Noise and its Abatement

32 Pages·2011·4.55 MB·English

Division 44
Water, Energy, Transport
Noise and its Abatement
Module 5c
Sustainable Transport: A Sourcebook for Policy-makers in Developing Cities
Overview Of the sOurcebOOk
sustainable transport:
A sourcebook for Policy-Makers in Developing cities
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A practical orientation, focusing on best
practices in planning and regulation and,
where possible, successful experiences in
developing cities.
Contributors are leading experts in their
fields.
An attractive and easy-to-read, colour layout.
Non-technical language (to the extent
possible), with technical terms explained.
Updates via the Internet.
Modules and contributors
(i) Sourcebook Overview and Cross-cutting Issues vehicles and fuels
of Urban Transport (GTZ)
4a. Cleaner Fuels and Vehicle Technologies
institutional and policy orientation (Michael Walsh; Reinhard Kolke,
Umweltbundesamt – UBA)
1a. The Role of Transport in Urban Development
4b. Inspection & Maintenance and
Policy (Enrique Peñalosa)
Roadworthiness (Reinhard Kolke, UBA)
1b. Urban Transport Institutions
4c. Two- and Three-Wheelers (Jitendra Shah,
(Richard Meakin)
World Bank; N.V. Iyer, Bajaj Auto)
1c. Private Sector Participation in Urban
4d. Natural Gas Vehicles (MVV InnoTec)
Transport Infrastructure Provision
(Christopher Zegras, MIT) 4e. Intelligent Transport Systems
(Phil Sayeg, TRA; Phil Charles,
1d. Economic Instruments
University of Queensland)
(Manfred Breithaupt, GTZ)
4f. EcoDriving (VTL; Manfred Breithaupt,
1e. Raising Public Awareness about Sustainable
Oliver Eberz, GTZ)
Urban Transport (Karl Fjellstrom, Carlos F.
Pardo, GTZ) environmental and health impacts
1f. Financing Sustainable Urban Transport
5a. Air Quality Management (Dietrich Schwela,
(Ko Sakamoto, TRL)
World Health Organization)
1g. Urban Freight in Developing Cities
5b. Urban Road Safety (Jacqueline Lacroix,
(Bernhard O. Herzog)
DVR; David Silcock, GRSP)
Land use planning and demand 5c. Noise and its Abatement
management (Michael Jaecker-Cueppers,
Civic Exchange Hong Kong; GTZ; UBA)
2a. Land Use Planning and Urban Transport
5d. The CDM in the Transport Sector
(Rudolf Petersen, Wuppertal Institute)
(Jürg M. Grütter)
2b. Mobility Management (Todd Litman, VTPI)
5e. Transport and Climate Change (Holger Dalk-
2c. Parking Management: A Contribution
mann; Charlotte Brannigan, C4S)
Towards Liveable Cities (Tom Rye)
5f. Adapting Urban Transport to Climate Change
transit, walking and cycling (Urda Eichhorst, Wuppertal Institute)
3a. Mass Transit Options 5g. Urban Transport and Health
(Lloyd Wright, ITDP; Karl Fjellstrom, GTZ) (Carlos Dora, Jamie Hosking,
3b. Bus Rapid Transit Pierpaolo Mudu, Elaine Ruth Fletcher)
(Lloyd Wright, ITDP)
resources
3c. Bus Regulation & Planning
6. Resources for Policy-makers (GTZ)
(Richard Meakin)
3d. Preserving and Expanding the Role of Non- social and cross-cutting issues on
motorised Transport (Walter Hook, ITDP) urban transport
3e. Car-Free Development 7a. Gender and Urban Transport: Smart and
(Lloyd Wright, ITDP) Affordable
(Mika Kunieda; Aimée Gauthier)
i
About the author
Michael Jaecker-Cueppers is a consultant on
traffic noise abatement for the Federal German
Ministry of Environment, Nature Conservation
and Nuclear Safety (BMU) and for the Euro-
pean NGO Transport&Environment. He is a
lecturer on Urban Noise Control at the Techni-
cal University of Berlin. He worked for 27 years
for the German Federal Environmental Agency
(UBA) in the Unit “Traffic Noise Abatement”.
