Environment
Aljt.MICV
Washington DC
oise, Idaho
Boise Community
Noise Survey
-------
EPA 550/9-79-402
BOISE COMMUNITY
NOISE SURVEY
MAY 1979
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF NOISE ABATEMENT AND CONTROL
Washington, D.C. 20406
-------
Table of Contents
Section
FOREWORD v
ACKNOWLEDGEMENTS vi
TABLE OF CONTENTS iii
1 INTRODUCTION 1
1.1 General Noise Climate 1
1.2 Major Noise Sources 2
1.3 Recommendations 2
2 INTRODUCTION 5
2.1 Background 5
3 THE NATURE OF COMMUNITY NOISE 7
3.1 Nature of Community Noise 7
3.2 Measures of Community Noise 8
4 PROGRAM STRUCTURE 4
4.1 Goals and Study Area 4
4.2 Measurement Site Selection 4
4.3 Noise Measurement Methods 15
4.4 Data Reduction 17
5 RESULTS AND RECOMMENDATIONS 19
5.1 Results and Conclusions 19
5.2 Recommendations 33
REFERENCES 39
GLOSSARY 41
111
-------
Table of Contents
Section
APPENDIX A - SURVEY METHOD A-l
APPENDIX B - DATA REDUCTION AND ANALYSIS B-l
APPENDIX C - EQUIPMENT DETAILS C-l
APPENDIX D - DATA FORMS AND INSTRUCTIONS D-l
APPENDIX E - 24-HOUR DATA E-l
IV
-------
FOREWORD
In conjunction with the Ada Planning Association, the United States
Environmental Protection Agency (EPA) through its Office of Noise
Abatement and Control and its Region X office inventoried the noise
climate in Boise, Idaho to test the accuracy of a physical measurement
protocol. EPA hopes it will become part of a broad technical assistance
package available to communities who may wish to develop or improve a
noise control program. Based on the Boise results, the spatial sampling
method will be revised slightly so that the sample will better represent
the real noise climate.
-------
ACKNOWLEDGEMENTS
EPA would like to thank the following for their help in this project.
City of Boise
Ada Planning Association
Boise State University Urban Research Center
Boise State University Student Volunteers
Borah High School Ecology Club Members
Without their time and effort, this project would not have been successful
-------
1 INTRODUCTION
A noise measurement survey was carried out in Boise, Idaho to
(1) determine existing sound levels, (2) assist area planners, and (3)
develop a useful noise measurement procedure for use in other cities.
Survey results concerning the noise environment of Boise, Idaho are
presented.
1.1 General Noise Climate
In Boise, a city with a population exceeding 100,000, the average
sound levels for residential and park areas (L(jn values from 53 to 54 dB)
are near those of typical quiet suburban or small town environments. Sound
levels at night often diminish to those of the natural geographical area
without human activity (A-weighted sound levels to 30 dB). Thus, on the
average, it is a quieter place to live than would be expected of a city
that size. The industrial, commercial, and central business districts,
however, have average sound levels typical of a noisy urban environment
(L(jn 62-66 dB)*, and in places these levels decrease by only a moderate
amount even late at night. The airport influence area contains a region
/ ^*Jt
generally considered unsuitable for residential use (within the NEF-40
noise contour), although most industrial or agricultural activities would
be compatible with this area's average noise levels. The outer section
of the influence area (between the NEF-30 and NEF-40 contours) is margin-
ally compatible for residential usage, but the interior and exterior noise
* See Glossary
**NEF-Noise Exposure Forecast is a method for developing noise contours in
the vicinity of airports, contours generally range from less than 20 NEF
for lightly impacted areas to more than 40 NEF for heavily impacted areas,
-------
environments would be less desirable than those of other residential
areas of the city.
1.2 Major Noise Sources
The principal source of noise in Boise is street traffic. Approxi
mately three-quarters of the local noise intrusions occurring outside of
the airport influence area are due to cars or trucks, with an additional
10 percent due to jet aircraft and 4 percent to dogs barking. Even
within the airport influence area, over half of the intrusions are due
to street traffic. The average sound levels along principal arterials
and freeways carrying average daily traffic (ADT) greater than 6000
vehicles per day were significantly greater than those along roads with
ADT less than 6000 (10 dB difference in Ldn).
1.3 Recommendations
To preserve the low average residential sound levels and to pre-
vent growth of sound levels in industrial and commercial areas, planners
should consider limiting maximum ADT for major arterials through residen-
tial areas to below 6000. The use of multiple, low volume arterials may
be necessary to accomplish this as development expands further into the
foothills to the north and farmland to the southwest.
To remove some of the most intrusive roadway sounds, a vehicle
noise enforcement program could be instituted to reduce the sound levels
produced by heavy trucks. An enforced requirement that the A-weighted
sound level of a vehicle not exceed 86 dB at 15m (50 feet) when operated
-------
on a surface street would be consistent with regulations in effect in
other cities and States and would result in a reduction in sound level
of approximately the loudest 2 percent of trucks operating in the city.
Airport influence area development should be carefully planned
based on predicted future NEF contours. Residential development should
not be permitted within the predicted 1992 NEF-40 contour. Residences
constructed between the projected 1992 NEF-40 and NEF-30 contours will
require special sound-insulating construction techniques to attain
average interior sound levels equivalent to those in other residential
areas. Housing with limited outdoor space, such as planned community
developments or condominiums containing enclosed recreational facilities,
appear more appropriate for this area than single family residences with
large outdoor living spaces.
It should be noted, that these recommendations are made for the
sole purpose of controlling noise. There are of course, other factors
that must be taken into consideration, such as economic impacts, effects
on community growth, etc. Conflicts with the recommendations presented
in this report may arise, and where they do compromises will have to be
made.
-------
Boi/e ffletro floi/e monitor ing lo
-------
2.1 Background
Noise pollution can be a major contributor to the deterioration
of the quality of the community environment. This fact is best exempli-
fied by the Bureau of Census 1976 Annual Housing Survey, which showed
that Americans' biggest complaint about their neighborhoods is noise.
The survey revealed that 24 percent of America's urban households
feel that noise is the most undesirable neighborhood condition. By
contrast the other most commonly cited complaints were heavy traffic
(14 percent), street repair (13 percent), street lighting (9 percent),
and crime (8 percent).
Since noise is primarily a local problem, it is no wonder that
communities are beginning to take a harder look at community noise and
its adverse impacts. Understanding noise patterns and impacts enables
a community to effectively plan and manage land use and to deal with
significant noise sources.
Communities desiring to maintain or improve the quality of
the noise environment must first have an understanding of the existing
noise climate. A noise inventory (i.e., a survey of the acoustical
climate of the community) is the basis from which to determine the
need for a noise control program and the most effective measures (e.g.,
planning and legislation) for its implementation. The noise inventory
can provide city officials with a basis for exploring alternative
-------
programs for achieving or maintaining desired noise levels and for
forecasting future noise levels. In addition, it permits the validation
of noise prediction models. Finally, the inventory permits officials
and planners to gain a better grasp of how various levels of environ-
mental noise translate into community noise problems.
To assure that communities have a method or protocol to allow
them to effectively conduct a noise survey, the Environmental Protec-
tion Agency (EPA) has been developing a noise monitoring manual.3* This
project is one of several aimed at providing EPA technical noise control
assistance to communities interested in beginning or expanding a noise
control program. The noise monitoring manual had reached the stage of
development in which an interim protocol had evolved and required test-
ing. As the city selected for testing this interim protocol, Boise
offers a moderate size community having a climate that permits acoustic
sound level measurements in the month of January, a university having
an environmental sciences program to which the project could be tied,
and, finally, a city government and an area planning agency that realizes
the importance of preserving a quality environment.
*Superscripts designate references.
-------
3 THE NATURE OF COMMUNITY NOISE
3.1 Nature of Community Noise
Sound consists of small rapidly varying pressure fluctuations
that travel through the air and that are perceived to have the qualities
of tone and loudness. These sound waves generally become less intense
(appear quieter) as they move away from a source, but can reflect back
off of surfaces such as buildings, refract around surfaces such as noise
barriers, be absorbed by surfaces such as grass, and even be focused by
the atmosphere to cause unusually loud or quiet areas. In a community,
the surfaces that can obstruct or redirect sound waves produced by the
various sources of sound in the community are many. Thus, the loudness
perceived by a listener at any one moment will vary greatly depending on
his location. Small movements, even as small as 3 meters (10 feet), can
cause dramatic differences in the level of the community noise. Added
to this complicated spatial variation of noise level is the fact that
the intensity and location of the various noise sources usually change
as time passes (e.g., accelerating motor vehicles). Thus, the fine,
complex spatial patterns of loudness found in the community are con-
tinually changing. For example, during certain periods at a given
location, the noise environment may be dominated by intrusively loud
sounds from specific sources such as automobiles or airplanes. At
other times, it will consist of a constant background of many
indistinguishable sounds.
-------
To measure these spatial and temporal changes of community
noise in detail requires an extremely intense effort. It has been
accomplished only for small areas, such as one city block, in scien-
tific studies in which there were available methods of interpreting
the necessary voluminous data. To assess and describe the "noise
climate" of an entire community, much simpler techniques based on
averages of the noise level fluctuations in time and space must be
used.
3.2 Measures of Community Noise
In community noise work, the subjective loudness experienced
at any instant is measured objectively with a sound level meter as
the instantaneous A-weighted sound level. The term "level" indicates
a measure of what is perceived as loudness, and the term "A-weighted"
indicates that a relative weighting of the sound level at various
pitches that corresponds to the pitch response of human hearing has
been applied. Sound level meters are designed to indicate the A-weighted
sound level in units called decibels, on a meter face as the sound level
changes with time. The decibel scale is a logarithmic scale based on
the pressure of the sound waves, and a unique aspect of the scale is
that almost any sound increasing in level by 10 decibels (dB) will be
judged to have approximately doubled in perceived loudness. Thus, a
passing truck causing a'maximum A-weighted sound level reading of 85 dB
will seem twice as loud to the average listener as a bus at 75 dB.
-------
Likewise, a residence near a highway where continuous traffic causes
a constant A-weighted sound level of 65 dB will seem twice as loud as
one a block or two away where the reading is normally 55 dB.
Since the sound level at any given location within a community
will with time, a way to determine an average level is necessary to
easily describe the total sound environment at that point. One good
measure of the average sound arriving at a point is the equivalent
sound level (Leq - see glossary for technical definition). The
equivalent level of fluctuating environmental noise over a given
period is a single value representing the noise for that period. For
example, the Leq of the 8 minutes of recorded fluctuating noise
shown in Figure 3-1 is 50 dB. The figure also shows short, but loud,
CO
-a
0)
c
o
O)
I
80
70
60
50
40
30
Cor! on Nearby
Boulevard i
Equivalent
Level
Aircraft
Overflight
Locol Cars
[Residual Sound Level
345
Time in Minutes
Figure 3-1. Eight Minute Sample of Typical Fluctuating Sound Level
in Residential Area Showing Maximum, Equivalent, and
Residual Sound Levels for the Period
-------
intrusive sounds such as aircraft or individual cars, and the backgroun<^
ambient sound level, which is the "background" level composed of many
indistinguishable sounds.
To completely assess a community noise environment, the entire
24-hour period must be considered. To describe 24 hours of community
noise at a particular location with a single value, the quantity day-
night sound level (Ldn) has been devised. Ldn is the same as an
equivalent sound level for 24 hours of fluctuating sound, except that
the levels measured during the nighttime hours of 10 PM to 7 AM are
increased by 10 dB to account for increased sensitivity to sounds at
night. One way to estimate the Ldn value for a particular location
would be to take sufficient sound level readings to estimate the equiva-
lent sound level for each hour. The Ldn can then be computed for the
24 hours, including the 10 dB nighttime weighting. Figure 3-2 shows
values of Ldn obtained in various cities using similar procedures and
associates a qualitative description of "noisiness" with Ldn ranges.
An advantage of using the Ldn measure in a community noise evaluation
is that accurate correlations between Ldn value and community reaction
to noise have been widely made for community type sounds. Figure 3-3,
based on several European and American studies, indicates the degree of
annoyance and community reaction that can be expected as the Ldn value
of typical community noise rises.
10
-------
c
or Apartment
~~"_Z_ Boston - Row Housing on Major Avenue
Boise-City Hall in CBD
Watts - 13.0 km from Touch Down at Major
Airport
Newport-J3.6 km from Takeoff at Small |Q||
..Airport
Angeles - Old Residential Area
~I Boise - Single Family Dwelling in Typical
-*t« : .., , Residential Area
Fillmcre - Small Town Cul-'d.e-Sac
D'ego - Wooded Residential
California - Tomato Field on Form
-40
Figure 3-2. Outdoor Day-Night Average Sound Level, L(jn - in
Decibels at Various Locations
11
-------
ANMOYEO
X
o
x.
^-
~Z.
iLt
O
C£
30
20
10
3[
"CLUSTERING SURVEYS"
j ..
ll!
FRE
nd
MUt
PAR
SV.'E
<«" SV/I
LON
FRE
U.S.
O LAX
-iCATHROWA/C (1961) [1/4]
vICH A/C (1966)
HEATr-iKCV.' A.'C (19*7)
-JICH A/C (1969)
IS STREET (1969)
DISH A/C (1972)
SS ROAD (1972)
DON STREET (1972)
SS A/C (1973)
JCH RR (1973)
STREET (1974)
0973)
^^^"
A
' ~b^p;
w^
+ *
"
i
_j
*/'
,/\
/
:
60
70
(decibels )
Figure 3-3. Summary of Annoyance Data from Eleven Surveys that
Show Close Agreement. Two Points from a Recent
Study of Aircraft Noise Annoyance at Los Angeles
International Airport (LAX) [From Reference 2]
12
-------
4 PROGRAM STRUCTURE
The community noise measurement program in Boise was carried out
under management and guidance of the U.S. Environmental Protection
Agency, with field work arranged by the Ada Planning Association. The
program proceeded in four phases: identification of program goals and
study area, selection of measurement sites, field team organization and
field monitoring, and data reduction and analysis.
