Noise Pollution

Noise Pollution

• No one can escape the unwanted sound that is called noise-a disturbance to our environment escalating so rapidly that it is becoming one of the major threats to the quality of human life.

• Noise pollution is defined as - unwanted, unpleasant sound that causes discomfort of human beings. Noise or sound is measured in decibal (dB).

• In homes, especially in developed countries, but also in big cities of developing countries more and more power gadgets constitute additional sources of noise. The effect of these multiple causes of noise can be cumulative.

• Noise exposure at work is added at home during leisure activities. Slowly, insensibly, man seems to accept noise-and the physiological and psychological deterioration that accompanies it-as an inevitable part of his life.

• Because noise does not pose as obvious and immediate a danger to health as polluted water or air, public wareness of noise and public commitment to noise reduction have been modest.

• Major differences between noise and other forms of pollution are as follows :

1. Noise is everywhere; it is not as easy to control as the sources of water and air pollution.

2. Although certain effects of noise, like those of many other pollutants, accumulate in the organism, if noise pollution were to cease there would be no noise residual in the environment, as there would be in the case of water and air pollutants.

3. Unlike air and water pollution, the effects of noise are felt only close to the source.

4. An essential awareness of noise and motivation to reduce the problem are not present ; people are more likely to complain and demand political action about air or water pollution than about noise.

5. Finally, noise is not likely to have genetic effects, while some form of air and water pollution, such as radioactive pollution, can cause genetic effects. 

1. Sources / Causes of Noise Pollution

• All the noise sources can be categorized into three types

1. Industrial noise 2. Transport noise 3. Domestic noise

1. Industrial noise : Industrial noise sources are - steel industry, textile industry, power generation, oil refineries generate huge amount of noise.

2. Transport noise : Traffic is considered to generate most annoying kind of noise. Road traffic, rail traffic and air traffic, all contribute to transport noise.

3. Domestic noise : Domestic noise sources are - household gadgets such as mixer, washing machine, refrigerator, air conditioners, vacuum cleaners and recreational noise (TV, radio) etc.

2. Effects of Noise Pollution

• Noise pollution severely affects human health. Various health problems are being reported because of noise pollution, such as -

i) Neurological disorder

ii) Anxiety

iii) Mental distress

iv) Heartattacks

v) Pathological disorder

vi) Deafiness/Impairment of hearing

vii) Sleeplessness.

• Ultrasonic sound affects digestive, respiratory cardio vascular systems and semicircular canals of the internal ear. The heart-beat rate is also affected.

• Because of loud and sudden noise brain also get adversely affected. People are subject to psychiatric illness.

3. Control Measures of Noise Pollution

1. Source control

Source control involves source modification such as :

Acoustic treatment to machine surface.

Change in machine design.

Controlling vibration of machines.

Applying proper lubrication of machine.

2. Transmission path intervention

Keeping noise source in insulating enclosure.

Constructing sound proof rooms.

3. Receptor control

This includes protection of receiver by altering the work schedule.

Using earplugs where abnormal noise is produced.

Dissipation and deflection of noise.

4. Banning noise polluting vehicles.

5. Plantation of trees on road side and near building can absorb noise.

6. Enforcing noise pollution control act.

7. Educating people about noise pollution and its consequences.

4. Ambient Noise Level

• Ambient noise levels at different zones are listed here