn., Inc.
P. 0. Box 2977
Raleigh, N.C.  27602

Mr. Joel Melarvie
Managing Director
north Dakota Motor Carriers
  Assn., Inc.
110 Third Street
Bismarck, N.D.  58501

Mr. Donald B. Smith
Managing Director
Ohio Trucking Association
Neil House Hotel
Columbus, Ohio  43215

Mr. Vince Robinson
Exec. Vice President
Associated Motor Carriers
  of Oklahoma, Inc.
P. 0. Box 14607
Oklahoma City, OK  73114

Mr. Robert R. Knipe
Managing Director
Oregon Trucking Assn., Inc.
720 Northeast 12th Avenue
Portland, OR  97232

Mr. William F. Richardson
Executive Vice President
Pennsylvania Motor Truck Assn.
711 Telegraph Road
Harrisburg,  PA  17101

-------
 STATE  TRUCKING  ASSOCIATIONS
Mrs.  L. M.  Daly
Secretary-Manager
Rhode Island  Truck  Owners
  Association, Inc.
49 Weybosset  Street
Providence, RI   02903

Mr. Samuel  L. Boylston
General Manager
Motor Transportation Assn.
  of  S. C., Inc.
2425  Devine Street
Columbia, SC  29205

Mr. CharJes Ingersoil
General Manager
Assoc. Motor  Carriers,  Inc.
  of  South Dakota
100 North Phillips  Avenue
Sioux Falls,  SD  57101

Mr. Robert Pitts
Manager
Tennessee Motor Transport Assn.
212 Capital Boulevard
Nashville, Tenn.  37219

Mr. Terry Townsend
Executive Director
Texas  Motor Transportation
  Assn., Inc.
P. 0.  Box 1669
Austin, Texas  78767

Mr. Otis Winn
Managing Director
Utah Motor Transport Assn.
P. 0.  Box 686
Salt Lake City,  Utah  84110

Mr. James Finneran
Executive Manager
Vermont Truck &  Bus Assn.
P. 0. Box 97
Montpelier, VT  05602

Mr. E. H.  Williams, Jr.
Executive Vice President
Virginia Highway Users
  Association, Inc.
P. 0. Box 1397
Richmond,  VA  23211

-------
STATE TRUCKING ASSOCIATIONS
Mr. William E. Hicks
Managing Director
Washington Trucking Assns.
4101 Fourth Ave., South
Seattle, Washington  98134

Mr. Harold Gainer
Managing Director
West Virginia Motor Truck
  Assn., Inc.
P. O. Box 4416
Charleston, W. Va.  25304

Mr. John P. Varda
General Manager
Wisconsin Motor Carriers
  Association
125 W. Doty Street
Madison, Wise.  53703

Mr. L. E. Meredith
Managing Director
Wyoming Trucking Assn., Inc.
Box 1889
Casper, Wyoming  82601

Mr. Camille Archambault
Executive Vice President
Trucking Assn. of Quebec
8575 Pascal Gagnon
Montreal, Quebec
Canada  HIP 1Y5

-------
3.  INDEPENDENT TRUCKING ASSOCIATIONS

-------
LIST OF INDEPENDENT TRUCKERS1 ORGANIZATIONS
Alabama Independent Truckers Asso-
  ciatiqn. Inc
J O Arnold
Rt H, Box 430
Tuscumbia Alabama 35674
(205)381-1750

American Owner Operators  Inter-
  national. Inc
Ted Gordon
1301 Anthony Wayne Bank Building
Fort Wayne. Indiana 46802
(219) 743-9777

Arkansas Independent Truckers Asso-
  ciation
Chuck Honey
Box 636
Prescott Arkansas 71857
(501)887.6661

Association of Independent Owner-
  Operators
G Ralph Grago
P 0 Box 2239
Sante Fe Springs, California 90670
(213)941-5781

California Dump Truck Owners Asso-
  ciation
301 E Pomo-12 3!vd
PO Sot 2'5
Monterey Park, California 91754
(213)726-7806
(213)685-4153

Central Iowa Independent Truckers
Dick Ross
Oes Mcmes, Iowa 50311
(515) 285-8331
(515) 266-3202

Chicago Truck Drivers Union (Inae-
  pendents)
Dan LaBotz
Chicago, Illinois
(312) 528-7357

Council ol Independent Truckers
Charles Piazza/Les Salsgiver
P O Box 58
Westfield Center. Ohio 44273
(216) 322-8553

Eastern Shore  Independent Dump
  Truckers Association. Inc
Bill Walter
Maryland
(302) 742-2580

Diesel Drivers International
Prince David Fmlayson
Baltimore, Maryland 21221
(301)686-8003

Florida Owner Operators Association
Chet Wesbrook
P.O. Box K 168
Land O'Lakes, Florida 33539
(813)996-2837

Fraternal Association of Steel Haulers
Bill Hill
Pittsburgh. Pa
(412) 322-3608

Independent Truckers Association of
  Northeast Pa.
Leonard Marchines
P.O Box 39
Dunmore. PA. 18512
(717) 489-3254

Kentucky-Indiana Independent Truck-
  ers
Doug Leatherbury
P O. Box 27
Memphis. Indiana 47143
(812) 246-3641

Middletown Truckers Group
Harold Kellis
Ohio
(513) 746-9582

Michigan Exempt Carriers Association
Bob Gebhart
Michigan
(616) 873-4087
 Midwest Truckers Association
 William Schulte
 2715 No. DirKson Parkway
 Springfield. Illinois 62702
 (217)525-0310

 National Agricultural Transportation
   League
 Buck Buchanan
 P O Drawer 960
 Umatilla. Florida 32784
 (904) 669-4220

 National Council of Independent
   Truckers
 Everett Henn
 Michigan
 (616)854-1173

 National Federation of Milk  Haulers
   Associations
 Rod Tyler
 Michigan
 (616)327-6203

 National Women's Trucking  Associ-
   ation
 Jean Sawyer
 40 Pendleton St
 Charleston, South Carolina 29403
 (803)577-3018

 Natural Resource Transporters
 Charles Thompson—Lawyer
 Suite 933
 Frank Nelson Building
 Birmingham. Alabama 35203
 Of flee (205) 254-3216
 Home (205) 822-9677

 North American Owner Operators
 George Lavender
 P 0 Box 988
 Fort Wayne, Indiana 46801
 (219)422-2511
 (219)749-5258

 North Carolina Truck Drivers Associ-
   ation
 Dewey Dove
 Box 175
 Bladenboro, North Carolina 28320
 (919) 863-3396

 Ohio Dump Truckers Association
 Bud Durst
 Ohio
 (614) 491-7872
 (614) 491-0280

 Owners and Drivers Club of Ohio
 George Rynn
 Ohio
 (216) 825-7895/96

 Owner-Operators and  Independent
   Drivers Association of  America
 Al Hannah
 P.O. Box 88
 Oak Grove. Missouri 64075
 (816)229-6396

 Southeastern Independent Truckers
   Association
 David L George
 Suite 520
 79 Commerce St
 Montgomery, Alabama 36104
 (205) 263-1046

 Southwestern Michigan Independent
   Truckers
 James Woods
 (616) 349-8848

 Tennessee Truck Drivers Association
   Darrel Lyons
   Box 146
   Elizabethton. Tennessee 37643
   (615)542-6210

   Truckers for Justice
   Joe Hememann
   New Jersey
   (201)261-5348

 United Independent Truckers Associ-
   ation of the Southern Tier
 John N Bump
 New York
 (607) 648-3692

-------
4.  TRADE JOURNALS

-------
 Thomas F. Dillon
 Transportation Editor
 Purchasing Magazine
 199 Joy Cee Court
 Middleton, New Jersey  07748

 Victor Riesel
 30 E. 42nd Street, Suite 1906
 New York, New York  10017

 John Kushnerick
 Editor
 Motor Age
 Chilton Way
 Radnor, Pennsylvania 19089

 Lee Stillwell
 Scripps-Howard, Room  1200
 777 14th Street NW
 Washington, D.C. 20005

 Omcr Henry
 Truck Topics Magazine
 8830 Sudbury  Road
 Silver Spring, Maryland  20901

 Editor
 Transportation Engineer
 911 West Big Beaver Road
 Troy, Michigan 48084

 John Shannahan
 Publisher
 Farm to Market Trucker News
 903 Cornelia
 Sioux City, Iowa  51106

 Dispatcher Dan Reports
 1375 Old Mill Road
Lake Forest, Illinois 60045

Truck Driver Magazine
6923 Chippewa Street
St. Louis, Missouri 63109
 Gary Macklin
 Editor
 Refrigerated Transporter
 Tunnell Publications
 1602 Harold Street
 Houston, Texas 77006

 Pacific Traffic
 2230 Big Ranch Road
 Napa, California  94558

 Paul G. Ingram
 Editor
 Bus & Truck Transport
 481 University Avenue
 Toronto, Ontario
 Canada

 Viola V. Anderson
 Executive Director
 The Anderson Group, Inc.
 Box 508
 Madison, New Jersey  07940

 Mitchell Krause
 CBS News
 524 West 57th Street
 New York, New York  10019

 John McCullough
 Editor
 Distribution Worldwide
 Chilton Way
 Radnor, Pennsylvania  19089

 Traffic World
 815 Washington Building
 Washington, D.C.  20005

W. H.  Hooker
 Editor
American Motor Garner
 104 Hemlock Dnve
Marietta, Georgia  30060

-------
Joe Evancho
Payload for Chevrolet
Seco Publishing Co.
30400 Van Dyke
Warren .Michigan  48093

Brenton C. Schultz
Marketing Programs Manager
Diesel & Gas Turbine Worldwide Progress
P.O.  Box 7406
Milwaukee, Wisconsin  53213

Emil Stanley
Editor
Fleet Management News
300 W. Lake Street
Chicago, Illinois 60606

G. R. Toedman
Editor
Mid-West Truckman
1101 Topcka Avenue
Topeka, Kansas 66612

Commercial News
3181 Fernwood Avenue
Lynwood, California 90262

Truck Tracks
P.O. Box 1575
Lake Grove, Oregon 97034

Phil  Moran
Editor
Transporte Modemo
10 River Street
Stamford, Connecticut 06904

Cliff Gromer
Automotive Information Council
666  5th Avenue
New York, New York  10009
Bernie Swart
Managing Editor
Fleet Owner
1221 Ave. of the Americas
New York, New York  10036

James Winsor
Editor
Commercial Car Journal
Chilton Way
Radnor, Pennsylvania  19089

Daniel G. Pennington
Government Relations
Rubber Manufacturers Association
1901 Pennsylvania Ave., NW
6th Floor
Washington, D.C. 20006

W. H. Raiford
Editor
Southern Motor Cargo
1509 Madison Avenue
Memphis, Tennessee 38104

Robert Finlay
Editor
Automotive News
965 E. Jefferson Avenue
Detroit, Michigan 48207

James D. Moss
Editor-Publisher
Heavy Duty Fleet Distribution
2751 Lake Cook Road
Deerfield, Illinois 60015

Sheldon Fitterer
Stanley  Publishing Co.
300 West Lake Street
Chicago, Illinois 60606

-------
Chris Lackey
Open Road Magazine
1015 Florence
Fort Worth, Texas 76102

Kent Powell
Editor
Heavy Duty Trucking
BoxW
Newport Beach, California  92663

Martin Trepp
Editor
Northwest Motor
83 Columbia Street
Seattle, Washington 98104

James E. Jones
President
Diesel Equipment Supt.
80 Lincoln Avenue
Stamford, Connecticut 06904

Lowell E. Perrine
Managing Editor
Traffic Management
205 E. 42nd Street
New York, New York  10017

Paul Townsend
Editor
Long Island Commercial Review
303 Sunnyside Blvd.
Plainvicw, New York  11803

Jean V. Strickland
Chilton Publications
1093 National Press Building
Washington, D.C. 20004

C. R. Don Sutherland
Modern Bulk Transporter
4801 Montgomery Lane
Washington, D.C. 20014
John Spencer
Executive Editor
Handling & Shipping
614 Superior Ave., W
Cleveland, Ohio 44113

Jack Walsh
Automotive News
965 E. Jefferson Avenue
Detroit, Michigan 48207

Jim Dunlap
Editor
Heavy Truck Transportation
1155Waukegan Road
Glenview, Illinois 60025

Truck Trends
3950 N. Lake Shore Drive
Chicago, Illinois  60613

Chns Lackey
Editorial Director
Open Road
1015 Florence Street
Forth Worth, Texas 76102

Go Transport Times of the West
1240 Bayshore Highway
Burlingame, California 94010

Editor
Automotive Industries
Chilton Way
Radnor, Pennsylvania  19089

Editor
Motor Magazine
723 New Center Building
Detroit, Michigan 48202

Editor
Motor
250 W. 55th Street
New York, New York  10019

-------
Editor
Auto News of Pacific Northwest
7525 SE Lake Road, Room  12
Milwaukie, Oregon 97222

Sidney S. Abelson
Public Relations Chairman
Greater New York Tire Dealers
 & Rctreaders Association
121-15 Liberty Ave. - Richmond Hill
Queens, New York 11419

Roger Muehl
Editor
FWD News
Clintonville, Wisconsin 54929

Greg Stark
Editor
Dana Corporation
P.O. Box  1422
Reading, Pennsylvania 19603

Paul Schenck
Editor
Trailer-Body Builders
1602 Harold Street
Houston,  Texas 77006

William Toderan
Manager
Plant Communication  Programs
Rockwell International-Automotive Group
911 West  Big Beaver
Troy, Michigan 48017

Bruce Wadman
Editor
Diesel & Gas Turbine Progress
P.O. Box  7406
Milwaukee, Wisconsin  53213
David Allen
Editorial Department
Star Ledger
Star Ledger Plaza
Newark, New Jersey 07101

Francis O'Connell
Transportation Writer
Buffalo Courier Express
787 Main Street
Buffalo, New York  14240

Helen Kahn
Bureau Chief
Automotive News
525 National Press Building
Washington, D.C. 20004

Roy Covington
Transportation Writer
Charlotte Observer
P.O. Box 2138
Charlotte, North Carolina 28233

Frank Bassett
Mid Continent, Inc.
P.O.Box  1370
West Memphis, Arizona 72301

Harold Gold
Editor
New York Journal of Commerce
99 Wall Street
New York, New York  10005

Earl T. Monahan
64 Edmonds Street
Rochester, New York  14607

Rebecca Sammartino
USDA AHSTSB
14th and  Independence, SW
Washington, D.C. 20250

-------
Brian Moskal
Chicago Regional Manager
Industry Week
400 N. Michigan Avenue
Chicago, Illinois 60611

Richard Witkin
Transportation Editor
New York Times
229 West 43rd Street
New York, New York  10036

Claude M. Wolfe
Editor and Publisher
C.W. Publishing Company
P.O. Box 184
Sharpsville, Pennsylvania 16150

August Gribbin
Transportation Writer
National Observer
11501 Columbia Pike
Silver Spring, Maryland 20910

Stanley Latham
First National Bank of Chicago
Trust Department, 16th Floor
1 First National Plaza
Chicago, Illinois 60690
Ernest Finan
Transportation Writer
165 E. Maujer Street
Valley Stream, New York 11580

Ed Lincoln
Director, Public Relations
Pennsylvania Highway
Information Association
800 North Third Street, Suite 501
Harrisburg, Pennsylvania 17102

Bradley Martin
Baltimore Sun
501 N. Calvert Street
Baltimore, Maryland 21203

Ralph Varnum
Transportation Editor
Kansas Citian
620 Tenmain Center Building
Kansas City, Missouri 64105

-------
5.   TRUCKERS'  RADIO STATIONS

-------
  TRUCKERS'

RADIO STATIONS
 KWKH - 1130 kc
 P. 0. Box 1130
 Shreveport, La.  71120
 318/222-8711
 KLAC - 570
 Metromedia Radio
 5828 Milshire Blvd.
 Los Angeles, California
   90036
 213/977-0110

-------
15. GUIDELINES FOR MEDIA RELEASES

-------
                                   SECTION 15

                      GUIDELINES FOR MEDIA RELEASES
     Since most communications with the various media should be coordinated with the
 respective regional public affairs office, specific instructions may not be practical.  However,
 there are some general guidelines that should be taken into consideration.
     Planning an effective multimedia campaign takes a great deal of time, effort, and
 money  The media for such a campaign are: radio, television, and the press.

 PRESS
     The press is in the news business. The environment is news.  Consider these approaches:
     Get to  know the press   Make an appointment to see the editor, managing editor, or
 city editor of your newspaper and  the news director of your local television and radio sta-
 tions. If you have any community leaders or other well-known individuals in your member-
 ship ranks, try to have one or two of them accompany you on the visit.
     Tell the press about your organization's objectives, programs and members  Explain
 how you might be able to help them from time to time by interpreting the technical and
 scientific jargon of pollution  control into lay language, by evaluating the success or failure
 of pollution  control plans, by alerting them when key environmental decisions are forth-
 coming, by giving them newsworthy tips, etc.
     Ask if there's  particular editor or reporter you should contact when you have a poten-
 tial news story.  Give  them the name and telephone number of the person in your organization
 whom they can contact.
     Ask for editorial support as well as coverage in news columns. Leave them with a
 brief (preferably one-page typewritten) description of your organization and its programs
and add them to the mailing list for your newsletter, magazine, etc.
    There's no substitute for this initial personal contact.  It gives you and the press an
opportunity  to get to know each other.  It gives you the opportunity to establish your
credibility.
    Maintain your credibility. This is vital for continuing good relations with the press.
Your group must be responsible, responsive and knowledgeable in dealing with the press at
all times. Don't make statements or accusations you cannot support. Don't be evasive. If"
you don't know the answer to a question, say so and offer to get it and call back. Then do
so, with the answer or with a  frank statement that you don't know or couldn't get the
answer.  Don't guess.  Don't speculate. If you're telling the press something off the record,
make  it clear that you don't want to be quoted.  But don't use the off-the-record cover to
peddle false or inaccurate information.
                                      15-1

-------
     Learn press deadlines  Don't call them at deadline time unless you've got a truly "hot"
item. Time your press releases to meet their deadlines.
     In your press releases and conversations with the press, avoid the jargon of pollution
control.  Unless the reporter covers the environment full-time, chances are you know more
about the subject than he does  Be helpful by talking more about the subject than he does.
Be helpful by talking and writing plainly.
     Don't issue press releases or hold news conferences unless you really have something
to say  If you hold  a press conference, have a release and background material available and
give the press a chance to go over it before the conference begins. Don't waste the press's
time by simply rehashing the press release in your oral presentation.  Allow plenty of time
for questions.  If you really have nothing to add to the release, or if the subject doesn't lend
itself to questioning, you shouldn't hold a press conference. And don't schedule press con-
ferences at deadline times or in competition with other local major news developments.
     Don't tell the press what to print or broadcast  That is their business and their decision.
And don't expect the  press to print or broadcast every word in your press releases. Settle
for a part of the  story.
     When you issue a press release, deliver it personally if at all possible  If you have to
mail it, call and alert the press that a release is in the mail and brief them on the content.
Don't try to read the release to them unless they ask you to.  Whenever possible, get  the
release to the press at  least one or two days before the release data.  (This will not be possible
under certain circumstances, of course - such a statement from your group in  response to
a control agency action, a polluter's action, a legislative action, etc.)
     If an officer of your organization is making a speech somewhere, send a copy to the
press at least a day or  two before, with a press release or cover note.  Mark the release and
the speech for release  at the time and date it will be given.
     Don't argue with the press  If you think you have a grievance, discuss it with them
privately and rationally. Don't attack the press. If you have an honest disagreement on a
public policy, or an editorial opinion they've expressed, present your views in a letter to
the newspaper editor.  If it's a radio or television station, ask for an opportunity to reply
through a taped editorial comment, broadcasting's version of the letter to the editor.
     Be sure of your facts.  If you mislead the press, you can destroy your credibility and
public acceptance.  And consequently, your public ability to influence public opinion,
government and  industry
     Be resourceful  Look  for opportunities for your organization and its programs to
become part of local news events, not necessarily centered on the environment and thereby
receive valuable visibility.