4.1 Goals and Study Area
As the program's purpose was not only to assess the community
noise climate in Boise, but also to evaluate various survey and analysis
techniques for general application in community noise surveys, more data
collection and manipulation was performed than is ordinarily necessary
for a community noise study. The study area therefore included almost
all the land area within the city limits. Some areas to the west were
neglected due to lack of development and similarity to other included
areas, but the survey boundary was extended beyond city limits in areas
of new developments or possible annexation which were of interest to
planners.
4.2 Measurement Site Selection
Two basic types of sites were devised to survey noise over the
wide ranges of land use and noise exposures in the city. These sites
were supplemented with special sites providing supplementary supportive
data.
13
-------
Basic Sites
Two types of sites provided the basic project data - interior
sites representative of the community in general, and roadway sites
representative of the environment along major streets. The interior
sites were arranged according to a north-south grid pattern with 540 m
(1/3 mile) grid spacing. This pattern produced 266 square cells 540 m
(1/3 mile) on a side covering the entire study area with the measure-
ment point selected as close to the cell center as possible. Sound
level measurements were taken at all of these sites. Roadway sites
were located adjacent to surface streets and limited access highways.
40 sites were selected along high volume (ADT>18,000) medium volume
(18,000>ADT>6000) and low volume (ADT<6000) roads to assess the noise
environment with useful accuracy. (See Appendix A for sample size
rationale).
Supplementary Sites
Two additional types of sites were used to provide supplementary
data: 24-hour sites and quiet period sites. 10 sites for placement
of 24-hour monitoring equipment were selected throughout the city to
obtain a record of hourly sound level variation. These sites were
generally located at homes of people associated with the project for
convenience. Quiet period sites throughout the area were visited
between 1:30 and 5:30 a.m. on a typical night to quickly spotcheck
minimum noise levels during the quietest hours. Approximately half
14
-------
of these sites were co-incident with interior, roadway, or 24-hour
me a s u r erne n t sites.
4.3 Noise Measurement Methods--*
Principal data for the study were obtained from the basic sites
located on the 1/3 mile (540 m) grid or along roadways. All measurements
made at these sites employed the same procedure. Different procedures
were used at the 24-hour and quiet-period sites.
Basic Sites 20-Minute Measurement
At each interior or roadway site, sound level readings were
continuously made for a 20-minute period sometime between the hours
of 9 AM and 5 PM during weekdays. Monitoring assignments were selected
for efficient personnel usage, and this resulted in the measurements
being uniformly distributed throughout most times of the day. A total
of 10 days were spent with one to three measurement teams in the field
each day.
For each 20-minute measurement period, the A-weighted sound
pressure level was monitored using an ANSI Type II sound level meter
set for slow meter response. Every 15 seconds, the instantaneous meter
reading was observed and the value recorded as a tick mark in a space
for the appropriate level on a standard data sheet. In this way,
approximately 80 sound level values were recorded during the 20 minutes
at each site for subsequent computer reduction. At each of the 15
15
-------
second intervals, any sound level meter readings from local sources
which caused the reading to exceed 70 dB were described on the data
sheet by a special notational code which identified the source.
Field personnel consisted of Ada County Planning Association
employees, local college students studying environmental sciences,
and volunteer high school students. All participants were given
thorough instruction and demonstration regarding these specific sound
measurement procedures. Field teams of two were organized at first
to facilitate timing, reading and recording, but with a day's practice,
a single person could easily manage the technique.
Special Sites
Twenty-four-hour measurements were made using a community noise
analyzer which automatically determined the equivalent sound level for
each hour. EPA personnel set up this equipment which was self-operating
for the measurement period.
The quiet period nighttime measurements were made by a trained
acoustics technician using an ANSI Type I sound level meter having
a minimum reading ability of 30 dB. With the meter set for slow
response, it was observed for 30 seconds and the estimated central
tendency of the meter reading was recorded. Care was taken to exclude
the effects of local events such as automobile passbys or dogs barking.
16
-------
4.4 Data Reduction
The data from each of 307 20-minute measurements consisted of
approximately 80 individual sound level meter readings. Primary reduc-
tion of these data was done by the Boise Center for Urban Research
a group affiliated with Boise State University using a FORTRAN IV
program to calculate Leq and other measures for each site based upon
the 80 readings for each 20-minute measurement. The Leq values for
interior sites were then divided according to five types of land use.
This yielded a set of Leq values from sites representing each of the
five land use categories plus low, medium, and high volume roads. The
mean for each set of Leq values was hand-calculated resulting in an
average daytime Leq for the following types of areas:
53.7 dB Residential
62.9 dB Commercial
Land Use
54.2 dB Industrial
Catagories
65.4 dB Airport Influence NET 40 Zone
57.7 dB Airport Influence NET 30-40 Zone
52.5 dB Parks, Open or Undeveloped Space
65.9 dB High Volume Roads
64.0 dB Medium Volume Roads Road Traffic Volume
54.2 dB Low Volume Roads
An approximate conversion from average daytime Leq to L<}n, which
represents the 24-hour noise environment, was developed based on the
24-hour data. (The Leq to L^n conversion is described in Appendix B.)
17
-------
This conversion was then applied to the average Leq values to.determine
L^n for each land use area. The resulting values are presented in
Section 5.
An advantage of the on-the-spot sound level meter technique
is that the field teams are able to note those local sources which are
loudest or occur most frequently. The identifiable sources causing the
regular sound level measurement to exceed 70 dB were counted in a special
portion of the data sheet and the raw data were manually tabulated to
determine the relative frequency with which the various noise sources
caused the measurement to exceed 70 dB. These results are also shown in
Section 5.
The 24-hour data were directly transcribed from the community
noise analyzer to tables and then to 24-hour charts which are included
in Appendix E. The data for the quiet nighttime levels were manually
recorded average values of the A-weighted sound level as observed for
30 seconds and required no reduction.
18
-------
5 RESULTS AND RECOMMENDATIONS
5.1 Results and Conclusions
Shown in Figure 5-1 are the average L(jn values for various land
use categories that were within the survey boundaries. Comparison of
these average levels with the interpretive scale which was shown on
Figure 2 in Section 3 reveals that the average Day-Night Sound Level for
residential areas is considerably lower than one might expect for a city
of Boise's size, where many residential areas closely adjoin commercial
areas or busy streets. However, it is also evident that noise in the
industrial, commercial, and central business districts has crept to the
same disturbing levels encountered in many urban areas.
Industrial and Commercial Areas
It is apparent that in Boise, the principal noise source outside
of the airport influence area is street traffic. The average L^n value
for roadway measurement sites selected along roads having an average
daily traffic (ADT) volume greater than 6,000 vehicles per day corresponds
quite closely to the L^n from interior sites located in commercial or
industrial areas. This indicates that vehicle traffic probably accounts
for the high sound levels measured in these areas, and that traffic volume
increases can be expected to increase the average L^ accordingly.
19
-------
Table 5-1. Average Sound Levels for Area Types Surveyed With
20 Minute Interior Measurements
Land Use Category
Central Business District
Commercial/ Indus trial
Residential
Parks /Unused /Open
Adjacent to Roads
> 6000 ADT
Adjacent to Arterials
< 6000 ADT
NEF 40 Zone
NEF 30-40 Zone
No. of
Sites
5
37
170
24
35
6
13
17
Mean
Day-Night Average
Sound Level (L^)* in dB
66
62-63
54
53
63-66
54
66
58
95%
Confidence
Limits, dB
>+5
+4.5
+1.5
±5-5
±3-5
+5.5
>+5.5
+4.5
*Approximately value from 20 mm measurements during day,
20
-------
Central Business District
The average L^n for the central business district (CBD) shown in
Table 5-1 has a value as high or higher than that of any other land use.
Figure 5-2 shows the hourly equivalent sound levels of a 24-hour measure-
ment made at City Hall in the heart of the CBD. Observation of the area
indicates the primary sources to be traffic and construction noise. The
continuous nature of these two sources during the day is indicated by the
regularity of the Leq line. This is particularly true during late morning
and afternoon where high Leq levels are consistently maintained, indicat-
ing a continuous high volume of traffic flow. Even after this period and
into the middle of the night, the hourly Leq decreases only 13 dB . This
is a much smaller decrease than normally occurs for other land use areas
in Boise (as will be seen), and indicates a concentration of traffic in
the CBD at all hours.
Residential Areas
The average L^n value for roads with an ADT of less than 6,000
vehicles per day is the same as that for residential interior sites. This
indicates that on the average, local traffic sound levels along residential
streets equal those generally prevailing in residential areas. Thus, any
increase in local traffic volume would be expected to immediately cause
increases in the average residential sound level. The difference in average
L,dn values between residential and industrial/commercial areas of almost
10 dB indicates that residential areas are not yet extensively crossed by
21
-------
Summary of sound levels at
City Hall - January 10, 1977
Day-Niight Average Level
(Ldn): 65.7 dB
HOURLY INFORMATION
CO
o
W
>
w
§
M
5:30 to 7: 30 a.m. not shown because of
instrumentation failure.
Figure 5-2. Hourly Sound Levels at Boise City Hall
-------
roads of ADT greater than 6,000. This is a situation which should be
preserved to prevent imposition into residential areas of the much greater
sound levels measured for roads with ADT over 6,000. Figure 3-3 indicates
that such imposition could instigate significant community action. Figure
5~3 shows the general trend of sound level data taken along roadways in
Boise as compared with ADT, and illustrates how the sound level of a
residential area might increase as it becomes criss-crossed with roads
of ADT greater than 6,000.
A further correspondence between current residential L(jn and the
L(jn of roads carrying an ADT under 6,000 is revealed by the 24-hour data.
Figure 5-4 is a plot of hourly Leq values measured in a residential area
near the open foothills of the eastern city limits. (See Appendix F for
a complete set of the residential 24-hour data taken.) Figure 5-5 is a
similar plot of data taken at a site along a wide surface boulevard lead-
ing through the older residential north section to newer subdivided sec-
tions of the city which are expanding into the foothills to the northeast.
The boulevard - having an ADT under 6,000 - shows low sound levels late
at night, beginning to rise at 6AM with a morning peak, and rising again
to a fairly constant level which tapers off during the evening to the low
nighttime levels. The residential pattern of Figure 5-4 is similar with
the noticeable exception of pronounced peaks around 5 and 7PM. It is
likely that these peaks correspond to returning home and evening traffic,
and thus the importance of vehicle noise to the residential noise climate
23
-------
00
T3
CD
a
c
3
O
oo
CD
O5
(0
CD
>-
ro
Q
80
7G 4-
60 4,
40
0
X
Mean of 6 Sites
ADT < 6000
i i
i Range of Data
Mean of 23 Sites
6000 18000
24000
Figure 5-3; Sound Levels Adjacent to Major Roadways in Boise
-------
pa
o
w
>
9
Q
55
D
O
CO
HOURLY INFORMATION
Day-Night Average Level
(Ldn): dB
40
30
12
NOON
24
MIDNIGHT
TIME OF DAY
Figure 5-4.
Hourly Noise Levels in a Typical Residential Site
Near Open Foothills Near Eastern City Limits of Boise
-------
ffl
O
w
a
Q
D
O
50
40
HOURLY INFORMATION
DAY-NIGHT AVERAGE LEVEL
(Ldn): 56.5 dB
30
12
NOON
24
MIDNIGHT
TIME OF DAY
Figure 5-5. Hourly Noise Levels Along a Major Arterial Through
Residential Areas in Northern Area of Boise
-------
is demonstrated. Changes in the sound levels or use-patterns of motor
vehicles will immediately and directly affect residential sound levels.
Parks and Open Space
For simplicity, all open space, including parks, undeveloped land,
and agricultural land has been considered as a single land use category.
As indicated in Table 5-1, the average L(jn for all these areas is low,
but not extremely so for a city like Boise. In actual fact, the sound
levels measured throughout these areas were widely distributed between
extremely quiet and excessively loud areas. Thus, the sound level at
each individual section of open space reflects the levels of surrounding
sources or land use. On the average, the levels are just slightly higher
than those for residential areas.
Airport Influence Area
Several of the regularly spaced interior measurement sites were
located within the airport influence area to the north and west of the
runways. Since measurements among these sites were made during several
different days, allowing for several different flight patterns, it is
assumed that the resulting data approximately represent the airport
influence area.
Figure 5-1 shows the area within the present Noise Exposure Fore-
Cast (NEF) 40 contour* to have a high average L^n similar to commercial
*NEF contours were previously developed in the report "Boise Airport
Influence Area Study" for the Ada County Council of Governments.
27
-------
and industrial areas. The nature of the noise is quite different, how-
ever, in that it consists of periodic loud but short duration overflights
occurring in an otherwise quiet region. Figure 5-6 illustrates this with
hourly Leq values for a 24-hour period measured near the edge of the
NEF 40 zone off the west end of the runways. The Leq line, which is an
indicator of the total acoustical energy received each hour, is quite
high indicating the presence of high noise level sources. The L^Q line,
which indicates the sound level which was exceeded only 10 percent of the
time during each hour, is far below the Leq line. Thus, the sources which
presented the large amounts of sound energy (aircraft) were present much
less than 10 percent of the time. A similar but less dramatic pattern
would be expected in the zone between the NEF 40 and NEF 30 contours
(NEF-30 zone), where a lower average L
-------
Day-Night Average Level
P3
o
w
>
w
j
Q
HOURLY INFORMATION
40
30
12
NOON
24
MIDNIGHT
TIME OF DAY
Figure 5-6. Residential Area Impacted by Airport Noise
-------
the NEF 30-40 zone, the average L^n i-s significantly higher than that
for other residential areas. In this zone, indoor environments would
be marginally acceptable for residential use but with attention to con-
struction details (such as proper fitting and sealing of wall panels,
windows, and other building elements), would be nearly equal to those
of residences in other areas. The outdoor environment, however, would
be noticeably less desirable. This indicates a possibility for housing,
such as planned unit developments or condominiums which do not feature
the private yards and local outdoor living opportunities of the single-
family residences found in most of Boise. The introduction of streets
with ADT greater than 6000 to the NEF 30-40 zone would increase the
local L^n and also the residual sound level between overflights.
