Noise pollution refers to unwanted sounds that penetrate the environment. Sources of noise pollution include domestic activities, natural sounds, commercial activities, industrial operations, and transportation. The World Health Organization recommends maximum noise levels of 45 dB during the day and 35 dB at night. Excessive noise can cause annoyance, physiological effects, hearing loss, reduced human performance, sleeplessness, and damage to materials. Prevention of noise pollution involves creating noise barriers, restricting loud sounds at night, maintaining vehicles, and planting green spaces.

1. s
NOISE POLLUTION
SINTO KADA- LOYOLA COLLEGE, TRIVANDRUM

2. What is Pollution?
The introduction into the environment,
by people, of substances or energy
liable to cause harm to living creatures
or ecological systems.

3. What about Sound & Noise?
In simple terms, noise is unwanted
sound. Sound is a form of energy
which is emitted by a vibrating body
and on reaching the ear causes the
sensation of hearing through nerves.
Sounds produced by all vibrating
bodies are not audible. The frequency
limits of audibility are from 20 HZ to
20,000 HZ.

4. Sound Transmission

5. What is decibel?

6. How to measure sound?

7. Noise pollution
Any unwanted sound that
penetrates the environment is
noise pollution.
In general noise pollution refers
to any noise irritating to one's
ear which comes from an
external source.

8. Sources of Noise

Domestic (movement of utensils, cutting and
peeling of
fruits/vegetables etc.)

Natural (shores, birds/animal shouts, wind
movement, sea tide movement, water falls etc.)

commercial (vendor shouts, automobiles,
airplanes, marriages, laboratory, machinery etc.)

Industrial (generator sets, boilers, plant
operations,trolley movement, transport vehicles,
pumps, motors etc.)

9. W.H.O. (World Health Organization) has prescribed
optimum noise level as 45 dB by day and 35 dB by night.
Anything above 80 dB is hazardous

12. FIRE WORKS

13. Exhaust Pipes-Magnaflow
Boom Cars, Jake Brake Device

15. Noise contours around an
airport calculated using INM
(Integrated Noise Modeling)
based on previous noise
measurements
55 - 60 dB = Light blue
60 - 70 dB = Dark blue
70 - 75 dB = Red
75 - 80 dB = Green
80 - 85 dB = Yellow
> 85 dB = Pink
Airport Noise

16. OUR LEGISLOATION

18. Why bother about noise?

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.

19. 
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 nfrasonic / ultrasonic waves
and even get collapsed.

21. There are about 25000 hair cells in our
ear which create wave in our ear,
responding to different levels of
frequencies.
With increasing levels of sound the cells
get destroyed decreasing our ability to
hear the high frequency sound.

22. Be cautious!

Blood pressure rise of 5 to 10 mm
Hg on 8 hrs of exposure to even 70 db
of sound level.

Hearing loss begins at 80- 90 db A
140 db A is painful and 180 db A can
even kill a person.

Amplified rock music is 120 db A.

Most of the electronic vehicles and
motors are above 80 db A level.

23. Prevention and control of
noise pollution
• Noise abatement measures include creating
noise mounds, noise attenuation walls and
well maintained roads and smooth surfacing of
roads.
• Power tools, very loud music and land movers,
public functions using loudspeakers, etc should
not be permitted at night. Use of horns, alarms,
refrigeration units, etc. is to be restricted. Use of
fire crackers which are noisy and cause air
pollution should be restricted.

24. 
Air traffic noise can be reduced by
appropriate insulation and introduction of
noise regulations for take off and landing of
aircrafts at the airport.
• Industrial noises can be reduced by sound
proofing equipment like generators and
areas producing lot of noise.
• A green belt of trees is an efficient noise
absorber.

25. • Power tools, very loud music and land
movers, public functions using
loudspeakers, etc should not be permitted at
night. Use of horns, alarms, refrigeration
units, etc. is to be restricted. Use of fire
crackers which are noisy and cause air
pollution should be restricted.
• Road traffic noise can be reduced by better
designing and proper maintenance of
vehicles.
• A green belt of trees is an efficient noise

27. THANK YOU