HomeMy WebLinkAboutJim Rogers CorrespondenceJune 4, 2003
Clerks Office
City of Meridian
33 E. Idaho
Meridian, Idaho 83642
James L. Rogers
1115 Rolling Hills Drive
Meridian, Idaho 83642
RECEIVE
aura I; ~ zoos
CITY OF MERIDIAN
CITY CI ARK nFFIrF
I have enclosed 8 documents concerning Helicopter Noise in an Urban Environment.
I would appreciate it very much if you could provide copies of these documents to the
Mayor and City Council Members for the June 10 Council meeting concerning St. Lukes
request for a Helipad located on their property on Eagle Road.
Thank You,
~~
'games L. Ro ers
g
887-1093
Chapter
NOISE ANALYSIS
INTRODUCTION
J~P~ ;1 ti ZIit~3
CITY OF MERIDIAN
CITY CLERK OFFICE
A preliminary study to assess the noise impact of pro-
posed helicopter operations at San Francisco General
Hospital (SFGH) was conducted by Charles M. Salter
and Associates in January 2003. This purpose of the
study was to help in determining the feasibility of locating
a dedicated helipad on the medical campus of SFGH.
The helipad site study in Chapter 4 identified five possi-
ble sites. The rooftop of the Main Hospital building on
Wing C is one of the proposed locations that was studied.
For the purposes of this study, the noise contour results
were based on locating the helipad at this site. The other
sites will be covered in a more detailed environmental re-
view at a later time.
The primary conclusion of the study is that there would
be an incidental noise increase in the general area of the
helipad from the proposed 1-3 daily operations. The
higher noise levels will be contained on the hospital cam-
pus within the immediate vicinity of the helipad. The
noise levels of individual overFlights may prove to be an
annoyance, but the impact will be minimal due to the
relatively low number of anticipated operations..
This chapter documents the field noise study, and de-
scribes the results. The noise criteria used to assess the
impact of the helipad is discussed in the first section. The
following two sections describe existing sound levels at
three sites in the community and their predicted sound
levels due to helicopter operations. The assessment of
noise impact is presented in the last section.
San Francesco General Hospital Air Medical Access Needs and Feasibility Study 6-1
CHAPTER B NOISE ANALYSIS
Gerson/Overstreet Arohitects e
NOISE IMPACT CRITERIA
Noise Measurement Methods
The noise impacts of helicopter operations can be based
on the cumulative noise exposure of multiple operations
over daily periods. The noise method that was utilized
was Day- Night Average Sound Level, or DNL, which is
the sum of daily sound exposure for a given period, or
the sound exposure level for a number of specific events
within a time period. This noise metric was based on so-
cial survey research that was conducted over the years
to quantify people's reaction to noise exposure levels in
the community. It divides 24 hours into two time periods:
7 AM to 10 PM is characterized as day and 10 PM to 7
AM is identified as nighttime hours. For events that oc-
curduring the nighttime hours, a night penalty of 10 dB is
added to take into account the greater sensitivity of peo-
ple to sounds that occur during these time periods. The
measurement unit of sound is the decibel, or dB Qust as
the unit to measure temperature is the degree or the unit
of length is the inch or foot).
Consider a car driving on a local street. Before the sound
of the car is heard there is already some sound that may
be heard in the area, called background or ambient
sound. This background sound may be due to distant
traffic, wind in the trees, people talking, etc. As the car
approaches the listener the sound due to the car can first
be heard just above the background sound, and then the
sound of the car increases as the car gets closer. As the
car passes the listener the sound reaches its highest
level; this level is called the maximum sound level. The
sound level than decreases and fades into the back-
ground sound level as the car drives farther away. This
maximum sound level will depend on several factors
such as the type of car (some cars are louder than oth-
ers), the speed of the car (higher speed causes higher
maximum sound levels), and the distance between the
car and the distance (the maximum sound is lowered if
the listener moves farther away from the street).
In a similar manner the maximum sound level of a heli-
copter when it is flying overhead represents the highest
sound level that will be heard during the flyover. This
level will also depend oh the type of helicopter, the speed
San Francisco General Nospita( Air Medico! Access Needs and Fecsi6i71ty Study 6- 2
NOISE ,ANALYSIS
Gerson/Overstreet Architectss
and type of operation (approach, departure, or level flyo-
ver), and the distance between the helicopter and the lis-
tener. Often it is not possible to measure the noise level
of the helicopter because it is below the level of the
background noise. However, it is possible to identify the
sound as belonging to a helicopter since it has a distinct
noise signature.
DNL as a background measure is a cumulative noise
measure based on an average of all the sounds occur-
ring during a typical 24-hour period. DNL was originally
developed by the federal government as a measure of
land use compatibility and is used in every state in the
Union with the exception of California. The cities and
counties of California typically use Community Noise
Equivalent Level (CNEL), which like DNL is very useful
for making land use planning decisions. Both measures
are almost identical. The distinguishing feature is that
CNEL divides the 24-hour period into three time periods
thereby adding a weighting factor of 5 d6 for events oc-
curring in the evening hours (defined as betweeh 7 PM to
10 PM). Both noise exposure methods contain a 10 d6
correction factor applied to nighttime sounds levels to ac-
count for increase annoyance during the night hours.
The day-night sound level was introduced as a simple
method for predicting the effects on a population of the
average long-term exposure to environmental noise. It
can be derived directly from an A-weighted sound expo-
sure level.
DNL was chosen for this report because, the City and
County of San Francisco use this. noise measure in their
Land Use Compatibility Chart for Community Noise found
in the General Plan. The Planning Department uses this
as a guideline for new development and for the assess-
ment of land uses. Research over the years has estab-
lished criteria which relate the acceptability of various
noise environments in terms of the DNL level to different
land uses (see Table 6-1-Land Use Compatibility Chart).
San Francisco General Hospito( Air Medico! Access Needs and Feasibility Study 6- 3
CHAPTER6 NoISEANAwsls Gerson/OverstreetArchitectss
Table 6-1
LAND USE COMPATIBILITY CHART FOR COMMUNITY NOISE
Scued lnveia M/d land ltm Cmsequmom~
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;i;j~m Satlsfaclmy, wiNwapeolalmim huulation ieWh'emeats.
New eamhaetim ar development abouht M undertiikon wllP aftc
• ebtailed malysls of the noise reduetlan rego'oentmu L made
d
a
needed neim iRmlation featmq included is the deaf.
New eaasereeelm or dwelopment aheNd 6enaraQy bo dixauraged.
~~ 6 aew crostieetiee w deY<lopmem. does proceed, a detailed aoayzit
rt a! the mue redmtlen renNrements mvat Ue made am eedW none
buWardm raawes halutled to the deedldn.
® New cmuWCLOOm deeNgmeneahould geoerapy net Bn,maet4ten.
The FAA uses an alternate cumulative noise measure,
the 24-hour equivalent sound level, Leq. The 24-hour
Leq is also an average of all the sounds occurring during
a full day, but without any weighting factors for time peri-
ods. This measure was used to analyze the everyday
occurring background noise in the neighborhoods adja-
cent to SFGH.
DNL can be measured with a special type of sound level
meter called an integrated sound level meter; a meas-
urement period of at least 24 hours is required. Alter-
nately, DNL due to a particular sound source such as
helicopter can be calculated from measurements or esti-
mates of the sound exposure levels (SEL) of individual
operations if the number and time of such operations dur-
ing a 24-hour period are known.
San Francisco General Hospital Air Medical Access Needs and Feasibility Study 6- 4
Cr(aarER6 NoisEANUrsis GersorVOverstree[Architecise
IrnpaCt Crlterla
It is useful to consider the sound levels that are routinely
experienced in the community which is in the vicinity of
the proposed helipad. For example, the maximum sound
level from a typical passenger car abouY50 ftaway trav-
eling on a local street at 35 mph is 60 to 70 dBA. Under
the same conditions the maximum sound level of a bus
or truck is between 78 and 90 dBA. The noise level of a
leaf blower can be between 80 and 95 dBA. All of these
everyday noise events and more are potential noise
sources which when measured over a 24-hour period
comprise the typical background noise level. It is against
this tapestry of sound levels that the helicopter noise
event is compared.
Land use compatibility guidelines have been established
by several federal agencies and many cities and counties
in California and are usually found in their General Plan
Noise or Land Use Elements. These compatibility guide-
lines typically show that residential land use is incompati-
ble with a CNEUDNL higher than 65 dB. This agrees
with the recommendations in the City of San Francisco's
Land Use Compatibility Chart. Hospitals or nursing
homes are acceptable within DNL levels of 65 dB.
Commercial and office buildings can exist within DNL
noise contours of 70 to 80 dB.
EXISTING SOUND LEVELS
Traffic is the dominant source of noise in the area around
the proposed helipad, particularly near the Highway 101
freeway and in the vicinity of major streets such as Po-
trero and Vermont Avenues. The background noise was
measured in 24-hour DNL and Leq at 3 different sites as
noted in Figure 6-1. Site 1 was on Potrero Ave. The sec-
ond site was in a residential area to the south of SFGH
on San Bruno. The third site was in the Potrero Hill Dis-
trict where the background noise levels were dominated
by Highway 101 traffic. A detailed discussion of the field
noise measurement study is found in Appendix D.
San Francisco's transit agency, MUNI, operates four dif-
ferent bus lines in the vicinity of SFGH, with two running
along Potrero Ave. (see Figure 6-2). In addition to the
MUNI routes, there is moderate to heavy car and truck
San Francisco Genera! Hospital Air Medico! Access Needs and Feasibility Study 6- 5
FIGURE 6-1
NOISE MONITORING
LOCATIONS
CHAPTER6 NOISE ANALYSIS Gerson/OVBrStreBf ArCf7lreCtS6
`' ~ ~, H = ) £ traffic along Potrero Ave. and moderate traffic on the side
sr r) ius ~ ) streets near SFGH. Highway 101 located directly to the
a ~ moo) )sT.,,, east of the hospital and contributes to the existing noise
~ ~ '' g) ~) ~ ' environment.