Major Sources
Figure 5-7 shows the relative numbers of various sources which
could be identified as causing the A-weighted sound level to exceed
70 dB during most of the 20 minute measurements. The figure is for
the entire study area, excluding the airport influence zone, and
indicates - not unexpectedly - that autos and trucks most frequently
cause high local sound levels. A more detailed examination of
vehicle sound levels is presented in Figure 5-8. This shows that
the apparent A-weighted sound levels of automobiles throughout the
community are closely grouped, with few cars being much noisier
than the bulk. Thus, a noise regulation or enforcement program
30
-------
640 Readings of A-Weighted Sound Level from
70dBto80dB
Off Road
Vehicles 0.6%
Motorcycles 0.4%
Buses 1.3%''
Railroads 0.5%
Construction Eqpt 2.5%
Small Planes 1.2%
Helicopters 1.1%
42 Readings of A-Weighted Sound Level Over 80 dB
Automobiles 11.9%
Jets 9.5%
Pff Road Vehicles 2.4%
Motorcycles 2.4%
Buses 4.8%
Emergency Vehicles 2.4%
Construction Eqpt. 19%
Figure 5-7. Sources of Intrusive Single Event Noise Levels
in Boise Excluding Airport Influence Area
31
-------
250
200
208
164
CD
0)
150
o> 100
E
50 --
100
31
15
70
72 74 76 78 80 82 '84_ 86 88
A^Weighted Sound Level in 2 dB Increments
90
92 94 96 98, TOO
Figure 5-8. Distribution of Automobile Sound Levels Above 70 dB
Measured at Various Community Locations in Boise
for cars would probably not cause a significant reduction in automobile
traffic noise levels unless virtually all of the cars were made quieter.
However, as illustrated in Figure 5-9, one to two percent of the trucks
with measured sound levels exceeding 70 dB were significantly noisier
than the majority. This suggests that a noise enforcement program for
trucks to insure adequate muffling and reasonable operation within city
limits could result in a noticeable reduction in truck traffic sound
levels along truck routes. Figure 5-10 shows that in the airport influ-
ence area, jet aircraft join trucks and autos as a frequent source of
high sound levels. It is interesting that even at very high levels
over 80 dB, trucks constitute nearly as many intrusions as aircraft.
32
-------
Number of Trucks Measured
§ g
i > i i i i i i
»
*
44
36
'96
34
37
4 14 i '3 .3 2 13
i i 1-, 1 1 1 * H 1 1 n f
70i 72 74 76 78 80 82 84 86 88 90 92 94 96 98 10(
A-Weighted Sound Level in 2 dB Increments
Figure 5-9. Distribution of Truck Sound Levels Above 70 dB
Measured at Various Community Locations in Boise
This implies that the airport area average sound levels may be more
sensitive to increased truck traffic than indicated in Section 5.1.5,
5.2 Recommendations
The natural silence of the Boise Valley has not been completely
eliminated within Boise city limits by modern activities. Late at night,'
when the movement of people is at a minimum, the extremely low A-weighted
sound levels shown in Table 5-2 were measured. Such low levels, averag-
ing 37 dB, are never achieved in many metropolitan areas, and serve to
illustrate the real opportunity that the City of Boise has to preserve
its peaceful environment. T"he following recommendations, based on the
sound survey, will help area planners prevent the increase of sound
levels throughout the city.
33
-------
131 Readings of A-Weighted Sound Level
from 70dB to 80dP
Automobiles
38.9%
Helicopters
8.4%
43 Readings of A-Weighted Sound Level Over 80 dB
Helicopters 4.7%
Construction Eqpt.
9.3%
Figure 5-10. Sources of Intrusive Noise in the
Boise Airport Influence Area
34
-------
Table 5-2
Minimum Sound Levels Found in Boise
Time
0135
0155
0200
0216
0219
0227
0233
0241
024i
0251
0305
0308
0315
0324
AOOC
0347
0355
0404
0412
0419
0425
0439
0445
0458
0509
0520
0525
0534
0549
Site Also Used
As
24-Hour Site
X
X
X
X
V
X
X
Site Address
Elmer & Eugene
Hill Road
2715 28th Street
Clover & Moore
501 Rose Street
Harrison
Highland View and Heather Place
8th Street
Franklin i llth Strcef
1050 Kroll Street
529 Bacon
207 Louisa
City Hall (No. Side)
1916 Larch
2SCO F.-y*
9801 Skycliffe
Edna & Oalton
2951 Dolton Ln
Preece at Dead End
7111 McMullen
6603 Holiday Drive
Victory & Eagleson
4256 Banner Street
Nei Pierce & Toggart
217 Redfish Lane
2801 Harmony Road
Boise i Holcomb Road
1308 Euclid
Julia Davis Park
Average
A- Weighted Sound Level
for 30 Seconds, dB
38
39
35
39
37
42
34
34
39
39
30
33
51
33
*i**
32
37
34
36
38
41
44
38
36
44
31
36
39
40
Land Use
Residential
Residential
Residential
Park, Open Space
Residential
Residential
Reiidential
Residential
School, Open Space
Residential
Residential
Residential
CBD
Reiidential
Reiidf.iiol
Residential
Reiidential
Vacant
Agricultural
Residential
Residential
Vacant
Residential
Residential
Residential
Agricultural
Agricultural
Residential
Park, Open Space
Mean = 37.3 dB
St. Deviation = 4.5 dB
35
-------
Industrial and Commercial Areas
Since average sound levels in these areas result principally from
road traffic, the growth of traffic volume should be limited to those
roads bounded by compatible land use zones. This is particularly important
for commercial areas where greater volume will readily increase sound
levels to which the public is exposed during routine nonoccupational
activities. In some cases, it may be desirable to direct traffic to sev-
eral streets at lower volumes rather than a few principal streets at
high volumes.
Residential Areas
Average sound levels in residential areas are also closely tied to
road traffic and thus traffic volume along local and collector streets
should not be allowed to grow markedly. The use of arterials through
residential sections intended to carry high traffic volumes O6000
vehicles per day) should be discouraged, or coupled with provisions
for compatible land use or buffer zones (or sound barriers) along the
road.
Parks
In order for park areas to provide visitors the tranquility of
the quiet natural environment of Boise, they should not be located adja-
cent to commercial or industrial areas, or roads with ADT approaching
6,000.
36
-------
Airport Influence Area
The area within the NEF 40 contour is presently compatible with
nonresidential activities such as most industry; agriculture, or range-
land use. Traffic growth, including heavy trucks to supply industry,
will increase average sound levels by a small amount. The NEF 30-40
zone is suitable for the same activities as the NEF 40, and also com-
mercial and/or shopping areas. Growth in surface traffic volume - espe-
cially to the 6,000 vehicle per day level - will noticeably increase
average sound levels. If residential development is contemplated for
areas within the projected 1992 NEF 30-40 zone construction should
provide a noise reduction of A-weighted noise levels at least 5 dB
greater than that of typical construction in other areas to assure a
comparable interior environment. It would also be desirable to arrange
the housing so as to minimize the need for outdoor activities; for
example, by providing covered communal recreation areas.
Major Sources
To remove some of the most intrusive roadway sounds, a vehicle
noise enforcement program could be instituted to reduce the sound
levels produced by heavy trucks. An enforced requirement that the A-
weighted sound level of a vehicle not exceed 86 dB at 50 feet when
operated on a surface street would be consistent with regulations in
effect in other cities and states, and would result in a reduction in
sound level of approximately the loudest 2 percent of trucks operating
in the city.
37
-------
REFERENCES
1. Impact Characterization of Noise Including Implications of Identify-
ing and Achieving Levels of Cumulative Noise Exposure, Henning von
Gierke, Task Group Chairman, U.S. Environmental Protection Agency,
July 27, 1973.
2. Schultz, T.J., et al "Recommendations for Changes in HUD's Noise
Policy & Standards, Appendix B - Social Surveys on Noise Annoyance -
A Synthesis" Bolt, Beranek and Newman Report for U.S. Housing and
Urban Development, Report No. 3119R, November 1976.
3. Wyle Research "Community Noise Monitoring - A Manual for Implemen-
^
tation" for U.S. Environmental Protection Agency, Report WR 76-8,
July 1976.
39
-------
A-Weighted Sound
Level
Day-Night Sound
Level (Ldn)
Decibel (dB)
GLOSSARY
A sound level determined using the "A" fre-
quency weighting of a sound level meter which
selectively discriminates against high and low
frequencies to approximate the auditory sensi-
tivity of human hearing at moderate sound levels.
Measures such as L^n and Leq , which are devel-
oped in terms of A-Weighted sound levels, have
been widely correlated with degrees of community
noise impact and annoyance.
is a calculated single number which describes
environmental noise for 24 hours based on the aver-
age energy content. It is often calculated by
averaging the energy content of all hourly Leq's.
(See equivalent sound level.) To account for
increased nighttime sensitivity to noise, the Leq
values for the nighttime hours (2200 to 0700) are
increased by 10 dB for the calculation.
A unit for describing the amplitude or level of
acoustical quantities - see Level.
41
-------
Equivalent Sound
Level (Leq)
Frequency
Level
A measure which describes the sound level of a
time period of fluctuating environmental noise
with a single number. Leq is an average level
based on the average energy content of the sound
rather than average sound level. It is the con-
stant sound level which would contain the same
amount of acoustical energy as the fluctuating
level for the given period. When reporting Leq
values, the time period over which the noise is
averaged must be specified; for example, for
measurements taken over an 8 hour period, the
equivalent sound level is expressed Leq(8).
These measurements, and the resulting Leq
values, are A-Weighted, unless specifically
designated otherwise.
The number of sound pressure fluctuations per
second of a particular sound expressed in hertz
(cycles per second). Frequency is the property
of sound that is perceived as pitch.
A scale for describing the amplitude of acoustical
quantities. In environmental acoustics, usually
ten times the logarithm (base 10) of the ratio of
an acoustical quantity which is proportional to
power (i.e., sound power; sound pressure squared,
42
-------
Background Ambient
Sound Level
Sound Level
Statistical Sound
Level (L )
x
sound intensity, etc.) to a reference quantity of
the same kind. The value is assigned the unit
decibels.
The sound level which exists' in the absence of
any local identifiable sound sources. Usually
perceived as a background rushing sound of many
indistinguishable sources.
The instantaneous sound pressure level in deci-
2 2
bels defined as Lp = 10 log (p /p ) where p is
the acoustic pressure and p is 20 micro-
pascals. In practice, this quantity is measured
in decibels directly with a sound level meter,
usually applying the A-weighting network of the
meter (see A-weighted sound level).
The sound level which is exceeded for a particu-
lar percentage of the time during a given period.
The percentage of time exceeded corresponds to the
subscript for each metric. For example, the L_
of a period of environmental noise is a low level
exceeded 90 percent of the time, but the L is a
higher level which was exceeded only 10 percent of
the t ime.
43
-------
APPENDIX A
SURVEY METHOD
PLANNING
From the point of view of deriving information, the survey
was classified into two types of sites those representative of the
community in general and those representative of highway impact. From
the planning perspective, it was necessary to develop two separate site
selection techniques to characterize these different types of sites.
To characterize the community in general, the city and sur-
rounding areas were divided into 54 1.6 km (1-mile) square sections each
corresponding to an official section as used in the standard surveying
scheme. The survey boundary did not include all of the 54 sections.
Using section maps having a scale of one inch to 200 feet, each section
was divided into a threeby^three matrix thus producing nine cells of
equal area. In residential areas, the closest street to the centroid
of each cell was located and the measurement site located at the edge
closest to the centroid. The actual measurement point was located by
applying one of two criteria. If a building was located at the site,
the measurement point was located 2 meters (6 feet) in front of the
building and 2 meters (6 feet) from the edge opposite the driveway as
shown in Appendix D attached. If there were no building located
at the site, then the measurement point was located 15 meters (50
feet) back from the curb.
A-l
-------
Initially all cells (originally 360) within the survey bound-
aries were to be measured. Owing to resource limitations, the size of
the survey was reduced in area such that only 266 were measured.
The method for selecting sites along roads having medium
traffic (i.e., the average daily traffic (ADT) flow is between 6,000
and 18,000 vehicles) and for roads having high traffic (i.e., the ADT
was greater than 18,000 vehicles) as follows.
First, for each road category (i.e., medium and heavy
traffic), potential sites were located along each road at approximately
13 km (12 mile) intervals. For medium traffic roads, 222 potential sites
were identified. For high traffic roads, 50 potential sites were identi-
fied. Assuming standard deviations of sound levels along the medium and
high traffic roads of 5 and 3 dB respectively, the required sample sizes
were determined by referring to Figure A-l. Thus, to be able to gener-
ate mean sound level values with 95 percent confidence that they are
correct within +2 dB, medium traffi'c and high traffic samples of 27 and
11 measurement locations would be required respectively. Again, due to
resource limitations, different sample sizes were actually obtained and
the standard deviations of the measured data were slightly different
than assumed. Actual sample sizes are given in Appendix B. Owing to
particular concern for low volume streets, additional measurement loca-
tions adjacent to various local streets (ADT <6,000) were also selected.