GETTING ON THE AIR
     The powerful forces of public information present opportunities for spreading the
environmental message such as through a good local  feature story.
     Under the "fairness doctrine," the Federal Communications Commission  requires radio
and television stations to air both sides of controversial public issues.  Environmental advo-
cates should keep this in mind, for they may be able to obtain broadcast time to rebut a
                                       15-2

-------
program or commercial that doesn't present both sides of an environmental issue. (For
further information on the fairness doctrine, write the Citizens Communications Center,
1812 N St., N.W., Washington, D.C. 20036.)
    Many cities have at least one all-news radio station.  Using news service material and
their own staffs of reporters and editors, these stations broadcast only news (and commercials,
of course).  News items are often repeated fairly frequently, depending on each station's own
newsgathering resources. These stations should not be overlooked, for their heavy demand
for news makes them likely to want to know what newsworthy groups are doing.  They may
be interested in feature items.  If there's an all-news station in your community, contact the
program director. Offer to help  keep him up to date on the environmental scene. Suggest
features, such as periodic reports on the community's environmental quality  what major
sources of pollution are doing to clean up, what control agencies are doing, and what special
groups such as youngsters are doing.
    Another possible approach  to use is public service time. The FCC requires commercial
radio and television stations to make available a certain amount of free time to community
organizations and causes.  This can range from airing short spots at commercial breaks extol-
ling worthwhile objectives, such  as "support clean air week" or "don't be a litterbug," to
programs devoted to community problems and community organizations. Contact local
broadcasters and find out if and  how you can get public service time.
    Public (or educational) radio and television stations should also be contacted  They
devote considerable time to community problems and programs.  They seek to explore com-
munity problems and to provide a forum for community organizations. The state of your
community's environmental health and what's being done to improve it might be the kind
of subject they would like to cover, occasionally or perhaps even as a monthly public report,
or even as a daily "progress" report.
    Still another broadcast resource that should be tapped is the college and university
radio station.  Student broadcasters are often  quite sympathetic to environmental improve-
ment and should be involved in your projects.
    But how do you get on radio or television? Try the direct approach.   With a few
definite program ideas in mind,  visit the  station manager or program director at the com-
mercial, public and college radio and  television stations in your community.  Discuss
your ideas.   Ask about public service time  Arrange to be invited to a talk show, where
you would  have an opportunity to discuss the noise pollution  problem in depth.  If the
answer is yes, what do you do then?  How do you go about putting together a suitable
show?  The radio or television station may provide assistance.  But your  group should
keep these ideas in the event you  find yourself with a block of public service time to fill.
     1.   The public already knows there are  environmental problems. Simply "viewing
         with alarm" is no longer newsworthy or informative or educational  The public
         is interested in  action. So is your group; that's why you  exist.  So zero in on
         specifics.  Here are some examples:  Have noise deadlines been set for the major
         pollution sources in your community?  If yes, are the deadlines being met?  If
         not, why not?  What are the prospects for a quieter environment in your com-
         munity? What are the obstacles?  What can and should be done about them?
         What can the public do  to help?
                                      15-3

-------
     2.   The program should be a balanced presentation of whatever environmental
         problem  or problems you're discussing.  Your organization might host the
         broadcast.  But you should include spokesmen for the control agency and
         the polluters.  This will help expose the audience to all points of view - and
         will help you to establish yourselves as a responsible, respected organization.
     3.   The program should give the audience a chance to participate  Provide time
         for questions from  the audience (if the program is live), or for people to call
         in and ask questions, or both.
     4.   The program should be as concise and as entertaining as possible.  Avoid long
         speeches, monologues,  "lectures" and formal debates if you want to avoid
         losing your audience
     5.   Consider the audience  of the station. For example,  in Fort Wayne, Indiana,
         there  are lots of people in the trucking industry; or in an  area where  a new
         interstate highway is being constructed interest will be high.
         The size  of the station is also important   Suggest noise pollution features to
         small  stations.
     6   Explain the importance of subject matter simply in non-technical language.
     7.   The program should attempt to suggest specific  things that people can do to
         help the  cause of better local environment.  For example'  give them a tele-
         phone number to call (your group's or the control agency's)  if they see a sus-
         pected violation  of an  environmental law. Give  them the  time and place of
         important public hearings.  Give them names and addresses of public  officials
         to write  to on pending environmental desisions,  bills, appropriations, etc.  If
         you're discussing noise pollution, have a physician to explain what health pre-
         cautions  people should take in  the event of a noise pollution episode.
     8.   While you might consider the program your show, the station is responsible
         for what is aired   Make suggestions, of course.  But respect the management's
         rights and professional experience.
     9.   If it's a television program, try  to provide visual material - films and still
         photographs - or help the station find suitable locations if it prefers  to shoot
         its  own film   Try to reach the viewer through both  sight  and sound.
    10.   The program should relate environmental noise pollution problems to people.
         Without  scaring them into a sense of futility and hopelessness, try to dramatize
         the effects of noise pollution on health, on  recreation, on the economy, on the
         quality of life, etc.   And try to give a feeling that things can be done. Others
         have succeeded,  why not here?
    11.   The program should be credible. Participants should know what they're talk-
         ing about.  If someone doesn't  know the answer to a question, there  should
         be  no fudging.
     These few  guidelines only skim the surface. The possibilities of using radio and
television are limited only by the imagination  of those who plan and put on the program.
As many organizations do, your  group should seek all possible assistance from members,
or sympathetic  outsiders, who are professional communicators.
                                      15-4

-------
16. EPA-DOT NEWS RELEASES AND
    PUBLIC ANNOUNCEMENT

-------
               SECTION




                    16



  ERA-DOT  NEWS  RELEASES



AND  PUBLIC  ANNOUNCEMENTS

-------
1.   EPA PRESS RELEASE ON PROMULGATION OF NOISE



    EMISSION REGULATIONS FOR INTERSTATE



    MOTOR CARRIERS








                       NOV.  1974

-------
                      INDEX
1.  EPA Press Release on Promulgation  of
    Noise Emission Regulations  for  Interstate
    Motor Carriers                                    Nov. 1974

2.  Public Service Announcements  for Use  by
    Radio Stations on the Noise Emission
    Regulations                                       June 1975

3.  Public Service Announcement for Use by
    Television Stations on the  Noise Emission
    Regulations                                       June 1975

4.  Potential Questions and Answers Regarding
    the Noise Emission Regulations                     April  1975

-------
               FINAL NOISE EMISSION REGULATIONS
                FOR INTERSTATE MOTOR CARRIERS
     The Environmental Protection Agency has announced the
issuance of regulations for the control of noise emissions
froii; vehicles operated by interstate motor carriers.  The
proposed regulations were published in the Federal Register
on July 27, 1973, as required under Section 18 of the Noise
Control /»ct of 1972.  Final regulations will be published
in the Federal Register within the next few days.  This is
the first final standard-setting action by the Agency under
authority of the Act.

     The new standards, which apply to all vehicles over
10,000 Ib. gross vehicle-weight rating or gross combination
weight rating by interstate motor carriers, take into account
the best available noise reduction technology and the cost of
compliance within the one-year time period for conformance
wits'' the standard by interstate carriers.

     Tr.ir, regulation is the first significant Federal step in
a series of actions to reduce highway noise.  This standard,
applicable to ir-use vehicles operated by interstate carriers,
will have an impact within one year on reducing highway
traffic noise.  In conjunction with the more stringent new
medium and heavy-duty truck noise control regulations just
proposed by the Agency (see fact sheet on Noise Emission
Standards Proposed for New Trucks), further traffic noise
reduction will be accomplished in a systematic time phased
mariner to permit application of available technology while
keeping the costs to meet the standards as low as reasonably
possible.

     The standards are expressed in A-weighted decibels.   A
decibel is a numerical  expression of the relative magnitude
of sound.  "A-weighting"  is a method of numerical  adjustment
to reflect impact of noise on the range of human hearing.

     As new control  retrofit technology is developed and can
be applied at reasonable  cost, the interstate motor carrier
regulations will  be revised accordingly.   Further revision of

-------
                              -2-

the interstate motor carrier regulations  will  be made to
assure that new trucks manufactured in  accordance with the
more stringent new product noise control  standards (see
fact sheet on Noise Emission Standards  Proposed for New
Trucks) will not be degraded acoustically during inservice
operation by interstate carriers.


THE STANDARDS

     Under the new standards, noise emissions  from the vehicles
subject to the regulations may not exceed:

     * 90 dB(A) at 50 feet in zones with  speed limits above
       35 miles per hour;

     * 86 dB(A) at 50 feet in zones with  speed limits at or
       less than 35 miles per hour;

     * 88 dB(A) at 50 feet under a stationary  engine runup test.

     The standards also provide for a visual  inspection of exhaust
systems and tires.  Tires containing pockets which trap air while
in contact with the road surface are restricted under the new
regulations unless a carrier can demonstrate  compliance with the
90 dB(A) standard using such tires.  Vehicles  must have effective,
continuously operating muffler and exhaust systems.


ECONOMIC IMPACT

     It is anticipated that 7 percent (70,000) of the one million
motor vehicles presently operated  by motor carriers engaged in
interstate commerce to which the regulations  are applicable, will
require some degree of retrofit to comply with the regulations,
according to EPA Administrator Russell  E. Train.  Usually, a
muffler or different tires will suffice.   In  some cases, the
cooling fan will require modification.   The average expected
cost per vehicle needing retrofit  treatment is $135; total costs
to the industry are not expected to exceed $10 million.


PREEMPTION

     Section 2 of the Noise Control Act says  that State and
local governments have the primary responsibility for noise
abatement and control.  However, it was recognized that Federal
action is needed to deal effectively with major noise sources
engaged in interstate commerce and which, therefore, require
uniform national treatment to facilitate  such  commerce.

-------
                              -3-

     State and local  jurisdictions  may  not adopt or enforce
noise control  regulations  of the noise  sources  covered by
this interstate motor carrier regulation unless  such State
or local  regulations  are identical  to the Federal  regulations.
Federal  preemption for interstate  motor carrier  noise control
regulations (Section  18 of the NCA, 1972) is  significantly
different from the preemptive Federal authority  for newly
manufactured trucks (Section 6 of  the NCA, 1972) which leaves
to State and local jurisdictions the authority  to establish
and enforce controls  on levels of  noise emissions resulting
from the operations of such new trucks.  However, States and
localities are strongly urged to adopt  regulations applicable
to interstate motor carriers which are  identical to the Federal
standards and to participate, through their enforcement capa-
bilities, in achieving an  effective nationwide  enforcement
program.  It is recognized, however, that in  some areas
standards or controls on levels of environmental noise, or
control, license, regulation, or restriction of  the use, operation
or movement of any motor vehicle to which these  regulations are
applicable may be necessary or desirable based  on special local
conditions, as long as such action is determined not to be in
conflict with the Federal  regulations.   In these cases, appli-
cation shall be made to the Administrator for such determination.
The procedures for applying for such determination will be
published in the Federal Register within the  next four months.


ENFORCEMENT

     Under the law, the Secretary  of Transportation, after
consulting with the Administrator of EPA, is  responsible for
assuring compliance with these standards.  State and local
jurisdictions employing identical  standards,  are encouraged
to act as independent enforcement  agencies.


 NOVEMBER  1974

-------
2.   PUBLIC SERVICE ANNOUNCEMENTS  FOR USE



    BY RADIO STATIONS ON THE NOISE



    EMISSION REGULATIONS










                       JUNE 1975

-------
Public Service Announcement
NOISE PROGRAM
30 Second Radio Spot
                        TRUCK NOISE


    Here's a special message from the U.S. Environmental

Protection Agency for interstate motor carriers and

particularly owner-operators.


    Enforcement of a new Federal EPA exterior noise control

law will begin soon.  That law will help you by giving

truckers just one set of standards for noise control that

will apply throughout the 50 states.


    But your rig must comply with this law by October 15.

The noise level oi your rig can be measured in many shops

at a low cost or even for free.  Do it now while you still

have time to shop around for ti  -. . jst deal in case you need

work to quiet that muffler, fan, engine or tires.

-------
Public Service Announcement
NOISE PROGRAK
60 Second Radio Spot
                        TRUCK NOISE


    Enforcement of a new Federal lav; important to interstate

motor carriers takes effect soon.  Under that law there will

be just one set of national standards for your rig to meet

all exterior noise control laws.


    There'll be one noise law and one set of standards for

testing noise.  That way you won't have a whole new set of
  /•_«•   •
        to worry about every time you cross a state line.
    But you have to be ready for it.  You can have your ric

tested for noise now...a lot of shops will do it for a very

low cost, or even for free.  That might not be the case after

the law takes effect October 15, 1975.


    And if you do it now you'll have time to snop around for

the best deal in case you need work done to quiet your

engine, fan, exhaust or tires.


    If you want more information to help you meet this new law

you can get it by writing:  Truck Noise, EPA, Washington, D.C.

20460, or ask any BMCS man.

-------
Public Service Announcement
NOISE PROGRAK
60 Second Radio Spot
                         TRUCK NOISE


    Enforcement of a new Federal EPA law begins October 15, 1975

It sets one national standard for controlling tne exterior

noise of interstate motor carriers.


    Truckers and other owner operators will need to be ready

for it by checking noise levels of engines, fan, tires, muffler.


    A test with sound level meter will do the job—it's a

test you can get at low cost in hundreds of shops.


    But  -ou can do part of the test right now; in facr part of

what the BMCS will do come October.  It's not noise measurement

or metering or listening for noise.  You look for it.      _he

muffler has a hole in it, or tailpipe is rusted out, or if you

have pocket retreads, that'll mean noise.


    This law is not complicated.  Matter of fact it simplifies

things with one Federal standard instead of different noise

control laws in every state.


    So, speaking of making things easy...make it easy  on

yourself and get your rig checked soon.


    If you want more information to help you meet this law

you can get it by writing:  Truck Noise, EPA, Washington,  D.C.

20460.

-------
Public Service Announcement
NOISE PROGRAM
30 Second Radio Snot
                        TRUCK NOISE


    Here's a special message from the U.S. Environmental

Protection Agency for truckers and other interstate motor

carriers particularly you owner-operators.


    Enforcement of a new Federal EPA exterior noise control

law begins on October 15, 1975.  It sets uniform standards
   r % -  *                                     ._•' .
for noise «*"!«• rrrt on rolling or stationary &ryvtri~ in all

50 states.


    To get information on what you need to do to comply and

how to go about ;: write:  Truck Noise

                           EPA

                           Washington, D.C.  20460

or ask any BMCS man.

-------
3.   PUBLIC SERVICE ANNOUNCEMENTS FOR USE BY



    TELEVISION STATIONS ON THE NOISE



    EMISSION REGULATIONS
                    JUNE 1975

-------
IV I'UULIC SERVICE AFJNuu.;CEMEIJl ;  30  SECONDS:  LOCAL  NuJ
LAl.'L; OflAC
                  LU.il HL.
     VIDEO & EF>'
         AUDIO
LONG SHOT OF WASHINGTON        ANNCR:
MONUMENT.  SLOW ZOOM TO FLAGS
AT BASE.  MUSIC IN BACKGROUND--
PRETTY BUT PATRIOTIC.
 IT ALL BEGAN  200  YEARS  AGO.

 THE  FREEDOM OF  SPEECH,  THE  RIGHT

 TO PETITION THE GOVERNMENT,  TO

 PEACEFULLY ASSEMBLE.
PAN UP MONUMENT TO SKY,
AIRPLANE COMES INTO VIEW FROM
NATIONAL AIRPORT
THOSE RIGHTS HAVE  ONE  SIMPLE

FOUNDATION.
HOLD ON AIRPLANE, SFX UP
SOFTLY MUSIC UNDER
SFX LOUDER, AIRPLANE FLIES
OVER.  MUSIC BARELY AUDIBLE
(RAISES VOICE LEVEL TO  BE HEARD)


AMERICANS MUST BE ABLE  TO TALK TO

EACH OTHER...


(RAISES VOICE LEVEL AGAIN)
SFX LOUD.  WIPE TO TRUCK/SFX
.. .BUT WE CAN'T TALK TO EACH
OTHER...
WIPE TO OACKHAMMER/SFX
                                       (RAISES VOICE AGAIN)
                                       ...IF WE CAN'T HEAR EACH OTHER
SUDDENLY, ALL QUIET, CUT BACK
TO MONUMENT, LONG SHOT
FIND OUT WHAT'S BEING DONE

ABOUT NOISE POLLUTION IN YOUR

COMMUNITY.
SUPER EPA ID

-------
TV i-Ui'.LlC SEKViOL AI
-------
4.  POTENTIAL QUESTIONS AND ANSWERS REGARDING



    THE NOISE EMISSION REGULATIONS







                        APRIL 1975

-------
           motor carrier

              regulation


How  does the new FederaJ Interstate  Motor
Carrier Regulation on noise emissions affect me?
     If vou  own  a  truck, bus or  other motor
     vehicle  having  a  GVWR/CCWR of more
     uun  I 0.000  fbs.  and arc engaged in intcr-
     SMI:  commerce, vour vehicle must not cx-
     ewj  the following  maximum  permissible
     evieriiv noise levels.
       •  ^.S dBA  (:jiiJ IT local -"i- T vch-cL

-------
              correcting

         noise  problems


If I hate a noise problem, what's the most likely
cause?
     Exhaust systems and cooling fans are  the
     most common high noise makers under sta-
     tionary  and low  speed conditions, at high-
     way speeds, tires frequently make  the most
     poise Other  sources which can add to  the
     total noise le\el are
       • engine (mechanical)
       • air intake system
       • transmission
       • auxiliary ep.r.r.e equipment
       • brakes
       • aerodynamic r'o*

Isn't im stock muffler quiel enough?
     Not necessarily  Heavy-duty motor \ehicle
     manuracturers ha'.e  not had  to  buiid  to
     scc-'iric  noise  ..•r'ission  standards.  Muf-
     rjrs  have often :<.^n  s^ivCi.u for ineir
     lc>«  cost,  appcjr.p.e sue. and hack pres-
     sure rather than •• r noise uuictiPv: anility
     Chock  muffler manufacturers  or  ois;nou-
     tors. they  can an-e  you mrormation about
     the  noise reduction  capabilities and other
     operational  features  ot  various  models
     wnen fined to specific engines You may
     also want  to investigate the addition of a
     turbocharger  to your  vehicle   Recent  in-
     dustry  test result1; show impressive  noise
     reduction  in  addition to fuel  savings and
     improved  engine penormance.