)T. _' SF N ~ q N) S)
~_ °~`os° ~` 4~ ~1 of ~ As was noted during the field noise measurement phase
~ sT. an,+o~y~ -1y ;_-",Sd`l~ ~ of the project, the overall noise level environment is
~ra~ ) ~r~ ' 1 1'wa
1;,~, { II I A dominated by transportation noise from buses, cars and
,,sarH). ~+ 0 1 )~I) ~ trucks. The measured noise levels for the background
') a ~ y I )) I) =~ ambient noise are summarized in Table 6-2. The DNL
! ( `' ~ ~ 9~ )~i n'~µ noise results range from 68 dB DNL for Site 1 (Potrero
~°"I I ~1~ ~x2"~ Ave.); 65 d6 DNL for Sipe 2 (San Bruno); and, 65 dB DNL
1 , o " for Site 3 (DeHaro at 24 St.).
FIGURE 6-2 Table 6-2
MUNI ROUTES NOISE MONITORING AROUND
SAN FRANCISCO GENERAL HOSPITAL
Location Measured
Comments
DNL (dB)
The noise environment was
dominated by local traffic (cars
#1 and light trucks) on 22"d Street
22nd St
be- and traffic on Potrero Avenue.
.
tween Potrero 68 In addition, pedestrians and oc-
and Hampshire casional airplane and helicopter
flyovers made some contribu-
tion to the overall noise envi-
ronment.
The noise environment was
dominated by traffic (cars and
light trucks) on 23rd Street and
San Bruno Avenue. Most of the
~ traffic was due to the parking
San Bruno 65 structure located across the
Ave. at 23rd St street and' general hospital cir-
culation. In addition, pedestri-
ans and occasional airplane
and helicopter flyovers made
some contribution to the overall
noise environment.
#3 Background noise is controlled
DeHaro at 24`n 6~ by US Highway 101 and punc-
St. tuated with occasional local traf-
ficand aircraft fl avers.
San Francisco Genera( Hospital Air Medical Access Needs and Feasibif7ty Study 6- 6
CHAPTER6 NoisEANAwsis ~ Gerson/OverstreetArchitectse
FIGURE 6-0
Figure 6-3
PROPOSED FLIGHT PATHS
Figure 6-3 shows the recommended planned flight tracks
for departure and arrival operations at the proposed roof-
top helipad. There is a flight path to the north over the
campus and towards the freeways and a flight path to the
south over 23rd. Street and the hospital parking structure.
These flight paths were selected to avoid residential ar-
eas and overfly major roads as much as possible in order
to minimize noise exposure. The choice of which flight
path to use for this rooftop location or any helipad site
depends upon: 1] the speed and direction the predomi-
nant wind is coming from; and, 2] where helicopter is
coming or going from a scene accident or hospital trans-
fer. Because the wind in this area typically comes from
the west/northwest, the primary flight path, predicted to
be used 85 percent of the time, will be an approach from
the south with the departure in a northerly direction.
When the wind is blowing out of the south/southwest, ap-
proximately 15% of the time during the year, the secon-
dary flight path will be an approach from the north with
the departure to the south.
The helicopter approach and departure angle to a rooftop
helipad is usually steeper than for a ground level helipad.
This is a benefit because the helicopter is at a higher alti-
tude for a longer period of time, thereby reducing the
noise exposure. The landing and takeoff profile for each
helicopter depends upon the their individual performance
capabilities, weather conditions, and the passenger load
or weight factor, among other variables.
The twin-engine helicopter that will operate at SFGH will
typically approach or depart the helipad at an angle rang-
ing from10 to 16 degrees. This translates into a slope of
6 to 1 for a 10-degree approach to 3 to 1 for a 16 degree
departure. That is, for every 6 ft traveled in a horizontal
direction the slope increases by 1 ft. Thus a 3 to 1
departure glide slope is steeper than a 6 to 1 slope. All
of the identified helicopters are capable of performing
these noise abatement type approach/departure glide
slope profiles.
San Francisco Genera! Nospita! Air Medical Access Needs and Feasibility Study ~ 6- 7
CHnwrER6 NoiseAHALrsis Gerson/OverstreetArchitectss
HELICOPTER MODELS
The primary helicopter emergency medical services
(HEMS) in the Bay Area are REACH, CALSTAR and Life
Flight. The helicopters owned by these providers will be
the ones that most often land at SFGH. The public heli-
copter providers such as the CHP, with a smaller helicop-
ter, will land on a much less frequent basis. Each pro-
vider uses a different model aircraft that is especially con-
figured on the inside for EMS missions. All private HEMS
providers own twin-engine turbine powered helicopters.
The noise contours were based upon these helicopters.
HELIPAD NOISE PREDICTIONS
Various helicopters may land at the helipad but those
owned by the Bay Area providers will land most often. In
order to predict the noise levels for impact evaluation
purposes and to provide conservative noise predictions,
a composite helicopter noise model was developed com-
bining the sound exposure levels (SEL) of the four differ-
ent helicopters weighted by their proposed usage of the
SFGH helipad. Table 6-3 identifies the helicopters and
contains the proposed percentage of use. The following
contains a discussion of the assumptions used for the
noise analysis.
TABLE 6.3 HELICOPTER USAGE
Helicopter Type Percentage Use
Agusta 109A 40%
BO 105 40%
Be11 222A 10%
BK 117 10%
Helioad Noise Analysis
The helicopters in Table 6-3 were assumed for all opera-
tions. The FAA approved computer program called, Inte-
grated Noise Model (INM), contains a fixed data base of
helicopter noise levels. The sound levels in this data
base are derived from helicopter noise certification data.
San Francisco Genera! Hospital Air Medico( Access Needs and Feasibility Study 6- 8
CHAPTER6 NoisEAwu.vsis Gerson/OverstreetArohdectss
That is, each helicopter manufacturer must meet a cer-
tain FAA noise certification standard before they can sell
a civil helicopter that is used in the United States. INM is
the program that was used to generate the noise con-
tours around the helipad. However, it does not have the
ability to account for the real-life noise abatement proce-
dures that the pilots can use to help reduce the noise
levels. A helicopter noise level composite was created by
weighting the sound exposure levels in INM with the per-
centage of time over a year that the helicopters might
land at the SFGH helipad.
Since there is no helipad at SFGH, there is no flight op-
erations history. Therefore it was decided tq predict flight
operations history far SFGH based upon a careful survey
of the other Bay Area regiohal hospitals of similar size
with helipads (see Appendix B).
In an effort to take a conservative look at the impact of
the helicopter operations, it was decided to look at the
noise exposure far two different idealized days: 1] the
average day of 1 flight (takeoff and a landing); and, 2] the
busy day with 3 flights (3 takeoffs and 3 landings). These
scenarios will present a worse case picture of the noise
exposure at the proposed rooftop site. Two noise con-
tours were generated to depict these flight operation sce-
narios.
The following are the assumptions used in the INM model
calculations.
1] The composite helicopter noise model is based
upon the usage weighted helicopter noise expo-
- sure levels ($EL).
2] The average, normal day is 1 flight at night after
10 PM. Therefore, a 10 dB penalty is added to the
composite noise level.
3] The busy day is 3 flights: 2 flights between 7 AM
and 10 PM; 1 flight between 10 PM and 7 AM.
Again, a 10 dB penalty was added to the compos-
ite noise levels for a nighttime landing.
4] The angle of the glide slope was 10 degrees or a
slope of 6 to 1.
San Francisco General Hospital Air Medical Access Needs and Feosibility Study ~ 6- 9
CHAPTER6 NoisEANALYSis Gerson/OverstreetArchitectss
The analysis was performed using INM Version 6.Oc.
This program calculates contour values in terms of Day-
Night Average Sound Level (DNL).
NOISE IMPACT ASSESSMENT
The contour value of 65 dB DNL was calculated for both
the average- and the busy day. The INM calculations
were based upon the flight path depicted in Figure 6-4.
As can be seen in the aerial, the approach flight path
from the south would fly over the parking structure in a
northerly direction.
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PROPOSED ROOFTOP HELIPAD
WINGC(Site 1) Figure 6-4
AVERAGE DAY-DNL COMOURS
MEIILGPiER NIGHRIME IAN(NNp(I F6fIN
Figure 6-4 -shows one operation and a contour that is
almost entirely on the hospital property even though this
was for a nighttime operation which by definition in the
DNL methodology includes a 10 dB penalty. The higher
San Francisco Genera! Hospital Air Medical Access Needs and Feasibility Study 6- 10
CHAPTERS NoisEANrwsis - GersorVOverstrreetArohitectse
noise levels will be in closer proximity to the main hospi-
tal building. If the DNL contour was calculated fora sin-
gle daytime event, the contour would be smaller and en-
tirely within the hospital campus.
Any residential dwellings along 23ro Street are outside the
65 dB DNL contour generated by the helicopter landing
profile. According to the background noise study, the
ambient noise on San Bruno Street just south of 23'~
Street was 65 dB DNL fora 24-hour period.
Figure 6-5, which is the Busy Day scenario - is an exam-
ple of a 65 dB DNL for 3 flights on a given day. This pre-
dicts the impact for 2 daytime and 1 nighttime operation.
This shows the impact for a worst case scenario should
there by 3 landings within a 24-hour period. This noise
exposure contour is larger because of the increase in the
number of operations. The 65 d8 contour extends to the
south of 23'~ Street. The noise impact on the busi-
ness/residential buildings on 23`d Street adjacent to the
hospital property will be heard for a few seconds per
flight. The 65 dB DNL contour does not extend across
Potre~o Ave. to the Mission District nor east to the Po-
trero Hill area.
HELICOPTER NOISE ABATEMENT OPTIONS
The two scenarios depicted above did not include possi-
ble noise reduction procedures that pilots could employ
when utilizing a "fly neighborly' approach. This is the
procedure that the pilots who fly for EMS providers em-
ploy on a continuing basis when landing in urban area.
On Approach
The helicopter noise levels experienced on the ground
can be reduced 2 to 6 dB with a "fly neighborly" ap-
proach. The basic difference between a quieter ap-
proach technique and a normal one is that the pilot be-
gins the descent to the helipad before reducing the air
speed. The rate of descent is between 600 to 800 fpm.
The quieter technique uses a glide slope that is a few
degrees steeper.
