Noise pollution, also known as environmental noise or sound pollution,
is the propagation of noise with harmful impact on the activity of
human or animal life. The source of outdoor noise worldwide is mainly
caused by machines, transport, and propagation systems. Poor urban planning
may give rise to noise disintegration or pollution, side-by-side
industrial and residential buildings can result in noise pollution in
the residential areas. Some of the main sources of noise in residential
areas include loud music, transportation (traffic, rail, airplanes, etc.), lawn care maintenance, construction, electrical generators, explosions, and people. Documented problems associated with urban environment noise go back as far as ancient Rome.
Noise is measured in Decibel (dB). Noise pollution associated with
household electricity generators is an emerging environmental
degradation in many developing nations. The average noise level of
97.60 dB obtained exceeded the WHO value of 50 dB allowed for residential areas. Research suggests that noise pollution is the highest in low-income and racial minority neighborhoods.
High noise levels can contribute to cardiovascular effects in humans and an increased incidence of coronary artery disease.
In animals, noise can increase the risk of death by altering predator
or prey detection and avoidance, interfere with reproduction and
navigation, and contribute to permanent hearing loss.
While the elderly may have cardiac problems due to noise, according to
the World Health Organization, children are especially vulnerable to
noise, and the effects that noise has on children may be permanent.
Noise poses a serious threat to a child's physical and psychological
health, and may negatively interfere with a child's learning and
behavior.
Health
Humans
Noise level from a leaf blower using NIOSH Sound Level Meter app
Noise pollution affects both health and behavior. Unwanted sound
(noise) can damage physiological health. Noise pollution is associated
with several health conditions, including cardiovascular disorders, hypertension, high stress levels, tinnitus, hearing loss, sleep disturbances, and other harmful and disturbing effects. According to a 2019 review of the existing literature, noise pollution was associated with faster cognitive decline.
Across Europe, according to the European Environment Agency,
an estimated 113 million people are affected by road traffic noise
levels above 55 decibels, the threshold at which noise becomes harmful
to human health by the WHO's definition.
A sound level meter, is one of the main tools for measuring sounds in the environment and the workplace
Sound becomes unwanted when it either interferes with normal
activities such as sleep or conversation, or disrupts or diminishes
one's quality of life. Noise-induced hearing loss can be caused by prolonged exposure to noise levels above 85 A-weighted decibels. A comparison of Maaban
tribesmen, who were insignificantly exposed to transportation or
industrial noise, to a typical U.S. population showed that chronic
exposure to moderately high levels of environmental noise contributes to
hearing loss.
Noise exposure in the workplace can also contribute to noise-induced hearing loss and other health issues. Occupational hearing loss is one of the most common work-related illnesses in the U.S. and worldwide.
It is less clear how humans adapt to noise subjectively.
Tolerance for noise is frequently independent of decibel levels. Murray
Schafer's soundscape research was groundbreaking in this regard. In his
work, he makes compelling arguments about how humans relate to noise on a
subjective level, and how such subjectivity is conditioned by culture.
Schafer also notes that sound is an expression of power, and as such,
material culture (e.g., fast cars or Harley Davidson motorcycles with
aftermarket pipes) tend to have louder engines not only for safety
reasons, but for expressions of power by dominating the soundscape with a
particular sound. Other key research in this area can be seen in Fong's
comparative analysis of soundscape differences between Bangkok,
Thailand and Los Angeles, California, US. Based on Schafer's research,
Fong's study showed how soundscapes differ based on the level of urban
development in the area. He found that cities in the periphery have
different soundscapes than inner city areas. Fong's findings tie not
only soundscape appreciation to subjective views of sound, but also
demonstrates how different sounds of the soundscape are indicative of
class differences in urban environments.
Noise pollution can have negative affects on adults and children on the autistic spectrum. Those with Autism Spectrum Disorder (ASD) can have hyperacusis, which is an abnormal sensitivity to sound.
People with ASD who experience hyperacusis may have unpleasant
emotions, such as fear and anxiety, and uncomfortable physical
sensations in noisy environments with loud sounds.
This can cause individuals with ASD to avoid environments with noise
pollution, which in turn can result in isolation and negatively affect
their quality of life. Sudden explosive noises typical of
high-performance car exhausts and car alarms are types of noise
pollution that can affect people with ASD.
