NOISE & THERMAL POLLUTION

DINESH SHARMA 02710102714UDIT MISHRA 02910102714

ANUNAY SINHA 03010102714

NOISE POLLUTION

WHAT IS NOISE ?

Noise is an unpleasant / 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 Vs NOISE

SOUND

• Pleasant to hear• Constant pitch• Regular periodic motion• Produces meaningful

communication• Unit is Hertz (Hz)• Hz= cycle/sec.

NOISE

• Unpleasant to hear• Constantly varying pitch• No regular periodic motion• Produces no meaningful

communication• Unit is decibel (dB)• dB=10 log(intensity

measured/reference intensity)

Understanding noise levels

• Noise is measured in dB

• Threshold of hearing is 0 dB

• Sound of rocket launching is 180 dB

• Human ear tolerates up to 120 dB

• dB scale is logarithmic rather than linear

SOURCES OF NOISE POLLUTION• Chiller Operation• Compressor Operation• Street traffic • Constructions• Consumer products • Others more sources.

EFFECT OF NOISE POLLUTION

• Loud noises can cause hearing loss

• Long time exposure to a harmless noise can cause hearing

loss

• Damage from hearing loss is irreversible

• Noise induced hearing loss is preventable

EFFECT OF NOISE POLLUTION

• 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.

EFFECT OF NOISE TO INNER EAR• Hair cells in the inner ear transmit noise signals to the

brain.

Normal hair cells Noise-damaged hair cells

EFFECT OF INDUSTRIAL NOISE POLLUTION

• It can result into increase in blood pressure• Increased stress• Fatigue (Low Energy / Weakness)• Sleep disturbance• Annoyance (Irritation / Frustration)• Speech Problems• Aggression (Anger / Violent Behavior)• Anxiety (Nervousness / Disquiet)

DECIBEL SCALE

SOLUTIONS

Industrial Noise

1. Redesign industrial equipment 2. Screens and enclosures around machinery to obstruct noise

path. 3. Construction of sound proof rooms for noisy machines.4. Use shock absorbing materials.5. Use white noise machine6. Use mufflers or noise reducers7. Location of factories to be away from settlements.8. Use earpiece for workers

ROAD TRAFFIC NOISE

1. Use of better automobile silencers

2. Reduction in braking and acceleration by

ensuring smooth traffic flow

3. Use of noise barriers

4. Use of horns with jarring sounds to be banned

LEGISLATIONS ON NOISE CONTROL IN INDIA

1. Environmental (Protection) Act, 19862. Air (Prevention & Control of Pollution) Act, 19813. Factories Act, 19484. Motor Vehicles Act, 19885. Indian Penal Code – Sections 268, 290 & 2916. Criminal Procedure Code – Section 1337. Law of Torts8. Local Acts/Rules regulating loud speakers etc.

THERMAL POLLUTION

THERMAL POLLUTION• ADDITION OF EXCESS OF UNDESIRABLE HEAT TO WATER THAT MAKES IT HARMFUL TO MAN, ANIMAL OR AQUATIC LIFE

MAJOR CAUSES

• Nuclear power plants• Deforestation• Soil erosion

Nuclear Power Plants• Nuclear power plants use water as a cooling agent.• After the water is used, it is put back into a water supply at 9-

20oC warmer

This 1988 thermal image of the Hudson River highlights temperature changes caused by discharge of 2.5 billion gallons of water each day from the Indian Point power plant. The plant sits in the upper right of the photo — hot water in the discharge canal is visible in yellow and red, spreading and cooling across the entire width of the river. Two additional outflows from the Lovett coal-fired power plant are also clearly visible against the natural temperature of the water, in green and blue.

Waste Heat from Power Plants

Deforestation

•The decrease in vegetation increases the amount of light that hits the water, which increases the temperature of the water

•Deforestation also increases erosion

Soil Erosion

•Erosion makes the water muddy, which increases the light absorbed

Industrial Effluents

Discharged water from steam-electric power industry

using turbo generators will have a higher temperature

ranging from 6 to 9˚C than the receiving waterIn modern stations, producing 100 MW, nearly one

million gallons are discharged in an hour with increase

in temperature of the cooling water passing by 8 to 10 ˚C

Domestic sewageSewage is commonly discharged into lakes,

canals or streamsMunicipal sewage normally has a higher

temperature than the receiving waterIncrease in temperature of the receiving

water decreases the DO of water.The foul smelling gases increased in water

resulting in death of marine organisms

Effects of Increased Water Temperature• Thermal shock – aquatic life adapted to a certain water temperature

can go into shock when the temp is changed even 1 or 2 degrees.• Oxygen dissolved in water decreases• Increases the rate of photosynthesis, which increases the amount of

plant growth• Increases the metabolic rate of fish, which increases their need for

oxygen

Dissolved Oxygen vs Temp

Fish Oxygen Use vs. Temperature

Biotic Effects of Thermal Pollution

• Changes in the environment may also result in

• amigration of organisms to another, more suitable

• environment, and to in-migration of organisms that

• normally only live in warmer waters elsewhere. As

• a result one has the problem of compromising food

• chains of the old and new environments.

• Biodiversity can be decreased as a result.

Control of thermal pollution

• Cooling ponds, man-made bodies of water designed for cooling by evaporation, convection, and radiation

• Cooling towers, which transfer waste heat to the atmosphere through evaporation and/or heat transfer

• Cogeneration, a process where waste heat is recycled for domestic and/or industrial heating purposes

THANK YOU