San Francisco General Hospital Air Medical Access Needs and Feasibility Study 6- 11
NOISE ANALYSIS
sm sr _~
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Gerson/Overstreet Architecfss
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PROPOSED ROOFTOP HELIPAO
WING C (Ske 1) Fig. 6-5
BUSY OAY-0NL CONTOURS
HELICOPTER LANGINGS [! FlIgNS) -
On Departure
Contrary to popular belief, takeoffs are reasonably quiet
operations. The total ground area exposed to helicopter
noise can be reduced 6y using a high rate of climb and
making a smooth transition to forward flight. Given
weather conditions and desired direction of departure,
the pilot should avoid overFlying noise sensitive areas
where possible.
The noise abatement options were not utilized in the cal-
culations of the noise contours because a more conser-
vative result was desired, However, the pilots would be
expected to use them as a noise abatement mitigation
measure during actual operations.
San Francisco General Nospita( Air Medico! Access Needs and Feasibility Study 6- 12
CHAPTER E NOISE ANALYSIS
Gerson/Overstreet Archdects s
CONCLUSION
This preliminary study, based upon helicopter noise certi-
fication sound levels and computer generated noise con-
tours, is a first attempt to characterize the noise impact
that might be experienced in the community due to heli-
copter operations. As a result, the two conservative sce-
narios that were developed showed minimal impact on
the surrounding community when using a land use as-
sessment criteria.
A further study is recommended in which actual helicop-
ter flyovers are measured at various sites in the commu-
nity. This would provide a more accurate assessment of
the length of time for the noise event and the impact of
the noise exposure. Ideally, this would be carried out as
part of the project's environmental review process.
San Francisco Genera! Hospital Air Medical Access Needs and Feasibility Study 6- 13
Noise and Noise Complaints: Helicopter Noise Page 1 of 2
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Background
Responsibilities
How We Measure
and Assesslts
Impact
Frequently Asked ~-rcraft operate in three scenarios: taking off From a ruhway or.he]
Questions ~ approaching a runway or a helipad, and enroute. When aircraft
both
LodgeaNoise ,
and helicopters, are either taking off or landing
there are no
i
i
Complaint
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altitude requirements. When enroute, fixed wing aircraft must maintz
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Airspace Redesign
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Newsletterl
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Maps ground. In areas where airspace is congested, and the FAA has specii
Pre-Scoping or altitudes desi ned to se arate aircraft helico ter
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Summary Report those prescribed routes or altitudes.
Airspace Redesign
WetSiie Helicopterstypical ly operate at speeds slower than fixed wing airc~
ICAO Noise News with a greater ability to turn and hover. Helicopters must generall}
EU-US Dispute Over flow of fixed wing aircraft. Helicopters must operate clear of clou<
Hushkits speeds allowing adequate opportunity to see other air traffic or obr
DOT Noise in time to avoid collisions. As with highway vehicles, the person p~
Abatement Policy responsible for the safe operation of the aircraft is its o
erat
2000 p
or,
Topicallndex: You may want to contact the Eastern Region Helicopter Council (ERHC)
260"Turn Rose Hollow Drive, Yardley, PA 19067, (845)353-6050, enc~nvc@aol. con
Helicopter Noise helicopter noise. The ERHC is a voluntary member organization compri
-----~- regional helicopter pilots that meet regularly and publish a quarter
Additional Noise newsletter. They have a "Fly Neighborly Program" and are interested
Links: feedback about helicopter overflights. Given enough specific informz
Office Of ma be able to identif
Environment & I' Y the helicopter operator flying in your area.
Energy
Fed.lnteragency
Committee On
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JFK International
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LaGuardia Airport
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Evaluate Aircraft
Routing Strategies -
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a e?
For further information, please contact:
Federal Aviation Administration
Eastern Region
1 Aviation Plaza
Jamaica, NY 11434-4809
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Noise and Noise Complaints: Helicopter Noise
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Eastern Region Home I
How We Measure and Assess Its Impact
NOISE -UNWANTED SOUND
Noise is usually regarded as unwanted sound -sound that disturbs our routine activi
peace and quiet, and perhaps causes a feeling of annoyance. Which sounds are NOI;
obvious to each listener, and he or she has no need to measure it. It's there, and it's
bothersome.
But those who work to abate noise, to minimize its effects, or to develop quieter vehi~
need to measure noise. And that is not an easy task. Consider sounds typical of a su
neighborhood on a "quiet" afternoon. If a short time history of those sounds is plotte
graph, it would look very much like Fic`~ure 1.
The sound levels are plotted in units of A-weighted decibels (abbreviated dB, or some
dBA}, a logarithmic measure of the magnitude of a sound as the average person hear
"A-weighting" accounts for the fact that humans do not hear low frequencies and hig
frequencies as well as they hear middle frequencies, and it corrects for the relative e1
of the human ear at the different frequencies. A logarithmic measure is used in order
efficiently the wide range of sound magnitudes encountered daily.
In this example, the background, or residual sound level in the absence of any identii
noise sources, is about 45 db. During roughly three-quarters of the time, the sound le
dB or less. The highest sound level, caused by a nearby motorcycle, is 73 d6, while a
generates a maximum sound level of about 68 dB. The question then becomes: how i
"measure" this variable community noise?
MAXIMUM SOUND LEVEL
One obvious way of describing this sound environment is to measure the maximum '
level - in this case, the nearby motorcycle at 73 dB: But the aircraft sound, although r
loud as the motorcycle, lasts longer. Studies have shown that human response to no
involves both the maximum level and its duration, so the maximum sound level alone
sufficient to evaluate the effect of noise on people.
SOUND EXPOSURE LEVEL
A second way of describing this sound environment is to measure the sound exposu
(abbreviated SELL, which is the total sound energy of a single sound event and takes
account both its intensity and duration. One way to under-stand SEI, is to think of it a
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Noise and Noise Complaints: How We Measure and Assess Impact Page 2 of 4
sound level you would experience if all of the sound energy of a sound event occurre
second. This normalization to a duration of one second allows the direct comparison
sounds of different durations. In the sample time history in Fioure 1, the motorcycle c
an SEL of about 77 d8, while the aircraft generates an SEL of about 81 dB.
EQUIVALENT SOUND LEVEL
The maximum sound levels and sound exposure levels measure individual sound ew
may occur only once, or may occur several times during the day in our neighborhooc
number of times, these events occur is also important in measuring the noise enviroi
One way to describe this factor might be to count the number of events per day for w
SELs exceed 80 dB, plus the number which exceed 75 dB, plus the number which ex~
d6, and so on. A more efficient way to describe both the number of such events and
sound exposure level of each is the time-average of the total sound energy over a spy
period, referred to as the equivalent sound level (symbolized Leq). In the example shy
Figure 1, the time-average sound level is roughly 56 dB. This accounts for all of the s
energy during the sample period, and provides asingle-number descriptor in terms c
energy per second.
DAY-NIGHT AVERAGE SOUND LEVEL
One additional factor is also important in "measuring" a sound environment - the occ
of sound events during nighttime. People are normally more sensitive to intrusive so
events at night, and the background sound levels are normally lower at night because
decreased human activity. Therefore a "penalty" may be added to sound levels whicl
during night hours, to include these factors. By convention, a 10 dB penalty is added
levels occurring between 10:00 p.m. and 7:00 a.m. the following morning. The 24-hou
sound level, including this 1D dB penalty, is known as the day-night average sound le
(abbreviated DNL), This 10 dB penalty means that one nighttime sound event is equip
10 daytime events of the same level.
COMMUNITY ANNOYANCE
Annoyance is a summary measure of the general, adverse reactions of people to noi;
disrupt their daily activities telephone conversations, TVlradio listening, sleep, or sin
tranquility. Currently, the best measure of this reaction is the percentage of people w
characterize themselves as :'highly annoyed" by long-term exposure to their noise
environments.
Extensive research has found khat day-night average sound level correlates very well
community annoyance from most environmental noise sources. Fioure 2 summarize:
relationship between DNL and percentage of people who said they were highly annoy
transportation noise, based on 453 surveys conducted worldwide. Some of these stu
found that communities report themselves slightly more annoyed by aircraft noise th
surface transportation noises.
NOISE COMPATIBILITY GUIDELINES
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Noise and Noise Complaints: How We Measure and Assess Impact Page 3 of 4
r
Using this research, federal agencies have adopted certain guidelines for compatible
uses and environmental sound levels. Land use is normally determined by property ~
such as residential, industrial, or commercial. Noise levels that are unacceptable for I
may be quite acceptable for stores or factories. The Federal Aviation Administration I
issued these guidelines as part of its Airport Noise Compatibility Program, found in F
of the Federal Aviation Regulations.
In general, most land uses are considered to be compatible with DNLs that do not ex~
dB, although Part 150 declares that "acceptable" sound levels should be subjedt to Ic
conditions and community decisions. Nevertheless, a DNL of 65 d6 is generally idenl
the threshold level of aviation noise, and other sources of community noise, which ai
"significant".
In adopting a threshold criterion for noise impact, we must keep several important fay
mind. First, aday-night average sound level below 65 dB does not mean that no one i
annoyed by that level of noise from transportation sources. To the contrary, as show
Figure 2, about 12 percent of people living with a DNL of 65 dB report themselves to I
"highly annoyed". About 3 percent are highly annoyed at a DNL of 55 d6. This is
understandable, because the same research on noise effects has found that the phys
amount of noise is only one element in feelings of annoyance with environmental not
Activities which may be disrupted by noise events (study, conversation, listening to i
watching TV, solitude, etc.): beliefs that such noise could be better controlled; attitud
toward the noise maker, ahd personal fears regaMing the source of the noise, are all
important factors in people's perception of annoyance. Additionally, a small percents
people are simply more sensitive to noise than most other people, while a small perc
are little annoyed even at high noise levels. The combination of these factors causes
people to interpret sounds as "unwanted" noise in different ways. A measure of noise
such as day-night average sound level, provides a reliable indicator of overall commi
response, but does not tell how any single individual 11 respond.
As a result there is probably no minimum level of transportation noise at which no or
annoyed. General guidelines for noise compatibility identify day-night average sound
between 55 and 65 dB as "moderate exposure" and as generally acceptable for reside
use. Above a DNL of 65 d6, these guidelines identify the noise impact as "significant'
this designation is currently a factor in decisions to provide federal funds for mitigate
projects.