Wildlife
Noise
can have a detrimental effect on animals, increasing the risk of death
by changing the delicate balance in predator or prey detection and
avoidance, and interfering the use of the sounds in communication,
especially in relation to reproduction and in navigation. These effects
then may alter more interactions within a community through indirect (“domino”) effects. Acoustic overexposure can lead to temporary or permanent loss of hearing.
European robins
living in urban environments are more likely to sing at night in places
with high levels of noise pollution during the day, suggesting that
they sing at night because it is quieter, and their message can
propagate through the environment more clearly. The same study showed that daytime noise was a stronger predictor of nocturnal singing than night-time light pollution,
to which the phenomenon often is attributed. Anthropogenic noise
reduced the species richness of birds found in Neoptropical urban parks.
Zebra finches
become less faithful to their partners when exposed to traffic noise.
This could alter a population's evolutionary trajectory by selecting
traits, sapping resources normally devoted to other activities and thus
leading to profound genetic and evolutionary consequences.
Underwater noise pollution due to human activities is also
prevalent in the sea. Cargo ships generate high levels of noise due to
propellers and diesel engines. This noise pollution significantly raises the low-frequency ambient noise levels above those caused by wind.
Animals such as whales that depend on sound for communication can be
affected by this noise in various ways. Even marine invertebrates, such
as crabs (Carcinus maenas), have been shown to be negatively affected by ship noise.
Larger crabs were noted to be negatively affected more by the sounds
than smaller crabs. Repeated exposure to the sounds did lead to acclimatization.
Higher ambient noise levels also cause animals to vocalize more loudly, which is called the Lombard effect. Researchers have found that humpback whales' song lengths were longer when low-frequency sonar was active nearby.
Noise pollution may have caused the death of certain species of whales that beached themselves after being exposed to the loud sound of military sonar.
Noise control
The sound tube in Melbourne, Australia is designed to reduce roadway noise without detracting from the area's aesthetics.
A man inserting an earplug in his ear to reduce the noise exposure
The Hierarchy of Controls concept is often used to reduce noise in
the environment or the workplace. Engineering noise controls can be used
to reduce noise propagation and protect individuals from overexposure.
When noise controls are not feasible or adequate, individuals can also
take steps to protect themselves from the harmful effects of noise
pollution. If people must be around loud sounds, they can protect their
ears with hearing protection (e.g., ear plugs or ear muffs). In recent years, Buy Quiet
programs and initiatives have arisen in an effort to combat
occupational noise exposures. These programs promote the purchase of
quieter tools and equipment and encourage manufacturers to design
quieter equipment.
Noise from roadways and other urban factors can be mitigated by urban planning and better design of roads. Roadway noise can be reduced by the use of noise barriers, limitation of vehicle speeds, alteration of roadway surface texture, limitation of heavy vehicles,
use of traffic controls that smooth vehicle flow to reduce braking and
acceleration, and tire design. An important factor in applying these
strategies is a computer model for roadway noise, that is capable of addressing local topography, meteorology,
traffic operations, and hypothetical mitigation. Costs of building-in
mitigation can be modest, provided these solutions are sought in the
planning stage of a roadway project.
Aircraft noise can be reduced by using quieter jet engines. Altering flight paths and time of day runway has benefited residents near airports.
Legal status
Up until the 1970s governments tended to view noise as a "nuisance" rather than an environmental problem.
Many conflicts over noise pollution are handled by negotiation
between the emitter and the receiver. Escalation procedures vary by
country, and may include action in conjunction with local authorities,
in particular the police.
India
Noise pollution is a major problem in India. The government of India has rules and regulations against firecrackers and loudspeakers, but enforcement is extremely lax. Awaaz Foundation
is a non-governmental organization in India working to control noise
pollution from various sources through advocacy, public interest
litigation, awareness, and educational campaigns since 2003.
Despite increased enforcement and stringency of laws now being
practised in urban areas, rural areas are still affected. The Supreme
Court of India had banned playing of music on loudspeakers after 10pm.