He is also chairman of the German NGO
“Arbeitsring Lärm der DEGA” ALD, which
fights for better noise abatement in Germany
and Europe.
ii
Module 5c
urban transport and health
Disclaimer
Findings, interpretations and conclusions
expressed in this document are based on infor-
mation gathered by GIZ and its consultants,
partners and contributors from reliable sources.
GIZ does not, however, guarantee the accuracy
or completeness of information in this docu-
ment, and cannot be held responsible for any
errors, omissions or losses which emerge from
its use.
Author: Michael Jaecker-Cueppers (2011 revision)
Based on earlier versions of this document
prepared by GIZ with contributions from
Tam Pui-ying, FHWA and Frank Kraatz
Editor: Deutsche Gesellschaft für
Internationale Zusammenarbeit (GIZ) GmbH
P. O. Box 5180
65726 Eschborn, Germany
http://www.giz.de
Division 44 – Water, Energy, Transport
Sector Project "Transport Policy Advisory Services"
On behalf of
Federal Ministry for Economic Cooperation
and Development (BMZ)
Division 313 – Water, Energy, Urban Development
P. O. Box 12 03 22
copyright 53045 Bonn, Germany
This publication may be reproduced in whole or Friedrich-Ebert-Allee 40
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edgement of the source is made. The GIZ would Editing: Dominik Schmid
appreciate receiving a copy of any publication
Cover photo: Roger Krichbaum, Mumbai, India, 2002
that uses this GIZ publication as a source. No
Layout: Klaus Neumann, SDS, G.C.
use of this publication may be made for resale
or for any other commercial purpose whatsoever. Eschborn, November 2011
iii
TABLE OF CONTENTS
1. introduction 1
2. Aspects of noise 2
2.1 Describing sound 2
2.2 Characterising noise levels 4
3. sources of road noise 5
4. the nature and scale of impacts 6
4.1 Health effects of noise 6
4.1.1 Introduction 6
4.1.2 Effects of noise on human hearing 6
4.2 Societal Economic Costs of Noise Pollution 7
4.2.1 Introduction 7
4.2.2 Effect of noise on human activity 7
4.3 Factors contributing to noise impacts 9
4.3.1 Vehicular factors 9
4.3.2 Road surfaces 9
4.3.3 Road geometry 9
4.3.4 Environmental factors 9
4.3.5 Spatial relationships 10
4.3.6 Traffic stream 10
5. remedial measures 12
5.1 Raising public noise awareness 12
5.2 Avoiding motorised traffic 13
5.3 Noise reception level standards 13
5.4 Motor vehicle control 14
5.5 Land use control 15
5.6 Traffic management 15
5.7 Surface design and maintenance 15
5.8 Road geometry and design 16
6. Lessons learned from Noise Action Planning in europe 19
7. conclusion 23
8. references and resources 24
iv
Module 5c: Noise and its Abatement
1. introduction
box 1: Noise in developing cities:
is it a problem?
Noise has always been an important environ-
mental problem. In ancient Rome, rules existed There is a widespread view that noise from
transport is currently not a critical issue for
as to the noise emitted from the ironed wheels
de veloping cities, especially compared to other
of wagons which battered the stones on the
en vironmental issues such as air pollution. This
pavement, causing disruption of sleep and
view is exemplified in the World Bank Urban
annoyance to the citizenry. In Medieval Europe,
Transport Strategy Review (http://www.world-
horse carriages and horse-back riding were not
bank.org/transport, 2001), which states that:
allowed during night time in certain cities to
Noise from transport appears to be con-
ensure peaceful sleep for inhabitants. However,
sidered much less seriously in developing
the noise problems of the past are incompara-
countries than in high income countries.
ble with those of modern society. An immense While there have been studies of the
number of cars, motorcycles, trucks and other physical damage resulting from exposure
motorised vehicles criss-crosses developing to occupational noise these have been
cities, day and night. In comparison to other mostly in manufacturing establishments.
pollutants, the control of environmental noise The levels experienced in the streets of
developing countries, while not pleasant,
has been hampered by insufficient knowledge
approach but do not exceed the lower
of its effects on humans and of dose-response
limits above which noise is considered
relationships as well as a lack of defined criteria.
an occupational hazard.