I understand cooling  fans can cause high noise.
How can I tell  if  this is  m> proWem, and what
can I do about  it?
     Coo"1"!! fans CJP cause lush noi>e  How-
     j1..r  niaimen.'.-.je M-.ops w:;h -!m>c  testing
     :awi!-..j> >houlj ?i  ib-e to tell it  this is
     ;o-.r problem   !'  vr  example  you  m-
     »'ai'cd  jspecul'1 cuici mufriers  lor >our
     p-.-t'cuijr jjvjn. ,L-'j the  triuA is si;ll  too
     '-. ".v ii -, hW '.   • -i" i in m.i1 nenl shroud
      ."•"ir   .lOiaitiPir'  'or  fan  ' T cL'.ir.'nce.
     -i  .'. -.-p,!;-  • •  ' - . ,..-vi:   r ~i >^'r>!-. a
     di".'r."ii hi.njj ..--'.":  k.mirmer  rnncnri-
     cations to cooling system-* should not be
     done without expert advict- You may want
     to  consider a temperature controlled fan;
     resultant  fuel  and cost  savmus are as  im-
     pressive as their noise reduction.

If my tires cause a noise problem at highway
speeds,  what  type  tire should I replace  them
with?
     This is a matter of judgment  based on
     your operational  requirements. Generally.
     tread  patterns with  non-vented  cavities
     (suction cups) produce unu-ually high noise
     levels. This condition exists in pocket re-
     treads and can rxxur in  otlvr Te'id designs
     with tire wear. Tebis show ih.it rib tires are
     quieter than many otner popular designs.
     Tire manufacturers  and dealers  can  give
     you guidance in  selecting:  quiet  tires that
     meet your specific requirements.
          advantages  of

        early compliance

Are there an> advantages  if I comply with  the
Federal noi.se standard before October 15,1975?
     Yes  You can benefit  in a number of wajs
     if \ou comply early For example:
       1  You  can  reduce the possibility of a
     fine for violation  of  motor vehicle  noise '
     regulations  in  the numerous  States  and
     local jurisdictions  that have current laws.
     (State and local authorities are not required
     to  wait  until October 15 to  enforce their
     noise standards)
       2. You  can take advantage  of courtesy
     noise measurements now offered by many
     component manufacturers and various Fed-
    eral, State  and  locul   authorities. An  un-
     hurried  thorough  involution  of  your
     principal  noise  prcolcm cmild save  >ou
     dollars
       3  You will have time to "shop around"
     for  the  best. Kw-co't  ;o!ii:vn  to your
     problem
       -}  YOJ  c.\i\  reduce youi  c.Ms of com-
     r'un.e ^>.  ei-eJi!1 .17 -••>i:i  ni. is'ircm.vMN
     and  j.'Tective  'viirx.. ir neeJed.  Ju-irv.;

-------
    norrr:il  maintenance  periods  instead  of
    ru.sh:n.i to meet a deadline
       5.  You may  sjve in fuel consumption
    and cost  and realize an increase in avail-
    able po*er where noise reduction steps are
    taken  that improve engine breathing  and
    cooling fan efficiency
       6 You can improve the public image of
    trucxers and  of the trucking industry.
       7  You can enjoy greater driving com-
    fon, productivity and safety.
            enforcement


Who will enforce the regulations?

    The Department  of  Transportation's  Bu-
    reau of Motor  Carrier Safety will handle
    enforcement at the Federal level  State and
    loc.il jurisdictions '.MII  also have enforce-
    ment responsibility.  The new  law requires
    that all noise regulations applied 10 motor
    vehicles involved in interstate  commerce
    be identical to the Federal regulation
             information

                     &

             assisiance


Where can  I get more  information about the
regulation?
     Contact any office  of the U.  S. Environ-
     mental Protection Agency or DOT/Bureau
     of Motor Carrier Safety Office  listed below
     by Regions served.  Also  your local main-
     tenance shop,  motor vehicle component
     manufacturers  and  either  State or  local
     hr^h'v.iy/ vehicle divisions should be  able
     to assist you.

Region 1 States: Connecticut. Maine. Massachu-
setts. NCA' Hampshire, Rhode Island, Vermont
bSR?\                DOT-BMCS
R.'om 21 '3             4 NoTUPikill Boulevjrd
JF:<  Fstl-Ml  Bu'M:"j     Deim.ir, NY   12054
Bailor M -»  U2203
Region 2 States: New jerse). N'ew York
L'SEPA                DOT HMCS
Room  9Ts             4 N,.rrrvf"  i M^u.tf'.-r 1
2h Federal P1 iza         Co! mar SV  12054
New Yorv.  M   100<)7

Region 3 States: Delaware. Mjr>i.r J.  PcnnsM-
vama.  \ irgima.  West  Virginia.   Disinci  01
Columbia
L'SEPA                DOT B\ICS
Room  225              Roon SI 6-A
Curtis  BmMirg          Federal Hi 'IJ.r.g
6th and Wjinti: Sireeis    31  Hoc-, r^ i"aia
Philadelphia. PA  19106   Bal.imor;. MD :i:oi

Region  4  States:  Alabama.  Co-, r.ia.  FloiJa.
Mississippi. North  Carolina  South  Carolina.
Tennessee.  Kentuck\
USEPA
Room Ifi9
1421 Peachtres Street
Aclania. O \. 3n3o9
DOT BMCS
Su.ie 200
!7:OPea;htr:e RoaJ N \\
Atlanta. C-\ ;\''<»)
Region 5  States:  Illinois. Indiaru. Ohio. Michi-
gan. Wisconsin Minnesota
L'SEPA                DOT BMCS
203 South Dearborn Street IS209 Souih Dix.e Hiahway
Chicago, it  6U604      HomeuooJ. IL  61)430

Region  6  States:  Arkan»n>. Louisiana. Okla-
homa. Texas. New Mexico
                                                                               DOT BMCS
                                                                               <19 T.n'or S.-ist
                                                                               Fort 'Ajrih TX  76102
USEPA
Room 1107
1600 Patterson Sireet
Dallas TX  75201

Region  7 States: Iowa, Kansa-,.  Missouri. Ne-
braska
USEPA                DOT BMCS
P35 Bait.mor; Street     P  O Bo\  7IS6
Kansas Cny.  MO  64108  Counfv C'u? Station
                      Kansas  Cuy. MO  64113

Region  8  States: Colorado,  Utah.  Wyoming,
Montana, North Dakota, South Dakota

USEPA                DOT'BMCS
Suite 900              Room 151. BuilJing 40
1S60 Linccnn Sireet      Denver  FiJeral Center
Denver. CO  80203      Denser, CO  80225

Region  9 States: Arizona, California, Nevada.

Hawaii
LSEPA                DOT BVCS
100 C.il-:orn-a S'rset     J5« G-".1:-. G le  A^i;
San Franciico. C A  ^-11! Box. 3n- "^
                      Sap. Franvi-vo CA  94102

Region  10 States: -\laska.  Idaho Oregon. NXa^h-
mgton
LSEP.A                Df.T 13MC^>
Room l!c             R. .-.-1-,:  M - -a\.% B'JJ
12(Mi M\tn \\si.ie        222>v>  \i •- i. -r 5,;.n
Sc.ill'.e \*A  -.-U'l      iV.- Tl, <*A   '"M4

-------
Oilier  nf  iSnisr Al) ilcinrnl and
I'S  I iniimiimiil tl I'roirclinn A
\\.isliinrf-Mi. IM . 211 IOC
(Illnl it  HII-IIM-S
l-riinlli  hit I'lliiitr UIL tllKI
                                Control /UV-571
              POSTAOE  AfJD r-rrs  fviu
ENVIRONMENTAL PI1OTECMOM  M".n\r.f
                                 cr/^  • ••;
              THIRD  CLASS HULK C-MI'

-------
17. MISCELLANEOUS

-------
            SECTION




                     1  7




MISCELLANEOUS

-------
          NOISE TEAM



      ENFORCKMENT SUMMARY
Heavy Trucks (6,000 GVW or More)
                                            SEMIANNUAL 1974
Speed
Zones
Over 35
35 or less
Total
Vehicles Vehicles
Measured in
Violation
127,093 1,360
14,821 207
141,914 1,567
Vehicles
Receiving
Enforce-
ment
Action
891
148
1,039
Vehicles in
Violation
as of % Modified
of Vehicles Exhaust
Measured
1.07% 34
1.40% 12
1.10% 46
Cause of Violations
Defective
Exhaust
179
42
221
Inadequate
Exhaust
655
92
747
Other
23
2
25
Passenger Vehicles
Speed
Zones
Over 35
35 or less
Total
Vehicles Vehicles
Measured in
Violation
296,718 5,756
113,414 1,900
410,132 7,656
Vehicles
Receiving
Enforce-
ment
Action
4,212
1,316
5,528
Vehicles in
Violation
as of % Modified
of Vehicles Exhaust
Measured
1.93% 3,444
1.67% 872
l'.86% 4,316
Cause of
Defective
Exhaust
695
399
1,094
Violations
Inadequate
Exhaust
67
40
107

Other
6
5
11
Motorcycles
Speed
Zones
Over 35
35 or less
Total
Vehicles Vehicles
Measured in
Violation
2,533 516
1,169 162
3,702 678
Vehicles
Receiving
Enforce-
ment
Action
351
129
480
Vehicles in
Violation
as of % Modified
of Vehicles Exhaust
Measured
20.37% 299
13.85% 88
18.31% 387
Cause of
Defective
Exhaust
31
19
50
Violations
Inadequate
Exhaust
21
20
41

Other
2
2

-------
                                   1973-1974 SEMIANNUAL

                                 NOISE SUMMARY COMPARISONS
                             Heavy Trucks (6,000 GVW or More)
              Vehicles Measured
Violations
 Vehicles in Violation as a
Percent of Vehicles Measured
                             Percent                   Percent
  Speed      1973     1974     of      1973     1974     of
  Zones    Jan-June Jan-June Change  Jan-June Jan-June Change
                                       Percent
                       1973     1974     of
                     Jan-June Jan-June Change
 Over 35     94,144  127,093 + 35%       774    1,360   +76%

35 of less   16,300   14,821 -  9%       158      207   +31%

  Total     110,444  141,914 + 28.5%     932    1,567   +68%
                         .90

                         .80

                         .80
              1.07  +]8.97o

              1.40  +75%

              1.10  +37.5%
                                    Passenger Vehicles
Vehicles Measured
Speed
Zones
Over 35
35 or less
Total
1973
Jan-June
188,827
153,371
342,198
1974
Jan-June
296,718
113,414
410,132
Percent
of
Change
+ 57%
- 26%
+ 20%
Violations
1973
Jan-June
2,956
2,262
5,218
1974
Jan-June
4,212
1,316
5,528

Percent
of
Change
+42%
-42%
+ 6%
Vehicles in Violation as a
Pej-cent of Vehicles Measured
1973
Jan-June
1.56
1.47
1.52
1974
Jan-June
1.93
1.67
1.86
Percent
of
Change
+24%
+ 14%
+22%
                                       Motorcycles
             Vehicles Measured
                                           Violations
                   Vehicles in Violation as a
                  Percent of Vehicles Measured
Speed 1973 1974
Zones Jan-June Jan-June
Over 35
35 or less
Total
1,217
1,561
2,778
2,533
1,169
3,702
Percent ~~
of 1973 1974
Change Jan-June Jan-June
+108%
- 25%
+ 33%
318
183
501
351
129
480
Percent
of
Change
+ 10%
-3056
- 4%
1973
Jan -June
26.1
11.7
18.0
Percen t
1974 of
Jan-June Chance
20.3
13.9
18.3
-22%
+18.8%
+16%

-------
                                 NOISE TEAM




                            ENFORCEMENT  SUMMARY
                                                                JANUARY 1974
1 HKAVY TRUCKS (vehicle*: with a Gross tfcicht
Year anil
Speed /omj-»


V
)9G9-9moR.
Iil70-12nu>s.
197l-12mos.
1972-l2mos
1973-12mus.
35 and under
Over 35
Total
Vehicles
Measured


159,000
276,280
371 ,074
393,129

29,056
203,040
232,096
Vehicles
in
Violation


1,771
4,047
5,395
4,326

296
1,737
2,033
/chicles
deceiving
Enforcement
\ction

_._
	 .
	
	 .

240
1,196
1,436
J^tjnc of C
Vehicles in
Violation
as a % of
Vehicles
Measured
1.1
1.5
1.5
1.1

1.0
.8
.9
.OQQJPUIICIS and Moro) 	
Cause of Violations
Modified
Exhaust

___
30
52
224

5
68
73
Defective
Exhaust

	
1.046
1 ,617
996

117
491
608
Inadequate
Exhaust

	
	
	
1,771

113
595
708
Other


	
	
	
55

5
6
11

Year and
Speed Zones
1969-9mos.
1970-12mub.
1971-12mos.
1972-12mos.
1973-12mos.
35 and under
Over 35
Total
Vehicles
Measured
2,130
3,623
5,990
6,643
3,254
4,884
8,138
Vehicles
in
Violatior
41
76
615
1.238
327
750
1,077
Vehicles
Receiving
Enforcement
fiction

	
_._
...
272
581
853
Vehicles in
Violation
as a % of
Vehicles
Measured
1.9
2.1
10.3
18.6
10.0
15.3
13.4
Cause of Violations
Modified
Exhaust
	
	
342
790
193
480
673
Defective
Exhaust
	
	
67
112
44
69
113
Inadequate
Exhaust
	
	
...
97
30
32
62
Other
	
	
	
8
5
5
3.  PASSENGER CARS AND LIGHT TRUCKS (G.Y.W. Less than 6,000 Pounds)
Year and
Speed Zones
1969-9mos.
1970-12mos.
1971-12mo<:.
1972-12mob.
1973-12mos.
35 and under
Over 35
Total
Vehicles
Measured
304,434
502.761
677,490
800,250
254,228
402,177
656,405
Vehicles
in
Violation
330
24b
3,925
9,466
3,608
6,335
9,943
Vehicles
Receiving
Enforcement
Action
...
	
	
	
2,830
5,266
8,096
Vehicles in
Violation
as a % of
Vehicles
Measured
0.10
0.05
0.58
1.20
1.41
• 1.57
1.51
Cause of Violations
Modified
Exhaust
...
63
1,983
5,137
1,871
4,246
6,117
Defective
Exhaust
	
47
1,202
1 ,578
843
878
1,721
Inadequate
Exhaust
	
	
	
204
104
102
206
Other
...
	
	
30
12
40
• 52

-------
sium
     By JIM WINSOR







Reprinted from COMMERCIAL CAR JOURNAL

-------
Big trucks 25% quieter than last year's versions can be manufactured in volume. Fast-
changing technology has brought this about at moderate cost increases. But there is a
crisis in the years ahead  if the industry is to meet some of the  state and local laws al-
ready on the books for 1978. Special noise treatment kits could add $500 to a road trac-
tor in 1975 and double that in 1978! A Special Report.
• TKANSCON'S  new  gleaming  Freightliners  pic-
tured here and on ttir cover look and drive like
an\ other Freightliner.  But inside and underneath
there are  advanced engineering  innovations
which make these road units 25 per cent  quieter
than any highwa\ or line-haul tractor plowing the
highways today.
   Rapidly changing technology, coupled  with
changing industry attitudes,  lias produced an as-
sembly-line truck which nearly equals California s
1975 noise limitation of 83 db(.\) . .  . today, . . .
in I973.  That state standard  calls for 83 decibels
on  the  "A  scale.  The  Freightliners have  been
                   •clocked' at 83.5 dh(A).
                     This Transcon-Freightliner endeavor is a major
                   example of what officials ot an image-minded car-
                   rier and manufacturer can accomplish when the\
                   set their minds and skills to it.
                     True, it is only one specific example, using one
                   engine  model,  one  make of cab and  one type
                   chassis.  True,  it is not representative  ot  tin1  in-
                   dustry \s universal  state-of-the-art existing  in
                   trucking today. Still, it is dramatic  proof of what
                   can be done.
                     Figuring,  measuring,  reducing truck  noise  is
                   trick\.  Despite  everything that has been  written
                                                             THE NOISE THERMOMETER
                                             (OUTDOOR NOISEI
Noise  is defined as un-
wanted sound It is meas-
ured in Decibels (db) on
the "A" scale, which most
approximates  human
hearing. The 'thermome-
ter'  shows where truck
noise fits into the overall
spectrum. Note that to-
days heavy-duty tractor-
trailer  will have  to make
less noise than a  food
blender (88  db(A)). That
1978 regulations call for
a truck to be in the same
ranges as a garbage dis-
posal (80 db(A)). By 1988
trucks are meant to be as
quiet as normal  conver-
sation  (70 db(A))1
                                 rtihtary Itl with • fterburrttr. tafcp oH from Krcrlft earner II SO ft 11 30 dBA)
EUMing 707 or DC 8 II 6000 t««t before landing 1106 dBA
PRESENT HEAVY DUTY TRUCK. 35 mph it 50 ft I8B oBA)

HEAVY DUTY TRUCK. 36 mph it 50 ft 11975 R.gulttion) (83 dBA)
                                                                                  (INDOOR NOISEI

                                                                               ThrMhold ot pain luu check m
                                              Riveting machme MlOdBA

                                              Rock 'nroll band (106114 dBA)

•9U




Juil Audible 	




--
^_




' 	 '






60 dBA
SO dBA
40 dBA
30 dBA
20 dBA
10 dBA

-------
              MAJOR SOURCES OF TRUCK NOISE
                      Noise Range db(A) at 50'

             70         75          80         85
The level of noise generated by each source varies with
vehicle speed and with different makes and models of en-
gines. This graph is a composite of today s diesel-pow-
ered trucks. At speeds above 50 mph. tire noise can ex-
ceed all other vehicle noises—depending on tire tread.
road surface,  speed and load. Solving tire noise  without
sacrificing tire life is considered to be the most  serious
long-range problem.
It's important to know that the noise-decibel  relationship
is logarithmic, not arithmetic. This graph makes it easy to
understand.  For  instance,  a 2 db(A) reduction  from 88
db(A) on the decibel scale is actually a 20% reduction in
noise. A six decibel  reduction equals a 50% drop in noise.
A truck measured  at 83  db(A)  is nearly 50%  quieter
than the typical rig on the road today—quite an  accom-
plishment.
      Rtt-AThONSHIPBI
about it, most fleetmen much  less lawmakers \\lin
legislate against truck noise, still don t reali/c that
a trivia] item  on a highly  complicated and  costly
road  tractor can raise the noise output trotn an  ac-
ceptable level to one that is down right obnoxious.
   A pin-holt' leak, lor example, in the exhaust sys-
tem of a big.  powerful,  naturally-aspirated  diesel
engine can mean an  increase oj  three db iA) s. At
speeds above  50 rnph. tire tread design and road
surfaces can mean a  5 ilb(A) increase,  drowning
out engine noise completely in some cases.
   A gutted muffler or straight  pipe \\ill put any
big truck—gas or diesel—over the  S8 or 90 db(A)
limit,  the  most  common  in  existence  today.
('hanging from a single to a dual exhaust  system
can do the same thing.
   Some diesels. by the very nature of their design,
are  noisier  than  others.  Naturally-aspirated  Y-S
diesels are significantly  louder than turbocharged
in-line Sixes. And fan speed,  blade pitch, radiator
shutters—just to name a lew components—all sig-
nificantly  affect  total noise levels.  Important  too.
is that any combination  of these- components will
also generate entirely  different noise levels.
   The proot lies in the prohibition of certain op-
tional items now allowed in California when- new
No less than  12  states and cities have restrictive  noise
laws on their books. Many were passed without regard for
economic consequences or technical feasibility. Chart be-
low shows only the more restrictive noise laws, with Cali-
fornia leading the field.  Congress late last year passed
legislation authorizing the Environmental  Protection
Agency to  set federal noise  limits —something the in-
dustry strongly favors since some state and local laws are
totally unreasonable. Industry sources tell CCJ that a fed-
eral limit of 83 db(A) below 35 mph and 88 db(A) above is
the likely limit for 1974 with more restrictive limits coming
later.
                                                                            Exurior Truck NO.H; Limit!
                                                                litwni*. CoKxxio CtnufD. New Yorh. Propowd •> Nn