Because DNL combines both the intensity and number of single noise events (along
nighttime weighting), it also is not a good estimator of the single-event sound levels
experienced. For example, a DNL of 65 dB may be generated by any of the following
combinations of average sound exposure level and the effective number of those eve
where "effective" number is the sum of the number of daytime events plus 10 times tl
number of nighttime events:.
Average
SEL Effective
Number of Events DNL
87.4 dB 500 65 d6
94.4 d8 100 65 dB
97.4 dB 50 65 d6
Consider two communities: one near a large airport, the other near a small one. Both
exposed to a DNI, of 65 dB. Although people near the small airport experience only 51
operations in a day, the average SEL of each of these is about 97 dB. On the other ha
community near the large airport is impacted by 500 daily operations, but each of the
an average SEL of about 87 d6. This does not invalidate the usefulness of the DNL m
but should be considered, for example, in determining needs for structural sound ins
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Noise and Noise Complaints: How We Measure and Assess Impact
Page 4 of 4
Some criticism of DNL• stems from beliefs that the levels identified with land-use com
are too high, Any compatibility guideline, such as a DNL of 65 dB, must represent a b
between that level which is most desirable to protect communities and that which cai
achieved with cost-effective mitigation measures and available technology. There is i
criterion which can fit all airports and all communities. Local communities may choo;
mitigate impacts below a DNL of 65 dB.
SUPPLEMENTAL MEASURES
A time-average measure of noise impact, such as day-night average sound level, is a
criticized because people feel that they are annoyed by individual sound events, rath
some "fictitious" average level. Clearly, people are bothered by individual noise even
their sense of annoyance increases with the number of those noise events, and those
occur late at night.
DNL provides a combined "measure" of these factors which can be used to evaluate
and predicted future conditions on an unambiguous, single-number basis. Other men
such as maximum sound level, or sound exposure level, give valuable supplemental
information in analyzing airport noise. For example, as noted above, in designing soy
insulation for dwellings and schools, single-event measures are necessary. Neverthe
day-night average sound level remains the best single measure for assessing the eff~
airport noise on communities, and allows a standardized and effective means forme.
transportation noise.
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Noise and Noise Complaints: Responsibilities Page
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Press Release: Rep. Nadler Introduces Helicopter Noise and Safety Act Page 1 of 2
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FOR IMMEDIATE RELEASE Contact: Joel B. Finkelstein
February 9, 1999 202.225.5635
REP. NADLER ANNOUNCES INTRODUCTION OF
"HELICOPTER NOISE CONTROL AND SAFETY ACT"
Bill Will Empower FAA to Address Loud and Hazardous Helicopter
Operations
WASHINGTON, DC -- U.S. Representative Jerrold Nadler (D -Manhattan
and Brooklyn) today joined with Rep. Carolyn Maloney (D -Manhattan and
Queens) to announce the introduction of the "Helicopter Noise Control and
Safety Act." The bill, which would empower the Federal Aviation
Administration (FAA) to protect the public from hazardous and disturbing
helicopter operations, could have a significant effect on New York City skies.
"City residents deserve the right to recapture some measure of the peace and
tranquility that has been taken away from them by constant helicopter
activity," Rep. Nadler said. "In addition, helicopter safety in urban areas is an
issue that must be addressed."
The bill is crafted to deal with risks that helicopter operations pose to public
health and welfare in densely populated azeas -- including New York City. If
the bill is adopted, the Administrator of the FAA would be empowered to act
on issues relating to the effects of helicopter activity in cities. Currently, the
FAA does not have the ability to address directly risks that helicopters pose in
urban areas.
"Not too many people are going to azgue that stopping the constant helicopter
traffic is going to make New York City sound like Martha's Vineyard," Nadler
said. "Yes, New York is loud and buzzing with life -- and few of us would
have it any other way. But there is a very real difference between the sounds
of the life of New York and a public nuisance that directly attacks New York's
quality of life."
"Constant helicopter noise isn't part of the deal that New Yorkers have agreed
to for living in the most vibrant city in the world," Rep. Nadler said.
Representative Nadler has served in Congress since 1992. He represents the
8th District of New York, which includes parts of Manhattan and Brooklyn.
http://www.house.gov/nadler/29heli.htm 5/29/2003
Press Release: Rep. Nadler Introduces Helicopter Noise and Safety Act Page 2 of 2
###
http://www.house.gov/nadler/29heli.htm 5/29/2003
FAA -Section 747
Page I of 1
Office of Environment
and Energy (AEE)
FAA Home Noise Division (AEE-100)
AEE
AEE-100
section ~a~ H.R.1000 • Wendell H. Ford Aviation Investment and Reform Act for the 21st Century (E
So na~ Noisera 55 Section 747. Nonmilitary Helicopter Naise
Helicopters
Related News & Congressional Mandate
Inrormation
1+~~~« Executive Summary:
.~,..
In response to public concerns about military helicopter noise impact on densely populated c
)(';° the US Congress outlined issues for the Federal Aviation Administration (FAA} to investigate
~' recommendations on reducing helicopter noise effects.
~~~' " The,result was the following legislative guidance developed and specified in the FAA authori:
entitled, "H.R.1000 -Wendell H. Ford Aviation Investment and Reform Act for the 21St Centw
~+~.°'' Section 747. -Nonmilitary Helicopter Noise. It states:
' Section 747. -Nonmilitary Helicopter Noise
a. IN GENERAL -The Department of Transportation (DOT) Secretary shall conduct a stt
the effects of nonmilitary helicopter noise on individuals in densely populated areas in
continental United States; and (2) to develop recommendations for the reduction of the
nonmilitary helicopter noise.
b. FOCUS - !n conducting the study, the DOT Secretary shall focus on air fraffic control F
address helicopter noise problems and shat! fake into account the needs of law enforc
c. CONSIDERATION OF 1/lEWS - !n conducting the study, the DOT Secretary shall con.
views of represehtatives of the helicopter industry and organizations with an interest it
nonmilitary helicopter noise.
d. REPORT -Not later than one year after the date of the enactment of this Act, the DO7
shall transmit to Congress a report on the results of the study conducted under this se
Based on this guidance, the FAA's Office of Environment and Energy (AEE-100) has outlinec
study approach that addresses the issues prescribed. Go to "FAA Study Process" to see sct
elements.
htlp://www.aee.faa.gov/Noise/Section 747_Congressional_Mandate.htm 5/29/2003
Effects of Aviation Noise on Awakenings from Sleep
~~~ ~,x .a,~ !Y'~pr~t"~i,~z z,~F. a, -;a. ,~ vz '~~ltii~ s~iF ~,. ,,,. a_'~ - .w;a
About RCAII Aetirkles Raearclt Pu6lkatieroa: News Mows ]rdfa
Effects of Aviation Noise on Awakenings from
Sleep
Federal Interagency Committee on Aviation Noise.
(FICAN)
June 1997
The effect of aviation noise on sleep is along-recognized concern of
those interested in addressing the impacts of noise on people. In
1992, the Federal Interagency Committee on Noise (FICON)
recommended an interim dose-response curve to predict the percent
of the exposed population expected to be awakened as a function of
the exposure to single event noise levels expressed in terms of SEL.
Since the adoption of FICON's interim curve in 1992, substantial field
research in the area of sleep disturbance has been completed. The
data from these studies show a consistent pattern, with considerably
less percent of the exposed population expected to be behaviorally
awakened than had been shown with laboratory studies.
FICAN recommends the adoption of a new dose-response curve for
predicting awakening, based on the field data described in this paper
and supporting references. The Committee takes the conservative
position that, because the adopted curve represents the upper limit
of the data presented, it should be interpreted as predicting the
"maximum percent of the exposed population expected to be
behaviorally awakened", or the "maximum % awakened".
1. SUMMARY
The effect of aviation noise on sleep is along-recognized concern of
those interested in addressing the impacts of noise on people.
Historical studies of sleep disturbance were conducted mainly in
laboratories, using various indicators of response
(electroencephalographic recordings, verbal response, button push,
etc). Field studies also were conducted, in which subjects were
exposed to noise in their own homes, using real or simulated noise.
However, in a 1989 assessment of existing research, Pearsons
indicated the need for substantially more work in this area, citing the
large discrepancy between laboratory and field studies as a major
concern.
In 1992, the Federal Interagency Committee on Noise (FICON)
recommended an interim dose-response curve to predict the percent
of the exposed population expected to be awakened (% awakening)
as a function of the exposure to single event noise levels expressed
in terms of sound exposure level (SEL). This interim curve was
based on the data presented in the 1989 study. The FICON report
also recommended continued research into community reactions to
aircraft noise, including sleep disturbance.
Since the adoption of FICON's interim curve in 1992, substantial field
research in the area of sleep disturbance has been completed, using
Page 1 of 8
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Effects of Aviation Noise on Awakenings from Sleep Page 2 of 8
a variety of test methods, and in a number of locations. The data
from these studies show a consistent pattern, with considerably less
percent of the exposed population expected to be behaviorally
awakened than had been shown with laboratory studies.
In light of this new information, FICAN recommends the adoption of
anew dose-response curve for predicting awakening, based on the
field data described in this paper and supporting references. The
Committee takes the conservative position that, because the
adopted curve represents the upper limit of the data presented, it
should be interpreted as predicting the "maximum percent of the
exposed population expected to be behaviorally awakened", or the
"maximum % awakened". FICAN cautions that the dose-response
relationship presented here relies on behavioral awakening as the
indicator of sleep disturbance; relationships between aircraft noise
and other potential sleep disturbance or related health effects
responses have not been established by any of these newer studies.
FICAN further notes that this curve should be applied only to long-
term residential settings and should not be generalized to include
children.
The new finding on the relationship between aircraft noise and sleep
disturbance does not call into question the nighttime penalty applied
to Day Night Sound Level (DNL). The 10 d6 penalty added to noise
levels for the period 10 p.m. to 7 a.m. is intended to account far the
increased intrusiveness of noise at night. The ambient is generally
lower and more people are at home during this period than at other
times of the day. Thus, the opportunities for activity interference are
much higher during nighttime which could lead to greater
annoyance.