While it has been suggested that noise pollution
Evidence from dense Asian cities such as Hong
is primarily a "luxury" problem for developed
Kong or Bangkok, however, suggests that noise,
countries, exposure to noise is often higher
even if currently not a high priority issue in
in developing countries, due to higher densi-
developing cities, will in coming years increas-
ties, and poor planning and construction. The
ingly represent an important public health issue
effects of the noise are just as widespread and in rapidly motorising, dense developing cities.
the long term consequences for health are the
same. In this perspective, practical action to
limit and control the exposure to environmental sources most commonly affected private study,
noise are essential (WHO, 2002). although personal emotional states and classes
were also disrupted, through loss of concentra-
Noise pollution in large developing cities is
tion, annoyance and frustration, and anxiety
an insidious issue. In such noisy cities, many
and stress.
people seem to have become accustomed to the
higher noise levels that underpin their daily Though it receives a large number of complaints
activities. Yet in a city such as Hong Kong, for from citizens, few consider noise to be a seri-
example, noise is the most common cause of ous health hazard. However, noise has not only
complaints. Of the 23 678 environmental com- been linked to many serious health risks, such
plaints received by the Hong Kong Environ- as hypertension and heart disease, but also to a
mental Protection Department (EPD) in 2010, deteriorating quality of life, by interfering with
29 % were noise related (http://www.epd.gov.hk/ speech, performance, and ultimately, productiv-
epd/english/laws_regulations/enforcement/pollu- ity. In many large developing cities, those who
tion_complaints_statistics.html). The Hong Kong have not been physiologically damaged by noise
Institute of Acoustics carried out a noise survey may nevertheless have been mentally affected
to assess the degree of noise pollution suffered by it. Recently citizens in developing countries
by the public (see http://www.hkioa.org). From start to organize initiatives against noise. One
the roughly 100 responses, the most serious example is “Quiet Bangkok” which fights
source of noise pollution was seen to be con- against noise pollution in Bangkok (see http://
struction noise, followed by traffic noise. These www.quietbangkok.org/index.en.html)
1
Sustainable Transport: A Sourcebook for Policy-makers in Developing Cities
distributed on a logarithmic scale. Thus sharply
2. Aspects of noise
painful sounds, which are 10 million times
greater in sound pressure than the least audible
Noise is unwanted and impairing sound. Sound
sound, are in decibels simplified logarithmically
has a range of different physical characteristics,
to a manageable range for comparison.
but only becomes noise when it has an undesir-
able and detrimental physiological or psycho- Frequency, perceived as pitch, is determined by
logical effect on people (see Section 4). Environ- the rate at which sound makes the air vibrate.
mental noise refers to noise that can affect our Time pattern refers to a sound’s pattern of time
surroundings, and includes construction noise, and level, which can be continuous, intermit-
machinery noise, transportation noise, as well as tent, fluctuating, or impulsive. Continuous
domestic noise. sound is a constant level of sound for a relatively
long period, such as the sound of a waterfall,
Sound is created when vibrations in the air move
whereas intermittent sound is sound produced
particles in a wave-like pattern that are perceived
for short periods, such as the ringing of a tel-
by the ear. The pressure waves are then con-
ephone. Fluctuating sound varies in level over
verted into ionic and electric events by sensory
time, such as the loudness of traffic sounds in a
cells in the cochlea, creating nerve impulses that
busy intersection, and impulsive sound is sound
are interpreted by the brain as sound.
produced in an extremely short span of time,
such as a pistol shot (US EPA, 1979).
