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NOISE POLLUTION

SINTO KADA- LOYOLA COLLEGE, TRIVANDRUM

What is Pollution?

The introduction into the environment, by people, of

substances or energy liable to cause harm to living creatures or

ecological systems.

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.

Sound Transmission

What is decibel?

How to measure sound?

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.

Sources of Noise Domestic (movement of utensils, cutting and

peeling offruits/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.)

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

FIRE WORKS

Exhaust Pipes-Magnaflow

Boom Cars, Jake Brake Device

Noise contours around an airport calculated using INM (Integrated Noise Modeling) based on previous noise measurements

55 - 60 dB = Light blue60 - 70 dB = Dark blue70 - 75 dB = Red75 - 80 dB = Green80 - 85 dB = Yellow> 85 dB = Pink

Airport Noise

OUR LEGISLOATION

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.

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.

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.

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. High noise levels may interfere with the natural

cycles of animals, including feeding behavior, breeding rituals and migration paths.

Prevention and control of noise pollution

• Noise abatement measures include creating noise mounds, noise attenuation walls andwell 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.

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 andareas producing lot of noise.• A green belt of trees is an efficient noise absorber.

• 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 absorber.

THANK YOU