Noise Pollution

Noise may not seem as harmful as the contamination of air or water, but it is a pollution problem that affects human health and can contribute to a general deterioration of environmental quality.Noise is undesirable and unwanted sound. Not all sound is noise. What may be considered as music to one person may be noise to another! It is not a substance that can accumulate in the environment like most other pollutants. Sound is measured in a unit called the 'decibel' (dB).There are several sources of noise pollution that contribute to both indoor and outdoor noise pollution. Noise emanating from factories, vehicles, and playing of loudspeakers during various festivals can contribute to outdoor noise pollution, while loudly played radio or music systems, and other electronic gadgets can contribute to indoor noise pollution. A study conducted by researchers from the New Delhi-based National Physical Laboratory show that noise generated by firecrackers (presently available in the market) is much higher than the prescribed levels. The permitted noise level is 125 decibels, as per the Environment (Protection) (second amendment) Rules, 1999.The differences between sound and noise is often subjective and a matter of personal opinion. There are, however, some very harmful effects caused by exposure to high sound levels. These effects can range in severity from being extremely annoying to being extremely painful and hazardous.

Decibel levels of common sounds dB  Environmental Condition

0  Threshold of hearing10  Rustle of leaves20  Broadcasting studio30  Bedroom at night40  Library50  Quiet office60  Conversational speech (at 1m)70  Average radio74  Light traffic noise90  Subway train

100  Symphony orchestra110  Rock band120  Aircraft takeoff146  Threshold of pain

Effects of noise pollution on physical health The most direct harmful effect of excessive noise is physical damage to the ear and the temporary or permanent hearing loss often called a 'temporary threshold shift' (TIS). People suffering from this condition are unable to detect weak sounds. However, hearing ability is usually recovered within a month of exposure. In Maharashtra, people living in close vicinity of Ganesh mandals that play blaring music for ten days of the Ganesh festival are usually known to suffer from this phenomenon. Permanent loss, usually called 'noise-induced permanent threshold shift' (NIPTS) represents a loss of hearing ability from which there is no recovery.Below a sound level of 80 dB hearing loss does not occur at all. However, temporary effects are

noticed at sound levels between 80 and 130 dB. About 50% of the people exposed to 95 dB sound levels at work will develop NIPTS and most people exposed to more than 105 dB will experience permanent hearing loss to some degree. A sound level of 150 dB or more can physically rupture the human eardrum.The degree of hearing loss depends on the duration as well as the intensity of the noise. For example, 1 hour of exposure to a 100 dB sound level can produce a TIS that may last for about one day. However, in factories with noisy machinery, workers are subjected to high sound l~vels for several hpurs a day. Exposure to 95 dB for 8 hours everyday for over a period of 10 years may cause about 15 dB of NIPTS. In addition to hearing losses, excessive sound levels can cause harmful effects on the circulatory system by raising blood pressure and altering pulse rates.

Effects of noise pollution on mental health: Noise can also cause emotional or psychological effects such as irritability, anxiety and stress. Lack of concentration and mental fatigue are significant health effects of noise. It has been observed that the performance of school children is poor in comprehension tasks when schools are situated in busy areas of a city and suffer from noise pollution.As noise interferes with normal auditory communication, it may mask auditory warning signals and hence increases the rate of accidents especially in industries. It can also lead to lowered worker efficiency and productivity and higher accident rates on the job.Thus, noise is just more than a mere nuisance or annoyance. It definitely affects the quality of life. It is therefore important to ensure the mitigation or control of noise pollution.

Permitted noise levels Ambient Noise Levels dB Zone   Day-time   Night-time

Silent Zone  50   40Residential Zone  55   45

Commercial Zone  65   55Industrial Zone  70   70

A standard safe time limit has been set for exposure to various noise levels. Beyond this 'safe' time continuing exposure over a period of a year will lead to hearing loss.