                                                                        ^•CcHfwtMi. Colmado. Chio*t°

-------
                                                     TRUCK  NOISE
tmeks  must  l>e ciTtilicil lor u maximum  ol  Sd
dl>(A)
  On  oiu1  Mjtk  truck enir.me .ilinu—till1  \-IS
M.iMilxne.—niiisc1 lalm.ns max xaix Irinii a lox\ <>l
«2 tlli(A) tu .1 limli <»l Sd dl>(A) ilepeuilmj: upon
equipment
    It s .ill  a matter "I  eomponent enmhmalinn
aeemdmji  tu  \l  l-'isliiM. Mack s nuisr .mil emis-
sions expert
    A  truck  designed  l"r diimpei-im\er  seixue
lias dilleieiit f(iiillnt; ii>(|inii niriils tli.ni an mri-
the-rnad luitiii   \nil  i-nuinc Liinip.irliiu-nt  si/c
anil shape  can ailed noise Inn   I isliei sa\s
  One u-alU si-iiinis  pnihlcin  laeinj! tiutkeis is
tliat li-fiallx aii.eptal>le nijs nl luii \i-ais a«o  an-
todax  In-iiif! uli'il  loi noise violations at an alann-
mil  latr in l>m trmk iilu-s like (.hieauo and  the
Inquest tmek slate nl all (..ililnrnia  Heiouls sliox\
that Ixitli (.luiMiio .mil  Calilnima  luxe the loiiuli-
est  muse staiiiLnds anxxxlieie in the  uiinitix   Bui
si^inlieanlK nthei titles and stales  aie e.ili linn;
up  last
  (.lni-.it!!> s nepailinenl "I  I1 nv iionnieiilal C.on-
Inil li-lls (.(.J lli.it 1.500 illations ha\e Iwrn issiii'd
to duikers smie  thai  ut\  s  .inti-nnise lax\  «as
en.ii ted in 1471  \ud tin- KMIX K-linii i.ile is an  1111-
pressixe hi pereent
  The liijinesl nllenders  ( liiiajin sa\s are  I%S-
thniiii:li-lc)7()  iniidel  truiks  \iiil  liueks  10  \i-.irs
or tilder an- licint! iileil 23 peiient nl tile  tune  in-
difatini!  the neeil Ini inoie mid liettei   ntiise
inaiiitenaiiee  prutjiaiiis Meanulnle  Ili-etinen  an-
crxnit!  Innl  x\itli a de.uu-e ol jnsliliLation
    \\lix J   lliex  ask   slinnlil x\i'  spend  lame
sums loi  lelnilitlini: liueks to i lit out tun deiilx-ls
ulien dillerent reiiulatiouv aie on the hooks
or xiill l>e     elsexv lu-u-J
   I Ins tail is tin' most lompellini!  ait^iiineiit  loi
enaitilieiit nl ,i u.ilion-\\ ule noise stand.ud  soinc-
tliniU (.onuiess  lias aiitlion/ed (he  I1 S   1 iixnon-
ini'iital I'loteelion \ueni\ In estaMisli
  hut until it happens  the mil\  sine pioleition
Meet operators IMXI- is to spec  neu  I'liinpnient to
meet standards adopted In  tliose  stall's and loial
iiiinneipalities in uhiih the equipment  opeiates
I'or  lleet-> with nldei  xcliules the tiuik inannl.ii-
Imi'i ent;iiie-inakei  01 .1 noise snppii-ssion spc-
I'l.ilisl  slioulil  In- lonsulted  to Inid  out  the luM
anil  most  eionniniial \\a\ to meet loeal and sl.ile
anti-noisr |.ix\s
    In main i.ises .1 mnlllei  ihan>;i' \\ill solxe  tile
piohlem    ,i  Donalilsoii (.onipanx aioiistie.il  e\-
To reach a given decibel level  engineers must cut the noise output from a number ol components Note thai two 80 db(A|
noise sources combine to make an 86 Conversely cutting 2 db s trom a noise source does not cu! overall noise by the
same amount To reach California s 1973 86 db(A) law truck engineers have cut an average ol 2 dbs from four noise
sources For 75 they II have to cut five more decibels  In addition  they II have to silence at least thiee additional noise
sources m order to leach the  83 db(A) level This equals a 55% reduction in noisei  Two manutacturers toll CCJ this will
cost S500 per heavy-duty road tractor in 751 For 1978-model vehicles with  an 80 db(A) requirement it will take further
noise reductions from the seven areas listed here plus new components—power steering pumps PTO s alternators axles
etc Engine components will have to be brought down  to 68 dbs—an 82%  reduction over todays vehicles Technology
does not yet exist to reach ihese new levels
COMBINING NOISE SOURCES

Combination of Four Predominant Sources Combination ol Seven Predominant Sources
Current Vehicles For 1973. Vehicles
Engine ' «2 T ' "° H Engmi!
UBS-, U83-,
Fan -82-1 ' "° J Fan
- 88 dBIAI 86 dBIAI
Exhaust -82-, -80-1 E»haust
U 85 — 1 1-83-1
Intake - 82 J - 80 J lnuk'

Transmission
Accessories
Tires
For 1975 Vehicles
-75-.
In-.
-75-1
-81 —
-76-,
1-78 -I
-75-1
83 dBIAI
-75 1
- 74 -. ^79 — 1
J
-74 J

-------

Underlying cause for restrictive noise laws are the "rattle
traps" and unmuffled or improperly muffled rigs on the
road today.  Engineers from Jacobs Mfg. Co.  took this
photo of a muffler installed upside down  so the exhaust
passed through  it  backwards. Truck had  been cited  for
excessive  noise  The owner blamed the Jake Brake and
also complained of  no power." Turning the  muffler right-
side up solved the problem. The Jake Brake  has been
charged as a  bad noise maker in some  cases. A truck
properly  muffled under power will  be properly muffled
while the  brake  is on. too. Jacobs engineers say  Oper-
ators with  turbocharged diesels who try to get by with no
muffler (thinking the turbo will  quiet the engine suf-
ficiently) are often the culprit. Most  all of  the heavy-duty
muffler manufacturers have models which will make each
engine comply with  current lavs—with or  without Jake
Brakes.
Lett: California s 1973 86 db(A) noise limit is forcing a number of manufacturers to add noise reduction shields and panels
to engines and  engine compartments.  On the left is a rocker cover noise shield (a rubber noise absorbant bonded to the
cover) on an 1100 series Caterpillar V-8 diesel in a Ford C-senes chassis. Other noise suppressants include molded fiber-
glass acoustical material bonded to thin steel panels and fastened by clips to the engine block. These cut radiated noise
from  the engine by 30%. says Cat. It also increases engine temperatures making cooling—another noise source—more
difficult. Right  Fan  size, speed, blade  pitch, shrouding  and shutters are the biggest challenge engineers face in engine
noise reduction As part of its experimental program. Ford is trying various  blade tip configurations and speeds  in con-
lunction with close-fitting sound-deadening fiberglass shrouds. Closer the shroud, better the air flow and  less  noise. But
when blade tip—shroud clearance is less than '4 in., more rigid  engine mounts or engine-mounted shroud may be re-
quired. Fan speeds under  2000 rpm cut noise dramatically. Manufacturers are also experimenting with lightweight  flexible
blade fans. Some are made of fiberglass, others of stainless steel. As engine speed increases, the blades flatten out reduc-
ing noise  and horsepower  needs. An engine s maximum cooling needs are at peak torque, not peak hp. Other approaches
include the viscous-drive fan and an air clutch actuated fan which engages only when cooling is required.

-------
                                                  TRUCK  NOISE
Lett: Super-size mufflers may be required in the future if exhaust noise is to be cut to the high-30 decibel level. This level
would be required to get an overall vehicle noise level of 70 db(A). Right: These special test mufflers were made by Don-
aldson for CMC. They re over 6 ft tall, have an 8-in. outlet. Price, weight and space requirements will be astronomical.
pi-rt says. "For others, it may mean an air cleaner
or tan problem,  according  to Donaldson's  Doug
Rowley.
  Most truck and engine manufacturers, plus prin-
cipal muffler and air cleaner suppliers, have told
CCJ they favor "reasonable  federal noise stand-
ards. Standards, they say. that are technically fea-
sible, but not economical!) prohibitive.
  But, thev ask. vv hat is a reasonable level?
  Manufacturers are reluctant  to speak for  the
record.  But  from eight  recent  interviews.  CCJ
concludes  the  industry could live with a federal
new vehicle noise limit of 83 db(A) by  1975 or
76. But these same sources warn that  reaching
this level will add considerable cost to big trucks
since special noise treatment packages will be re-
quired for many different engine models.
  One major manufacturer  estimates  it  will add
at least $475 to a diesel-powered straight truck in
the 23.000-to-26.(MX) Ib (AAV range'  Major areas
requiring noise treatment are:
  • A noise suppression  kit for the basic engine
$185.
  • L'nder-hood engine enclosure $175.
  • Modification to  air intake system and certain
accessories $15.
   •  A redesigned exhaust system $50.
   •  Cooling system changes $50.
   For a diesel-powered  tractor, the cost of meet-
ing 83 db(A) can vary considerably, depending on
engine model.  In-line,  turbocharged diesels are
inherently quieter, and,  in most cases, a pre-com-
bustion chamber  type engine  is quieter  than di-
rect  injection.
   Naturally-aspirated V-8s,  both two and four
cycle, are said to present the biggest challenge.
   The estimated  cost of quieting  road diesels
starts at $275.  One manufacturer told CCJ: "We
think we can  reach 83 db's  using a new type
stainless steel fan, doing away  with radiator shut-
ters,  designing better shrouding, adding some bas-
ic under-hood noise  insulation and an improved
muffler. Our  test  engines  come out at 78 db(A)
with this equipment.
   Still another manufacturer told CCJ it  would
cost  $400 to treat their most popular COE models,
slightly less for conventional.  "Right now, were
not sure about two \'-8s. We  may have  to limit
them to certain models and  then only with com-
pulsory options.
   So  it goes.  But the  key  questions go  unan-
swered because thev are  basic-ally political:

-------
  •  Will  the  public  be convinced that 83 db's is
quiet enough? That's considerably quieter than a
food blender and almost as quiet as a garbage dis-
posal in a kitchen sink.
  •  Is the  additional  S275-to-$5(K)  cost  justified
in terms of  benefits, especially when there will be
substantial  increases  for  new exhaust emission
controls atul anti-skid brake systems?
  When taken together, one major original equip-
ment  manufacturer  calculates a  $2000 higher
price tag  to meet all  of the 1975  federal!) regu-
lated safety  and environmental standards!
  The technology to  reach  83 db(A) tor most  ve-
hicles by  1975 exists  now.  But what about the still
lower limits already legislated lor 1988 in Califor-
nia?
  A 70 db(A) level tor big trucks equals normal
conversation.  The technology to reach that goal
simply doesn  t exist today.
  (Jalc Beardsley. h'ord's top truck engineer, says,
"To reach 70 ilb(A), \\e would be forced to design
noise controls for  128 different noise  sources.
Kaeh of these individual sources would have to be
limited to a maximum of-49 db(A).  The- net atlect
would be a heavy-duty diesel  tractor  running at
maximum  power with lull  gross load and wide-
open throttle, generating a  noise level normally
experienced in a public restaurant!
  "It's taken  8000  tests  just  to  certify  our  '7.3
model  trucks. Today, over halt ot  Kortl s total
truck engineering  budget  is  devoted to  noise
abatement  and emission control.
   Mack Trucks  Senior Kxecutive Vice President
tor  Kngineering and  Product,  Walter  May, says:
"We're  confident we- can  be rcadv   tor the 83
db(A) limit without  too  much  trouble.  But  to
reach even 77  db(.A)  will  be a  major  accom-
plishment.  We might  be able to do it in another
live years, but it s too early to say just  vet.
  "At that  noise level, even the gear tooth design
in the transmission  is affected. So will alternators
and power  steering  pumps. It means virtually  a
total redesign ot the  vehicle.
   International-Harvester's chief San Leandro,
Calif, engineer, Jim Cowan, says: "We are partic-
ularly conscious of noise and  emission problems
because of  California s laws. I personally think the
biggest challenge in  the West is cooling.
   "With high horsepower, low emissions and
noise, we've got to quiet the cooling  system at  a
time when  more cooling is required. I think you'll
find most manufacturers looking at ways to elimi-
nate shutters  and slow clown tan speeds it we ever
expect  to  significantly  lower  cooling  system
noises."
   "(jetting both exhaust and air intake noise  lev-
Top: As part of their basic noise research, diesel engine manu-
facturers completely  'cocoon'  an engine in lead-backed foam,
then expose individual components by opening  windows  in
the  shielding and measuring the noise while the engine is run-
ning under load. Here Cummins is identifying the predominant
noises emitted from its V-903. Above: For precise noise meas-
urement under known acoustical conditions  which don't vary.
manufacturers are using a semi-anechoic test cell. This is Cater-
pillar's 18 by 16 by 15-ft cell with walls and ceiling covered with
polyurethane foam sound-absorbing wedges  It's barely pos-
sible to hear a  cocooned engine idling in this room. Right: To
isolate noise generated by a particular system on a vehicle, en-
gineers literally wrap-up a truck so they can measure individual
noise sources on drive-by tests. In this Ford-Cummins proiect.
the  engine is wrapped as well as the entire exhaust system and
air intake.  Systems are extended 20-ft above ground  to keep
these noise sources out ot microphone range. Even the fan is
disconnected.

-------
els down to 68 db(A) will be required before any
truck manufacturer ean produce an 80  db(A)
truck,   according to Donaldson s  Manager of
Acoustical Engineering Systems. Doug Rowley.
   We are asking ourselves  and our engine and
truck OFM  customers some pretty  hairy ques-
tions. Are we ready for  12-in.  diameter  mufflers
with wrapped shells to hold down noise radiation?
Can  we make room tor it on today's trucks? And
can we install an H-in. induction system with a si-
lencing  ring to muttle the pulsations of tomor-
row's bigger engines and air cleaners? Most sys-
tems today arc 8 in.
   Clan  we modify or redesign engines to accept
higher exhaust back pressures? This is an impor-
tant  way to hold  down muffler size and cost tor
the future.'
  Is a 70 db(A) truck feasible?
  Stun Jenkins, noise control director tor  Cum-
rnins Kngine Co.. says this:
   In our testing. \\e have  gotten as low  as  72
db(A) with the engine wrapped  in lead-backed
foam, asbestos sheeting over the manifold, no fan.
a wrapped transmission and rear axle and stuffed
rear wheels.
  " It s eerie to hear a truck like this coast by with
the engine  recording  70  tlb(A). Hut  eliminating
noise  this way  simply isn't  practical.  You can't
service the  vehicle,  much less  operate it ef-
ficiently.
  Noise levels in the mid-70 db(A) range  may
be feasible,  however, with the introduction ot    \
turbine  power.  In  discussions  with  Detroit
Diesel Allison  and Freightliner  engineers.
CCJ  learned that  a  CT-404  turbine  in a
Freightliner  chassis without a  special  anti-
noise package recorded 77 db(A) in a series ol
recent noise  tests. And.  according  to a
Kreightliner  official,  "with a little  effort. I
think this can be improved upon.
  Based  on  all  available evidence,  it  seems
reasonable to conclude that any noise stand-
ard lower than 8-3 db(A). at least for  the fore-
seeable  future1, is unrealistic.  Anything
less than  77 ilb(A) is both technically and
financially impossible with diesel power.
  To find out what is technically feasible
at practical costs, the L'.S. Department of
Transportation s Office ot Noise  Abate-
ment  has funded  four special projects—
three  for over-the-road tractors and one
                                                  TRUCK   NOISE
 for buses.
   The 28-month. $1 million project includes oper-
ating so-called "quiet" trucks in fleet service for
one year in order to develop in-service operating
and maintenance costs for comparison.
   The road tractors are:
   •  Freightliner twin-screw  COK sleeper, pow-
ered by the Cummins NTC-350 turbocharged 350
horsepower diesel   This  unit  is expected to be
ready tor fleet testing by early  spring and tenta-
tively is scheduled  for service with  Mid-American
Lines.
   • An  International CO-4000 cab-over  tractor
without  sleeper, powered  by  a 318-horsepower
8Y-7IN Detroit Diesel. This is primarily to devel-
op data on the two-cycle engine.
   • White Motor  Corporation's Advanced  Prod-
ucts  Divisions short cab-over, powered with the
Cummins Power Torque 270. a turbocbarged.
high torque-rise  diesel and representative  of this
type ot vehicle normally  used with a  live  or six-
speed transmission.
   • Flxible division of  Rohr  Industries  53-pas-
seuger transit  coach with  Detroit Diesel  power
and the usual automatic transmission.
   Donaldson Company is a sub-contractor tor all
project vehicles in  developing air intake and ex-
haust  systems. In  a  companion project,  Stcmco
    Manufacturing Co. is researching the  current
    level ot diesel exhaust noise- on trucks  already
    in use.
      Industry sources say  the quiet  trucks arc
    expected  to  perform  in  the 7."5  db(A)  range
    And information gleaned from  the  DOT
    project will be  shared among all truck  manu-
    facturers.
      Noise tests, unless  otherwise specified, are
    conducted at 35 inph with the pickup  'mike
   50-fcet from  the vehicle. At these speeds, tire
    noise has  not proved  to be a problem  But at
    higher speeds—especially 50 mph or more—
    tire noise  often  surpasses  all  other  vehicle
    noises. The challenge, of course, is to reduce
                  tire noise  without  sacrificing
                  traction and  or wear.
                    L'ntil  reccntlv.  not  much