A-2
-------
95%
Confidence
Limits,
dB
. Standard Deviation of Sample, dB
Figure A-l. Required Sample Size for Various 95 Percent
Confidence Limits On Population Standard
Deviation
A-3
-------
The actual microphone locations for road measurements were
obtained moving 2 meters (6 feet) in front of any building located on
the site or 30.5 meters (100 feet) away from the curb for high traffic
roads, or 15.2 meters (50 feet) away from the curb for medium traffic
roads.
TEMPORAL METHODS
The survey utilized two temporal techniques: manual 20-
minute samples and automatic 24-hour samples. The former technique was
utilized to generate statistical data and derive the Leq's for a
20-minute non-peak traffic period. It required the collection of data
by personnel (either APA, EPA or City staff, Boise State University
students or Borah High School students) who at each site measured the
A-weighted sound level using an ANSI Type II sound level meter set to
slow response. At the end of every 15-second interval, the instanta-
neous meter reading was'recorded. For levels less than 70 dB, the
level was tallied by placing slashed lines corresponding to each
occurrence in the appropriate 2 dB-wide sound level band on the data
sheet (see Appendix D). Above 70 dB, source codes rather than slashed
lines enabled a means of source identification. Thus each observer
constructed a distribution of the sound levels, indicated the sources
of all events over 70 dB, and noted general comments on road condi-
tions, source environment, and any other pertinent input.
A-4
-------
Three Metrosonics dB 602 Community Noise Analyzers automati-
cally collected the 24-hour data. The units were located at 10 locations
throughout the city. To provide equipment security and AC power, the
measurement locations were flexible; however, all locations were visually
unobstructed from the street. The community noise analyzers were set to
collect the following information on an hourly basis Leq>
and
ANALYSIS
The 20*minute samples were coded onto computer cards and
processed using the computer program listed in Appendix B. The 24-hour
hourly data were directly read from the community noise analyzers. L(jn
was calculated by a separate computer program from the hourly Leq values.
A-5
-------
APPENDIX B
DATA REDUCTION AND ANALYSIS
This appendix provides supplementary and background material to
sections 4.4 and 5.0 of the report. Data handling or analysis details
not fully covered in those sections are presented here.
Data Reduction
Approximately 24,560 individual sound level readings were made
during the 20-minute measurements throughout interior areas or along
roads. These readings were reduced by computer to a few useful average
values. For each 20-minute measurement, the computer produced one page
of information including:
o Equivalent sound level (Leq) for the 20-minute measurement
period.
o Sound level distribution of sources exceeding 70 dB
o Time of day of the measurement
o Land use of the measurement area
o Exact measurement location coordinates.
An example reduced data page is shown in Figure B-l. The computer
program which was used is included at the end of this appendix.
Using the land use or site codes of the printed output, the data
were separated into the area categories shown in Table B-l, each cate-
gory containing the indicated number of 20 minute samples. In each
category- the numerical means of the L^Q and Leq values for the
B-l
-------
IE
,ER I
DO
UTC
M
-HOI
l-rtts
S, . U33- _ ,1 SI J)N a UE ' "1.
«»»«*»***««*««*+««*«*«******«
*»«»****«*»**********«*****»*«*»********«**»<<»*****«**»"r
SITE = 125 YARDS FROM FREEWAY
DATE » JAN 11 1977 SHEETS =» 1
**»***«*«*««»*«*»***«**»«*****»*««**»****»******»****«****«**»*.»«*«*************************«***»*
HOUPLY INFORMATION
125 YARDS'FROM FREEWAY
JAN 11 1977
IMPACT "FREEWAY TRAFFIC
GENERAL COMMENTS =BARKING DOGS-CHAINSAW-FREEWAY NOISE
HOUR » 11.48-12.09
EATHER: CONDITIONS =F TEMPERATURE « -6. c .WIND SPEED
DB
0- 2
2- 4
4- 6
6- B
8- 1O
10- 12
12- 14
14- 16
16- 18
19- 20
20- 22
22- 24
24- 26
26- 28
23- 30
33- 32
32- 34
34- 36
36- 33
31- 40
4O- 42
42- 44
44- 46
,_, 4a- 48
V 43- 50
M 50- 52
52- 54
54- 56
5o- S3
S3- 60
60- 62
62- 64
64- 66
66- 69
69- 70
73- 72
72- 74
74- 76
76- 78
78- 80
SO- 82
82- 34
84- 66
&f>- B9
«»3- 90
90- 92
92- 94
94- 96
96- 93
99- 100
S. (KTS)
TOTAL NUMBER OF SAMPLES
NUM3ER
0
0
0
0
O
0
0
0
0
0
O
0
0
0
0
0
0
0
0
O
11
7
20
4
10
4
6
7
2
2
1
O
1
0
O
1
0
0
0
0
0
0
0
0
0
0
0
0
0
OF OCCURRENCES
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
81
LMAX = 73
L.I = 73
LI = 73
L10 = 57
LSO = 47
-tO = 41
L9
-------
Table B-l
Summary of 20-Minute Measurements
Taken Between 9:00 AM and 5:00 PM in Boise
w
u>
Type of Site
Residential
Commercial
Roads < 6000 ADT
Roads > 18000 ADT
Roads 6000+ 5
+ 5.5
+ 4.5
>+ 5.5
-------
20 minute samples were calculated, along with the standard deviation
of the Leq values. These are also tabulated in Table B-l and were
the principal reduced data used for analysis.
Data Uncertainty
The survey technique used in Boise contains two principal types
of data uncertainty - sampling error and measurement error.
Sampling Error
In each land use area, a finite number of 20 minute samples was
taken to estimate the mean Leq for the area. The sample size (number of
20 minute Leq values) necessary to estimate the actual area mean Leq to
within ascertain confidence interval with a specified confidence is
related to the standard deviation of the population of all possible
20 minute Leq samples. In order to be sure, with a specified degree
of confidence, that a sample estimate of population mean falls within
a given confidence interval, j^A> it is appropriate to apply the equation:
A = to-
where: t = the confidence parameter (from a student's "t" distribution)
which depends upon the degree of confidence desired in the sample and
on the sample size
cr = the standard deviation of the population of all possible
samples (in this case, 'of all possible 20 minute Leq values) and
n = the sample size.
A graph of this equation is shown in Figure B-2 .
B-4
-------
95%
Confidence
Limits,
dB
>-r ( I i t
: 9 .: 10 :: 11
Figure B-2. Sample Size Needed to Measure a Population
Mean with 95 Percent Confidence
B-5
-------
This figure was used as explained in Appendix A, to estimate desired
sample sizes for the land use area categories based on a standard devia-
tion estimate for each category. These desired sizes were not always
reached, however, due to logistical and manpower difficulities. Thus it
was necessary to determine the confidence intervals for the sample sizes
which were achieved. These were obtained from Figure B-2 using the stand-
ard deviation of the sample as an estimate of that of the entire popula-
tion. These estimated confidence intervals for a 95 percent confidence
level are given in Table B-l for each land use area category.
Measurement Error
The 20 minute measurements were performed by manually reading a
sound level meter at 15-second intervals. Uncertainty in these readings
is provoked by calibration accuracy, meter accuracy; and reading accuracy.
Although all field personnel were trained in the use of electronic sound
level meter calibrators, insufficient calibrators were on hand for assign-
ment to every field team. Thus, some teams were unable to check calibra-
tion at regular intervals throughout a day of measurements. For these
teams, the meter was calibrated at the beginning of the day, and this
calibration was checked upon the team's return. In general, these
beginning and end checks indicated the meters to have maintained calib-
ration within 1 dB even with the varying low outdoor temperatures. This
may have been partially due to the consistent use of fresh batteries.
Meter and reading accuracies can be considered together. The accuracy of
B-6
-------
a Type II sound level meter required by ANSI Standard SI.4 - 1971 when
indicating A-weighted levels of community noise is no worse than plus or
minus 1 dB. Also, since instantaneous "snapshot" type readings were
often required while the meter needle was moving (slow meter damping),
it is judged that reading accuracy was no better than plus or minus 1
dB. For both meter and reading accuracies, however, there is no reason
to expect that the errors would be biased toward the plus or minus side,
since several different combinations of meters and observers were used.
Thus no significant fixed error would have been induced into either the
calculated Leq for each 20 minute sample or the calculated mean Leq for a
group of samples representing a land use category.
Uncertainty Summary
The confidence with which the mean values of the measured samples
represent the true community noise level mean values was determined
using Figure B-2 and is expressed in Table B-l. Uncertainty of the
measured samples due to sound level meter calibration was seen to be
insignificant. Measurement errors due to instrument or reading errors
are presumed to be randomly distributed about the equivalent or mean
values, and therefore will not significantly alter the calculated
equivalent sound levels or their means. Hence, measurement uncertainties
do not degrade the confidence intervals and levels established by the
i
sample sizes selected.
B-7
-------
Table B-l shows that the mean Leq values determined for almost
all areas of the survey are within 5 dB of the actual population means
with 95-percent confidence. In particular, the mean noise levels in
the important residential and medium to high volume road areas have
been determined with an especially narrow confidence interval. Thus,
the confidence in principal data is sufficient to allow the conclusive
interpretations of Section 5.0 of the report.
Leq(8) to ^dn Conversion
The principal survey data for each site consisted of the Leq for
a 20-minute period between the weekday hours of 9:00 AM and 5:00 PM.
Each land use area within the city contained several such sites, and
their 20 minute samples were uniformly distributed throughout the 9:00
to 5:00 period. Thus, for each land use area, the 20 minute Leq values
could be arithmetically averaged to estimate, with a certain confidence,
the average Leq in the area for the 9:00 to 5:00 period. (The con-
fidence in the average Leq(g) estimation is developed elsewhere in this
appendix.) A method was then developed to determine the average L,jn for
each land use area based on this average Leq(8).
The method for determining the Lgq-to-L^n conversion was derived
from the 24-hour sound level measurements, which gave hourly Leq values
for several locations around the city. From these values the L^n and
the Leq(g) from 9:00 to 5:00 were calculated for each site. This allowed
a direct and accurate comparison of the 9:00 to 5:00 Leq with the Ldn
B-8
-------
for these sites. The 24-hour results were then separated according to
land use, yielding an assessment of the difference between 9:00 to 5:00
Leq and L^n for each type of area. These differences are shown in the
fourth column of Table B-2, where it can be seen that, on the average,
the magnitude of this difference is always much less than 1 dB.
It was then assumed that the differences between the average Leq(s)
and L
-------
Table B-2
Differences Between Leq(s) (9:00 AM 5:00 PM) and Ldn
Calculated from Weekday 24-Hour Measurements in Boise
Land Use
(24-hour
measurements)
(24-hour
measurements)
- Leq(8).dB
(24-hour
measurements)
Average Leq(8),dB
(20-minute
measurements)
Residential
Averages:
Airport Influence
59.3
45.4
51.5
51.7
54.7
60.4
57.1
43.4
53.6
53.2
54.3
52.3
60.9
2.2
2.6
-2.1
-1.5
0.4
0.32
-0.5
53.7
Arterial
<6000 ADT
Averages :
56.5
58.0
59.6
"
55.5
59.7
60.7
58.6
1.0
-1.7
-1.1
-0.6
54.2
58.2 to 65.9
CBD
65.7
65.3
0.4
66.4
B-10
-------
would cause the calculated Ldn value to just equal the daytime Leq as
is the case on the average for Boise's quiet areas. The previous study
also showed that, as L^ increased from 55 to 65 dB, the difference between
daytime and nighttime Leq would decrease to 4 dB, which would permit the
nighttime values to dominate the L^n calculation (when the 10 dB weight-
ing is added) and cause the L^ to exceed the daytime Leq. It is
apparent that in Boise this does not happen. In areas of Boise with a
high L(jn, the nighttime levels apparently are not great enough to increase
the L(jn, but remain at a level sufficiently low to keep L^n approximately
equal to daytime Leq.
It is concluded that the approximate difference between the daytime
average Leq determined by the 20-minute surveys and L^n at the same
site in Boise should be zero. This is particularly reasonable in light
of two final relationships. First, the 20-minute survey measurements
themselves are probably accurate to no more than plus or minus 1 dB,
but the average differences between the 24-hour Leq(s) and L^n values
are on the order of only one-half dB. Second, the 95-percent confidence
intervals for the average Leq values derived from the 20-minute measure-
ments are much larger than the above one-half dB differences. Thus the
differences between Leq(8) and L(jn resulting from the 24-hour measure-
ments are very, very small when compared to the normal 20-minute survey
uncertainty, and do not represent a significant adjustment.
B-ll
-------
Development of Noise Zones
General
Via the data manipulations previously described, L^ values were
obtained for areas of various land use within the survey area. The land
use codes used to categorize the data for interior measurement sites were
assigned to the sites by an Ada County assistant planner. Thus, accuracy
of the land use assignments was assured. To indicate these assignments
and corresponding sound levels on a city map, a photograph from a Landsat
satellite was used. This photograph indicates the predominant land use
for each one-sixteenth mile square in the area by color. (The predominant
land use for each square is deduced by the satellite based on the reflected
and radiated light characteristics of each type of land use.) The Landsat
photo of the Boise area was simplified by the Ada County Staff to limit
the total number of land use types indicated. It is believed that
the land use assignments made by the assistant planner correspond well
with the land use interpretations of Landsat, and that the Landsat
photograph is an accurate pictorial display of the land use categories
for which L^n values have been established.
Additional areas were added to the Landsat photograph to show
distinctive sound patterns not directly related to land use. The central
business district core is represented as a separate commercial area
defined by the area's intense commercial buildings, activities, and
B-12
-------
traffic. The airport influence area is shown based on NEF-30 and NEF-40
contours prepared in a previous airport study. Noise zones that are
shown along roadways have widths determined according to the following
procedure.