Duration  dB8 hours  904 hours  932 hours  961 hours  99

30 minutes  10215 minutes  1057 minutes  1084 minutes  1112 minutes  1141 minutes  117

30 seconds  120Instantaneous rupture of membrane  150

Noise-control techniquesThere are four fundamental ways in which noise can be controlled: reduce noise at the source, block the path of noise, increase the path-length, and protect the recipient. In general, the best control method is to reduce noise levels at the source.There are four fundamental ways in which noise can be controlled: reduce noise at the source, block the path of noise, increase the path-length, and protect the recipient. In general, the best control method is to reduce noise levels at the source.However, one of the best methods of noise source reduction is the regular and thorough maintenance of operating machinery. Noise levels at construction sites can be controlled using proper construction planning and scheduling techniques. Locating noisy air-compressors and other equipment away from the site boundary, along with creating temporary barriers to physically block the noise, can contribute to reducing noise pollution.Most of the vehicular noise comes from the movement of the vehicle tires on the pavement and wind resistance. However, poorly maintained vehicles can add to the noise levels. Traffic volume and speed also have significant effects on the overall sound. For example, doubling the speed increases

Introduction

The present generation and the coming generations have to solve three grave problems, namely, population poverty and pollution if they have to survive. Pollution being the most dangerous problem likes cancer in which death is sure but slow. Environment pollution is assuming dangerous proportions all through the globe and India is not free from this poisonous isease. This is the gift of modern living, industrialization and urbanization. Unless timely action is taken we have a forbid and bleak future for the world.

In chambers 21st Century Dictionary the definition of noise has undergone a change. Noise pollution stands carved out as phrase separately from noise. The two are defined as under:

Noise- a sound; a harsh disagreeable sound, or such sound; a din. Pollution- an excessive or annoying degree of noise in a particular area, e.g. from traffic, Industrial processes or aero plane engines.

Sources of Noise Pollution

Road Traffic Noise:-In the city, the main sources of traffic noise are the motors and exhaust system of autos , smaller trucks, buses, and motorcycles. This type of noise can be augmented by narrow streets and tall buildings, which produce a canyon in which traffic noise reverberates. Air Craft Noise: -Now-a-days , the problem of low flying military aircraft has added a new dimension to

community annoyance, as the nation seeks to improve its nap-of the- earth aircraft operations over national parks, wilderness areas , and other areas previously unaffected by aircraft noise has claimed national attention over recent years.Noise from railroads: - The noise from locomotive engines, horns and whistles, and switching and shunting operation in rail yards can impact neighboring communities and railroad workers. For example, rail car retarders can produce a high frequency, high level screech that can reach peak levels of 120 dB at a distance of 100 feet, which translates to levels as high as 138, or 140 dB at the railroad worker’s ear.Construction Noise:- The noise from the construction of highways , city streets , and buildings is a major contributor to the urban scene . Construction noise sources include pneumatic hammers, air compressors, bulldozers, loaders, dump trucks (and their back-up signals), and pavement breakers.Noise in Industry: - Although industrial noise is one of the less prevalent community noise problems, neighbors of noisy manufacturing plants can be disturbed by sources such as fans, motors, and compressors mounted on the outside of buildings Interior noise can also be transmitted to the community through open windows and doors, and even through building walls. These interior noise sources have significant impacts on industrial workers, among whom noise- induced hearing loss is unfortunately common.Noise in building: - Apartment dwellers are often annoyed by noise in their homes, especially when the building is not well designed and constructed. In this case, internal building noise from plumbing, boilers, generators, air conditioners, and fans, can be audible and annoying. Improperly insulated walls and ceilings can reveal the sound of-amplified music, voices, footfalls and noisy activities from neighboring units. External noise from emergency vehicles, traffic, refuse collection, and other city noises can be a problem for urban residents, especially when windows are open or insufficiently glazed.