-------
                         I,
                                                       Significant contributor to noise reduction in Transcon's
                                                       super-quiet tractors is  this Schwitzer viscous  drive fan
                                                       which runs at full speed only when maximum engine cool-
                                                       ing calls for it.
Above: Evaluating the drive-by noise tests results are (left
to right) Lee Sollenbarger, President of Transcon; Bernie
Bolstad, Chief Engineer of Transcon; and Ken Self, Pres-
ident of Freightliner Corp. The new Freightliners (270 of
them) are believed to be the first production run of road
tractors with  noise level readings of  83.5 db(A)—nearly
five decibels lower than the average diesel tractor in use.
Right: Also aiding noise reduction is this Farr Mark II in-
tegrally-mounted air cleaner combined with Freightliner's
Frontal-air induction system.
TRANSCON'S  SUPER-QUIET  TRACTORS
   Transcon  Lines  new  road fleet  of  270 White-
Freightliners are believed to be the quietest  over-
the-road production trucks yet designed. With an
83.5 db(A)  rating during standard  drive-by  tests.
the tractors are some five decibels less than the av-
erage  diesel in  current use—equivalent  to a  25%
reduction in perceptible noise.
   The super-quiet tractors have many engineering
innovations overall. (CCJ will have  a separate ar-
ticle on them next  month.) Noise reduction  was a
high priority item with Transcon President Lee Sol-
lenbarger and was a  design criteria for  the  new
tractors.  The  new  power units were jointly  engi-
neered by  Transcon  and Freightliner and  were
eight months  in the design and  prototype testing
stages.
   Powerplant is the Cummins  NTC-290—a turbo-
charged diesel and one of the quieter engines cur-
rently on the market. To further quiet it,  Transcon
derated it, then tackled the fan  and cooling system
which traditionally make as much noise as the ex-
haust does.
   After extensive testing, Freightliner and Transcon
engineers found that a shutterless radiator and vis-
cous drive fan turning at  engine speed (1:1 ratio
rather  than the 1.2  to  1  which is  more common)
would be satisfactory. The viscous drive fan is sim-
ilar to units used in air conditioned cars. It "slips"-
turning  slowly—until  coolant temperatures reach  a
preset level before  turning at faster speeds. This
not only holds fan noise down but also saves fuel.  It
also gives Transcon  20 more road horsepower!
   During prototype testing, Transcon's Chief  Engi-
neer Bernie Bolstad  said that the fan engaged  full
speed only once in a 2000-mile run—and then only
because the rig was held up  for 15 minutes at  a
road construction site.
   The 83.5 db(A) noise reading was taken with the
fan fully engaged. In actual operation, the  level is
about one-half  db(A) less when the  fan  is  dis-

-------
                                                   TRUCK  NOISE
 was even known about lio\\ tire noise is produced
 let .done how to make .1  (jinel  tin- Rut reecnt
 StlldlCS Iodised  conliil)iites little to lire  noise Tread patterns.
 tre.ul weai and road irregularities ean be ampli-
 fied l>\  carcass  resonance  This  is the natural
 tcndcucv  ot a tire to  ring  like a  hell  when vi-
 hi.iled at  certain lrc(|iiencics \Vlule tins lorm ol
 vihr.ilion IMI  I niled  out as a noise SOIIKC, it adds
 little to the overall problem
   I he  leal (iilput is a phenomenon called  air
pumping—the air so/iec/ing Irom between head
grooves and the road  smhiie  Xciordmg to Robert
engaged
   Other  engineering features contributing to  the
low noise level include
   • An engine-mounted Farr dry-type air cleaner
combined with Freightlmer's Frontal-air intake sys-
tem
   • The new,est type Donaldson "Class A" muffler
vertically mounted but bracketed to the frame rath-
er than  the  cab  This eliminated  noise  transfer
through the cab sheet metal as well as slip-fit ex-
haust connections for tilting the cab The muffler is
of sonic  choke design for  better  sound control It
also has stainless steel "guts" for maximum life
   • Heavy cab undercoatmg and special insulation
around the luggage compartment This helps to re-
duce noise transfer from both the road and  drive-
line to the cab interior
   • A  perforated roof liner inside the cab This is a
1-m  open cell polyurethane foam insulation  which
acts like an acoustical ceiling to absorb noise  as
well as give superior insulation from heat and cold
   • Insulated rubber floor mats  and engine dog
house
   The  total package has not only  dropped exterior
noise the public hears by 25%, it also has dropped
interior noise levels to 85 5  db(A) at the driver's ear
with the window open This is a 5 db(A) reduction
from most road tractors  and 7  db(A) less than
some of the worst
   The  Transcon tractors are within 1'/? db(A) read-
ings of two specially-engineered, specially built
road tractors built by International Harvester just a
year ago in  a joint  program with  the California
Highway Dept
 Miller senior research assoi late toi B K Coodnch
 Tire do.  tire tread (.(impresses radiallv.  traus-
 vcrselv  and longitiidmallv  lorcmi: uir out ol the
 tread voids as  the\  come  into (onlact with the
 road  When  (he  tread  tolls  out  ol  contact, the
 compulsion is relieved and .111 llo\\s hack  into the
 expanding voids
   The amount  ol  noise gcueiatcd hv this action
 depends on such lac tors as tread  depth  uroove 01
 void uicllli circumlerential  tread spacing  the
 number ol grooves across  the width ol  the hie
 .UK! vehicle speed
   Tread dcsiun and vehicle speed does elleet the
 level ol noise produced A smooth tread is <|iuet-
 esl ol all  It  presents the  smoothest  piotile  as it
 moves through  the air and its non-pattern head
 unmmi/es carcass vibration  With  no voids  to
 worn about  verv little air pumping,  it anv  takes
 place
   The  straight  lib  tire !•• almost  as (|inet  as a
 'slick   On a smooth load  it can give use to some
air pumping  But on a slightlv  lough surface  it
can actnalK run quieter than I lie slick
   I ires  with sawtooth ribs enntiibnte more to air
 hiiluilencc carcass vibration  and especiallv air
 pumping  but still  are not  the noisiest The loud-
 est cnlput  ol all is the cross-hit;  lire which pro-
duces the greatest air pumping  Unlorhinalelv  as
the trucking  mdnslrv  well  knows, cross-lug  tires
give  the best hactiou  and longest mileage—an
unbeatable combination
   Speed also plavs an important lole in tire noise
 I-or each  10  mpli increase bel\\een 10  and 70
inph  there is a corresponding llnee-to-si\  decibel
increase m tire  noise levels I'inallv  other agents
contribute m some degiee to the problem  such as
tvpe  ol  road surface  load,  inflation pressures and
tread wear
   Increases m tire noise levels due to  load and
pressure changes are most noticeable with cross-
lug tires  Increasing  the load on a tire adds  to
tread tlcuiig and  also  increases  noise  levels
caused hv air pumping  Decreasing inflation prcs-
sme has the same elleet
   As a  general  rule  ol  thumb, the level  ol tire
noise  increases  as  the  tread wears Irom  new  to
hall-worn  At tins  point, it  decreases again until
the tread becomes smooth
   ^ct to In: measured  is the elleet  ol irregular
wear, although it is believed to he a contributing
 laetor At the same time small changes m tire si/e
have little  impact on noise levels—there s a one
decihle  diflureiiLC  between an S 25  \ 20 and a
 10 00 \  20 tire ot the same tread pattern on the
same vehicle,  lor example
  Tube-t\pe and tuneless tires both generate sun-

-------
 Right: Varying tread pitch breaks up objectionable  tire
 droning. Paper tape shows shorter  tread  segments to-
 wards bottom. Practice is most effective on car tires.
     100
  *   80
      bO
                               POCKET TREAD
                               HALF WORN RIB
                 .'
                30       40       50        60


                         VEHICLE SPEED - mph
Above:  Graph shows typical  noise  increase  for various
types of truck tires between 30 and 70 mph.
   EDITOR'S NOTE
     The following manufacturers, associations, gov-
   ernment agencies and fleets furnished data and/or
   were interviewed in preparation of this article.  The
   editors wish to thank  all of them for  their coopera-
   tion.
   Caterpillar Tractor Co
   Cummins Engine Co.
   Detroit Diesel Allison D
   Ford Truck Div.
   Freightlmer Corp.
   International Harvester
   Mack Trucks. Inc.
   While Motor Corp.
   Donaldson Co.. Inc
   Farr Co
   Riker Mfq  Co
   Stemco Mfg Co
   Flex-a-lite Corp
   Morton Industries
   Schwitzer Corp
   Jacobs Mfg. Co.
           Pacific Intermountain Express
                 Western Gillette. Inc.
                     Transcon Lines
                   The Ryder System
            Firestone Tire & Rubber Co
                B. F. Goodrich Tire Co
            Goodyear Tire & Rubber Co.
                 Rubber Mfgrs Assn.
Engineering Dept.. American Trucking Assns.
             Western Highway Institute
  Engineermq Section. Calif. Highway Patrol
    Chicago Dept of Environmental Control
        Environmental Protection Agency
      Bureau of Motor Carrier Safety. DOT
         Office of Noise Abatement. DOT
ilar levels of noise for similar tread patterns  Radi-
al tires  have been knouii to produce slightly low-
er  noise levels  than  bias-ply  types.  Surprising.
doubling the aetuul number of  tires on a \ehicle
increases the sound level by  only about 2 db(.\).
   Clearly, tire  noise i.v  a problem today.  And  it is
likely to  get worse as  noise  restrictions  become
more stringent.
   Lug-types  commonly  used on drive axles  are
the biggest  offenders,  producing anywhere  from
SO to nearly  100 db(.U Yet, they  are the very tires
that  give the best traction and wear.
   A  1971  Rubber  Manufacturers Association  re-
port  to  DOT's Office of Noise Abatement,  states
that  lug tires give significantly better lateral trac-
tion  and  driving torque  than their  rib-type
counterparts. And up to 100 percent better trac-

-------
                                                  TRUCK   NOISE
II your new lug tread tires (left) are wearing to form pock-
ets (center),  or if you're running retreads like this type
(right), then your trucks are probably among the noisiest
on the highway
                13979
                TIME AFTER PASS-BY (SECONDS)
Noise from pocket tread lire persists, and even grows
louder, long after vehicle has passed by Phenomenon is
due to directionality of noise emitted by tires
tinn  on siiou and icr  Heiause the luii tires rmul
Irc.ul elements cnii he molded some d()  percent
d(T[XT. mileage is increased l>v l?0 peiienl over
DtlltT i\ |)CS
  Sniff llii.1 RMA report slates      lliere .in- no
known techniques lor reducing soiiiid levels <>\ lug
tire.s to those ol rib tires Milhoiil senonslv  impair-
ing trdL-tion and tread  wear,  the nvcriidiiig i|ncs-
tion  still remains unanswered as to whether or tint
llii- induslr\ will he lori-ed 25 vears backward to
satislv luliire lire noise limits
  Cab noise  is still another  major concern he-
cause ol its potential ellect on driver fatigue, sale-
l\ and heal ill  An\ tiling manutaclurcis do to re-
duce  exterior muse alleets interior  cal> noise as
uell  \\'rapped innfllers. bracket-mounted  nil the
liamc  (instead  ol attached to the  cab),  lor e\-
ample rediHe noise transfer drashcallv—as  much
.is fi decibels in extreme uses
   \lso. the simple ait ol plugging np holes in the
lire uall or cab lloor can result in a significant re-
dnetion in mtenoi noise
   l?nth  DOT s Uiirean ol  Motoi (.arner Salet\
and the I' S Labor Department, charged uith eu-
lorcinn  the  \\alsh-lleaK  Vet  and Occupational
Salelv  and Health  Vet.  ate keenlv  interested in
dmer welfare
   llarr\  (.'lose elncl  ol (he n-seareh  division ol
the olhee v
DOT and  the \inerican   liuckmt;  \sMiti.ilions
and repoiled in (,CJ in Deeemhei 1971 l)0 dh( \)
\\as lomul to he  the median in-c'ali noise. 95 I he
maximum \\illi \\iudin\s open  and 
-------
A  New  Concern  for  the Trucking  Industry
Engine  Intake  System   Noise  Control
 By  B.  M.  SULLIVAN1
   THE noise level of your vehicle was measured
   at 89 db. You've broken the law and I'm afraid
I'll have to give you a citation." These words will
he repeated to  truck drivers over and over  again
in the coming years as the various states continue
to legislate greater degrees of "quiet" into our so-
ciety. Trucks are a prime target for legislation he-
cause they are one of the more ohvious sources of
annoyance, and pending  noise laws have met little
or no opposition.  In January, 1973, 86 db(A) will
he the maximum noise level for trucks in Califor-
nia, Colorado,  Nevada,  the city of Chicago and
several  other states and municipalities. In Califor-
nia  these levels will be  reduced progressively to
83 db(A) in  1975, and 80 db(A) in  1978. These
steps do  not seem like  impressive reductions—
until one understands that a reduction of 8  db,
from the existing level of 88 db(A) to 80 db(A) in
1978.  represents a decrease in  total  truck trans-
mitted noise energy of 80%. Removing this sound
energy  will  require increased engineering effort
and  improved components. Ultimately,  it will be
the consumer who picks up the increased cost of
providing quieter trucks.

Lowering noise can be compared  to trimming a
hedge. The longer branches must be cut to trim
the hedge. Cutting the shorter branches will not
affect the height of the  hedge very much. Simi-
larly, combating truck noise means defining those
sources which  are the loudest and  working  on
them first. For example,  if total truck noise  is 86
db(A), quieting one noise source  from  75  to 70
db(A) will have no measurable effect  on the total
level. However, if  an 83 db(A) noise source can
be found and lowered  to  78  db(A), total truck
noise will be  reduced by  2 db(A) or to 84 db(A).

'Product Engineering, Donaldson
Co., Inc., Minneapolis, Minn.
This Kenworth tractor, fitted  with a Cummins  NTC-350 turbocharged engine,  registered 82 dbA  in tests on
Donaldson's test track.  Proper selection  of intake and exhaust equipment contributed to the noise reduc-
tion. Also fitted is a Morton fan clutch which disconnects  the fan when airflow through  the radiator is other-
wise sufficient to meet cooling requirements.
Setup for intake  noise tests performed to predict
the performance of air intake system when installed
in a tractor. The engine is located behind  the well.
The setup measures "insertion loss" by permitting
measurement of  noise levels  of  the open  intake
pipe and then with the air cleaner installed. On the
control panel is an XY recorder which plots decibel
output against engine rpm, and a Spectral Dynamics
tracking filter and analyzer. Tests are  also run  on
trucks with  this system  prior to running  them  on
the test track.
As has  been  documented by test,  there are five
major noise sources  on a truck.  They include:
Fan Noise—This is noise generated  by the cooling
fan. This noise problem will become increasingly
severe as larger engines, which  require  increased
cooling,  appear on trucks.
Intake and Exhaust Noise—These are noises gen-
erated by the engine and carried in the intake and
exhaust  systems.  The  noise is transmitted to the
atmosphere  from the  walls of the piping as well
as from  the pipe  end.
Engine Mechanical Noise—All  internally gener-
ated  engine  noise, except  intake  and  exhaust
noises, falls in this group. Included are valve noise.
gear noise, combustion noise and others  that are
transmitted through the walls of the engine.
Other Mechanical Noises—This group  includes
all  mechanical noise  sources  except the engine.
Items such  as transmission noise, chassis noise,
and others fall in this group.
Tire Noise—Tire noise is difficult to reduce.  It is
the predominant noise source at freeway speeds,
hut below 35 mph, where most legislation is writ-
ten, it is not a predominant noise source.

Several years ago, as demands for better  mufflers
to reduce truck noise were received, Donaldson
Company originated its work in  the area of truck
      Reprinted  from January 1973  North American Edition of DIESEL & GAS TURBINE PROGRESS

-------
                                           Mechanical Noises
80— Engine Noise"

80	'Fan Noise
>
   Figure 1. Two noise sources of equal magnitude will
   produce a  noise  3 db  louder  than  either  noise
   source alone. Based on the above chart, this prin-
                               FNGINE TYPE

OPEN
FWA.
FHG,
EBA
INTAKE
-• 0
EBB { 	 ^
- «Q
~ tT)
IlHHOCHARCfD

61-72
62-72
61-71
6-7,
NATURALLY

67-76
67-76
65-75
67-76
MECHANICALLY

63-73
63-73
62-72
66-76
 Figure  2.  Intake noise  levels as  measured with
 newer-design air cleaners on some engine types.
Figure 3. The  chart shows  how noise reduction is
affected by  ratio  of air cleaner  body diameter to
duct tube diameter; as ratio increases, sound atten-
uation goes  up.
noise source isolation.  The  reason  was the ina-
bility to reduce overall truck noise  in some cases.
despite the application of improved  mufflers. One
of the serious  problems  discovered was that  of
engine intake noise;  levels  as  high as 95  db(A)
have been measured during extensive engine test-
ing. If the goal is an  86 db(A)  truck, these  intake
noise levels must obviously  be reduced. In fact,
to provide  an 86 db(A) truck,  intake noise may
have to be suppressed to a maximum of 76 db(A).
This is shown in Figure 1.

Intake noise is a result of several  factors.  On  a
naturally-aspirated engine, it results from  pulsa-
tions caused by the opening and closing  of the
intake  valves.  On  a  mechanically-supercharged
engine,  it includes the  noise  generated  by  the
supercharger. On a turbocharged  engine,  it in-
cludes noise generated by the turbocharger. Intake
noise generally increases as engine speed increases.
                                                                                 86  Total  Truck
                                                                                         Noise
                ciple shows how a maximum 76 db(A) intake noise
                may be required for an 86 db(A)  truck. Many other
                combinations are possible, however.
                                                     Inside Pipe Diameter        Airflow Range (cfm)
                                                            4"                        100-400
                                                            4VS"                      225-500
                                                            S"                        350-600
                                                            5V4"                      400-750
                                                            6"                        450-900
                                                            7"                        750-1300
                                                            8"                       1000-1700
                                                     Figure 4.  Recommended pipe size for common en-
                                                     gine intake airflows.
                An excellent way of reducing intake noise levels
                is through turbocharging. Engines which are turbo-
                charged can provide noise levels 3 to 5 db(A) low-
                er than the same engine without  a turbocharger.
                Side benefits of  turbocharging include  lower ex-
                haust noise and engine noise  levels, lower smoke
                levels,  and  lower exhaust emission levels. Peter
                Shutz,  of Cummins Engine  Co.,  has said, "The
                biggest  single  technological  accomplishment  in
                the truck  diesel over the last  five years  has been
                the perfection  of the  turbocharged engine." The
                benefits piove his statement.

                Additional  noise  attenuation  can  be   provided
                through the use of intake silencers. Such  silencers.
                installed in the intake system  can provide an  ad-
                ditional 3  to  4 decibels attenuation, an amount
                which may be significant when lower intake noise
                is required for a "legal truck."

                The  key,  however, to good  intake system noise
                control is  the air cleaner. A properly designed air
               cleaner can mean the  difference  between provid-
                ing a "legal truck" and an  illegal one. Proper air
               cleaner system design lies  in properly  matching
               the duct sizes to the cleaner size, proper inlet  de-
               sign  and location,  and proper  design and location
               of interior components such as the filter elements,
               baffles, and finned or vaned centrifugal separators.

               The  difference  between intake  noise with a well-
               designed unit and  one  which is not can  be 15 db
               or more.  Keeping in mind  1973  requirements
               which may  dictate a  maximum  intake  level  of
               76 db(A), Figure  2 shows the sound  levels  of
               newer truck air cleaners on some of today's en-
               gines. These cleaners may  have to be  upgraded
               or replaced to  meet future requirements.