Continuing efforts to identify other dose-response relationships are
being undertaken by standards-setting organizations, such as the
American National Standards Institute. FICAN will evaluate proposed
relationships developed by such groups as they are published; until
that time, FICAN recommends the use of the curve presented here
for assessing potential sleep disturbance caused by aircraft noise.
2. Background
2.1 The Nature of Sleep Disturbance
The effect of aviation noise on sleep is along-recognized concern of
those interested in addressing the impacts of noise on people.
Historical studies of sleep disturbance were conducted mainly in
laboratories, using various indicators of response
(electroencephalographic recordings, verbal response, button push,
etc). Field studies also were conducted, in which subjects were
exposed to noise in their own homes, using real or simulated
transportation noise Lukas, 1975; Griefahn and Muzet, 1978; and
Pearsons et al., 1989].
Based on a 1989 literature review by Pearsons for the U.S. Air
Force, no specific adverse health effects have been clearly
associated with sleep disturbance, characterized either by
awakening or by sleep-state changes Pearsons, 1989].
Nevertheless, sleep disturbance is deemed undesirable, and may be
considered an impact caused by noise exposure.
http://www.fican.org/pages/sleepdst.html 5/29/2003
Effects of Aviation Noise on Awakenings from Sleep
2.2 Methodological Considerations
Sleep disturbance studies have employed a variety of factors in
study design, sleep disturbance measurement, and noise exposure
assessment. Differences in these techniques can have influences on
the results of the studies, and a basic understanding of the
differences is important for interpreting the results.
Study Design: Laboratory vs. Field Research
The most important issue with regard to the design of sleep
disturbance studies has been the location of test subjects: as
demonstrated in the meta-analysis by Pearsons, there has been a
consistent, significant difference in the level of disturbance observed
between laboratory studies, in which subjects are exposed to noise
in a laboratory setting, and field studies, in which subjects are
exposed to noise (actual or simulated) in their own home. Generally,
laboratory studies have shown considerably more disturbance than
field studies Pearsons, 1995]. Finegold speculates that the
significantly greater awakening observed in the laboratory is due to
the lack of habituation Fine old, 1993].
Measures of Sleep Disturbance
Distinctions can be made between a variety of sleep disturbance
responses, which can be identified through different data collection
methods in sleep studies.
Behavioral awakenings typically are defined as awakening by the
subject enough to initiate a physical acknowledgment, such as
button-pushing or verbal response. Sleep disturbance also can be
defined as arousals or gross bodilymovemenf (motility), identified by
periods of actimetric response j1_), or by electroencephalographic
(EEG) response, which may or may not result in actual awakening.
Researchers are careful to point out that the relationship between
behaviorally-confrmed awakening and motility is not clear, though
both show clearly defined dose-response relationships.
In addition to the variety of measures for identifying disturbances
from individual events, most sleep disturbance studies collect data
from subjects concerning cumulative sleep effects. For example,
measurements can be made of the total sleep time and/or time to fall
asleep, and subjects can be questioned on sleep quality (feeling
upon arousal, etc.). Two major problems with collecting cumulative
data are the potential influences of disturbance caused by non-noise
sources, and the difficulty of avoiding bias in test subjects on self-
report.
Noise Metrics
Similarly, the noise metrics used to quantify noise exposure in sleep
research fall into two categories: (1) measures of individual events,
and (2) cumulative measures. Single event measures that have been
used in sleep disturbance studies include the Maximum A-weighted
Level (Lmax), Perceived Noise Level (PNL), Sound Exposure Level
(SEL), Effective Perceived Noise Level (EPNL), and C-Level (CL).
Cumulative measures are used to characterize the noise events over
an entire night or day, and have included the Equivalent Noise Level
(Leq), Composite Noise Level (CNL), Day-Night Average Sound
Level (DNL), Community Noise Equivalent Level (CNEL), and
Cumulative Distribution Levels or Percentile Levels, (Lx).
Page 3 of 8
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Effects of Aviation Noise on Awakenings from Sleep
A-weighted measures of single events have been most often used in
sleep disturbance studies, with either Lmax or SEL being used in
most of the recent studies, based on general consensus that single
event metrics are more useful far predicting sleep disturbance than
cumulative measures (2~.
2.3 FICON Sleep Disturbance Recommendations
In 1992, the Federal Interagency Committee on Noise (FICON)
recommended an interim dose-response curve to predict the percent
of the exposed population expected to be awakened (% awakening)
as a function of the exposure to single event noise levels expressed
in terms of the sound exposure level, SEL [FICON, 1992]. This
interim curve was based on statistical adjustment of Pearsons' 1989
analysis, and included data from both laboratory and field studies
Fine cld, 1993]. The recommended dose-response relationship is
shown in Fi ure 1, and can be expressed by the following equation:
Awakenings = 0.000007079 x SELs.aes
The FICON report also recommended continued research into
community reactions to aircraft noise, including sleep disturbance.
3. Recent Sleep Disturbance Research
Three recent studies have added considerably to the stock of data
on sleep disturbance caused by aviation noise. The first of these was
conducted in the United Kingdom in 1992; the second in the U.S.
near Castle Air Force Base and near Los Angeles International
Airport in California in 1992; and the most recent study was
conducted in communities near Stapleton International Airport (DEN)
and near Denver Intemational Airport (DIA) in Colorado, both before
and after the opening of DIA in 1995. These studies,are summarized
below.
3.1 U.K. Study
The United Kingdom's (U.K.'s) Civil Aviation Authority initiated a
study of aircraft noise and sleep disturbance in 1990 to assist the
U.K. Department of Transport in developing proposals for future
restrictions on nighttime aircraft operations at the London airports
Ollerhead et al., 1992]. In this field study, nearly 50,000 subject-
hours of sleep disturbance were collected at four airports, using both
activity meters (actimeters) and EEG to measure sleep disturbance
in test subjects. In total, 5,742 subject-nights of actimetry data and
178 subject-nights of sleep-EEG data were collected.
The major conclusions of the study are as follows:
• All subjective reactions to noise vary greatly from person to
person and from time to time and sleep disturbance is no
exception; deviations from the average can be very large.
Even so, this study indicates that, once asleep, very few
people living near airports are at risk of any substantial sleep
disturbance due to aircraft noise, even at the high event
levels.
. At outdoor event levels below 90 dBA SEL (80 dBA Lmax),
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Effects of Aviation Noise on Awakenings from Sleep
average sleep disturbance rates are unlikely to be affected by
aircraft noise. At higher levels, and mast of the events upon
which these conclusions are based were in the range 90 to
100 dBA SEL (80 to 95 dBA Lmax), the chance of the
average person being wakened is about 1 in 75. Compared
with the overall average of about 18 nightly awakenings, this
probability indicates that even large numbers of noisy
nighttime aircraft movements will cause very little increase in
the average persoh's nightly awakenings. Therefore, based
on expert opinion on the consequences of sleep disturbance,
the results of this study provide no evidence to suggest that
aircraft noise is likely to cause harmful after effects Ollerhead
et al., 1992].
Finally, the study emphasized that these are estimates of average
awakenings, and it acknowledges that some individuals in any
exposed population are likely to be more sensitive to nighttime noise,
while others will be less sensitive.
3.2 Los Angeles Study
The 1992 study conducted for the USAF Fidell et al., 1994]
observed the effects of nighttime noise exposure on the in-home
sleep of residents near Castle Air Force Base and near Las Angeles
International Airport and in several suburban control households with
negligible aircraft noise exposure. Test participants pressed a button
upon awakening far any reason, after retiring for the evening. A total
of 1,887 subject-nights of data were collected from 38 men and 47
women living in 45 different homes. Length of residence for the test
subjects ranged from two to more than 40 years. Major findings of
the study are as follows:
. A statistically reliable relationship was observed between
sound exposure levels of noise intrusions in sleeping quarters
and behaviorally confirmed awakenings within five minutes of
occurrence of noise intrusions.
• Although outdoor noise exposure level at the test sites varied
over the range of levels of principal interest far environmehtal
analysis purposes ll, the prevalence for awakening among
test participants did not increase greatly with sound exposure
levels of noise intrusions in sleeping quarters.
• Of a total of 4,452 awakening responses, only 326 could be
associated with noise events.
• The average spontaneous rate of behaviorally confirmed
awakenings among test participants at all sites was
approximately two per night. This figure did not differ
significantly across sites with varying levels of nighttime noise
exposure Fidell et al., 1994].
• The authors cautioned that the test subjects may not be
representative of all residential situations, and that
generalizatons of the data obtained in the study should be
limited to long term residents of areas with stable nighttime
noise exposure.
3.3 Denver Study
A large scale field study of noise-induced sleep disturbance was
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Effects of Aviation Noise on Awakenings from Sleep
conducted in the vicinities of Stapleton International Airport (DEN)
and Denver International Airport (DIA) in anticipation of the closure
of DEN and the opening of DIA. Both indoor and outdoor
measurements of aircraft and other nighttime noises were made
during four data collection periods. Measurements were made in 57
homes, over a total of 2,717 subject-nights of observations. Sleep
disturbance was measured by several methods, including button
pushes upon awakening and body movements, recorded by
actimeters.
Although average noise event levels measured outdoors decreased
significantly at sites near DEN after its closure and increased slightly
at sites near DIA after its opening, indoor noise levels varied much
less in homes near both airports. No large differences were
observed in noise-induced sleep disturbance at either airport, as
measured before and after the DIA opening. Indoor Sound Exposure
Levels of noise events were, however, closely related to and good
predictors of actimetrically defined motility and arousal.
The major findings of the Denver study are the following:
• The current findings closely resemble those of prior field
studies of noise-induced sleep disturbance.
• Outdoor nighttime Leq decreased about 12 dB on average at
DEN upon closure of the airport, but increased only about 3
dB at DIA after opening of the airport. Indoor nighttime Leq
varied little at either location with the transfer of flight
operations from DEN to DIA.
• The average number of behavioral awakenings per night was
1.8 at DEN and 1.5 at DIA. The number of spontaneous
awakening responses (unassociated with noise events) was
1.5 per night at DEN and 1.3 at DIA.