Highway Noise Zone Boundary Determination
The following Table B-3 can be used to roughly estimate the width
of roadway noise influence zones along roadways in the Boise area. This
may be desirable where local planning or complaint difficulties arise.
The table is based on the mean L(jn values determined for roadway and
interior areas, and on a nominal attenuation of 4.5 dB per doubling of
distance from the roadway. It was assumed that, for the Boise sound
survey program, the average measurement distance from the roadway edge
was 15.2 m (50 ft) for roadway sites. The outer edge of the roadway
noise influence zone is taken to be the location where traffic sounds
from the subject road cease to measurably increase the average L 18000
Influence Zone Half Width-Roadway To
Zone Outer Edge-Without Buildings*
Residential /Parks Commercial /Indus trial
24.4 m (80 ft.) No Influence
58 m (190 ft.) 24.4 m (80 ft.)
67 m (220 ft.) 36.6 m (120 ft.)
*If buildings are present lining the roadway, the influence zone width
will equal,either the building setback plus the building length, or the
above distance, whichever is smaller. See text.
B-13
-------
To determine the influence zone width for a given roadway; note
whether there is a continuous line of buildings along the road. If so,
the influence zone will generally not extend beyond this first row of
buildings. For high volume roads in residential areas, some influence
may be apparent at the second row of homes, particularly if the size
of the spacing between the first row buildings approaches the average
building width. If buildings are not present close to the road, or
if the spacing is greater than building width, then the zone widths
given in Table B-3 for the various traffic volumes and land uses apply.
In general, the roadway noise influence zone widths should not exceed
those given in the table.
Data Reduction Program
The data reduction program (Figure B-3) was written in FORTRAN by
the Boise State University Urban Research Center. This program is
based upon a data reduction program developed by the EPA Region VI
office in Dallas, Texas.
B-14
-------
,OOS FORTRAN
003 t
0002
0093
0004
0005
0306
0007
0033
0009
0010
0011
0012
0013
0014
0015
0016
0017
001 R
001 3
0020
0321
0022
0323
0024
0025
0026
0027
0023
0029
0030
0031
0032
0033
00 34
0035
0036
OC37
0036
0339
0340
0341
0042
0343
0044
0345
0040
0347
0043
0049
0050
OJ51
0352
0053
0054
0055
0356
0057
00 53
0059
0060
0061
0062
0053
IV 360N-FO-479 3-9
MAINPGM
OAT;
12/15/77
TIME
12.£1.34
DIMENSION ENVIRt 18). SITE (13) . NOat 50) . NOB A ('! 0 J . LOB ( 55 I ,LDI3 A( 55 ) ,
lA4L<6).JAL«j),CASE<8).SOURCe<18),ALlO(24).AL 50(24). ALEQ (24).
2SUMN30! 50) , SUMO 1(50) , SUMD2C50I . SUM03{50 ) . C >£R < 5) , SI T 1 < 2 > . SECT<2),
3IMPACT(9) .COMMI 9) ,1 SAV{ 13.3) .SOURCU5 .3 )
DIMENSION *EATH( 10 24 . 3)
DIMENSION DAY5( 10 ) .TI MTAO(24 )
PEAL LDN.LNP .LUM.LUMM.NPL
INTEGER DAY, DAYS
DATA SAYS/' 10'. 11«, 12«,' 13'',« 14', 15'. 13". 3*' /
D4TA TMTAH/l.,2.,3.,».,5.,s.,7.,9..9..io.,ll.,12..13..14..15.«16.
1. 17. . 13. . 19. .20. .21. .22. .23.. 24. /
DATA IDAY1/' JO / ,1 DAY2/' 1 /.OAYS/' 2 '/.IDAY4/' 3 /
C****t«*****#4<*«*#*4*«***4*****««***************vt************, i *********
C THIS PROGRAM IS GOG3 FOR NOISE-LEVELS THAT FALL BETWEEN 1DB AND 99DB
C**********»**************»****«**4**************«****«*******«*********
ICOUMT=0
8030
8040
8010
PAGE 0001
C READ IN THE NUMBER OF DAYS NOT TO EXCEED 10.
RE A0(l ,8000) NOAYS
C
8000 FOR'-1AT( 12)
DD 8010 N=1.N3AYS
C READ IN 4 CARDS PER DAY WHICH CONTAIN THE 24 HOUR WEATHER INFORMATION
c NOTE: THE DAYS MUST BE IN ORDER AND THE DATA at HOUR MUST BE IN ORDER.
I=N
DO 8040 NI=1,3
Nl=< ( NI-1 )*3)+l
N2=N 1*7
RE ADC 1 .30 30 X ( WEATH( I . J.K) , K= 1 . 3 ) . J = N 1 ,N2)
FOW-(AT(8C A4 .F3.0.F3.0) )
CONTINUE
CONTINUE
N3A Y=l
03 f540 I =1,KKK
SUV,>I30 ( I ) =0.
SUMO1 ( I )=0.
SU'O2< I )=0.
SOM-53( I ) = 0.
840 CONTINUE
TOTN 30=0.
TOTD 1 = 0.
TOTD3=0 .
20OO CONTINUE
W^ITF ( 3. 73)
K£A->< 1 ,4. END =2 001) MACH. I SERNO .OPER tS IT1 .SECT, I SIC
ICOUNT = IC OUNT-t-1 »
4 F3RMAT( A I . I6.5A4, 2A3.2A3.I2I
WRITE(3.11> M*CH.ISEHNO.OPER,SIT1. SECT. I SIC
11 FOfiMAT( !'. 'MACHINE = . A 1 . 2X . SER I AL NO ='. I 6. 2X. OPERATOR ( S > =«.
15A4.2X. -SITE = .2A3.2X.' SECTION = . 2A 3. 2X . S 1C ='.I2>
RE43U .10) MCASES.(SITE< I ),I = 1,13>.MON. DAY. YEAR
10 FOR 4AT( It, 12A4, A2 .3A4 >
W» ITE (3. 50)
50 FDPMAT( 10 OH *******************************************************
1 **************************** *********** ****!»)
WRITE (J.ftl) (SITEd I .1=1 .13)
51 FOR'1AT( 3X.7HSITE = .13A4)
WHITE (3.52) MUN. DAY. YEAR. NCASES
52 FORMAT! 3X.7HDATE = . 3 A4 . 1 5X . 8HSHEETS ».I4)
WSITE (3.50)
IDATC=DAY
DO 99 M=l ,LLL
LDQ(M)=0
LDBA (M)=0
99 CONTI NUE
DO 100 M=1,KKK
NOSA ( M)=0
100 CONTINUE
SUM1 0=0.
SUM50=0.
KSUM=0
MMAX=0
MM IN=500
Figure B-3. Computer Program Used for Initial Data Reduction
B-15
-------
DOS FOST5AN IV 360N-FC-479 3-9
MAINPGM
;2/15/77
TIME
12.55.34
0064
0065
0055
0067
0068
0369
0070
007 1
0072
0073
007*
0075
0076
0077
0073
0079
0030
0011
0032
003 3
0094
0085
0036
0097
0033
0039
0090
0091
0092
0093
0094
0095
0096
0097
0093
009?
0100
'0101
0102
0103
0104
01 05
0106
0107
010S
0109
01 10
0111
0112
0113
0114
0115
01 16
01 17
01 1 3
0119
0120
0121
0122
,0123
0124
01?5
0125
01 27
012tJ
NC ASE=1
TS=00. 00
TF=00. 00
60
13
"N JGHT=0
1000 CONTINUE
WRITE (3,60) NCASE. < SITEt I ). 1 = 1 , 1 3> .MON.I) AY, YEAR
FDRMATt iX ,1 3.5X. 1 8HHOURLY I NFORM AT ION ,5X . 1 3A4, 3A4/ >
REAO(1,12> TS.Tr , (CASE( I ) « 1*1 .8)
F3RMAT( 2F5.2. 7A4.A2)
REAOU,4l) IMfACT. COMM
FORMAT ( 9A4, 9A4 )
Wfi I Tf:< 3. 42) I MPACT
FORMAT ( 1 X.' I MPACT =«,9A4|
WRITE<3.43> COMM
FORMAT ( 1 X, -GENERAL COMMENTS *=«,9A4>
C.EAD(1.13) ( ENV IRC I ) . 1=1 . 18)
FORMAT ( 18A4)
READ IN DESCRIPTION OF SOURCES
REAT(1,930> ( 30USCE{ I ) . I =1 . 12)
980 FORM ATC i 2 A6l
READ IN NUMBER OF SAMPLES
RiA3M«44) ( NJQ(N) . N=l .35 >
F3RMAT( 351 2)
RE MX! .45) ( ( I3AVJS , J) .SOURCU ,J),J»1»3)«!»1«8S
FORM A T( 2" ( 12 . Al ) I
PEAO( 1 ,46 ) « I SAV( I J) .SOURCt I . Jt » J = J .3 J . I"9, 15)
FOPMAT( 21 ( 12 . Al ) )
00 43 I =1 , 15
N=35tl
NDB( N!=0
DO 17 J=l ,3
NOB(N)-NJO(N)*ISAV(I.J)
CONTINUE
CONTINUE
W3ITF (3.61) TS.TF . (CASEd > .1 =1 .8)
F1RMAT( 3X .6HHOUR = , 3X , F 5 . 2 . 1 H- , F5« 2. 1 OX , 8A4 }
00 B050 1=1.10
IF ( OAY.CQ.DAYSI I ) ) GO TO 8060
CONTINUE
WRITEC 3,«355) ICOUNT.SIT1
FOPMAT( ,'OAY OOESN««T MATCH THE T ABLE '. 1* . "COUNT - . I 3. 1 X. ' SI TE
1 = . 1 X, 2A4 )
CALL COUMO (DAY. DAY, 0. OAVSU ) , DAYSt 10 J .0 )
OJ 8070 J-l .24
IF( TS.LE.T IMTASC J) ) GQ TO 8080
CONTINUE
WRI TEI3.3075) ICOUNT.SIT1
FORM<\T{ IX, TIME OOESN'«T MATCH THE T ABLE t X, COUNT « -.I3,1X«'SIT
IE = .1 X.2A4)
CALL POUMP ( TS ,TS .0 .TIMTABJ 1 ).TI^f AOC24). OJ
13
41
43
44
45
46
47
48
61
8050
8055
8060
8070
8075
C
C CHANGE TEMPERATURE TO CELSIUS
C
8080
62
931
63
TEMP=-( 5./9. ) *(32. -WE ATrl (I , J.2) )
W9ITEI3.62I WEATH(I.J.l) . TEMP, WE ATH( I . J.3I
FOWMAT(3X . "WEATHER :. 4X. -CONOITIONS = , A* .
l.'C .'.'WIND SPEED ='.2X,F3.&.» (KTs)')
'RI TE( 3,981 )
FORMAT(3X, 12A6)
WRITE (3,631
FDRMAT( U X.3-OB .4X,21HNUMOER OF OCCJRRENCE:. J
P=0
NT, rO8 (N)
Figure B-3. Computer Program Used for Initial Data Reduction
(Continued)
B-16
-------
DOS FORTRAN IV 360N-FO-479 3-9
MAINPGM
DATE
r i ME
0129
0130
0131
0132
0133
0134
0135
01 36
0137
0138
0139
0140
0141
0142
0143
0144
0145
0146
0147
0148
0149
0150
0151
0152
0153
0154
0155
0156
0157
01SB
0159
0160
0161
0162
0163
016*
0165
0156
0167
0163
0169
0170
0171
0172
0173
0174
0175
0176
0177
0178
OI7J
0193
.0181
01 fl2
0183
'0144
0165
0196
0167
0163
0189
IF tND3(N) .LE.O) ND8(N)=0
WRITE < 3,71 12) NS.NT.NDB(N) ,( ISAV( J . J ) .SOORC { J , J ) . Ja 1 . 3)
7H2 rO«MAT
7111 CONTINUE
71 F3RMATC SX ,I3.1H-.I3,2X,-I5)
72 FORMAT! IX ,2H )
73 FORMAT( 1H )
C FIND TOTAL NUMrJER OF SAMPLES FOR THE HOJR
ISIT1 = 0
DO. 101 N=l ,KXLK
N)
1Z.35*J»
PAGE 0003
101
75
7O1
CONTINUE
«RI TE (3,75) ISUM
FGRMAT( 3X.26HTOTAL NUMBER OF SAMPLES
Ft NO PERCENT OF TOTAL
AAL( 1 ) =.001*ISUM
AAL ( 2 )=0.01 *ISUM
AAL( 3)=00 .1*1 SUM
AAL(4)= ,5*ISUM
AAL(5)= ,9*ISUM
AAL( 6)= .99*1 SUM
SEARCH FOR LMIN
DO 704 N =1 ,KKK
IF(NDa(N)-l> 704. 701.701
CQNTIMUE
LMIN=2*N-1
,I4/>
GO TO 702
704 CONTINUE
SEARCH FOR LMAX
702 CONTINUE
DO 703 N =l.Ki
-------
DOS FORTRAN IV 360N-FO-4r? 3-9
MAINPGM
TI*«E
X2.55.34
01 90
0191
0192
019 3
01 95
01 95
0197
0193
0199
0200
0201
0202
0203
0204
0235
0236
0207
0203
0209
0210
021 1
0212
021 3
021 4
0215
0216
02 17
0213
0219
0220
0221
0222
0223
O224
0225
0225
0227
0229
O'JO
0231
0232
0233
0234
0235
0236
0237
0233
0239
0240
0241
0242
0243
0244
O.'-'.S
0246
02*7
0243
0249
0250
0251
DO 105 JJ=1.KKK
NOBA(JJ)=ND3(JJ)+NOBA(JJ)
LD3A(JJ)=LD3(JJ)+LDOA(JJ)
105 CONTINUE
KSUM=< SUM* I SU-I
IF(LMAX.GT.MMAX) MMAX=LMAX
IF( LMI N.LT.MMI N) MMIN=LMIN
PRINT OUT LN.NT.S.TNI AND
WRITE (3.76) LMAX
JAL(1>
J AL ( 2 )
JAL(3)
JAL(4)
JAL(5)
JAL(6)
PAG: ooo*
LNP (GAUSSIAN!
wm TE
WP ITE
W« I TE
»3 ITE
W^ ITE
W5 ITC
76
77
78
79
80
81
82
83
84
65
(3.77)
(.1.78)
{3,79)
(3.80)
(3.81)
(3,32)
WRITE(1,8J> L'MIN
rORMAT(1 OX,7HLMAK = .13)
FORMAT (IOX.7HL.1 = .13)
FDRMATI 1 OX,7HL1 = .13)
F3RMAr{10X.7HL10 = ,13)
FORMAT (IOX.T'HLSO = .13)
FORMAT (10X..7HL90 = ,13)
FORMAT (10X,7HI_99 = .13)
FORMAT (1CX.7-ILMIN = ,13/J
FORMAT (JX.6HTNI = .F5.1)
F3t5M^T (3X.17MLNP (GAUSSIAN ) .F3.1J
W-l ITE (3.34) 1 ixlIH
WRITE t3.B5) NPL
COMPUTE LAV AND MEAN
UNN=0.