               Increasingly high  engine airflows also present dif-
              .ficult problems  to  the  induction system  designer.
               Familiar truck  diesel engines such  as the  NHC-
               250, NTC-290, and 6-71 which require 400 to 700
               cfm will be replaced  by engines requiring  1200
               cfm to  as  much as 1700 cfm. The problems  of
 providing filtration and better noise control at in-
 creasing  airflows,  dictate larger systems.  Eight-
 inch diameter  ducting as  well  as  air cleaners
 twice the volume of today's units will  have to be
 considered. The need to mount an increasing num-
 ber of  accessories while trying to minimize over-
 all truck size and weight, will place great demands
 on all  component  engineers  including the intake
 system  designer.


 Proper matching of duct size to cleaner diameter
 must take  several factors  into  consideration in-
 cluding pressure drop, cost, installation space, and
 sound attenuation. Figure 3  shows the  effect on
 sound attenuation created by increased duct size.
 As the body diameter to tube diameter ratio in-
 creases (i.e smaller diameter ducting), the sound
 attenuation goes up.  However,  the  reduction of
 pipe  diameter results  in increased pressure drop
 in  the  intake airflow.  Figure 4  shows recom-
 mended pipe sizes for the common range  of intake
 airflows found on today's trucks. Use  of smaller
 pipes than  those recommended  can  result in an
 additional 3" to 5"  of water pressure drop,  re-
 ducing  net horsepower  and increasing  fuel con-
 sumption,  penalties which the truck industry can-
 not economically accept. The answer to the prob-
 lem,  then, lies in properly matching duct size to
 engine  airflow,  and designing the  air  cleaner to
 provide most of the attenuation.

 Proper  inlet  design and location  are very import-
 ant in providing needed sound attenuation. In gen-
 eral,  open inlet  air cleaners should be  avoided
 unless acoustically treated in  some manner. Tubu-
 lar inlet cleaners provide the best sound attenu-
 ation and.  in many cases, the inlet can  be located
 in a "cleaner" area, thus extending filter life. In-
 lets should not point directly at a spectator. Direc-
 tion of  sound can  be as important as  loudness.
 As  an example,  trucks  with  loud fans  may be
 noisier as  the truck approaches than as it goes
 away from the spectator. Why not locate  the inlet
 such that  the sound radiates  backward and does
 not add to  the  fan  noise? This  could  mean the
 difference  between a  legal  or  illegal  truck. By
 1975, additional demands for increased filter life
 and lower restriction will also dictate new designs.
 Higher engine airflows  combined with  less space
 will further complicate the picture.

 Another noise problem receiving serious attention
 is that of driver exposure to excessive noise. The
 Occupational  Safety  and Health Administration
 has  placed  the  maximum exposure  level  for  a
 worker  at 90 db(A) during  an eight-hour day.
 In-cab noise  levels of today's trucks often exceed
 that level.  As in the case of exterior  noise, the
 problems  must be attacked  through noise source
 identification.  It cannot be assumed that  quieting
 sources which affect exterior noise will also reduce
 in-cab noise.  The sources might be  completely
 different. The fan is frequently the prime source
 of in-cab noise on COE tractors, while the exhaust
 system shell noise is a prime offender on  conven-
 tional trucks. Not without fault, however, is intake
 noise which  under  certain  circumstances can
seriously affect in-cab noise levels. Some examples
of these circumstances might be: underhood inletsr
intake piping inside  the cab,  and air  intake  im-
mediately  outside a window.

-------
donaldson
                                                           product  engineering
   ACOUSTIC TECHNICAL BULLETIN
   Subject:  SOURCES OF TRUCK NOISE
Issue Date:
Sheet:
Project:
ATB No.
12- 21'- 70
1 of 4
891 8C
20
With many States now demanding strict control of truck noise,  the truck manufacturer,  in order to
most economically comply, must have a thorough understanding of the major causes of vehicle
noise.  Manufacturers are already experiencing difficulties in  meeting the present level (88 db"A")
with certain chassis-engine combinations.  Yet it will become increasingly more difficult to  comply
with future levels (i.e.,  California 86 db"A" in 1973), and will be a most formidable task if
requirements should be made even more stringent.

This Bulletin was prepared in an effort  to assist the design engineer in understanding and then coping
with the various noise sources of over-highway trucks.

The magnitude of the truck noise problem is
usually underestimated.  The general public,
legislators, and even their technical consul-
tants and enforcement officials, may still
refer to truck noise as "exhaust noise," and
hence, in their eyes the solution to the prob-
lem is simply a better  muffler.  While it is
true that  with an inadequate muffler,  exhaust
noise is the major culprit; this  may not be true
when overall truck noise  levels reach 88 db"A"
or less.  At these levels other sources than
exhaust are significant contributors, and
    be even more significant at 86 db"A".
   wi
   Under these conditions and because of the
   nature of sound, oftentimes it doesn't help
   much to treat one source without also
   treating one or more of the others.
   In order to control truck noise, one must
   first identify what must be controlled.  The
   engineer must determine the characteristics
   of the individual  sources, and must also determine the relative magnitude and importance of each
   as a contributor to the whole.  Then, the degree and method of noise control can be considered.

   The total noise radiated by  a vehicle is made up of four principal  components - each component
   consists of a source and a sound transmission path.  The components are exhaust, mechanical, fan
   and intake.  (For simplicity, the noise  created by combustion, gear and valve,  pump, transmission,
   etc.,  have been lumped into one source as mechanical noise.  Tire noise was not included because
   it is generally not significant at less than 35 mph).  The properties of these components for four
   different trucks are presented in the Table.  The trucks are not necessarily current production. The
   data shown was gathered by measuring each individual component  while operating the  truck per
   SAE J366.  The truck was maintained in the original production condition for that particular com-
   ponent being evaluated while essentially completely silencing the other three.

-------
ACOUSTIC TECHNICAL BULLETIN                          Issue Date:     12-22-70
                                                          Sheet:
                                                          Project:
Subject:  SOURCES OF TRUCK NOISE                     ATB No.    	20.
The individual noise levels shown can vary with the properties of the source, with the overall
noise objectives of the engineer, and of course, with the noise control means at his command.
The latter is twofold -  the actual source and then the sound transmission path to the measuring
microphone.  The source is defined as that which creates the original noise, and the path as being
between the source  and the microphone.  As an example,  the exhaust noise is created by the
engine, the source, while the path is the exhaust system and the distance between the system and
the microphone position.   Both source and path are roughly of equal importance in controlling noise

       NOISE LEVELS OF SOME TYPICAL OVER-HIGHWAY TRUCKS, 50 FT. DB"A"

                          Exhaust     Mech.     Fan       Intake        Total
            Truck           Noise     Noise     Noise     Noise    Truck Noise
                            86         83         81         80          89
                            82         85         83        80          89
                            83         83         78.5      72          87
                            77         81         82        70          85.5

Since the  levels in the Table include the effect of the sound path, the values could vary
widely depending on truck type (COE or Conventional) and manufacturer.  These are discussed
individually below:

      Exhaust:          Depends on exhaust noise properties of engine. Will vary with
                       muffler; tail pipe length and location; flex pipe; and exhaust
                       pipe length, construction and thickness.  The exhaust noise
                       includes both gas-borne noise as well as exhaust "pipe" and
                       muffler  "shell" noise-

      Mechanical:      Depends primarily on mechanical noise properties of engine,  but
                       also includes driveline noise.  Will vary with engine compartment
                       (hood,  side, and under panels) and cab (back or tunnel panel) sheet
                       metal - how treated, how well enclosed, how well damped, and
                       reduction in "line of sight" sound transmission.

      Fan:             Varies  with power input and fan design,  efficiency, tip speed, radiator
                       and shutter type, shrouding, and proximity of nearby obstacles.

      Intake:           Depends on intake noise properties of engine.  Will vary with air
                       cleaner style,  air cleaner location in induction system, system piping
                       size, air inlet location, and with added silencer if used.

The information in the Table may be used to select areas for control and then to predict the
effect on the total level.  As an example, suppose it is desired to reduce the noise of Truck
One to 86 db"A"  from the 89.  Obviously the most benefit would be derived by installing a
better  muffler,  but even if exhaust noise  were completely removed, the mechanical, 83,

-------
ACOUSTIC TECHNICAL BULLETIN
Subject:  SOURCES OF TRUCK NOISE
Issue Date:
Sheet:
Project:
ATB No.
12-22-70
3 of 4
891 8C
20
the fan, 81, and the intake, 80, would combine to yield a level of 86.5 db"A".  Hence,  to reach
the goal, let's arbitrarily say the exhaust contribution should be no more than 81 - which would
allow for a reasonable size muffler but may require a double wrapped body and  a heavy walled or
laminated exhaust pipe.  Then reduce the intake to 79 and the mechanical and fan noise to 80.
The latter two will respond to under-cab acoustical packing and engine enclosure paneling (enclosing
engine may in turn require revising engine cooling package).  The combination of the resulting
mechanical and fan, both 80, with the 79 of the intake,  would then be 84.5,  and along with the
exhaust of 81 would just meet the  desired 86 db"A".

With Truck Two the overall  noise level could be reduced most by decreasing mechanical noise
rather than exhaust.  From the Table many other situations can be described which will indicate
the difficulty of reducing truck noise.  Since the data used is  for average trucks, many trucks
and their individual components may be less or greater than shown.   For example, some existing
trucks cannot meet the 88 db"A" level even with the exhaust noise completely silenced.  The
individual sound levels shown could change as  much as 10 db"A" depending on  truck design per
the above variables.

In order to assist in  the noise control technique, octave band levels should be taken for each
component.  Further to aid the engineer  in designing required attenuation into the noise paths, it
is expected that in the future source noise data will be made  available by the manufacturers of the
engines,  transmissions,  fans, tires, etc.
                      m
                      a
                          90
                          80
                      Cu   70
                      LJ
                      cn
                      o
                                      mechanical

truck

p^n =
_». .
start
point
T-»
l\

• acceleration
end
point
lane

                                             mike

                            EFFECT OF NOISE  SOURCE LOCATION AND
                            RADIATION PATTERN ON MAX. TRUCK NOISE

-------
ACOUSTIC TECHNICAL BULLETIN                            Issue Date:    12-22-70
                                                            Sheet:        4     of
                                                            Project:         8918C
Subject:  SOURCES OF TRUCK NOISE                        ATB No.          20
For the analysis, the levels of each component were shown at the instant of maximum total read-
ing of the Sound Level Meter. That is, some of the contributors could be actually louder than
shown but occur at a slightly different point of the  "pass-by. "  For instance, the fan noise with
shutters open has two peaks - one as truck approaches mike (noise through radiator) and another
after truck has passed mike line (noise emanating through cab rear tunnel). This is estimated in
the curve.

The separation of component effect can be cultivated to advantage since the truck  is not penalized
for duration of noise, but only for peak reading.   Hence,  by spreading out noise,  total acoustic
power output is the  same, but meter peak reading would be less. One means of taking advantage
of this would be to position intake snorkel on cab rear left side with muffler on right side in an
effort to decrease the intake's contribution to peak noise.

SUMMARY
Because of the many factors and combinations involved, decreasing truck noise is not just "getting
a better exhaust system-"  It is a complicated and expensive engineering problem with potentially
costly solutions.  The total truck must be considered, and the more one understands and knows
about the noise sources and paths, the more economically he will be able to meet the required
noise limits.

The problem will expand if/as noise limits are tightened while at the same time engines are
getting bigger and more powerful, with the inherent increase in  noise output.
 DONALDSON COMPANY INC.                                 Product Engineering Department
 MINNEAPOLIS,  MINNESOTA                                   Acoustic Systems Engineering
                                                                DWR/js

-------
  Reprinted with  Permission,  Copyright   ©  Society  of
  Automotive  Engineers  Incorporated,  1972,  All  Rights
  Reserved.  Paper  720924  from  SAE  SP  373.
                                                                                                      720S2'
ABSTRACT
  A LGi'crptual fr..niework has been developed for in\e«t!jat-
ir.g ti..- bJfifrj'iior. uf sound by lircs. Recent measurements
l>2\c quantified seme of ll.c chsrattenslKi of Iruck lire
sou--!»  The chaucierijtics tliai have bc.-n measured includi
ilii f.:k 4-\veighi:d io.ud level and it* dependence on the
trc.iu '.'stiern, sp:.'d. ./id deflection of ilic tire, ihc cflccl of
Ihe iojd surface on ere io»nd levels; anJ Iho spectral dislnbu-
tio:: of '.ire soundi. llnse characters:.:* are discussed in
lernis of the rnechznis.ns of tire sound generation.
      Eli *>
                        , ,:• .**   ~ r"'- : •'• ' *"? O  f v ,
                     Vt   .•.> %» K il Wl « k B V.» . t t **»  *•-•' 8

                           P   ^**^              r B
                   B •-•«'•. I   (• r: *>•.-.. r:"*?  .?"•?"'
                   di. ?. ._<   ^IVi^i. k*«rC Ui U.L >_ 1 I.
                                                                              T.  R.  Wik  and  R.  F.  Miller
                                                                        Research Center, B. F. Goodrich T«rc Co.
Ti-!L PURPOSE of this paper is to invest -j-ate how the inler.'i-
l-.oii (..f.tr.c surfaces wiili the surroundii'g air produce^ sound.
Tli.* ri.ecrwifm? b> nuans of which a ro'lmg tire can displs.e
sir ?rc considered or.e ui a time. The measured ch.iraci:risucs
of lir: sounds are then di->:ussed in loinis of ihe c\p:clc J Cii.i-
Inb'.iMOn of each injcran^ni.
   O. ';. ..-il-oii'L- MJ-JI: Ji ;;Li cuteii .-I li1-.- I:!'.1 surfaces jnii .11
tl.i ." icrfj.'C b2tv.ce'i lire and road surfaces arc considered.
The >>-.jr!(Jsgener.:'':(l b> \ibrationscflhe \chicle or of ihe
rGad'.oy'as a result  of nbrsuons transrcrrcJ b> the tiros .ire
rot co:n!ui.-red. The su'inds generated b\ \c!ncubi and roaj-
\va\ vibrations 3ic a function of the co-iiiruction of tKj vehi-
cle .in i i he roadway .:s v.cli as of (he tires.

MECHANISMS OF TIRE  SOUND GENERATION

  As a lire rolls over a road surface, it dirphces macroscopic
and n:i;rcs:op!c \o!un  i.ieans of v.hich the rolliM^ lire can displace
air.
   1  Tr.Visblicn of the \vliule tire thiough the air
   2. Acrudvnjmic effects.
   ?  Carc^sN and lre:iJ xibrations.
   4  MLLiuniCtf! p.'ir^-iu^ of an 1:1 ihc re»ion where the lire
       is the icad suiLice.
 TR \\SL\TION.\1. MOTION1  OF  Till: HUE
 TllKCXGl! 1Mb AIR

  Tiji.sldtio-i of the IMC ibrcuch the .11- .'.lip'.'ccs large \i'l-
 u:ii-:s of air ?.l rcljti\cl> h"t.h lieu r-'.i-s  ! !i? pi assure i!i-.i:!i
bance as>ocistrd with this, r^crcscopic fli).v ofnir is not. h-,w-
evci, v.'hat is poic?ived ::; ti.v sound  ') Ins pressure distu.-bjiue
varies too slov ly, both .is .1 funcuoM of tmi.- .'.ni! as a funclio".
of sp3ti..! cciordmaies, ".i proJiice audiWe ioyid.  Fui (>.<.:•
muic, tlii? piessuie UistPrb^iuV is nonrccurrm,'. for an «.ibs?r\er
aloup the ro:iJ\'.ay. Tlics? conclusions jie ba\:d on l!w ai.jl-
Q£J bcUMiei1 ihe nonturbui.n1 cumpf":!!1. •.>.';!.; fiov.  isf.-ir
around the tin- and Ihc I"! 'v. Of air art-urd a y U:-MIC .i.rl 'il
Fig 1 giici a plot of II c pross'.rc varutions p.jJv'.ccd b\ ? .vjb-
some I'lrfoil as a function c/ Jistancc r>'o;ig a s'.r-iuht iiue
parall-1 to the direction of r*.o'.:on (1 ) "
  Fig 1 A »hows ihc velocities .pducetl in ,,u. ir-:i.i!l> .il rest,
by Ihe p.-«s.:«:e of a two u!-n:i.>;o:ial. sv pMieiiii: airfoil. The
vcctois Indicate the nia>!nm..!c .T.I! iln^c'ion cf iJw air \e!oc-
itics.it c^ch point.  Fig. IB S!"-OAS the  puNMi.-e rJi^iribiitiuii
along the lm« paiallcl to thi direction cf ii.otiun of the ?'.r-
foil. A plot of the prc-.su:.' -.ariancn as j function of Inve for
a slaiioiiar) observer \M!! b.¥ identic.il  lo ll'o plot of the pros-
sure as :i function of diiUn<.c. The time intei\:l icpl.icinj a
given distance interval d:p?nds on t.ie velo-jii) of ihe airfoil.
                         t = d/v
where:

   t  = tune
  d  = distance
  v  = velocity of lire
                 EFFECTS
                                                              All sources oi strbornc sound d<.p?:ul on il'O dynamic piop
                                                             rtlCS of ll'C :'lr. I" till* V.^:INJ, .'II «Oi:n.cS di MViild .'1C 2t ••••
  -'Nurr.b.-ii r.1
paper
                         r'esisnsic Rcfcrr noes at end of

-------
                AIRFffl	v
                                      B
Fig. I - Velocity and pre
formations lint occur once per lire  revolution when a particu-
lar  portion rf ihi- tire enters or leaves contact v\it!i the road
surface. The deformations of tread voids in HIV. near the con-
tact patch, for example, arc not considered to be  tioad vibra-
tions.  Three  causes of carcass and trend vibrations that  may
produce ;m Jible sound are:

  I. Tread pattern  can produce load modulations that excite
vibratory  deformations in tits carcass and treaJ. Th; atiTi-ii-
tudes of ilie carcass and ue.id vibrations introiiukeJ by  the

-------
tread pattern depend on the size and configuration of its ele-
ments
  1.  Road asperities can introduce carcass and tread vibrations
in a manner exactly analogous to the vibrations produced by
the tread pattern. Asperities in the ro.td surface can produce
vibratory deformations due to load modulations.  The ampli-
tudes of ths vibrations introduced by the road surface depend
on the size and the placement of the asperities in the road sur-
face.
  3.  Tire nonunifonr.ities can also excile carcass and tread vi-
brations. The amplitudes of the vibrations introduced by non-
uniformities depend on the severity of the nonuniformlies.

  Carcass resonances modify the pattern of surface deforma-
tions by emphasizing those  frequencies (hat correspond to
natural modes of vibration in the carcass.  These resonances
modify the deformations resulting from all three inputs-tread
pattern, road asperities, and nonuniformittes.
  Accurate measurement or calculation of the vibrational de-
formations of (h: carcass and tread is very difficult. Further-
more, zn exact calculation of the sound pressure levels gener-
ated by the deformations is difficult.  Consequently, this
method has not ban used to determine the contribution of
carcass and tread vibrations to the overall  sound level ex-
hibited by the tire
  Ha\ e'en  f2) es!in:?.:ed this contribution, using an en-.pincal
technique. He measured the sound power-level spectra for
various input acceleration; applied normal to the trend   These
measurements perni'l  the prediction of sound levels bai.'d cui
vertical accelerations rrcasured at the tread. Since it is not
possible io measure the vertical acceptations at the tread, Hay-
den calculated the input accelerations at the tread from (he ac-
celerations measured ai the axle  Ths sound levels predated
for ca.'cass vibrations \vere not significant  relative  to th;  total
sound level exhibited by a typical  patterned tire  Havden con-
cluded that the accelerations measured at  the axle would have
to be 20 dB higher than those he measured, to make carcass vi-
brations a significant factor.
  This result is only approximate.  It is based on assumptions
regarding the relationships between axle motions and the vi-
brations of the tread.  Moreover, the amplitudes of tread and
carcass vibrations are dependent on the tread pattern and the
roughness of the rosd surface. Consequently, tread and car-
cass vibrations are not ruled out as a significant source of
sound in all cases. B'j1 this  result indicates that there may be
son:.- czxs at least where tread and carcass vibration are  not
significant.