• Statistically reliable relationships were observed between
sound exposure levels of individual noise intrusions as
measured inside sleeping quarters and several measures of
sleep disturbance. Fidel! et al., 1995]
4. Recommended Revised Sleep Disturbance Relationship
FICAN has evaluated the data and conclusions of the three Feld
studies described in this paper: The combined data are presented in
Fiaure 2, along with data from six previous field studies [Pearsons,
1989]. The "FICAN 1997" curve shown in Figure 2 predicts a
conservative dose-response relationship for the combined Feld data.
The FICAN curve is also depicted, for comparison purposes; based
on the current field data, the dose-response relationship given by
this older curve significantly overestimates the extent of aircraft
noise-related awakenings for a given SEL exposure.
The FICAN 1997 curve represents the upper limit of the observed
field data, and should be interpreted as predicting the "maximum
percent of the exposed population expected to be behaviorally
awakened", or the "maximum % awakened" fora given residential
population. The central tendency of the recent data was not chosen
as the recommended curve because it could underestimate
awakenings for same situations or communities. FICAN cautions that
the dose-response relationship presented here relies on behavioral
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Effects of Aviation Noise on Awakenings from Sleep
awakening as the indicator of sleep disturbance; relationships
between aircraft noise and other potential sleep disturbance or
related health .effects responses have not been established by any of
these newer studies.
FICAN further cautions that these data should be applied only to
long term residents, although the inclusion of data from the opening
of Denver International Airport suggests that people adapt to "new"
noise rapidly. This curve should not be applied to estimate sleep
disturbance in campgrounds, trailer parks, or other temporary
residences. Nor should it be assumed that the curve can be
generalized to include children, as only adults were included in the
field studies.
The FICAN 1997 curve also is represented by the following equation:
Awakenings = 0.0087 x (SEL-30J~ 79
Continuing efforts to identify other dose-response relationships are
being undertaken by standards-setting organizations, such as the
American National Standards Institute. FICAN will evaluate proposed
relationships developed by such groups as they are published; until
that time, FICAN recommends the use of the curve presented here
for assessing potential sleep disturbance caused by aircraft noise.
Footnotes:
1. Actimeters are activity monitors, which record significant limb
movements over a long period of time. In sleep disturbance
studies, they generally are strapped to the wrist. Actimeters
are generally considered to be a more practical and cost-
effedive method of collecting physical sleep disturbance
data. Back
2. The use of single event measures in sleep disturbance
studies does not suggest that the nighttime penalties used to
assess noise in Day-Night Average Sound Level or other
cumulative measures are incorrect or need re-evaluation;
FICAN continues to support the use of DNL for addressing
cumulative impact and its underlying assumptions regarding
nighttime noise events. Back
Day-Night Average Sound Levels (DNL) at sites near Castle
AFB ranged from 50 to 90 dB, while DNL at sites near LAX
ranged from 60 to 70 d6. DNL at control sites ranged from
about 50 to 70 d6 (some control sites were exposed to high
levels of road traffic noise). Back
References
Federal Interagency Committee on Noise (FICON) (1992).
Federal Agency Review of Selected Airport Noise Analysis
Issues. Ft. Walton Beach, FL: Spectrum Sciences and
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Effects of Aviation Noise on Awakenings from Sleep
Software, Inc.
Fidell, S., K. Pearsons, R. Howe, B. Tabachnick, L. Silvati, and
D.S. Barber (1994).
Noise-induced Sleep Disturbance in Residential Settings
(AUOE-TR-1994-0131). Wright Patterson Air Force Base,
OH: Armstrong Laboratory, Occupational & Environmental
Health Division (AL/OEBN).
Fidell, S., K. Pearsons, R. Howe, B. Tabachnick, L. Silvati,-and
D.S. Barber (1995).
"Field study of noise-induced sleep disturbance." Journal of
the Acoustical Society of America, 98(2), 1025-1033.
Fidell, S., R. Howe, B. Tabachnick, K. Pearsons, and M.
Sneddon (1995).
Noise-induced Sleep Disturbance in Residences near Two
Civil Airports (Contract NAS1-20101) NASA Langley
Research Center.
Finegold, L.S., C.S. Harris, and H.E. VonGierke (1993).
"Applied Acoustical Report: Criteria for Assessment of Noise
Impacts on People." submitted to Journal of the Acoustical
Sociefy ofAmerica, June, 1992.
Finegold, L.S. (1993).
"Current status of sleep disturbance research and
development of a criterion for aircraft noise exposure."
Journal of fhe Acoustical Society ofAmerica, 94(3) Pt.2, 1807.
Griefahn, B., and A. Muzet(1978).
"Noise-Induced Sleep Disturbances and Their Effect on
Health." Journal of Sound and Vibration, 59(1): 99-106.
Lukas, J. (1975).
"Noise and Sleep: A Literature Review and a Proposed
Criterion for Assessing Effect." Joumal of the Acoustical
Society of America, 58(6 ).
Ollerhead, J.B., C.J. Jones, R.E. Cadoux, A. Woodley, B.J.
Atkinson, J.A. Horne, F. Pankhurst, L. Reyner, K.I. Hume, F.
Van, A. Watson, I.D. Diamond, P. Egger, D. Holmes, and J.
McKean (1992).
Report of a Field Study of Aircraft Noise and Sleep
Disturbance. London: Department of Safety, Environment and
Engineering.
Pearsons, K.S., D.S. Barber, and B.G. Tabachnick (1989).
Analyses of the predictability ofnoise-induced sleep
disturbance (HSD-TR-89-029). Brooks Air Force Base, TX:
Human Systems Division, U.S. Air Force Systems Command
(HSD/YA-NSBIT).
Pearsons, K.S., D.S. Barber, B.G. Tabachnick, and S. Fidell
(1995).
"Predicting noise-induced sleep disturbance." Journal of the
Acoustical Sociefy ofAmerica, 97(1), 331-338.
fFICAN Home ~ About FICAN ~ Activities ~ Research ~ Publications ~
News ~ More Info
Page 8 of 8
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Federal Interagency Committee on Aviation Noise
FICAN Position on Research into Effects of Aircraft Noise on Classroom Learning
September 2000
Research on the effects of aircraft noise on children's learning suggests that aircraft noise can interfere
with learning in the following areas: reading, motivation, language and speech acquisition, and memory.
The strongest findings to date are in the area of reading, where more than 20 studies have shown that
children in noise impact zones are negatively affected by aircraft. Recent research confirms conclusions
from studies in the 1970s showing a decrement of reading when outdoor noise levels are at an ~ of 65
d8 or higher. It is also possible that, for a given level of Lam, the effects of aircraft noise on classroom
learning may be greater than the effects of road and railroad traffic.
Members of FICAN are in agreement on the following: (1) Further work should be done to establish
whether school day L~ is the appropriate measure for determining the effect of aircraft noise on
classroom leaming. (2) In the absence of appropriations for specific research, FICAN encourages
"before" and "after" evaluations of the effectiveness of noise mitigation in schools. (3) FICAN will
undertake a pilot study to evaluate the effectiveness of school sound insulation programs. (4) FICAN
supports the work of the American National Standards Institute in its efforts to develop a standard for
classroom noise.
INTRODUCTION
The Federal Interagency Committee on Aviation
Noise (FICAN) has considered the issue of the effects
of aircraft noise on children's leaming, including:
reviewing relevant research; inviting U.S. researchers
[o a FICAN meeting; and conducting a symposium, to
which prominent international researchers were
invited to present their findings. The symposium was
held during the University of California's
Intemationa] Airport Noise Symposium, San Diego,
February. 2000. Speakers at the symposium
included: Dc Gary Evans of Cornell University,
Ithaca, NY; Dr. Staffan Hygge of the Royal Institute
of Technology, Gavle, Sweden; Dr. Stephen
Stansfeld, University of London, UK; Dr. Mary
Haines, University of London, UK; Mr. Lou
Sutherland, Consultant in Acoustics, California; and
Mr. David Lubman, Consultant in Acoustics,
California. Their presentations can be found on the
FICAN web site (www.fican.org).
This paper presents a summary of the research
presented at the symposium, and FICAN's
recommendations.
BACKGROUND
At the symposium, Dr. Gary Evans presented a
summary of research on the effects of noise on
children and learning. Research to date supports the
following findings:
Reading The strongest finding of a relationship
between aircraft noise and learning is in the area
of reading. More than 20 studies have found that
children in noise impact zones are negatively
affected by aircraft noise. Researchers are now
trying to identify a mechanism to explain the
cause-and-effect relationship nfthe observed
delay.
Moffvation Approximately a dozen laboratory
and field studies indicate reduced task
persistence in relation to uncontrollable noise.
Some of the research has identified a condition
of"learned helplessness": if one is continually
put in a situation where he or she has little
control over the environment, he or she may
"learn" helplessness.
Language and Speech A small number of
studies suggest delayed language acquisition and
interference with speech perception in noisy
areas. These data are potentially important
because they may provide a model for
understanding the linkage between noise and
reading. A fundamental building block of
reading is language - increasingly, research in
psycho-linguistics shows language acquisition is
critical to developing reading skills. When a
The Effects of Noise on Children's Learning
child is acquiring language in situations where
speech interference is common, it is quite
possible that delayed language may result,
leading to reading delay. This is especially true
of vulnerable children, such as those with hearing
problems and those who are teaming in a non-
native language.
Memory A few studies suggest deficits in shoR-
and long-term memory recall in the presence of
noise, particularly for more complex material
under noise. An interesting finding that has been
replicated with studies of adults is that the recall
is diminished more when the material is complex.
So if the task is easy, noise has little effect, but if
it is demanding, noise has a deteriorating affect.
RECENT RESEARCH
A number of recent studies support the general
findingg presented above. These include: studies of
the effects of noise on memory, the effects of noise on
cognitive performance as measured by standardized
test scores, and studies of the effects of aircraft noise
on vulnerable populations.
Effects on Memory: Dr. Staffan Hygge
Dr. Staffan Hygge has conducted a number of studies
that address the issue of the effect of noise on
memory and recall.