2.1 Describing sound
Sound may be described in terms of amplitude, Noise measurement units
frequency, and time pattern. Amplitude, per- It is common international practice to determine
ceived as loudness, is the fundamental measure noise in terms of levels which are expressed as a
of sound pressure used in most measurements of logarithmic function L of the sound pressure and
environmental noise. The sound pressure levels adapted to the sensitivity of the human ear.
are measured in decibels (dB), and the range is
Environmental sound is typically measured by
four descriptors which are used to determine the
impact of environmental noise on public health
table 1: typical sound levels
and welfare. These are: the A-weighted Sound
encountered in daily life and industry
Level L , A-weighted Sound Exposure Level
Ap
Activity Sound level (dB(A)) SEL, Equivalent Sound Level L , and weighted
eq
Desert 10 Sound Levels for the whole day (day-night L ,
dn
Rustling leaves 20 day-evening-night Lden). The A-weighted sound
level (dB(A)) is the most common measure
Room in a quiet dwelling at midnight 32
of expressing noise (compare box ‘sound level
Soft whispers at 5 feet 34
measurements’).
Men’s clothing department of large store 53
A conversation in a quiet living room would
Window air conditioner 55
register at 60 dB(A), average road traffic 25 m
Conversational speech 60
away from a busy primary road would register
Household department of large store 62
at 70 dB(A), and a diesel freight train at 25 m
Busy restaurant 65
would register at around 80 dB.
Vacuum cleaner in private residence (at 10 feet) 69
Box 4 gives the noise levels recommended for
Ringing alarm clock (at 2 feet) 80
specific environments (dwellings, schools and
Loudly reproduced orchestral music in large room 82
pre-schools, and hospitals), though it should be
Prolonged exposure – beginning of hearing damage 85
noted that few places in many large developing
Lorry or motorbike close by 90
cities achieve the recommended level.
Rock concert, loud disco 100
To get an impression of dB(A) values, Table 1
Pneumatic drill 110
provides a list of sound levels from typical situ-
Jet aircraft take-off 130
ations, and Figure 1 provides a graphic scale of
Gunshots, explosions 140
transport-oriented sound levels.
Tam 2000
2
Module 5c: Noise and its Abatement
Due to the logarithmic scale, a 3 dB(A) increase fig. 1
in sound levels represents a doubling in noise. Scale of sound levels.
However, since the measurement of noise and World Bank, 1997
the perception of noise do not always coincide, a
doubling of sound intensity projected by the sci-
entific scale with a 3 dB(A) increase may only be
perceived by humans after a 10 dB(A) increase
(Tam, 2000). The loudness of sounds (namely,
how loud they seem to humans) varies from
person to person, so no precise definition of
loudness is possible. However, the FHWA (1992)
notes that based on many tests, a sound level of
70 is twice as loud to the listener as a level of 60.
This principle is illustrated in Figure 2.
fig. 2
ThreNBsorhoromalddaRc leo aBffsr rHiteg LSeaeibtatruharrdaiitnnoriggoyr dBAdBAdBA0dBA1020dBA304050 dBA 2 times louder than 50 dBA 4 times louder than 50 dBA 8 times louder than 50 dBA Perceived as 16 times loud ThdFHoWueA b,p 1lr9i9in2ngc inpolies eo.f
e
Clothes Dryer dBA50 r tha
Air-Conditioning Unit dBA60 n 50 d
At 50 m Pickup Truck dBA70 BA
ph and 50 feetModifieMde Mdioutmo rTcryucclek dBA80 dBA90
Figure 3 shows the noise transmitted or propa- emission transmission reception
gated from a mobile emitting source to a receptor.
The emissions of a source and consequently the
reception levels are usually not constant. For
moving sources such as road traffic noise, the
source
noise level is constantly changing with the
Defracted sound
number, type, and speed of the vehicles which
produce the noise.
