Pollution due to Noise:

Sound is an important means of communication,  but high levels of noise could damage hearing, and cause deterioration  in capacity  to concentrate on work. Noise is referred to as unwanted sound that is usually unpleasant. The loudness of  noise is measured in decibels (db). The quietness of a lonely place at night may be represented by, 20 db; a library where people are not supposed even to talk loudly, by 40 db; the sound level when you hear a radio broadcast, by  60 db; a factory or a motor-cycle may produce uncomfortable noise at 100 db, if you stand near a  jet engine of  the airlines it may be hard to bear the noise of  120  db level. High level of noise is harmful to man. Hearing loss begins with prolonged exposure (8 hours or more) to noise at 80-90 db or more. 

Can you  think of  some places where there is high level of noise? The level of noise is very high  in certain industries,  such as the ones dealing with iron and steel manufacture, motor vehicle production, metal products fabrication. printing and publishing, lumbering and wood products, and textile manufacturing. Busy streets in big towns, and the places near the railway tracks are so noisy  that if you were living there, you would hardly be able to sleep.

It is often said that noise pollution is different  from air, soil and water pollution.  let us see how? Noise pollution differs significantly  from air, soil and water pollution in the sense that it decays almost instantaneously and leaves no residues, whereas a majority of  pollutants of air, soil and water remain  as such for very long durations. Now  the question arises how can noise pollution be reduced? Maintenance  of machinery and automobiles, etc. in good condition reduces noise. Loudspeakers which blare music at night during celebrations of  festivals or marriages cause tremendous strain on the whole neighbourhood. Rules that already exists to stop such noise should be enforced by local administration. Planting of trees along roads also reduces noise levels in residential areas or if work places.