Classroom noise study In this experiment involving
children in their own classrooms, approximately
1,500 students were exposed to a variety of controlled
noise sources (tape recordings), including: aircraft
noise, rail noise, road traffic (highway) noise, and a
combination of the three. The students were exposed
to the same total noise level (L,,,,, 76 dBA, Leq 66
dBA for I S minutes, 24-hour Leq of42 dBA), and
events at approximately the same rate (8 events in 15
minutes). Testing was always conducted in [he
morning, at the peak of students' intellectual
alertness. Testing included three tests, under either
noise or silence conditions; test subjects' exposure
was reversed on the second test wave (i. e., students
tested in silence in the £rst wave were exposed to
noise in the second wave).
The results showed significant deterioration in recall
for the students exposed to both aircraft and highway
noise conditions, but there was no effect from rail.
page 2
When the test noise level was turned down to Leq 55
dBA, the effect of the road traffic dropped out, but
there was still an effect from aircraft noise. This
suggests that airport noise effects are worse than
highway noise effects, which are worse than rail
effects.
Munich Airport Study In this study, researchers took
advantage of the shut down of the old Munich Airport
and [he opening of the new Munich Airport. The
study followed 350 children at schools near both
airports. At the start of the study, children were 9
years old. Students were matched for highly exposed
and less exposed to aircraft noise. The students were
tested on a host of measures, including non-auditory
health effects beyond cognition and memory. The
test for long term memory was verysimilar to the one
conducted in the classroom noise study. Initially had
a disadvantage at old airport, which disappeared after
the old airport was shut down; on the other hand,
children near the new airport showed deteriorating
cognition levels over time.
Second classroom noise study In this study, high
school students were exposed to noise patterns that
included either "irrelevant" (nonsense) speech or road
traffic noise. The goal of the study was to evaluate
what kinds of memory systems and processes are
affected by noise.. Results showed that recall is
sensitive to noise -lower scores for both traffic noise
and silence, and the same reduction with irrelevant
speech. On attention, more errors were, observed in
both noise conditions than in silence.
Conclusions from all three studies taken together
suggest: (1) There appear to be effects of noise on
long term recall, particular with aircraft noise
exposure. It does not seem to matter if exposure is
acute (short-term) or chronic (long-term) noise
exposure. (2) The effects maybe reversible -
children originally exposed to aircraft noise in the
Munich exposed improved when the airport was shut
down.
The results of these studies put researchers in a
position to evaluate two possible patterns of
causation: in the £rst, one assumes that the primary
effect is on physiology -heart rate rises, then other
non-auditory responses follow. An alternative theory
supporting stress research suggests that the cognitive
system is affected 5rst, which must overcome
The Effects of Noise on Children's Learning
stressful situation, ultimately resulting in changed
perception and quality of life.
Effects on Health and Cognitive Performance:
Dr. Stephen Stansfeld and Dr. Mary Haines
Dr. Stansfeld and Dr. Haines presented the results of
three studies dealing with the effects of aircraft noise
on children's health and cognitive performance in the
vicinity of Heathrow Airport: the Schools
Environment and Health Study, the SATs Study, and
the West London Schools Study.
Schools Environmenf and Health Study This study
was commissioned as part of an Inquiry investigating
the constmction of fifth terrttinal at Heathrow. The
aim of the study was to examine the effects of chronic
noise exposure on children's health and cognition.
The researchers evaluated baseline (1996) reading
comprehension and noise annoyance, cortisol
secretion (to identify possible stress) and mental
health indicators (anxiety and depression). At follow-
up (1997), the researchers tested reading, sustained
attention, annoyance, and perceived stress.
One of the objectives of [he study was to test the
hypothesis that interference with sustained attention is
a possible causal factor in reduced cognitive
performance; that is, if attention levels aze decreased,
lower reading skills may result. Researchers also
wanted to evaluate vulnerable populations by
controlling for socio-economic status (SES).
Researchers evaluated primary age children aged 8-
1 l in four sthools near the airport, matched to four
schools with lower noise levels. Tests were
administered in [he classroom; simultaneous noise
measurements at the schools were conducted, and
home noise levels were determined from Civil
Aviation Authority (CAA) contours. Schools were
matched for SES, other background noise, and
ethnicity. -
The results of the analysis showed that the high-noise
area schools contained significantly more non-white,
non-English speaking, socially deprived children.
Reading comprehension scores showed that in the
high noise group, children were statistically
significantly delayed-approximately asix-month
difference in reading age. Children in the high-noise
schools were also more highly annoyed by aircraft
noise; however, children's annoyance response did
not match parents' response. Measurements of
page 3
cortisol levels did not show significant differences
either at the beginning or end of testing; this may
suggest cortisol is not appropriate hormone to
evaluate for stress levels in children. Other
behavioral testing shows that aircraft noise does not
appear to increase depression or anxiety.
At follow-up (one year later), children exposed to
high levels of noise had poorer reading, and sustained
attention; however, no there was no significant
finding that attention was underlying reason. The
stress responses replicated the effect of annoyance:
children exposed tc high noise had greater
annoyance. Researchers wanted to clarify this more:
could it be that children in high-noise areas had mare
stress responses? Researchers tested children on
how would they feel if stressful life events happened
to them. The children in the high noise schools
reported higher responses (would feel more stressed
in a stressful situation), although they did not have
significantly more actual stress events in their lives.
This may be an indicator of coping style -perhaps
supporting the "learned helplessness' theory.
How did children adapt over the year? Test scores
were analyzed by adjusting for baseline performance.
It appears that the effects increased over time -
progress by students in high noise schools was lower
than progress for children in low noise group.
However, when adjusted for socioeconomic status
and main language spoken at home, the effect was
eliminated-this may be a result of sample size. In
terms of annoyance, [he effect stayed the same. In
summary, annoyance effects appeared to stay the
same, whereas reading effects seemed to worsen over
the year.
Scholastic Aptitude Sfudy (SA TS) This was a multi-
level modeling study looking at effects of aircraft
noise on the test results in reading, mathematics, and
science. The study examined 128 primary schools
around Heathrow Airport, trying to answer the
following questions:'(1) whether previous
associations between noise level and cognitive
performance were confounded by either social class
or school quality, and (2) does noise affect language-
based tasks more than math or science tasks. For
eleven-year olds, researchers evaluated 11,000 scores
from 128 schools exposed to a range of aircraft noise
exposure, based on CAA contours for 16-hour Lqs, in
3 dB bands - to try to get a dose response curve
(noise levels ranged from 54 dBA to 72 dBA).
The Effects of Noise on Children's Learning
The statistical model used to evaluate the data
adjusted for sex, year (age), type of school (public,
private), and social deprivation (% eligible for free
school meal). Researchers did not find a main effect
on English, but did find a main effect on
Mathematics; this was a surprising finding. As noise
bands increased, scores on math tests dropped;
however, when adjusted for social deprivation, the
statistical significance is lost. There appeared to be
no effect on science. When scores in English were
examined further, researchers found that there was an
effect on reading, though not on spelling,
handwriting, and writing. As for mathematics, there
was adose-response effect for reading. Results of the
SATS study suggest that chronic exposure to aircraft
noise is associated with school performance in
reading and mathematics; because the mathematics
results were so strong, the smdy suggests that the
effects of noise may not be limited to language-based
tasks. Adose-response function was identified for
both effects; however, after adjusting for social
deprivation, the effect is lost.
The social deprivation question is very complex: it
may be that social deprivation is [he primary force in
determining pedormaape, that noise is a mediator
serving to worsen the effect - in this case it would be
wrong to adjust for social deprivation. On the other
hand, it may be that social deprivation had a
moderating affect on the relationship between aircraft
noise and performance -noise causes deficit in
cognition, but that is made worse in a situation of
social deprivation. Researchers believe that there is a
need to investigate whether there is a relationship
between social deprivation and selection into noisy
areas.
Wesf London Schools Sfudy This smdy isjoindy
funded 6y UK Department of Health and Department
of Transport and Environment a larger smdy similar
to the Schools Environment and Health Smdy. The
aims of the study aze to confirm that chronic levels of
high aircraft noise exposure in children are associated
with cognitive impairment, reading, memory, and
attention. Stress responses are now being evaluated
in terms of catecholamine secretion (a finding of the
Munich Smdy), noise annoyance, and self-reported
stress levels. The mode] will adjust for individual
and school-level confounding factors. Researchers
also want to look at issue of social deprivation.
page 4
around Heathrow. Researchers will carry out
analyses at school and individual level, and will
conduct noise measurements at the time of testing at
the schools. The study also will collect data on
personal dosimetry on asub-sample of the children,
as well as as additional sub-sample to evaluate
qualitative effects: How do they feel about noise?
Preliminary results of the West London Schools
Study suggest that children from high noise schools
heard more aircraft noise and were more annoyed by
aircraft noise than children from low noise schools,
but did not differ substantially on road noise.traffic
annoyance. Further analyses will examine aircraft
noise exposure in relation to cognitive outcomes,
adjusting for confounding, and taking into account
both individual and school level factors.
ANSI Standard: David Lubman and Lou
Sutherland
Mr. Sutherland and Dr. Lubman are co-chairs of
Working Group 42 of the ANSI 5-12 Noise
Committee, which is working to develop a standard
for classroom acoustics. The Working Group is
working directly with the U.S. Access Board, who
implements the Americans with Disabilities Act. This
is significant because adoption by the Access Board
carries the weight of law.
The proposed standard will be applied primarily to
new school construction, not for existing schools.
The standard is still being developed, but will
probably include the following elements:
A limit for interior ambient noise in classrooms:
the Swedish guidelines call for 30 dBA interior
noise level, as does the American Speech,
Language and Hearing Association.
A limit for reverberation time in classrooms: e.g.,
0.4-6 sec in rooms where speech is important
(i.e., classrooms, auditoria).
Minimum sound insulation between spaces.
To deal with aircraft noise levels, the standard
may take into account aircraft flyovers by
identifying an acceptable Time Above threshold
level -however, the threshold and amount of
time have yet to be determined. The standard
may also address an acceptable number of events
in a certain time period.
The smdy includes ten high•noise schools matched
with 10 control schools; again, drawn from areas
The Effects of Noise on Children's Learning
A noise measurement protocol, methods for
performance validation, and design guides and
checklists.