Harmful Effects

On Human Being, Animal and Property: Noise has always been with the human civilization but it was never so obvious, so intense, so varied & so pervasive as it is seen in the last of this century. Noise pollution makes men more irritable. The effect of noise pollution is multifaceted & inter related. The effects of Noise Pollution on Human Being, Animal and property are as follows:

Annoyance:It creates annoyance to the receptors due to sound level fluctuations. The aperiodic sound due to its irregular occurrences causes displeasure to hearing and causes annoyance.Physiological effects:The physiological features like breathing amplitude, blood pressure, heart-beat rate, pulse rate, blood cholesterol are effected.Loss of hearing:Long exposure to high sound levels cause loss of hearing. This is mostly unnoticed, but has an

adverse impact on hearing function.Human performance:The working performance of workers/human will be affected as they'll be losing their concentration.Nervous system:It causes pain, ringing in the ears, feeling of tiredness, thereby effecting the functioning of human system.Sleeplessness:It affects the sleeping there by inducing the people to become restless and loose concentration and presence of mind during their activities.Damage to material :The buildings and materials may get damaged by exposure to infrasonic / ultrasonic waves and even get collapsed.

Environmental Laws Pertaining to Noise pollution

Noise Pollution Control Rule 2000 under Environment Protection Act 1996 :-

Further for better regulation for noise pollution There are The Noise Pollution ( Regulation and Control ) Rules, 2000 – in order to curb the growing problem of noise pollution the government of India has enacted the noise pollution rules 2000 that includes the following main provisions:-

The state government may categories the areas in the industrial or commercial or residential.The ambient air quality standards in respect of noise for different areas have been specified.State government shall take measure for abatement of noise including noise emanating from vehicular movement and ensure that the existing noise levels do not exceed the ambient air quality standards specified under these rules.An area not less than 100 m around hospitals educations institutions and court may be declare as silence are for the purpose of these rules.A loud speaker or a public address system shall not be used except after obtaining written permission from the authority and the same shall not be used at night. Between 10 pm to 6 am.A person found violating the provisions as to the maximum noise permissible in any particular area shall be liable to be punished for it as per the provision of these rules and any other law in force.

Noise Pollution Standards Selected BIS code books on noise pollution

BIS Code DescriptionIS-4954-1968 Noise abatement in town planning recommendationsIS-3098-1980 Noise emitted by moving road vehicles, measurementIS-10399-1982 Noise emitted by stationary road vehicles, methods of measurement IS-6098-1971  

Air borne noise emitted by rotating electrical machinery, method of measurement

IS-4758-1968 Noise emitted by machines, methods of measurements ofIS-3483-1965 Noise reduction in industrial buildings, code of practice for

IS-1950-1962 Sound insulation of non-industrial buildings, code of practiceIS-9167-1979 Ear protectors

Indian Standards for ambient noise levels 1

Area Noise Limits, Leq, dB (A)  Day Time 2 Night Time3

Silence zone 4 50 45Residential area 55 45Commercial area 65 55Industrial area 75 65

Ministry of Environment and Forest (MOEF) Guidelines vide Environment (Protection) Act, 1986 third amendment rules, dated 26/12/89 (Ref. 6)Day time from (600 hrs to 2100 hrs, IST)Night time from (2100 hrs to 600 hrs IST)Silence zone: Up to 100m around hospitals, educational institutions and courts. The zones are to be declared by competent authority. Use of vehicle horns, loud speakers and bursting of crackers shall be banned in these zones.

Damage risk criteria for hearing loss Occupational Safety & Health Administration (OSHA) regulations

Maximum allowable duration per day Sound pressure levelHours dB (A)8 906 924 953 972 1001.5 1021 1050.75 1070.5 1100.25 115

No exposure in excess of 115 dB(A) is permitted.

Scope Of Work

Conducting the noise pollution survey at Indoor and Outdoor Premises of the site.Identification of High Noise Area in and around the SiteIdentification of location which contribute high noise and monitoring time weighted average if necessaryRecommendations to take corrective action to reduce the noise on basis of the survey conducted.

Advisory support for Noise control in order to comply with set standards.Noise Data MappingTime Frame:- 1 Month, 2 Month, 3 Month depending on severity of Project