In 2015, The National Green Tribunal directed authorities in Delhi to
ensure strict adherence to guidelines on noise pollution, saying noise
is more than just a nuisance as it can produce serious psychological
stress. However, implementation of the law continues to remain poor.
Sweden
How noise
emissions should be reduced, without the industry being hit too hard,
is a major problem in environmental care in Sweden today. The Swedish Work Environment Authority
has set an input value of 80 dB for maximum sound exposure for eight
hours. In workplaces where there is a need to be able to converse
comfortably the background noise level should not exceed 40 dB. The government of Sweden has taken soundproofing and acoustic absorbing actions, such as noise barriers and active noise control.
United Kingdom
Figures compiled by rockwool, the mineral wool insulation manufacturer, based on responses from local authorities to a Freedom of Information Act (FOI) request reveal in the period April 2008 – 2009 UK councils
received 315,838 complaints about noise pollution from private
residences. This resulted in environmental health officers across the UK
serving 8,069 noise abatement
notices or citations under the terms of the Anti-Social Behaviour
(Scotland) Act. In the last 12 months, 524 confiscations of equipment
have been authorized involving the removal of powerful speakers, stereos
and televisions. Westminster City Council
has received more complaints per head of population than any other
district in the UK with 9,814 grievances about noise, which equates to
42.32 complaints per thousand residents. Eight of the top 10 councils
ranked by complaints per 1,000 residents are located in London.
United States
The Noise Control Act
of 1972 established a U.S. national policy to promote an environment
for all Americans free from noise that jeopardizes their health and
welfare. In the past, Environmental Protection Agency coordinated all federal noise control activities through its Office of Noise Abatement and Control. The EPA
phased out the office's funding in 1982 as part of a shift in federal
noise control policy to transfer the primary responsibility of
regulating noise to state and local governments. However, the Noise
Control Act of 1972 and the Quiet Communities Act of 1978 were never
rescinded by Congress and remain in effect today, although essentially
unfunded.
The Federal Aviation Administration (FAA) regulates aircraft noise
by specifying the maximum noise level that individual civil aircraft
can emit through requiring aircraft to meet certain noise certification
standards. These standards designate changes in maximum noise level
requirements by "stage" designation. The U.S. noise standards are
defined in the Code of Federal Regulations (CFR) Title 14 Part 36 –
Noise Standards: Aircraft Type and Airworthiness Certification (14 CFR
Part 36). The FAA also pursues a program of aircraft noise control in cooperation with the aviation community. The FAA has set up a process to report aviation-related noise complaints for anyone who may be impacted by Aircraft noise.
The Federal Highway Administration (FHWA) developed noise regulations to control highway noise
as required by the Federal-Aid Highway Act of 1970. The regulations
requires promulgation of traffic noise-level criteria for various land
use activities, and describe procedures for the abatement of highway
traffic noise and construction noise.
The Department of Housing and Urban Development
(HUD) noise standards as described in 24 CFR part 51, Subpart B
provides minimum national standards applicable to HUD programs to
protect citizen against excessive noise in their communities and places
of residence. For instance, all sites whose environmental or community
noise exposure exceeds the day night average sound level (DNL) of 65
(dB) are considered noise-impacted areas, it defines "Normally
Unacceptable" noise zones where community noise levels are between
65–75 dB, for such locations, noise abatement and noise attenuation
features must be implemented. Locations where the DNL is above 75 dB are
considered "Unacceptable" and require approval by the Assistant
Secretary for Community Planning and Development.
The Department of Transportation's Bureau of Transportation Statistics has created a National Transportation Noise Map
to provide access to comprehensive aircraft and road noise data on
national and county-level. The map aims to assist city planners, elected
officials, scholars, and residents to gain access to up-to-date
aviation and Interstate highway noise information.
States and local governments typically have very specific statutes on building codes, urban planning,
and roadway development. Noise laws and ordinances vary widely among
municipalities and indeed do not even exist in some cities. An ordinance
may contain a general prohibition against making noise that is a
nuisance, or it may set out specific guidelines for the level of noise
allowable at certain times of the day and for certain activities.
New York City instituted the first comprehensive noise code in 1985. The Portland
Noise Code includes potential fines of up to $5000 per infraction and
is the basis for other major U.S. and Canadian city noise ordinances.