One of the major goals of the standazd is to simplify it
so that it is easy to implement and easy to measure at
the individual school level.
ADDITIONAL RESEARCH
Presenters at the symposium believe that there aze a
number of areas where more reseazch is needed.
These include:
Dose-response functions, Thresholds, Mefrlcs
Researchers are now fairly confident that a
relationship between noise and its effects on
some aspects of leaming exist. One of the major
unresolved problems, though, is identifying a
level at which aircraft noise is problematic, as
well as identifying levels of change which result
in changes in learning. Most of the studies have
identified students as exposed to a "noisy" or
"quiet" environment, with little regard given to
developing a curve which shows responses at
varying noise levels. There is one dose-response
function for relating reading and noise, but it is
difficult to translate to DNL.
Underlying Mechanisms and Processes An
understanding of how the effect works is
important for identifying policy, because if we
understand what is causing the problem we may
be able to develop more sophisticated and
tazgeted policies and interventions.
More 7harough Psycho-acoustic Intarmaflan
Another related issue is the choice of noise
metric: most studies have identified "noisy"
environments based on DNL orLeq - it may be
that these aze notappropriate metrics for two
reasons: first, both DNL and Leq were developed
to address issues of annoyance, not cognitive
development or health; and second, DNL
imposes a nighttime penalty which is largely
irrelevant for describing classroom noise levels,
and may if fact, provide a misleading measure.
Perhaps we should be looking at things such as
speech interference levels (SIL) and
reverberation times. More research needs to be
conducted to identify which noise metrics are
appropriate far measuring learning responses.
page 5
Vufnarahilify Many environmental regulations
are built with a mazgin of safety; (e.g., air
pollution levels include margin of safety to
protect asthmatics); we have not given much
thought [o an analog for noise. More research
needs to be done on the effects of noise on
specific, vulnerable populations,including -
childrenwith lower aptitudes, children with
hearing problems, and children who are leaming
in anon-native language. Should classroom
noise standards build in a "margin of safety" to
protect these vulnerable populations?
Ecological Perspective To date, most of the
research has focused strictly on the children.
Research should be expanded [o address the
entire learning environment, including the effects
of noise on teachers' motivation and parents'
motivation. A small amount of research suggests
that there may be some changes in teacher and
parent behavior in the presence of noise. Many
of these studies also have a potential for
confounding, for example poverty. Mast of the
research controls for these kinds of variables.
However, what if poverty interacts with noise -
what if noise, in the context of other situations,
interacts with other affects to amplify them? In
studies where we have controlled for socio-
economic data, we may have understated some of
the effects of noise.
RECOMMENDATIONS
FICAN makes the following recommendations:
Metrics Further work should be done to
establish whether school day irts is the
appropriate measure for determining the effect of
aircraft noise on classroom leaming. An
important question is the role of classroom
interruptions. For example, would a teacher
pausing for the flyover of an aircraft at x dB
every 20 minutes have the same effect on
classroom learning as pausing for an aircraft at
x-10 dB every 2 minutes? Although the two
cases would result in equal outdoor I.,s, the
interruption pattern would be different, and the
effects on classroom learning could be different.
At what indoor sound level does a teacher pause?
Is SEL the best predictor of interruption? In
posing these questions, the members recognize
that such studies are difficult and expensive to
The Effects of Noise on Children's Learning
perform, and none of the FICAN participants
have funding for such research. Nor is it clear
which agencies, if any, have a mandate to
conduct such research.
Effectiveness ofsoundinsu/atlon In the
absence of appropriations for specific research,
FICAN encourages "before" and "afer"
evaluations of the effectiveness of noise
mitigation in schools. In the past, the inforrttation
on effectiveness of noise reduction in classrooms
has been anecdotal rather than systematic.
Through its website, FICAN is in a position to
serve as a repository for "before" and "after"
evaluations. FICAN invites noise-impacted
communities, school boards, administrators,
principles, teachers, and parents to address
questions and information about "before" and
"after" studies to our website.
Ia conducting these evaluations, the following
evaluators are recommended: (1) "Before" and
"after" noise measurements in treated classrooms
taken during school hours on days when
classrooms are unoccupied. Guidelines for
low-cost assessment of classroom noise will soon
be available in the form of an American National
Standazds Institute publication. (2) "Before"
and "after" academic scores, particularly for
reading and math, from children using the treated
classrooms. (3) "Before" and "after" teacher
evaluations from teachers working in the treated
classrooms.
FICAN will undertake a pilot study to evaluate
the effectiveness of school sound insulation
programs in the following areas: (1) improved
academic performance, as measured by
standazdized test scores; and (2) improved
learning environments, as reported by classroom
teachers. The study will also identify methods
for conducting further research, if needed, and
.define the scope of the issue on a national basis.
Standards for classroom nolse FICAN
supports the development of an ANSI standard
for classroom acoustics. FICAN encourages the
working group to keep FICAN informed of
progress on [his matter.
page 6
REFERENCES
Bronzaft, A., and McCarthy, D. (1975). The effects
of elevated train noise on reading ability.
Environment and Behavior, 7 pp. 517-527.
Green, K., Pastemack, B, and Shore, R (1982).
Effects of aircraft noise on reading ability ofschool-
age children. Archives of Environmental Health, 37,
PP 24-31, 1982. -
Bollinger, M., Hygge, S., Evans, G.W., Meis, M., &
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page 7
ADDITIONAL INFORMATION
Additional information can also be found at the
following web sites:'
Web PagelOrganlzatlon Web Page Address
FIGdJ hltpalwww.fican. org
Instflule for Environment hdp:lNrww.le.ac.u~eh
antl Health
Classroom Acoustics htlp:/Awm.classroomacoustics.com
Home Page
GAO Rapons on School htlp9lwwv+.edfacililies,com
Facilities
Boats Petition antl hltp:/Nrww.access-board.govlmles7
Request for lnlormalion acousdahtm
Acoustlctlesign ai ht(p:1lwww.designshare.coMReseamh
childcare facilities lLMaxwelVNOiseChildren,hlm
Alan F. Zusman, FICAN Chairman
Department of the Navy
Chief of Nava] Operations, N44E
Washington Navy Yard
1322 Patterson Ave, SE
Washington, DC 20374-5065
voice: 202.685.9181
fax: 202.685.1577
email: zusmanaf@navfac.nary.mil
Health-report
Tuesday, Apri125, 2000
Page 1 of 2
Urban noise a growing problem, new report
claims
Detrimental effects: In advance of police 'copter trials, health
officials worry about sound's impact
Robert Bennie
National Post
Toronto Police Video
A helicopter flies over downtown Toronto
in an image from a Toronto Police video
created to demonstrate the effectiveness of
air patrols over the city's 630 square
kilometres. A pilot project will begin in July
and end Dec. 31:
As Toronto police prepaze for the potentially noisy launch of a helicopter pilot project this summer, the city's public health .
department is trying to raise awareness about the growing problem of urban noise.
In a report to be tabled at the Boazd of Health meeting on Monday, Dr. Sheela Basrur, Toronto's medical officer of health,
urges the city's various branches of government to work together to address the issue.
"It is recommended that the medical officer of health, the commissioner of urban development services and the commissioner
of works and emergency services collaborate on their respective public outreach activities regarding the health effects of
noise and measures to prevent or minimize noise in the community," writes Dr. Basrur.
Noting [hat the population of the Greater Toronto Area is expected to increase by 40% over the next 20 yeazs and that the
expansion of Pearson Airport will see a rise of air traffic from 27-million passengers annually to 50-million by 2010, she said
indications are that the city is getting noisier.
"[Downtown Toronto] is becoming known as a centre for music festivals on city streets, parks and public areas. This increase
in public leisure activities will likely add to the noise levels in the city."
While the report does not specifically refer to helicopters, it points out that a cause for concern is "low frequency noise
from ... vehicles, aircraft, industrial machinery and air movement machinery, including wind turbines, compressors, indoor
ventilation and air conditioning units."
Prolonged exposure to these types of sounds can have detrimental effects on health. According to Dc Basmr, "excessive
noise can also induce or aggravate stress-related health outcomes, including those on the cardiovascular system, immune
system, sleep, task performance, behaviour and mental health."
Her study will be presented exactly two months before a patrol chopper gets airborne on Suly 1.
As disclosed by the National Post last month, Needless Noise, a 68-page report by the National Resources Defense Council
(NRDC), a U.S. think-tank, concludes that helicopters hovering over residential azeas pose a health hazard.
"Aircraft noise has been found to produce a number of adverse health effects, ranging from headaches, sleep dismption and
hypertension to compromised cardiovascular and gastrointestinal functions," says the American study, completed last
http://www3.sympatico.ca/noise/health-rpt.htm 5/29/2003
Wieland Associates Experience With Heliport Noise Studies, Acoustical Consultants; Noi... Page 1 of 1
Heliport Noise Assessment Studies
The Proh&'m: Because of the unique character of helicopter noise, which includes a phenomenon called
"blade slap", heliports can face close scnitiny by public agencies and local citizens when they are proposed
for development. Existing heliports are also a source of frequent complaints by residents near the flight
parh.
The Solution: Conc{uct a study to accttrately assess the noise levels and exposures that will. be generated by
the haGport, and to assess the umocance potential aF the. helicopter Elu;hts. This assessment should be based
on noise measurements of actual helicopter operations. Finally, the noise studv shotild identify mitigation
measures that will achieve compliance with cotrttnunitynoise standards and will nununize annoyance within
the conununity.
Experience: The following provides a brief listutg of Mi•. lvieland's experience w7th preparing noise
assessment studies for heliports:
, Police Department heliport, Ontario, C.A
Airspur cornn~rcial helicopter sere-ice at Fullerton Municipal Airpon, Ftillerton, CA
Helicopter operations at Torrance Municipal Airport, Torrance, CA
Anaheun police department helicopter operations, Anaheim, CA
Santa .'\tta-Tustin Coauntuuty Hospital helipad, Santa Ana, CA
Helipad at the Chteen of the Valley hospital, Covina, CA
Secttrity Pacific National B~u~lc heliport, Brea, CA
Pil Hughes .Aircraft Company helipad, Anaheim, GA
http://www.wielandassoc.com/Heliports.html 5/29/2003