The equivalent acoustic level (L ) is the sound barrier receptor
eq
level of a stable noise which contains the same
energy as a variable noise over the same period.
It represents the mean of the acoustic energy Nocturnal noise levels are generally lower than fig. 3
perceived during the period of observation. during the day. For example, the nocturnal L Emission, transmission
eq
The equivalent acoustic level of noise during (12:00–6:00) is typically 10 dB below the L and reception of noise.
eq
the period 8:00–20:00 is written as L (8:00– (8:00–20:00), except in the case of especially
eq
20:00) or L (12 h). high nocturnal traffic with a high percentage of
eq
heavy goods vehicles or freight wagons.
L (12 h) is an alternate measure, indicating
10
the noise level exceeded 10 % of the time over The equivalent acoustic level L in front of
eq
a twelve-hour period. For the 18-hour period (outside) a building facade facing the traffic
6:00 to 24:00, L (18 h) is typically 3 dB(A) determines the building’s exposure to noise.
10
higher than L for the same period. This is the most commonly used indicator of the
eq
3
Sustainable Transport: A Sourcebook for Policy-makers in Developing Cities
discomfort caused to the building occupants information). In the European Union the
(World Bank, 1997). For sleeping disturbances development of common assessments meth-
the maximum indoor level L is another ods (“CNOSSOS”) which shall replace the
A,max
important indicator. L is also relevant various national prediction schemes is planned
A,max
for single event levels that may cause hearing for 2012 (see http://circa.europa.eu/Public/
impairments. irc/env/noisedir/library?l=/material_mapping/
cnossos-eu&vm=detailed&sb=Title).
Forecasting noise levels
It is common practice to calculate noise recep-
2.2 characterising noise levels
tion levels, for various reasons:
Traffic noise variations can be plotted on a
„„A prognosis of future noise situations is only
graph as shown in Figure 4. However, it is usu-
possible on the basis of calculations;
ally inconvenient and cumbersome to represent
„„Measurements are influenced by random fac-
traffic noise in this manner. A more practical
tors such as meteorological conditions and
method is to convert the noise data to a single
source characteristics, making it costly to get
representative number. Statistical descriptors
representative results.
are almost always used as a single number to
Forecasting methods include equations, com-
describe varying traffic noise levels. As men-
puter modelling and physical models, though
tioned above, the three most common descrip-
equations which estimate noise based on traffic
tors used for traffic noise are L , L and L .
flow, composition and speed are simplest. The 10 eq A,max
L is the sound level that is exceeded 10 % of
applied calculation schemes are based on emis- 10
the time.
sion and propagation assumptions which are
normally gained by measurements. In Figure 4 the shaded areas represent the
amount of time that the L value is exceeded.
Examples of computer noise models in use 10
Adding each interval during which this
are the FHWA Highway Traffic Noise Predic-
occurred shows that during the 60-minute
tion Model (FHWA-RD-77-108), and the
measuring period the L was exceeded 6 min-
Traffic Noise Model 2.5 (TNM), which is 10
utes (½ + 2 + 2 + 1½ = 6) or 10 % of the time.
operational since 2004 (see http://www.fhwa.
The calculation of L is more complex. L is
dot.gov/environment/fhwa_tnm.htm for more eq eq
the constant, average sound level, which over
a period of time contains the same amount of
box 2: sound level measurements sound energy as the varying levels of the traffic
noise. L for typical traffic conditions is usu-
The A-weighted sound level measures sHouignhdw oany aT sracfafliec tNhaoti se - FHWA eq Page 3of 7
ally about 3 dBA less than the L for the same
closely mirrors the way it is heard by people, by giving more 10
conditions. L is the A-weighted maximum
weight to the frequencies that people hear more easily, within A,max
sound level, i.e. the maximum pass-by level of a
1–6 kHz.
vehicle, which is among others relevant for sleep
A-weighted Sound Exposure Level (L) mea su res the total energy
s disturbances.