AIR PUMPING

  Another source of air displacements may give rise to audible
sound  Ths source  t>  zssi-.ciatcd with deformations of tha
trc.id which c^mot  K1 cl issified properly ;is tiejd  or carcass
vibrations. When a portion  of the tread rolls into  contact with
the road surface, it is compressed radially, transversely, and
longitudinally. This compression forces air out of \}\t trc?d
voiJs as ilw volume ol the voids is reduced When Hit iw.'d
rolls out of contact, the compression is relieved and air f!cvv»
back into ths expanding voids.  This action of forcing a:i out
of and into tread voids is called "air pumping."
  The sound prcssuie luel generated by Ihii time-varyin; rate
of airflow can be appioxjrnated by a  monopcle acoustic
source. The acoustic pressure generated by a simple inonopole
source is given by the expression
                  p(r.O
                                 bi
0)
 where.
            p(r, t) = acoustic pressure at a distance "r" from
                    source at time "t"
               p - density of the air
 (dQ/dt) (t - (r/c)) = time r:te of change of total airflow »
                    source
                c - velocity of sound

 This expression shows that the acoustic pressure is a funciion
 of the rate of change of the airflow at the source at a tiire
 interval r/c earlier. This expression assumes a free field around
 the source.
   Simple monopole acoustic sources zre omniu'.rectioni!  Tus
 is apparent fro:n Eq. 1   Air pumping does not necessarily give
 ris.' to an omnidirectional ound fi;ld. ihts is simply a copse-
 quenfj of tins approximation. Presumably, if j.xact ir.fcrmi-
 tior, were available 0:1 the deformation of the tread voids, i
 superposition of simple nionopole so.jr:es could be used :o ob-
 tain a bitter cpproxhmiion. which woi.ld include the dirjc-
 tioi.ility of the sound procjced by rssns of tiJs mechnr :»m.
   Tne expression  for a simple monopoly source can be i-$;d to
 calculate the sound level produced by an purr.psng. The cd-
 cubtion is performed by fust wriUrgout ths e\pression for
 the mean value of the squire of the acoustic pressure for a
 simple nionopole source:
                                                       (2)
 All t!int is needed now 15 an estimate for 3Q/ot in term.1! of the
 physical dimensions of the tread pattern and speed of tin- tire.
 Hav den (2) worked out  such an estimate and obtained an ex-
 pression lor ths sound level in decibels.

    SPL(r) =  6S.5 +  20Io:
-------
                                        r-3
Fig. 3 • Definition of tr:id parameters for tile calculation of the sound
pressure levels resulting from air pumping in tread voids (sec Lq. 3)
      n = number of voids across tread
   f. c. = fractional change in void volume
     V = (forward) translalional velocity of tire

See Fig. 3 for a schematic representation of these parameters
(2) and also "s" (circumferential width of uead voids) and R
(tire radius).
  Hayden also determined the sound pressure level to be ex-
pected from the pumping of air in the voids in the surface of
the road.  This expiession is analogous to that  for the tread
voids:

        SPL(r) = 68.5 + 20 log(dr%vr/Sr)  + JO log m

                  + 201og(f.  c.) + 401ogV- 20 log r     (4)

where:

SPL (r) = sound pressure level, dB
     d  = depth of road cavities
    wj. = width, of cavities
     Sf = spacing of cavities along path of lire
     m = number of cavities per width of tire

  These expressions indicate that the mean squ.ired acoustic
pressure is directly proportional to the number of voids across
the tread, the square of the void dimensions, the square of the
fractional volume change during deformation,  and the  fourth
power of the velocity. The mean squared acoustic pressure  is
inversely proportional to the square of the distance between
the source and the observer. This is the expected result for
transmission in a free field.  The predicted velocity depen-
dence holds, provided the deformation of the tread elements
does not charije with speed and provided the How of air for a
given volume change is not altered by speed-dependent effects
such as inertia.
  Nonunifornulies in the tire aho affect the air-pumping
mechanism by changing  the deformations in the tread. The
first harmonic of the radial force vatiaiion.  fur example, can
give rise to a o:ice-per-revolution variation in the  normal load.
This would e.iiisi* the amount of deformation in the trend to
vary as a fii'iction of position around the lire.  'Ihis. in turn.
would give rife to  a variation in the ir.-.ctional volume change
of the trend  voids  around the tire. The result would bo a once-
per-re volution  vacation in the rms sound pressure level. This*
phenomenon is called "flicker." by jn.ilogy with  .1 similar
phenomenon in the case of light.
           ^o
                      30      40    £0   CO
                  V'VEHIClE SPEED (MILES/HOUSI
                                              73  60 SO
 Tig. 4 - Predicted contribution of various source mechanisms to road-
 side noise
RELATIVE CONTRIBUTIONS OF THE  MECHANISMS
OF TIRE  SOUND GENERATION

  Hayden found that the sound pressure levels calculated from
Eqs. 3 and 4 are in good agreement with the measured values
for both rib rind cross-rib tires.  Fig. 4 shows Hayden's calcula-
ted sound piessine levels as a function of speed for ouch mech-
anism of sound generation (2).  Note  that the  con'.iiluuion of
tire vibrations and of the aerodynamic sources ?re small rela-
tive to the  contribution of air pumping.  The sound mecha-
nisms identified in Fig. 4 by number are:

  1. Truck cross-rib or auto-snow tires.
  2. Motorcycle cross-rib tires.
  3. Passenger rib tires,
  4. Roadway noise, concrete.
  5. Roadway noise, asphalt.
  6. Aerodynamic? sources.
  1. Vibration of passenger tire on concrete.

  The agreement between Hay den's calculated values and
Tetlow's (3) measurements of truck tire sounds is very good.
The speed dependence of the sound levels exhibited by tires
in Tellow's sample is closely approximated by the 40  log V
dependence. This 40 log V speed dependence  is also demon-
strated by other measurements.  Fig. 5 shows the  speed depen-
dence exhibited by a sample of tires tested by  DOT (4). Tills
group of five tiies :ilso exhibits a speed dependence that is
closely approximated by 40 lojj  V.  The sound lewis of cross-
rib  lires increase somewhat faster th:;n 40 U'g V, luit tins ns:iy
be caused by the A-\veishting network.  At lo\v >;veils, the
major peaks in the sound spectrum of the cross-rib tires occui
nt lower frequencies and arc  attenuated moie by the A-u.e:;:!ii
ins; lietwork.
  The close agreement between  the experimentally determined
speed dependence of tiie sound  levels and the  speed depen-
dence predicted foi Ihc air-pumpi1.* mechanism is ftiiilui evi-
dence that ;iii  pumping is an  impoiumt mechanism for numy

-------
8
             •OT-
          IS 90-
                                                                     TaWc t - Relative IVik A-^Vci.-'nerf Sound Ixwi&of
                                                                                  Various Yit-'k liu-i*
                    30       40     60    (0
                        VEHICLE SPEED (UPHI
Fig. S - Peak A-woighted sound level as a function of speed measured at
50 ft (30 m). A and B, rib tires; C and D, cross-rib tires; E, pocket re-
Iteid

tires. The sound pressure levels contributed by each mecha-
nism of tire sound generation depend, of course, on the phy-
sical characteristics of the tire and of the road surface.
Furthermore, the conditions under which the (ire is operating
will affect the contribution of each  mechanism.  The effect
of some of these factors will be considered next.

EFFECT  OF TREAD PATTERN  ON'  TIRE
SOUN'D  LEVELS

  The contribution of each mechanism of sound generation lo
the total sound generated by  the tire depends on a number of
tire features-  tiie  tread pattern, the  carcass construction, the
construction  materials, etc. It is instructive to consider the
effects of major changes in the tread pattern.
  Consider first a tire with a smooth tread.  The smooth tread
should be the quietest, since there are no tread elements to
excite carcass vibrations or to increase air turbulence and there
are no tread voids to contribute to air pumping.  This predic-
tion is verified by measurements of the peak A-weighted sound
level exhibited by a tire with  a smooth tread.  Measurements
for different  tread patterns are reported in Table 1. The data
for radial and bias tires are not directly comparable because
these tires have different tread patterns.
  Consider next a tread pattern consisting of straight circum-
ferential grooves that run parallel to each other around the en-
tire circumference of the tire. If each segment of a circum-
ferential groove is deformed i;i the same way as it goes through
the contact patch, the groove will always appear to be the
same when viewed from a frame of  reference moving with the
tire. This is analogous to the case of carcass deformations that
do not change. The  pumping of air into and out of the groove
will contribute only  to a slowly varying pressure disturbance
as a function of the space coordinates around  ihe tire.  This
pressure distrui'unce does not contribute uuuibl-.- s;umd.  Hut,
if there is a variation in the groove deformation, air pumping
associated with tlut  variation will contribute audible sound.
The circumfciential grooves may  also contribute to slightly in-
creased air turbulence.
                                                                                               t; A-\Vcr.!il ;<" 1-ouiid Level,
                                                                    Tttc Type
                                                                                                             Concrete
Smooth licaJ                          65.9
Smooth Head
 drcumfcrc;Hi::!lr grooved              67.3
Bias-ply rib                            68.4
Kndul-ply lib                          699
Hiis-ply ctoislvr                       75.8
Radial-ply crossbar                      72.1

 •Tireitafa: 10.0CN23, toad rj:i;'.: I". Tc>t cunditi--.r
SAE Rccommrnu Jtl Practice fir iht Measurement o!
 Source: "Tiutk Tire Noise," Kubcor Manufacturer*
November 1971 (3tf. S).
                                                                                                               66.9

                                                                                                               68:2
                                                                                                               70.5
                                                                                                               71.3-
                                                                                                               79.9
                                                                                                               75.7

                                                                                                         : Cur-furm fa
                                                                                                         Tru.'k Tut Xoiv:
                                                                                                             >ei.tlit>ir.
                                                               This analysis indicates that circumferential!}' ao.ived trcjds
                                                             should exhibit slightly highes souud levels than r-wooth treads.
                                                             This expect a lion is verified by the data reported in Table I.
                                                             The circumferential grooves iv. \. however, h.v-e the effect  of
                                                             reducing the sound produced i-v the air displaced from load
                                                             surface cavities. The circiKiiier-.-i:tia! grooves v.otild not allow
                                                             the road cavil:;* so be sealed ;•.;> '•• '!! i;s they  * «.'u!J be by the
                                                             smooth tread. Cuubequjnily. t!.e relative sounJ lewis exhibi-
                                                             ted by smooth and circumfcrontialiy grooved tieads depend i>n
                                                             the road surface.
                                                               Consider next the two types of trend patiorr.r- iu>!!n.i!ly u^e-d.
                                                             on truck tires dcsigiied for highway use.  The r:b-:re;:d pa tier n
                                                             consists bssic.iliy of circ\i:ri!crer.i;ul ribs with iav iooth edges.
                                                             Tins type of ticad pattern resen'.L'Ls that of a pa^oncet car
                                                             tire except th::t Ihe sawtoo>h cdces are. longer Hid (he gioovos
                                                             are larger. Tiie cross-rib (or cro>ib:sr or lug) tre;'d pattein lias
                                                             lateral bars and lateral voids extending from the shoulder
                                                             toward the ccn lei line of tiif tread.
                                                               Both designs may incorporate varying amounts of Uerfing
                                                             (siping or bladfnu) to improve v.et traction.  One of the pri-
                                                             mary functions of both types of tread patterns is la increase
                                                             wet traction. The cross-rib tire is generally used 0:1 dtive axles
                                                             because of its superior traction and wear in tlut  application.
                                                               The tread elements in these tread designs contribute to car-
                                                             cass vibrations and to increased .n.ir turbulence.  The tread
                                                             voids contribute to air punuiine..  In general, hrger trend cle-
                                                             ments produce brgsr carcass vibrations and  ir.cre nil turbu-
                                                             lence.  Larger tread voids produce higher sound-picture levels
                                                             due to nir pumping..  Conseqi'.eiuly. cross-rib tires wotsld be: ex-
                                                             pected ii> exhibit l;irjicr sound levels  than lib tiros because the
                                                             cross-rib tires generally ha\e Lu^-r tread  clemonis. This ex-
                                                             pectation is verified by ihe sound levels reported for lib and
                                                             crowbar tiros iiiTiblo I.

                                                             LI I LCT OF  C.l'L-.RAIING CONDITIONS ON
                                                             TIRE SOUNDS

                                                               SPEED - The sound level exh^iieil  by  a tin- increases with a
                                                             speed.  The simple monupole source anproxiniation predicts

-------
         lOiD P£R i'-.E.N
        Mn «:y:  tiauqa,
       «ooo  6x0
          LOiO F-R -'-• (ISO
f\f. 6 • Peak A-wcidiied
sound level as a function of
loud on the drive axle mej-
surcd -jl SO ft (30 in) with a
vcliu-l; speed of 55 mr-h (88
km/h)
Ilia! the contribution due to air pumping increases according
to the 40 log V te::n.  Hayden's calculated contribution of tlie
aerodynamic sources increases at an even faster rate, but ex-
hibits a lower leve! except at very 1115!) speeds,  Based on llie
accelerations measured at the axle, the contribution of tread
and carcass vibrsiio.-is should increase more slowly with speed
ti:2:i the consributu-ii of air pumping (see Fig. 4).  Measure-
ments of tire sour.d levels as a function of speed closely
approximate th: 40 log V speed dependence.
  TIRE LOAD AND INFLATION PRESSURE - Chances in
loud iiid inflation ;.-re?sure which increase the tread deforma-
tions* and l\\: carets vibrations will increase the sound level
generated by the lire (6). Increasing the load at constant in-
flation, pressure. rVr instance, will increase  the deformations in
the tread and will increase the trend and  carcass vibrations.
This will increase the sound level. Fig. 6 shows the effect  of
load on the  sound levels produced by a group of tires mea-
sured by DOT (4). Tiie tires involved in  this test were:

  1. A and C, new rib tire.
  1. F, new cross-rib  tire.
  3. C, half-worn cross-rib tire.
  4. I, half-worn retread.
  5. H, new retread.

  ROAD SURFACE -The road surface affects the way in
which the tread elements are deformed in the contact patch
and the abruptness with which they break contact with the
surface when they roll out of contact. When a tread clement
is released abruptly with a snapping action as  it leaves the road
surface, the bQ ci will be larger  tlun if that clement  is released
slowly and uniformly. Since the acoustic pressure is  proper-
iir:ip.l to ?Q ii. i' .„* sound prcss.iu- level will be higher when
the tread eleiv.i.;-.; is released abruptly . Furthermore, a
snv.o'.h, uniform ro;;d surface peimits better sealing of the
tread elements ;round the voids. Tiie release  of well-sealed
tread voids  v.i'.l civv rise to larger values  of 3Q/Ot. Conse-
quently, smooth si.rl.jccs tend to increase the sound pressure
level pcr.e rated by the Ui.iJ voids, especially if they promote
abrupt releuie of tirj treed elements.
  The cavities in the itcd .surface generate sound by iuc.r;\w:
air-pumping mechanism. b:;t the to^d cavities a!>o can reduce
the sour.d generated by !l:e tread voics !»> reducing dQ'o;.
The ei'u-ci  ihat predominates will de;.;."d on ilia tread pa::-rn
of i!v: lire. A smootli ro^c surface v.iii have the largest eiu-ci
on cup- type treads, wlsui, -.cud to se.il very v-eli on &nior>:l>
surfaces.
  Tlie sir-pumping mechnriism depends on the tread void*, li;*
road surface cavities, auu the iniertciion between them-. The,
ro2d surface asperities a! so affect ll.e  ireud and carcass vibra-
tions. This results in a very complex effect of the ro^d su.-fao:
on  the sound level gei;-?r.i;ed by the ;i:e. See Table 1 foi a
compaVison of a concrete and an asr-'..:h suriace.
  BRAKING, TRACTIVE. AND CORNERING FORCES -
Forces acting  on the tire (such as broking, tractive, and cor-
nering forces) also affect the deformations of ilia tread ele-
ments.  Tiie alteration of the (read cetbrnuiions probubiy h^s
the greatest effect oil tl.e sound gcner.-.ted by .T.earts of t'r.e
air-pumping mechanivm. Tliere is no  definitive data avuilible
on  ihe effect of these fV-iceson  tire sound levels, but the sound
produced by the atr-pumping'mechKiiissn should be dependent
on tlie fractional cluin;;;- of the tread-void volumes. Con<--
quer.ily. the application of forces ::i3! increase the frucii.-r.jl
volume chiu.ce of lii; tread voids shw.ild increase the s-.>.!:-.u
level  exhibited by the lire.


