2. Introduction
Noise can be defined as unwanted sound .
It can be defined as any sound that can produce an
undesirable effect to living especially human either
physiologically or psychologically or may interfere
with personal, social or group activities or work or
communication or rest or recreation or sleep. Noise is
measured by sound level meter.
3. Noise Measured
Normal conversation is about 60 dB, a lawn
mower is about 90 dB, and a loud rock
concert is about 120 dB.
In general, sounds above 85 are harmful,
depending on how long and how often you
are exposed to them
4. Sound Level Meter
Noise is measured by mean of sound level meter.
Measured in decibels (dB)
5. The meter is positioned in desired location with no
obstruction from sound source and the reading is
taken
6. Noise Standard
Area
code
Category of
area/zone
Limits in dB (A) Leq
Level of sound w.r.t. human hearing
Day time
6.00 am –
10.00 pm
Night time
10.00 pm –
6.00 am
A Industrial area 75 70
B Commercial area 65 55
C Residential area 55 45
D Silence zone
(100 metres around
hospitals, educational
institutions, courts,
religious places, etc)
50 40
The noise pollution (regulation and control) rules, 2000
7. Sources Of Noise Pollution
Traffic Noise including air traffic, road traffic sea and
inland water traffic – Traffic usually produce a lot of
noise , particularly in big cities and is responsible for
causing lot of nuisance to the society
The amount & type of noise produced by traffic is
largely dependent upon the type of traffic
Noise produce also depend upon the maintenance of
the automobile
8. Industries – Noise is essential by product of
industry, its intensity & nature being dependent upon
the type of industry.
9. Other miscellaneous sources of Noise :
It include Public address system ( Public functions,
Navratri Festival etc.)
Sirens (of industries, police or other purpose)
Shouting of hawkers ( ex. In market place )
Playing the children ( for ex. In a school, playground)
Military source : Noise of Bomb, grenade explosions,
tanks other vehicles. Missiles etc.
Construction Activities : Noise of different equipments
used for construction, in material & noise produce in
material handling
Fire cracks in Diwali
10. Noise Pollution Effects
Major effects
Loss of hearing – This loss is divided in to two part
Noise induced temporary threshold shift (NITTS)
– This is caused due to exposure to loud noise like
bursting of crackers . This can be recovered in
short period of time.
Noise induced Permenant Threshold shift
(NIPTS) – This occurs because of exposure to loud
noise for a long period of time.
Annoyance – This is subjective matter for
sound/Noise. Someone may like classical music but it
may annoy others. General annoyance is felt at
about 75 to 85 db
11. Health effects :
Effect on physical health : Audictory effect & Non
audictory effect
Auditory effect : They are grouped in to short time & long
time effects
Acoustic trauma is caused by a very high intensity
impulsive noise of about 150 dB or more from explosion
(i.e. bursting of crackers very near to the ear
Non-auditory effects : Exposure to a loud noise may
increase the pulse rate and blood pressure changes
Effect on mental health – Effect on mental health is less.
Lack of concentration at high noise level and mental
disorientation are some of the effect on mentle health
12. Interfere with communication – A person may face
the problem of trying to understand another person
talking to him /her in environment with high
background noise level
Background noise level can thus effect the efficiency
of offices, schools and other places where
communication is of vital importance
Working Efficiency – It is found to be decreased
drastically whenever a person is working in the noisy
environment.
13. Other effects
Sleep interference
Increased industrial accidents
Personal comfort interference
Property value degradation
Effect on wildlife
14.
15. Control of Noise Pollution
Proper maintenance & lubrication of machines can reduce
the noise
Sources of noise pollution like heavy vehicles, airports,
noise producing industries etc should be located away from
populated area
Silence zone should be created around residential areas,
educational institutes and hospitals
Noisy Machine should be installed in sound proof
chambers. Sound absorber s like glass, wool, porous panels,
perforated panels, tiles, carpets, curtain can be used.
Planting more trees having broad leaves which can absorb
sound
Noise pollution can be controlled by enacting stringent law