of sound by summing the intensity during the exposure dura-
tion, accounting for the variation in sound levels from moving
sour ces such as airplanes, trains, or trucks, in order to measure
environmental noise. A-weighted Equivalent Sound Level (L )
Aeq
is used to measure average environmental noise levels to which
people are exposed. It expresses a single value of sound level
for any projected duration, including all of the time-varying
sound energy in the measurement period, and is used when
the duration and levels of sound, and not their occurrence (day/
night), are relevant. When the occurrence of sound is relevant,
such as in residential areas, the Day-Night Sound Level (L ) is
dn
used. This A-weighted equivalent sound level covers a 24-hour
In the above graph, the shadfeidg .a 4reas represent the amount of time that the Llo value is exceeded. Adding
period with an extra 10 dB weighting added on the equivalent
each interval during which this occurred shows that during the 60-minute measuring period the Llo was
sound levels occurring during night-time heoxcueres d(e2d2 :60 0m–i7n:u0t0es). (1/2 + 2S +t a2t i+s t1i1c/a2l =d e6s)c orri p1t0o pres rocfe tnrt aoffif thc en toimisee.. The calculation of Leq is more complex.
Leq is the constant, averageF sHoWuAn, 1d9 9l2evel, which over a period of time contains the same amount of sound
energy as the varying levels of the traffic noise. Leq for typical traffic conditions is usually about 3 dBA less
than the Llo for the same conditions. The Federal Highway Administration (FHW A) has established noise
impact criteria for different land uses close to highways. Some of the exterior criteria are illustrated below.
4
Land Use L1O Leq
Residential 70 dBA 67 dBA
Commercial 75 dBA 72 dBA
If a project causes a significant increase in the future noise level over the existing noise level, it is also
considered to have an impact.
What Can Be Done to Reduce Highway Noise?
Highway noise is being attacked with a three-part strategy: motor vehicle control, land use control, and highway
planning and design. The responsibilities for implementing these strategies must be shared by all levels of
government: Federal, State, and local. Often, local officials can most effectively solve specific noise problems
in their areas, as demonstrated in the U.S. Environmental Protection Agency's (EPA) Quiet Community and
Each Community Helps Others (ECHO) programs. The following two sections briefly describe how traffic noise
impacts can be reduced or prevented through efforts to obtain quieter vehicles and efforts to control future
development near highways. The remainder of this pamphlet focuses mainly on noise abatement in the
Federal-aid highway program.
Motor Vehicle Control
The first part of the strategy goes right to the source of traffic noise: the vehicles. For example, vehicles can be
designed with enclosures for the engine, fans that turn off when not needed, and better mufflers. Quieter
vehicles would bring about a substantial reduction in traffic noise along those roads and streets where no other
corrective measures are possible. The EP A has issued regulations placing a limit on the noise which new
trucks can make. In addition, many local and State governments have passed ordinances or laws requiring
existing vehicles to be properly maintained and operated. Unfortunately, due to limitations in technology, these
EP A regulations for new trucks and State and local regulations for maintenance of vehicles can only partially
reduce the noise created by traffic. The best that can be expected is a 5 to 10 dBA decrease in the noise level.
Where this is insufficient, other measures must be used. Land Use Control The second part of the strategy
calls for the control of future development. Sometimes, complaints about highway traffic come from occupants
of new homes built adjacent to an existing highway. Many of these highways were originally constructed
through undeveloped lands. There are several hundred thousand miles of existing highways in this country
bordered by vacant land which may some day be developed. Prudent land use control can help to prevent
many future traffic noise problems in these areas. Such controls need not prohibit development, but rather can
require reasonable distances between buildings and roads as well as "soundproofing" or other abatement
measures to lessen noise disturbances. Many local governments are working on land use control.
file://E:\11-SUT%20Sourcebook\02-modules\09-noise\resource%20materials\Highwa... 10-Sep-02