DO 136 LL =1.KKK
PP = 0 .1 *(2.*LL-1.)
= FLOAT(NDB(I_L) ) /FLOAT ( I SUM!
= X°'J*10. *»PP
VBR=XPO*PP*10.
V5=VEtVER
106 CJNTIMUE
AV=10.*ALOG10(UNN)
A LI 0( NCASE ) = J AL(3 >
AL50( NCASS )= JAL(4)
ALEO( NCASF. )=AV
10+AL10( NCASE)/FLOAT(NCASES)
*,\L50-( NCASE)/FLOAT(NCASeS>
- A_£Q(NCASE)/FUOATI NCASES)
COMPUTE SIGMA AND LNP
D3Q=0.
DO 107 LL=1.KKK
FN=AOS( 2. »LL- 1 .-VE)
DQ=FLOAT( NDQ(LL) ) *FN*FN/FLOAT( ISUMJ
D:3Q = OT-fDOQ
107 CJMTINUE
. F5 . 1 )
C
C
LNP=AV*2.56*SIG
WRITE(J,39) LNP
WHIT=(3.37) AV
91 FURM AT OX, 6HLAV =
WR ITE( 3,12)
«9ITE( 3.50)
WHITEt 3.73)
INSERTED TO DO
GO TO 2000
c ****
C * INSERTED TO STOP PGM AT EOF
2001 STOP
C ****
2002 NCASE=NCASE+1
IFl.NCASE.LE.NC^SE:,) GO TO 1000
C«*4****** *********** + ** + *** + ***********»»**4i**«t«»»*»»**»*»»»*^»*»»<*»»»^»»»»»«
C START CALCULATIONS FOS THE WHOLE OAY
c FIND PERCENT OF TOTAL
c +
i CASE PER SITE
Figure B-3. Computer Program Used for Initial Data Reduction
(Continued)
B-18
-------
DOS FORTRAN IV 360N-FO-479 j-9
MAINPUM
0252
0253
0254
0255
0255
0257
0256
0259
0260
0261
0262
02&3
0264
0265
0266
0267
0?63
0269
0270
0271
0272
0273
0274
0275
027S
0277
0278
0279
0230
0231
0232
02S1
0234
0235
0236
0297
0233
0239
0290
0291
0292
0293
0294
0295
0296
0297
0293
0299
0300
0302
0303
0304
0305
0306
0307
0303
0309
0310
031 1
0312
0313
0314
0315
0316
0317
031 8
0319
0320
0321
AAL(1)=.001*KSUM
AAL(2)=0.01*KSUM
AAL( 3> = .1*KSUM
AAL(4)= ,5*KSUM
AAL(5)= .9*KSUM
AAL(6)= .99»K5UM
CALCULATE THE LN,
NE.S AND TNI
710
709
108
DO 1 03 MN=1 . 6
JSU=)=0
DO 709 NM =1 .KKK
KK=KKK-NM»1
J SU3=ND34 ( KK ) »-JSU9
IF< JSUS-AALCMN) > 709. 710. 710
CONTINUE
JAL( "N) =1 .*2.*KK
GO TO 103
CONTINUE
CONTINUE
TNI 0 = 4. *( JAL<3 >- JAL<5) >+< JAL(S>-30.)
COMPUTE LAV ANO MEAN
AVE = 0.
DUNN=0 .
DO 111 LL=1.KKK
POM=0. 1 *( 2.*LU*1.)
DQA=NDBA(LL)
=P XPR*1 0. **POM
Ill
AVER=EXPS *POM»10.
AVE= AVEvAVE:?
CONTINUE
AAVER=10.*AI_OG1 O(OUNN)
COMPUTE LON
UU.'4M=0.
D'J 119 LL = liLLL
PON=0.1*(2.*1_L*1.)
D3AL=L03A(LU )
EDN=DBAL/KSUM
LUM=EON*l 0.**PDN
119
C !
120
86
C
97
CONTINUE
LDN=10 .*ALOG10
SSO=FLOAT(NOOA(LL> ) *FN*FN/FUOATl KSUM)
CONTINUE
SIGMA=SORT(SSQQ)
WP ITE< 3, 72 )
V.R ITK 3.86) NDAY.t SITE(I).1*1.10) .MON.DAY.YEAft
FDR«AT( IX.I3.10X.17HDAILY INFORMATI ON.5X.10A5.3A4X)
WRIT;(3.63)
PRINT OJT AMPLITUDE DISTRIBUTION FOR THE DAY
DO 97 N=l,KKK
NS=2.*N+0
NT=NS*2
WRITe(3.71) NS.NT.NDBA(N)
CONTINUE
WSITF. ( 3. 72)
WRITF( 3. 75)
W4 ITF( 3.76)
WR IT=C 3.77) _
WRITEC 3.78) JAL(2)
W^ITc<3.79) JAL13)
WRITEO.SO) JAL(4)
W9IT=(3.81) JAL<5>
WRITEt 3.82) JAL<6>
WRITE(3.83) M^IN
WOITE'<3,34) TNIO
*RIT=(3,d7) AAVER
WSITE(3.90) KOAY.NIGHT
WRITEJ3.88) LON
KSUM
MMAX
Figure B-3. Computer Program Used for Initial Data Reduction
(Continued)
B-19
-------
PAGE 0006
DOS FORTRAN IV 360N-FO-479 3-9
MAINPGM
32/15/77
TIME
1?.55.34
0322
0323
032*
OJ25
0326
0327
0328
0329
0330
0331
0732
0333
0334
0335
0336
0337
0333
0339
0340
0341
03*2
0343
0344
0345
0346
0347
0349
0340
035O
0351
0352
0353
0354
0355
0356
0357
0351
0359
0360
0361
0152
0363
0364
0365
0366
0307
O363
0363
0370
0371
0372
0373
0374
0375
0376
0377
0373
0379
O^SO
03S1
0332
0113
0334
0365
0386
0387
0333
0339
0390
87
89
89
90
711
712
713
714
92
93
94
96
811
WRITEt 3.S9) LNP
WRITE(3.72)
FORMAT < 3X. 6HLF.O = .F5.1)
FORMAT(3X.6HLUN= .F5.1.5X,
174H 55 IS EPA IDENT.INTERFERENCE
2P5OT. LEVEL)
75 IS EPA INDENT.HEARING
.I2.19H DA/TIME HOURS AND .I2.16H NIGHTTIME HOUR
1IME HOURS)
WR I TEC 3.50)
EX81=0.
EX 7 5=0 .
EX65 = 0 .
EL45 = 0 .
00 711 J=27.KKK
EX81=ND3A(J)+EX81
CO NT I NUE
PG8l=EX31/KSJM*100.
DO 712 J=24.2'3
EX75=EX75+ND3A(J)
CONTINUE
PG 75=(EXrtl + t£ X75 ) /KSUM*100«
DO 713 J-1S.23
EX65=N03A< J)+ EX65
CONTINUE
PG65=(EX91!EX75+EX65)/KSUM*100.
PL65=130.-PG65
DO 714 J=8,KK><
EL45=EL45<-ND3A)
DSA .F6.2.20H PERCENT OF THE TIME.3X.
STRONGLY OISCOU'JAGEO CHUO))
FORM AT(3X.I5HEXCEEDS 75
147H 33.3 PERCENT (24HR)
FORMAT(3X,15H=XCEEDS 65
148H 33.3 PERCENT (24HR)
F03MAT(3X.15HEXCEEDS 45
148H 33.3 PERCENT (24HR)
WR ITE( 3.50)
Rl =0.
R2=0.'
R3 = 0.
S10=0.
S50=0.
SEO=0.
OD 111 I=1,NCASES
S10=S10<-(AL10( I)-SUM10)**2
S50=S50*(AL50(I)SUM50)**2
SEQ = SEO«-( ALEQC I >-SUMEQ) **2
Rl=41t(AL10( I )-SUM10)« ( ALEOd )-SUMEQ)
O3A .F6.2.20H PERCENT OF THE TIME.3X.
NORMALLY UNACCtPTABLE (HJO)>
DBA .F6.2.20H PERCENT OF THE TIME.3X.
NORMALLY1 ACCEPTABLE *(AL1 0(1 J-SUM! 0)
CONTINUE
SIG=SUr
-------
PAGE 0007
DOS FORTRAN iv 360N-FO-A79 3-9
MAINPGM
DATE
3/77
TIME
12.55.34
0331
0292
0333
0394
0335
0396
0197
0?9d
0399
0400
0*01
0*02
0*33
0434
0*05
0*06
0407
0409
0410
04 1 1
041 >
0413
041 4
041 5
0415
0417
041 3
041 9
0420
04il
0422
0423
043*
0426
0426
0*27
0423
042 )
0430
04M
0432
0433
0434
0435
0435
0437
0438
043?
0443
0441
0442
0443
04*4
815 FDPMATC 5X , IOHL10 =.F7.3)
816 FOHAT< 5X .10HL50C AVE) =,F7.3>
817 F3RMATC5X. 10HLEOCAVE) =.F7.3)
818 FORMAT(5X.9HSIG(10) =.F7.3)
819 FORM AT ('JX, 9HSI GC50 ) =,F7.3)
820 FORMAT ( 5X, 9^1 G( HO) =.F7.3)
c**************
c
c***********«***
IF( IDA TF..NE. l.OAYl ) GO TO 830
DO 639 K=l,
SUMN30C K) =SUMN30CK ) 4-RATIO
839 C3NTINUF
G3 TO S53
830 CONTINUE
IF(IDATE.NE.IDAY2) GO TO 831
DO 341 K=l,KKK
RAT I 0=FLOAT( ND8A(K) )/FLOAT«SUM>
SUXOK K)=SUM31CK)*RATIO
841 CONTINUE
G3 TC -353
831 CONTINUE
Ir(IOATE.NE.IDAY3) GO TO 832
DO 342 K=I .KKK;
RA TI 0 = FLOAT( rOBA(K) ) /Fl_OAT< KSUM)
SUM:) 21 K )=SUMD2( K) *RATI O
842 CONTINUE
GO TQ S53
832 CONTINUE
IF(I3ATd.NE.IDAY4) GO TO 813
DO 343 K=l,KKK
RATIG=FLJAT(ND3A(K)>/FLOAT
-------
APPENDIX C
EQUIPMENT DETAILS
The two levels of temporal sampling used in the survey required two
types of instrumentation. For the manually collected data, the observa-
tion teams employed ANSI Type 2 sound level meters (with windscreens)
mounted on tripods. The sound level meters were calibrated prior to and
immediately after each day's session utilizing a compatible acoustic
calibrator. (Figure C-l depicts the manual collection of data.) Quiet-
period nighttime measuremants were taken with a B&K ANSI Type I sound
level meter.
The 24-hour surveys required a more sophisticated system. The noise
signal detected by the B&K 4921 outdoor microphone system (Figure C-2) was
fed into the Metrosonics dB-602 Community Noise Analyzer (Figure C-3) which
digitized the data at a rate of one sample per second, classified the data
into 100 bins each one decibel wide and computed the hourly Leq, L^Q, ^50,
and Lgo- The information was stored for an internal solid-state memory
from which it was read out at the end of each 24-hour period.
The B&K 4921 microphone system contains a 1/2 inch air condenser
microphone, assembled in a comprehensive weather and moisture-proof
arrangement including windscreen, raincover, bind spike, and humidifier.
Using the build-in electrostatic actuator, the system was calibrated at
the start and conclusion of each 24-hour period. The microphone was
connected to the community noise analyzer via a 30-meter cable.
C-l
-------
k
Figure C-l. Field Personnel Preparing to Collect a
20-minute Noise Sample Using Sound Level Meter
C-2
-------
Figure C-2. Outdoor Microphone in Place for
24-hour Data Collection
C-3
-------
Figure C-3. Community Noise Analyzer
C-4
-------
APPENDIX D
DATA FORMS AND INSTRUCTIONS
All project personnel who performed 20-minute measurements received
personal training in sound level meter use and field data acquisition
techniques. Only after this practice were instrument operators sent
into the field. The written data collection package given to each
operator or team consisted of:
o Cover sheet indicating the exact 540 m (1/3-mile) square cells
containing the sites to be measured.
o Complete list of procedures for obtaining and recording a
20-minute sample of data at a given site.
o Figures indicating preferred microphone placement for different
types of sites (e.g., grid site, roadway site, etc.).
o An example data sheet showing correct procedures for comple-
tion and data logging.
o Blank data sheets to be completed.
o A large scale map upon which was marked the intended measurement
location.