SPECTRAL DISTRIBUTION OF TIRE SOUNDS
                              \Vhen the spectra of tire sounds sre measured by a sl2t:.T.::ry
                            observer along the roadway, the spectra are complicate-.! by
                            the relative motion of the sound source in relation to the ob-
                            server.  These complications arise as a lesuli of the Dopplir
                            affect and  the spaiinl dependence of the sourd spectiu::: ex-
                            hibited  by the tire. Furthermore, the changing i!iten>it> of the
                            sound as the distance to the tire changes poses tfddition.il
                            practical problems foi spectral measurements made by a
                            stntiqnruy  observer. Consequently, the investigation ol lire
                            spectra is greatly simplified by considering the spectni:r. a: a
                            fixed position relative to the tire.  Additional simplified Ion*
                            result from considering a tire running at constant speed.
                              The acoustic pressure variation at any given position re5.i!.ive
                            to the tire  will have two components.  One component ii
                            periodic, with a period  corresponding to one rotation  01 rhe
                            tire. The other  component is aperi.-dic.
                              THE  PERIODIC COMPONENT  OF  1 HE ACOUSTIC
                            PRESSURE  VARIATION - The periodic corrpcik'iii is •': •:
                            p.irl of the acoustic pressure vari.mon  th.it repeals the >~:r.-'
                            waveform- that is, lime dependence- with each rotation or n..-
                            tire. The tread  put torn ;:nd tire nonumforr.-.ities are the tire
                            chur.vtcristijs t!::it contribute to ti.e poiio^c  com;->'-:-.".i.
                            Tlie trend  pattcin at-.J tire nomniifjrmilies contribute ; -
                            same acoustic pressure  variation for each roiation ot i:.c :;:c.
                              'Ihe spectrum of the  periodic component of'ihe aco.t-:ic
                            pressiue variation is discrete. This component exhibr.-.- :•' i:>w

-------
10
energy only at the discrete frequencies fk, given by the equa-
tion

                               k
                          k "  f
                                                      (5)
where T is the period of rotation of the lire and '"k" is :-!iy
positive integer. The amount of sound encray at each frequen-
cy fj., k = 1,2,3 .... is determined by the spacing of the
tread elements and nonuniforniities around the circumference
of the lire.
  The amount of sound eneuy is usually large for value* of
"k" that are close to mtegial multiples of i!ie number of tread
elements. K.  For a tire hiving  100 tread e'.e;-ints around its
circumference, the sourd energy at fk for k * K = 100 v.oiild
be large. Furthermore, the sound energy at fj.. where k * 2K
= 200, k * 3K = 300..... would also tend to be large.  If ihe
tire in this example were traveling at a sp:ed correspond1.',: to
10 rps, the sound spectrum of the tire would exhibit peaks at
1000.2000,3000 Hz	since
                  '100
JOO
O.ls
                       = ^ •=  1000s'
                                      -1
  The spectral p?ak at 1000 Hz in this ex.nrple is often called
the fundamental of the tire sound. The peak at 2000 Hz is the
second harmonic, and the peak at 3000 Hz is tl.e third har-
monic, etc.  Note that the frequency of each lurmonic is di-
rectly proportional to the tire speed, since fj. is m\crse!> pro
portiona! to the tire rotational penod.
  Large peak* in the sound spectrum of a lire are undesirable
bccausi they cause the so-.:nd to be more ho-.ic.'able and p-o:e
annoying. For this reason. the tread cleme;:1. *,\ijmgs are
varied in such a way as to minimize the peaks il-.st norm:'ly
occur at the fundamental frequency and at the higher har-
monics of tlm fundament.!! frequency (7)
  THE APERIODIC COMPONENT OF THE ACOUSTIC
PRESSURE VARIATION • The aperiodic component of the
acoustic pressure variation exhibits a continuous spectrum
This component is generated by the randoT. contributions of
the road and of air turbulence. Although  these contributions
are random, they still nuy exhibit spectral peaks.  The sp?emgs
of cavities in the road surface, for instance, may be random
and yet still exhibit a statistical distribution of >.\ici:igs about
some mean value.  If this dif.ribution is s'iarr-!>  peaked, it
would give use to a sharp pe,ik in that part of t! e sound spec-
trum contributed by  the c_\ities in the rocd >urf:ce.
  PERIODIC AND APERIODIC COMPONENT S OF LACII
MECHANISM OF SOLND G!:NLRATION • Lic\ ir.«har,'>,i:
of tire-sou:1.!] generation co: iiibutus to bo.ii t'.e periodic
component  aiiJ the ap^ioJ.c component  ot ic.i PCOUSUC p:o»-
sure variation. Air punipr'f and carcass vibrations renerau-
periodic pressure van.iiiv.-i.- -< a result ofi:1^1.!^ MSH tl e  t'.vd
pattern an.; lire nomir.iioiiii.iu-k. These hieciui'.isim geiii.-i.uc
aperiodic pressure variations as a result ot roail i;:puls.  Aero-
dynamic sources include random air turbulence and penoJic
an  tuibiiL-nce associated -Aall the ticad pitterii
                                    DlllL'Cl IONALITY - Hacli mechanuni of tire sounJ g.
                                  tion rsdn'.es sound in preferred directions dif.T.ding OP. 'i"
                                  design of the lire. This  factor, together wtih ti'C interfer. •..•
                                  between sounds orignutir; at difteicnt pjrts •>( ti\o ti:o LIU!
                                  reflecliiij from surfaces around the tire, STV-.-S r-se to a spec-
                                  trum thai is a function of position arovind the lire.
                                    RELATIVE MOTION tiLTWLEN'THF.llKC ANDTIIE
                                  OBSEKN I'.R - The effeci> of relative inotisi, t.-tween tl:c ii. :
                                  and the observer are nov% apparent. For a stati-inary ob;;• .cr
                                  along the roadway, the s;»2ti.:l dependence of tiie ipecti j/i
                                  gives riie to a spectaiin  th::t ch.ingis with time is the tire
                                  passes by  The frequcncv of the Fcaks in tire co-jr.d specira
                                  associated with the tread pattern, lire noiiiinifu'iiiities, ?'.-1:
                                  road surface are directl> pioportional to the sp;:J of liie ;.'.--.'.
                                  The frequenc>' shift due to ihe Doppler efloc: is given b> n e
                                  equation
                                                                                        (6)
                                  where:
                                                           f = frequency measured by stationary observer
                                                            f = ficquency in frame of reference of tire
                                                           v - component of tire velocity toward or awcy from ob:?:»fi
                                                                (minus sit-n for motion toward and plus s ^ i lor mo;:o:.
                                                                avvjy from observer)
                                                           c = speed of sound

                                                           SUMMARY

                                                             The ro'.h.ig tire displaces ,iii by means of lr.!.-.f
                                                           the sound field around the  me causes the spectrum 10 charge
                                                           vvnh time n> ihe relative positions of the tire  and ihe observer
                                                           change. Ihe Doppler etfect contributes an arluiuo-v.l sh:l::::
                                                           frequencies, v. liich changes r^ the :eljtive po>;tu i' of (he t.re
                                                           and  the pbcrver clunge  The situation is Minpi'feu by cor-
                                                           sidennj; the spectrum in the fr.-.me ot relcieno? o.' ti:e lue.  1'.
                                                           thib friinv oi'icfercnce. ihe Head pattern and tiro nonumform-
                                                           ities are fou-.J to contnbuic .1 periodic acouxiic--:ir:s?iire \ ••'.--
                                                           nor  The ii»'J surt'.'.ie c.'.\:iiib :'ivJ the rnndoi.'  •. :^ib:''c .v.-
                                                           coiitrihuie .in aperiodic iico|j>tic-pressurc v.'.ri.ition. The pcr:-
                                                           oJic compv'. ^nt exhibits spccir.il  pe.'ks at discrete freqi.cr.ci '>>
                                                           and the jpen^dic component exhibits a cmiii.iuouk M*CI"'.: i
                                                           The frequencies of spectral peaks proJiikCd by  il>c irca-J •,&-

-------
                                                                                                             II
lern, the ro..d s. (face caviti.-s. i. -,c! t!ie UK nn;uinforni!ties an:
directly proj-oriionsl to the tire sused.

REFERENCES

  1.  W. R. Ss-sis (cd.), "Theory nf High Speed Acrcdy-
namics." I'rsi.cion, N. J.: Pni'.icioii Univeruiy Fuss, 1954.
  2.  R. E. H.IJ den. ''Roadside None from the Interaction of a
Rolling Tire >.u!i the Road Sv.rfi.-e." Paper printed at tlie
81st Msetip.: of the Acoustical Society of AiiKuci, Washing-
ton, D C.,
-------
                             Reprinted by Permission
                             of Overdrive Magazine
                                            97
Quieter Truck  Can  Mean More Profit

A  Modulated  Fan  Clutch
Will  Pay For   Itself  In  Less  Than   A  Year
    . method of saving truckers hundreds - no, thou-
sands - of dollars a year has been known by trucking
engineers for years, but has been ignored  by many,
due to the initial inconvenience of installing it Since
fuel  costs have doubled  in the past two years  and
strict noise emission standards have been imposed on
trucks, this money-saving device will help truckers
fight both these problems
  The fan on  the  diesel engine doesn't look like  a
potential gold mine to the average independent truck-
er, but it is. Most owner-operators feel that the fan
must spin whenever the engine runs or else the engine
manufacturer wouldn't have put the fan on his diesel
engine in the first place. Right? Wrong. In reality, the
fan on a modern diesel engine installed behind a large
radiator isn't needed except for a few miles a day. The
reason that the engine manufacturer puts the continu-
ous drive fan on the  engine is because it is cheaper
But  that same fan is robbing you of dollars and horse-
power every day that it is allowed to run all the time.
   So a group  of engineers decided  that  if the fan
weren't needed all the time, why not invent a method
of just having the fan cut through the air only when
the  water reached a  certain  temperature. The  rest
of the time  it  could just sit idle. It  didn't take too
long until various methods of disengaging the fan were
perfected, but  unfortunately,  it cost  more money to
have the fan engage and disengage itself automatically.
This  cost penalty -  around  $500  -  was always
thought  too great by all but the most cost-conscious
truckers. Well, now that the price of fuel is consistent-
ly above 40^ a gallon, truckers should ask what is this
modulating fan and how does it save money9
   The aggressive  fans used by the new high horse-
power engines  dram up to 25 horsepower to keep the
engine cool during the worst possible conditions. What
a fan clutch  does is to determine when  the fan  is
really needed - which is, in reality, very little - and
 to turn it on or off  By disengaging those big metal
blades  from cutting  through  the air,  the trucker
doesn't waste  that 25 horsepower driving  something
that isn't necessary, and  can apply it where it can do
more good -  such as at the  rear wheels  Also, that
fan  forcing air into the radiator makes a loud noise
By switching the fan "into neutral," the trucker can
quiet his truck on the inside of the cab as well as on
the outside.
  But what really should interest a trucker is the fact
that every reputable study that has been made in the
past few years has shown that the installation of  a fan
clutch will save the owner thousands of dollars over
the  life of the diesel engine. There arc several manu-
facturers of fan clutches for heavy-duty diesel trucks
today. Rockford, Schwitzcr, Hoi ton. and Eaton, just
to name a few. They can all produce scientific data
to prove one fact   You don't need to  turn the fan
continuously The fan should be engaged only when
it is absolutely necessary
  If these facts are so well known to truck engineers,
why in the  world haven't you been  told this in the
past, and why  aren't you driving a truck equipped
with a  fan clutch9 Here is what  the federal  govern-
ment found out when it studied that very question
The Environmental Protection Agency  found  that
"Not only can fan clutches reduce noise but  also re-
sult in  significant fuel savings A  review of the past
market acceptance of fan clutches puts the potential
benefits of fan clutches in  perspective  Historically,
most truck  owners have not installed fan clutches or
have not been able  to take advantage of the fuel sav-
ings if they were installed  Fan  clutches have had
several technical  and reliability problems that  ham-
pered their use, these problems arc now considered to
be solved. Truck owners who have installed fan clutch-
es have preferred to increase speed and payload rather
than save fuel due to the lowered power requirements
Currently, approximately  5% of heavy-duty trucks
are fitted with fan clutches "
  All the  talk in the world about  modulating fan
clutches won't cjusc an independent trucker to install
one unless he is sure that it is vutually guaranteed to
save him money or give more horsepower  So let's
look at the statistics presented by  the  Borg-Warncr
Corporation when testifying February 20, 1975, before
the Environmental Protection Agency in Washington,
DC They introduced evidence gained by two  cross-
                                       OVERDRIVE  APRIL  1975

-------
98
                                                                   PISTON HOUSING
              OIL COOLER
                 PULLEY

             CLUTCH BODY
              PITOT TUBE
                BRACKET
         BELLEVILLE SPRING

           THRUST WASHER
     AIR FROM VEHICLE SUPPLY
         THERMAL AIR VALVE
                                                                                      BEARING RETAINER
                              BELLEVILLE SPRINGS



                              FAN SHAFT

                              HUB

                              FAN MOUNTING HUB
                              INTERNAL SPLINED PLATES
                              BACK PLATE


                              EXTERNAL TANGED PLATES
                                                        AIR TO CLUTCH
                                                                        -PRESSURE PLATE
country, heavy-duty diesel trucks taken at random
from the Borg-Warner Transportation Services fleet of
51  trucks.  These  were not  stripped  down  "fleet"
trucks. The units utilized in the test were 1974 Peter-
bilt three-axle tractors, with Cummins NTC-350 pow-
er,  a Fuller RTO-12513 transmission, and sporting a
4.1 1 rear axle ratio. These tractors equal the specifi-
cations of most independent truckers running the high-
way today. Trailers used in the test were 40-foot van-
type with an overall height of 12' 6" and tandem rear
axles.
   The tractors were tested in the following manner:
For the first six months of operation (January through
June, 1974), a fan clutch was not used. The solid fan
drive,  as  installed  by the engine builder,  was used.
Then,  for  the next six months of  operation  (July
through December, 1974), a Rockford variable speed
fan clutch system was operated on the Cummins 350.
Over the year-long test, the cargo carried consisted of
automotive parts, castings, and forgings with the pay-
load averaging 34,376  pounds. Using a rough figure of
28,000 pounds for the tractor-trailer combination, the
average gross cargo weight was 62,376 pounds. The
total distance traveled in 1974 by the two trucks was
1 16,572 and 97,557, respectively. For about 10%  of
the miles, the tractor-trailer combination was running
empty. Each truck was used in nationwide interstate
commerce  operations with  fuel being purchased  en
route as required. Fuel prices varied  from 34.2 cents
per gallon in New Mexico to 56.5 cents per gallon in
Mississippi,  with  the fuel cost for the  year averaging
48.4 cents a gallon.  The truck that  logged 1 16,572
miles averaged 4.010 miles per gallon  with the con-
tinuously  operating  fan  and 4.329  miles per gallon
with  the  Rockford modulating fan. The other unit
averaged 3.870 mpg with the  fan engaged continu-
ously and 4.174 miles  per gallon after the Rockford
fan clutch was installed.
   Looking  at the chart, you can see that the differ-
ence over a  year's period of operation  would amount
to a savings of 2,142 gallons on one  truck and  1,837
gallons on the other. Using a figure of 48.4 cents per
gallon, this  would amount to a savings of SI,036 per
year on  the first truck  and $889  per  year on the
second truck. And these figures accept the fact that
the oil  companies and  Congress have  already  been
                                           OVERDRIVE  APRIL 1975

-------
                                                                                                      99
Truck Number
21PD26
1 . Gallons of fuel used per year without 29,070
Rockford Clutch fan drive (1 16,572 mi es
@4. 010 miles
per gal.)
2. Gallons of fuel used per year with 26,928
Rockford Clutch fan drive (116,572 mi es
@ 4. 329 miles
per gal.)
3. Gallons of fuel saved per year 2, 142
4. Price of fuel per gal Ion $ 0.484
5. Dollars Saved per year $ 1036.72
6. Approximate retrofitCost of Fan Drive
(Includes Installation Costs) $ 540.00
7. Profit Increase Per Year
First Year (Line 6 subtracted from Line 5) $ 496.72
Second Year (Line 5) 1036.72
Third Year (Line 5) 1036.72
Fourth Year (Line 5) 1036.72
Total Profit Increase Over Four Years $ 3606.88
8. Gallons of Fuel Saved Over Four Year Period 8,568
Truck Number
21PD32
25,209
(97, 557 miles
(fr3. 870 miles
per gal.)
23,372
(97,557 miles
@4.174mies
per gal.;
1,837
$ 0.484
$ 889.11
$ 540.00
$ 349.11
889.11
889.11
889.11
$ 3016.44
7,348
planning ways to get up the price even higher.
  Subtracting the  cost of the fan clutch (estimated
at $540 by  Rockford) from  the  first year's savings,
the fleet saved approximately S500 on the first truck
and $350 on the second. And then, for every other
year that the truck is run, a savings of from S889 to
$ 1,036 is realized These figures submitted to the EPA
don't estimate  any  maintenance  costs on the fan
clutch,  but  a trucker certainly  would have a lot of
profit from  which to spend money to maintain this
valuable piece of equipment.
  The Rockford fan drive clutch  is a compact, spnng-
loaded,  oil  cooled,  multiplate  clutch   designed for
continuous infinite fan-to-engine-pulley-speed ratios,
assuring prescribed engine coolant temperatures and
minimum engine horsepower losses, according to Borg-
Wamcr  What that says in trucker-talk is that it enga-
ges itself and disengages itself as  it is needed, and the
working  parts are lubricated  by air-cooled oil. The
fan knows when to work harder by signals sent to it
by a sensor mounted in the engine cooling system. A
thermal air valve senses when the engine is operating
at normal temperatures and the fan is not needed.
This valve directs air from the truck air supply to the
fan clutch  and disengages the fan  clutch when not
needed  When the thermal  air valve senses that the
water temperature has  reached a point where the fan
is needed to cool the engine water, it cuts off the air
supply and allows the  fan to gradually engage again.
Thus if the air valve of the fan clutch is faulty, the fan
will operate like the continuous-drive fan supplied by
the engine manufacturer.
   How much is the fan really needed during the oper-
ation  of your tractor-trailer  combination' Well,  it
varies, depending on the size of your radiator and the
outside air temperature, but most engineers feel that
                                         OVERDRIVE  APRIL 1975

-------
100
 the fan is needed tor cooling less than 5% of the time
 Rockford told the EPA that "a fan clutch reduces the
 amount of time a Ian  operates at speeds which cause
 it to contribute to overall truck noise less than 1 per-
 cent of  the total hours of engine operations. In  its
 own background document  on noise regulations, the
 EPA  states  "Significant growth  in the fan  clutch
 market would appear likely, provided  that historic
 resistance to fan clutches is overcome. Federal noise
 emission standards could very well provide the impe-
 tus to accelerate widespread  fan clutch acceptance "
   One great impetus  that the federal government is
 providing is contained in the Federal Register dated
 February 28, 1975, on the subject of noise emission
 standards In describing the  truck noise measurement
 procedures that the federal government proposes, item
 seven would peimil trucks with fan clutches to under-
 go  the  lest while the fan clutch is  disengaged The
                     proposed rules even allow a trucker to run his engine
                     up  to  10 minutes to get the fan clutch to disengage.
                     The reason that the government feels that fan clutch-
                     es are valuable is contained in this same document in
                     item seven.  It states "It is apparent, therefore, that
                     installation  of radiator fan-drive clutches  results in
                     significant noise  abatement benefits as well as other
                     benefits. The noise reduction associated with installa-
                     tion of fan  clutches  occurs between 97 and 99 per-
                     cent of the time that the vehicle is operating "
                      If you want to have  a quieter truck, and also get
                     improved fuel economy or additional power 94 to 99
                     percent of the time, look into buying that next truck
                     with a fan clutch  Or even better, get a  fan clutch put
                     on your present truck and get a return on your invest-
                     ment in about six months  That's a lot better than
                     buying Savings Bonds
    STATE BY STATE LISTING OF THE HIGHEST AND LOWEST PRICES PAID PER GALLON OF
    DIESEL FUEL  IN 1974 BY  BORG-WARNER TRANSPORTATION  SERVICES FLEET
     State
Cost/Gal.
State
Alabama
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
Florida
Georgia
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
55.5$/49.9c
51.9/44.4
54.2/48.9
52.2/42.9
43.1/40.3
53.9/49.5
47.9/45.6
53.1/45.6
53.1/48.0
40.6/40.6
51.4/38.0
51.4/45.4
49.7/44.9
49.3/46.9
50.8/47.7
50.5/47.7
—
53.0/48.7
52.9/42.9
51.9/46.1
44.8/44.8
56.5/52.4
Cost/Gal.
Missouri
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
Ohio
Oklahoma
Oregon
Pennsylvania
South Carolina
Texas
Tennessee
Utah
Virginia
Washington
West Virginia
Wisconsin
Wyomi ng
49.3/43.9
49.9/45.6
44.3/39.9
—
48.6/45.3
47.0/34.2
54.0/47.0
54.0/49.4
50.0/46.4
51.7/40.2
46.3/46.3
49.5/44.9
52.6/46.4
50.5/44.5
54.2/46.7
48.4/42.0
51.9/45.4
—
52.1/41.9
50.5/44.7
41.1/37.7
                                        OVERDRIVE  APRIL 1975

-------