Examples of these items (with exception of the map) are presented
in this appendix. Note that the data sheet easily allows the observer
to record comments and a site sketch as well as sound level data.
D-l
-------
Telephone number for Section: Cells;
assistance: 384-4394
Section: Cells:
Section: Cells:
Name: Phone No:
Name : Phone No:
Date:
SLM:
Model
S.N.
D-2
-------
TEST PROCEDURE
1. Write name, date, and section number assigned in upper right hand
corner of Data Log Book.
2. Locate site.
3. Fill in top part of Data sheet.
4. Set up tripod at test site. Make sure SLM is in a vertical position.
5. Make sure windscreen is on microphone.
6. Place weighting adjustment to A.
7. Place fast-slow adjustment to slow.
8. Turn meter on.
9. Set dB adjustments according to noise levels at test site.
10. Take dB reading every 15 seconds and record for a 20-minute period.
11. Turn off SLM at end of 20 minute period.
12. Total up readings on data sheet.
13. Fill in post-survey comments.
14. Move to next test site.
D-3
-------
AREA
Green Mark
House
fi Ft. (2mT
(2m)
- - jtoad
Use standard distance of 50 ft./in all applications if no building is at site
Whichever one is closer
(>18,OOOADT)
Blue Mark
House
7TI
6 Ft. (2m)
100 Ft. (30m)
OR
Curb
Road
LQ
(6000
-------
PRL-SURVtY CUMHLU
/^\irvdi t\/\ v ^ \ «-*^*
Kj* ^n \ * *OU ^*» *j » ^* ^M«
b:
V
s ojoio oWAmft
4-/>ftK^a^^q ^60^ skps
.a
-il
SITE
-
V
SKETCH:
~
, 100
A-WEIGHTED SOUND LEVEL, DECIBELS
M
SO
- -
^
-
"V*
-
Cl-fk
HaU
5
r
r
i ! _,
1
i
t1
f
i
(C
90
^
1
]Q_
i
i
I
t
1 1
1
Jl
fl
44 //
////
T^W. ^
[]7f
flNtiTs
#/«
ill
tfk
n
*
T*) In
.
^
a
"""O
/
£/
10
1
10
t
Jl/ 1
7
«
(
90
| 1
! i i
1
i
X)
i
1
1
i
1
1
M
I
l
I
,:
i1-
'
J
1
.j..
X
,
1
,
^.' . 1 L Iv/M.
OF
Da
Tir
Da
M
jerafor S lM6i& i/-
hp -J2' /£?/1 T2^-
nfl 'C^ C/
o so:£O
y S M T W Th
icro. Dishance fo V/a
POST-SURV
IMPACT -
7
;;*(
"T"'
23 ; '*ita.
M
,.*""
i
r
«
».' S
1&
j
_]
1
i
r
I
1
1
1
Ufe-J'A
EY COMMEN
i/a-Vo^
J 1 1 L
Site No .UL
^S^
r- ,vi^"
I ''
"Wfll
JS!
A k
i
n*
!
4C
1
j
1
J, | W ."X.
t
*?
1
1
70
t
l
"
»
O
t
.o
0
/
^
^-
^-
/o
V
(I
^-
f
ft
1-
a.
Code for Noises
Above 70 dB
.F F"^n vrn
P S.MALL PLAfJE
H HELICOPTER
R RA1LROAO ;
T TRUCK
A AUTO
3 BUS
M ,-MOTCflCYCLE
W ; WATER CRAFT
V OFF "0 VEH
MACHINES
C CONSTRUCTION EOUB
F FACTORY EQUIP.
h .HOUSEHOLD EQUIP.
OTHER
D DOO
1 LOUD SPEAKERS
NUMBER OF READING
D-5
-------
S
A-WE1GHTED SOUND LEVEL, DECIBELS
N.
GENERAL
/ / *» '
nnL., / I ( i 1 ~7W
r/
Pay
Wind .c
Temp,
i"
"<.
S M ^
jpeed
We
?athe
g w
P-^KUM
r
Th F S
Direction
Rel. Hum
1
<
(
\
1
<
(
EQUI
- i
Fype.
>eria
:a .
Vucro
v^icro
5LMS
Dther
SITE SKETCH /
*«
,**>
^V
;»*-
**>\
7^1
jz£
--
-
^-
^ W \ n 1
100
4
*
90
4
2
BO
«
4
f
'70
4
«C
i
tf
4f
I
/
i
(
l
i
1
5
-rr
II
til-
'f'''
'.
--
Hi
t>
n
/
///j
!.*.
r
i/"iiHf
-
f I f-^
ll / 1 /
^
H/
J ;.
-
1
...
i
f
ij-tf
j
10 B
!
!
1
i
j !
1
"*
i
I
20
j
i
i
1
IO IS
*0 K1
>t^
HYI
^ i
ir
i
HUI
;
20
1
\
C
PMENT S
i p ( .j > - ! "^ C3
#
Dat<
.He
.D
'.I
J5
i !
ight
stan
ce
toWa
Fast,
i
^
(
ii ^ t* ^^ j^V ^7 ^fcjf
;tp NO 5 i"^ ^~^
1 r,rnt;nn ^^C.V>ft^?
V)
1
i
1
i
i
i
i
c
S.
e
><
Count: Auto:
... . Other
,,* LOi^) r
Total
'Umh>le D-P
?. ~^ofo,,) r^n(_-/?Pc/
« Total
~h^rr
i
j_.
50 J6
fO TO
i
4C
K
9?
r
30
i
2
n
TO
S3
t
!
K>
I
~~s.
h
^
-r
T
T
Code for Noises
Above 70 dS
F FWf? VI-H
p SMAI ( PI Mlf
J JET
H HELICOPTER
R_ RAILROAD
T _ . _ TRUCK
A AUTO
R , . RIS
M MOTO"CYC1 E
ft WATER CRAFT
Vffc an VFII
MACHiNERf
Y YARD MAINT. EQUIP.
F FACTORY EOUP.
h . nnii<3reiO( p FpiitP
OTHER
0 OCG
1 .LOUD SPEAKERS
-
ii
to.
NUMBER OF READINGS
D-6
-------
APPENDIX E
24-HOUR DATA
The 24-hour data obtained with the community noise analyzer are
presented in this appendix. Note that the summary sheet (Table E-l)
indicates that some of the measurements were repeated during different
days at the same site. Following the summary is an individual tabula-
tion and 24-hour graph for each site showing hourly levels of L , LQQI
L,-nl and L.n, and daily values of L and L, .
E-l
-------
Table E-l
Summary of 24-Hour Measurements of Noise
in Boise, Idaho, January 1977
Location
City Hall Roof
(SW 1/4)
City Hall Roof
(SW 1/4)
City Hall Roof
(SW 1/4)
7111 McMi-llens
2040 Penninger
2800 No. Frye
?505 Harrison
18148th Street
217 Redfish Lane
1050 Krall Street
1814 8th Street
1050 Kroll Street
1790 Hill Road
Terrace
300 Coitin
Start
Day
1/7
Fri.
' 1/8
Sat.
1/10
Mon.
1/12
Wed.
1/12
Wed.
1/12
Wed .
1/13
Thurj.
1/13
Thurs.
1/13
Thurs.
1/14
Fri.
1/14
Fri.
1/18
Tues.
1/20
Thurs.
Time
1730
1730
1030
1530
1530
1830
}730
1730
1930
1830
1930
1930
1830
1930
Finish
Day
1/8
Sat.
1/9
Sun.
1/11
Tues.
1/13
Thurs.
1/13
Thurs.
1/13
Tnuri.
1/14
Fri.
1/14
Fri.
1/14
Fri.
1/15
Sat.
1/15
Sat.
1/19
Wed.
1/21
Fri.
Time
1630
1630
0930
1430
1430
1730
1630
1630
1830
1730
1230
1330
1830
1930
Leq (24)
(dB)
61.0
59.0
62.0
56.0
59.0
43.0
54.0
56.0
50.0
50.0
52.0
47.0
58.0
53.0
Ld (dB)
(0700-2200)
60.1
56.5
63.8
57.5
61.1
44.1
55.2
58.0
52.0
51.5
53.5
47.3
60.0
54.3
LJdB)
(2200-0700)
62.4
61.2
58.8
51.3
49.1
37.0
43.1
47.8
40.5
42.0
50.8
46.7
48.7
45.1
Ldn
(dB)
68.5
67.1
66.0
59.0
60.0
45.0
57. C
58.0
52.0
52.0
58.0
53.0
60.0
55.0
Land Use or Local
Noise Source
Road
Road
CBD
Residential
Airport
NEF 30-NEF 40
Boundary
Residential
Arterial
-------
Table E-2
24-HOUR DATA SHEET
Location: City Hall Roof
Serial Number of Mike: 506149
EPA Property Number of Analyzer: 063019
Operator: -
Start
Finish
Date
1-7-77
1-8-77
Time
17:30
16:5U
All Descriptions in. Decibels
Hour
1730
1830
1930
2030
2130
2230
2330
2430
0130
0230
0330
0430
0530
Leq
55
58
61
62
61
62
63
62
62
63
63
63
62
L10
57
61
62
64
63
64
64
64
64
64
64
64
63
L50
49
53
56
58
59
60
60
60
60
60
60
61
61
L90
47
48
50
53
54
55
56
56
57
57
56
57
57
Hour
0630
0730
0830
093U
1030
1130
1230
1330
1430
1530
1630
L
eq
61
61
62
6Z
62
60
60
56
55
51
56
L
10
63
63
63
63
63
62
62
59
56
52
55
L50
60
59
58
59
59
59
56
55
51
49
47
L
90
55
54
54
54
54
52
50
47
... ._ .. .
47
46
46
69 <*
59.0 dB (9-5)
E-3
-------
Summary of sound levels at
City Hall - January 7 , 1977
DAY-NIGHT AVERAGE LEVEL
(Ldn): 68'5 dB
HOURLY INFORMATION
CQ
O
w
PI >
I W
p
o
12
NOON
24
MIDNIGHT
TIME OF DAY
-------
Table E-3
24-HOUR DATA SHEET
Location: City Hall Roof
Serial Number of Mike: 506149
EPA Property Number of Analyzer:
Operator: R.R.
063019
Start
Finish
Date
1-8-77
1-9-77
Time
17:30
16:30
All Descriptions in Decibels
Hour
1730
1830
1930
2030
213U
2230
2330
2430
0130
0230
0330
0430
0530
Leq
54
55
55
59
e>u
60
61
61
62
61
61
61
62
L10
57
58
58
61
62
62
63
63
62
63
63
63
63
So
48
49
50
51
55
56
57
59
58
57
58
57
59
So
47
48
48
49
52
50
50
54
53
55
53
52
54
Hour
0630
0730
0830
0930
1030
1130
1230
1330
1430
1530
1630
L
eq
61
60
60
58
57
54
55
49
47
50
52
So
62
62
61
61
59
57
56
50
46
49
55
So
58
57
56
55
54
52
48
45
41
40
41
L
90
54
54
52
52
57
49
47
40
40
38
39
udn
67 dB
54.2 dB C9-5)
E-5
-------
Summary of sound levels at
City Hall - January 8, 1977
DAY-NIGHT AVERAGE LEVEL
(Ldn): 67.1 dB
HOURLY INFORMATION
03
O
w
M >
I W
ON J
P
o
to
12
NOON
16
24
MDOTGHT
TIME OF DAY
-------
Table E-4
24-HOUR DATA SHEET
Locations City Hall Roof
Serial Number of Mike: 506149
EPA Property Number of Analyzer: 063019
Operator: Konheim
Start
Finish
Date
1-10-77
1-11-77
Time
09:50
11:50
All Descriptions in Decibels
Hour
1030
1130
1230
1330
1430
1530
1630
1730
1830
1930
2030
2130
2230
Leq
64
65
64
65
66
65
65
63
62
61
59
60
58
L10
64
65
65
65
66
66
65
64
63
62
62
62
61
L50
61
62
62
62
63
63
62
60
59
57
57
56
54
L90
57
59
60
60
60
60
59
56
54
52
51
i
51
49
Hour
2330
2430
0130
0230
0330
0430
0530
0630
0730
0830
0930
1030
1130
L
eq
61
55
54
52
51
52
57
63
64
64
64
65
66
L
10
59
58
55
51
51
54
60
71
71
67
63
63
64
L50
51
49
47
46
47
47
52
60
60
61
63
63
64
So
47
46
46
45
45
46
47
54
54
58
60
60
60
66 dB
65.3 dB (9-5)
E-7
-------
Summary of sound levels at
City Hall - January 10, 1977
DAY-NIGHT AVERAGE LEVEL
(L): 65.7dB
HOURLY INFORMATION
P3
d
»
O
CO
5: 30 to 7: 30 a.m. not shown because of
instrumentation failure.
12
NOON
16
24
MIDNIGHT
TIME OF DAY
-------
Location: ' 7111 McMullens
Serial Number of Mike: 506149
EPA Property Number of Analyzer:
Operator: AK
Table E-5
24-HOUR DATA SHEET
063019
Start
Finish
Date
15:00
I4:4b
Time
All Descriptions in Decibels
Hour
1530
1630
1730
1830
1930
2030
2130
2160
2330
2430
0130
0230
Leq
59
60
58
59
60
54
'62
bZ
54
51
55
49
L10
54
53
56
54
56
53
58
b!5
54
51
51
49
L50
48
50
49
49
49
48
50
bl
50
49
48
48
So
45
48
47
47
47
47
48
48
49
47
47
46
Hour
0330
0430
0530
0630
0730
0830
0930
10.50
1130
1230
1330
1430
L
eq
49
48
49
47
48
51
52
bt>
55
57
57
56
Lio
49
48
48
48
49
45
50
bb
55
55
53
53
L50
47
47
46
46
47
47
48
48
48
48
47
48
L
90
46
46
44
45
43
44
46
4t»
44
47
45
46
Ldn
eq
59.3 dB
57.1 dB (9-5)
E-9
-------
Summary of sound levels at
7111 McMullen Drive
DAY-NIGHT AVERAGE LEVEL
(Ldn): 59.3 dB
HOURLY INFORMATION
PQ
g
iJ
>
w W
t- i-5
o
CO
12
NOON
16
24
MIDNIGHT
TIME OF DAY
-------
Table E-6
24-HOUR DATA SHEET
Lociution: 2040 Penninger
Serial Number of Mike: 526575
EPA Property Number of Analyzer: 019156
Operator; R«R.
Start
Finish
Date
1-12-77
1-13-77
Time
14:15
14:50
All Descriptions in Decibels
Hour
1530
1630
1730
1830
1930
2030
2130
2230
2330
2430
0130
0230
Leq
56
63
64
57
59
56
67
57
49
41
48
46
L10
47
56
40
49
50
50
45
42
43
42
41
41
L50
41
43
t
45
43
41
40
39
37
36
38
38
38
L90
43
39
39
41
38
39
38
37
35
35
36
36
Hour
0330
0430
0530
0630
0730
0830
0930
1030
1130
1230
1330
1430
L
eq
42
37
37
41
40
49
62 .
62
58
62
63
47
Lio
41
38
38
42
41
46
55
50
51
56
54
47
L50
35
35
35
38
39
40
40
39
41
43
41
43
L
90
36
33
33
33
36
37
38
37
38
39
39
41
Jdn
eq
= 60.4 dB
= 60.9 dB (9^5)
E-ll
-------
Summary of sound levels at
2040 Penninger - January 19, 1977
DAY-NIGHT AVERAGE LEVEL
(Ldn): 60.4dB
HOURLY INFORMATION
30
TIME OF DAY
-------
Table E-7
24-HOUR DATA SHEET
Location: 2800 N. Fry
Serial Number of Mike: 442933
EPA Property Number of Analyzer:
Operator: 063020 R.R.
063020
Start
Finish
Date
1-12-77
1-13-77
Time
16:55
17:35
All Descriptions in Decibels
Hour
1830
1930
2030
2130
.2230
2330
2430
0130
0230
0330
0430 i
Leq
47
41
41
46
38
43
37
34
34
34
32
L10
47
42
43
47
34
38
35
35
33
33
30
L50
36
33
33
31
30
30
32
31
30
30
30
So
33
31
30
30
30
30
30
30
30
30
30
Hour
0530
0630
0730
0830
0930
1030
1130
1230
1330
1430
1530
1630
1730
L
eq
31
35
46
44
44
48
41
42
43
41
40
42
45
Lio
31
55
53
41
41
45
40
42
42
38
39
41
44
L50
30
52
34
36
35
36
35
36
34
33
34
35
"i
34
So
30
50
30
32
55
55
54
34
35
51
51
52
51
Ldn = 45-4 dB
eo - 43.4 dB £9-5)
E-13
-------
Table E-8
24-HOUR DATA SHEET
Location: 2205 Harrison
Serial Number of Mike: 506149
EPA Property Number of Analyzer:
Operator: R.R.
063019
Start
Finish
Date
1-12-77
1-13-77
Time
16:15
16:35
All Descriptions in Decibels
Hour
1730
1830
1930
2030-
2130
2230
2330
2430
0130
0230
0330
Leq
57
56
54
54
53
52
53
49
47
47
39
L10
59
58
57
56
55
55
55
52
49
43
37
L50
53
55
51
50
47
46
46
39
35
32
31
Lro
Hour
0430
0530
0630
0730
0830
0930
1030
1130
1230
1330
1430
1530
1630
L
eq
39
39
41
51
56
56
53
55
55
56
56
56
56
So
32
55
38
53
58
57
56
55
57
58
58
58
58
L50
31
51
32
41
53
51
48
48
51
52
51
52
52
So
= 56.5 dB
= 55.5 dB (9-5)
E-14
-------
Summary of sound levels at
2205 Harrison Blvd. - January 12, 1977
DAY-NIGHT AVERAGE LEVEL
(L): 56'5 dB
HOURLY INFORMATION
CQ
W
w >
O
CO
40
30
12
NOON
16
24
MIDNIGHT
20
TIME OF DAY
-------
Table E-9
24-HOUR DATA SHEET
Location: 1814 8th Street
Serial Number of Mike: 526575
EPA Property Number of Analyzer:
Operator: R.R.
019156
Start
Finish
Date
1-13-77
1-14-77
Time
15:50
18:30
All Descriptions in Decibels
Hour
1730
1830
1930
2030
2130
2230
2330
2430
0130
0230
0330
0430
Leq
59
58
53
55
50
51
52
50
48
46
44
39
L10
60
59
56
56
52
53
54
50
48
43
35
34
L50
48
50
45
43
38
40
40
35
34
34
33
33
So
40
39
37
35
34
35
34
33
33
33
32
32
Hour
0530
0630
0730
0830
0930
1030
1130
1230
1330
1430
1530
1630
1739
1830
L
eq
42
39
48
51
59
53
57
61
59
60
61
62
61
58
Lio
34
38
48
53
58
56
56
58
61
' 64
65
66
65
61
L50
33
35
39
41
46
42
44
43
46
46
48
53
52
53
L
90
32
33
37
36
59
39
39
38
38
38
39
42
43
44
L^ = 58 dB
L_ = 59.7 dB. (9-5)
E-16
-------
Summary of sound levels at
1814 Eighth Street - January 13, 1977
DAY-NIGHT AVERAGE LEVEL
(L>: 57.7dB
HOURLY INFORMATION
30
12
NOON
24
MIDNIGHT
TIME OF DAY
-------
Table E-10
24-HOUR DATA SHEET
Location: 217 Red Fish Lane
Serial Number of Mike: 442933
EPA Property Number of Analyzer: 063020
Operator:
RR
Start
Finish
Date
1-13-77
1-14-77
Time
18:2U
18:35
All Descriptions in Decibels
Hou-
1930
2030
2130
2230
2330
2430
0130
0230
0330
0430
0530
0630
Leq
44
52
45
45
43
32
. 34
35
38
35
42
42
L10
39
42
44
45
35
32
34
36
36
35
40
42
L50
34
34
34
34
31
31
32
32
33
33
36 '
37
L90
32
32
31
31
30
30
31
30
31
30
34
35
Hour
0730
0830
0930
1U3U
1130
1230
1330
1430
1530
1630
1730
1830
L
eq
43
53
55
bl
56
51
51
52
56
53
50
46
Lio
43
48
50
50
50
44
48
49
53
54
53
51
L50
40
41
43
4b
47
45
43
46
41
40
41
38
L
90
37
37
40
41
43
40
39
38
36
36
38
36
Ldn = 51.5 dB
Leq = 53.6 dB (9-5)
E-18
-------
Summary of sound levels at
217 Redfish Lane - January 13, 1977
DAY-NIGHT AVERAGE LEVEL
(Ldn): T
HOURLY INFORMATION
30
12
NOON
16
24
MIDNIGHT
TIME OF DAY
-------
Table E-ll
24-HOUR DATA SHEET
LocationlOSO Krai 1 Street
Serial Number of Mike: 506149
EPA Property Number of Analyzer:
Operator: R R.
063019
Start
Finish
Date
1-13-77
1-14-77
Time
17:10
18:35
All Descriptions in Decibels
Hour
1830
1930
2030
2130
2230
2330
2430
0130
0230
0330
0430
0530
Leq
53
51
42
46
46
47
42
38
38
38
38
37
L10
47
50
44
45
45
48
42
39
37
37
38
37
L50
40
38
38
38
43
37
35
36
36
36
35
So
38
36
36
36
35
35
34
35
35
33
34
Hour
0630
0730
0830
0930
1030
1130
1230
1330
1430
1530
1630
1730
1830
L
eq
37
40
43
47
48
49
48
47
47
49
54
60
Lio
37
40
43
49
50
48
48
48
45
46
58
56
58
L50
38
40
S3
43
42
43
42
40
40
43
43
45
42
So
36
38
41
42
41
41
40
38
38
39
39
42
41
Ldn = 51.7dB
L =49.3 dB(9-5)
E-20
-------
Summary of sound levels at
1050 Krall Street - January 13, 1977
DAY-NIGHT AVERAGE LEVEL
(L): 51.7dB
HOURLY INFORMATION
PQ
O
$5 70
W
"
I W
60
50
40 -
30
12
NOON
16
24
MIDNIGHT
TIME OF DAY
-------
Table E-12
24-HOUR DATA SHEET
Location: 1814 8th Street
Serial Number of Mike: 526575
EPA Property Number of Analyzer:
Operator:
019156
R.R.
Start
Finish
Date
1-14-77
l-lb-77
Time
18:35
12:11)
All Descriptions in Decibels
Hour
1930
2030
2130
2230
2330
2430
0130
0230
0330
0430
0530
0630
Leq
56
55
54
52
53
51
53
52
47
49
50
38
L10
58
57
56
56
55
52
55
53
47
42
40
37
L50
48
46
45
43
43
41
41
41
39
37
36
36
L90
41
41
40
39
40
39
38
39
37
36
35
35
Hour
0730
0830
0930
1030
1130
1230
L
eq
46
47
53
53
54
55
Lio
43
45
54
53
56
59
L50
36
38
41
42
44
45
L90
37
36
38
39
40
40
E-22
Ldn = 58
Leq = 53.8 dB C9-5)
-------
Summary of sound levels at
1814 Eighth Street - January 14, 1977
DAY-NIGHT AVERAGE LEVEL
U): 58.0dB
HOURLY INFORMATION
30
12
NOON
16
24
MIDNIGHT
TIME OF DAY
-------
Table E-13
24-HOUR DATA SHEET
Location: 1050 Krall Street
Serial Number of Mike: 506149
EPA Property Number of Analyzer:
Operator: R . " R.
063019
Start
Finish
Date
1-14-77
1-15-77
Time
18:35
12:55
All Descriptions in Decibels
Hour
1930
2030
2130
2230
2330
2430
0130
0230
0330
0430
0530
0630
^
50
49
47
45
45
46
48
51
45
49
39
38
L10
48
48
[8
46
45
46
49
54
46
52
39
39
L50
43
43
42
42
42
42
42
40
40
37
37
37
So
42
41
40
40
41
40
40
38
37
36
36
36
Hour
0730
0830
0930
1030
1130
1230
1330
L
eq
40
42
44
48
49
48
47
Lio
40
42
43
50
51
49
46
L50
39
41
44
44
43
42
42
L
90
33
40
42
42
42
40
40
Ldp = 53.2 dB
E-24
-------
Summary of sound levels at
1050 Krall Street - January 14, 1977
DAY-NIGHT AVERAGE LEVEL
(Ldn): 53.2 dB
HOURLY INFORMATION
90
80
ffl
O
70
p
§ 60
O
to
50
40
30
12
NOON
24
MIDNIGHT
TIME OF DAY
-------
Table E-14
24-HOUR DATA SHEET
Location: 1790 Hill Road Terrace
Serial Number of Mike: 442933
EPA Property Number of Analyzer: 06302
Operator: AGK
Start
Finish
Date
1-18-77
1-19-77
Time
17:48
23:42
All Descriptions in Decibels
Hour
1830
1930
2030
2130
2230
2330
2430
0130
0230
0330
0430
0530
0630
0730
Leq
59
57
56
56
55
50
46
45
41
39
39
43
51
58
L10
62
61
60
59
58
52
42
38
33
33
34
37
50
62
L50
54
51
47
46
46
37
33
33
32
32
32
33
40
52
L90
45
44
42
41
41
34
32
32
32
32
32
33
35
44
Hour
0830
0930
1030
1130
1Z30
1330
1430
1530
1630
1730
Le,
60
58
60
58
61
61
60
62
63
63
Lio
63 !
63
63
63
63
63
64
65
66
66
L50
57
57
50
50
53
53
53
55
58
60
L90
50
50
45
45
4b
45
44
45
48
54
r = 59.6 dB
on
eq
= 60.7 dB(9-5)
E-26
-------
Summary of sound levels at
1790 Hill Road Terrace - January 18, 1977
DAY-NIGHT AVERAGE LEVEL
(Ldn): | 59.6 dB
HOURLY INFORMATION
30
12
NOON
24
MIDNIGHT
TIME OF DAY
-------
Table E-15
24-HOUR DATA SHEET
Location: 300 Costin Street
Serial Number of Mike: 442933
EPA Property Number of Analyzer:
Operator: Konheim
063020
Start
Finish
Date
1-20-77
1-21-77
Time
1908
2010
All Descriptions in Decibels
Hour
1930
2030
2130
2230
2330
2430
0130
0230
0330
0430
0530
0630
Leq
52
52
49
50
47
46
43
33
33
38
39
48
L10
50
48
45
38
35
35
32
32
32
32
33
40
So
36
55
33
32
32
32
32
32
32
32
32
33
L90
33
33
32
32
31
31
31
30
30
31
31
32
Hour
0730
0850
0930
1030
1130
1230
1330
1430
1530
1630
1730
1R-W
1930
L
eq
59
54
54
52
54
55
53
53
56
56
54
^4
53
Lio
62
54
54
52
51
53
52
48
52
56
55
55
50
L50
40
38
38
42
39
38
40
38
40
41
39
42
37
L
90
34
34
34
34
35
35
36
35
37
36
36
34
33
Ldn ° 54'7dB
Leq = 54.3 dB (9-5)
E-28
-------
Summary of sound levels at
300 Cosin Street - January 20, 1977
DAY-NIGHT AVERAGE LEVEL
HOURLY INFORMATION
30
12
NOON
16
24
MIDNIGHT
TIME OF DAY
------- |