Noise pollution may be defined as the state of discomfort and restlessness to human beings caused by unwanted high intensity sound (noise). It is of both natural and artificial type. Former is caused by natural sources like cloud thunder, hailstorms, wanderlust, avalanches and landslides etc. Latter is the outcome of human activities like running of ma?shines, automobiles, aircrafts, radios televisions, exhaust-fans, lawn-movers, blowing of sirens, loud-speakers, and organizing cultural programs, dance, and music etc.
It is the artificial noise pollution, which is increasing due to growing urban and industrial activities and is a matter of serious concern. Noise level is measured in terms of decibel (db) which is the unit of measurement of intensity of sound. A noise of zero db on the decibel scale represents the faintest sound audible to human ear while that of 1 80 db shows the sound of large rocket engine. In general, noise above 70 db is harmful to human beings.
In India noise pollution is growing in recent years due to increase in industrial, urban, transport and construction activities. A number of studies have revealed that noise pollution is a greater men?ace in most of the million cities of India characterized with high traffic density and *industrial active-,ties. However, the level of pollution varies in AC. Accordance with the location, time, population density and functions of the city. The study of Kanata (Kumara, 1982), Iambi and Achaean have revealed common features, I. . High noise level in the areas located close to aerodromes, railway stations, us terminals, industrial establishments, busy markets, high density traffic routes and high population den-sits clusters. Loudspeakers and traffic noise is the great nuisance in the Indian cities. The level of pollution increases during festivals, cultural pro-grammas, elections, national festivities and victories and traffic jams. Most of our cities have higher level of noise pollution than the permissible limit of 60-70 db.
Delhi (89 db), Kola (87 db), Iambi (85 db), Achaean (82 db), Koch (80 db), Modular (75 db), Nagger (75 B) and Authoritarianism (70 db) may be cited as examples. A study by the Environmental Monitoring Laboratory of the Indus?trial Toxicology Research Centre (Locknut) has shown that noise level is higher than 90 db near Hazarding crossing, King George Medical Cool. Leg, Mauritania, Royal Hotel crossing, Gold Darwin, NASA Handhold, Charge railway station, Alaskan, Amphibian and Sad crossing.
Continuous and prolonged exposure to noise pollution causes several disorders and ailments in human beings which angels from mild annoyance, mental tension, headache, fatigue, irritation, high blood pressure, stomach trouble, psychological problems, low working efficiency, and traffic accidents to permanent deafness. According to a study conducted in five southern cities including Achaean, Combaters, Modular, Koch and Authoritarianism to find out the Noise Induced Hearing Loss (NAIL) among the workers in the textile, automobile, Oil, fertilizers and chemical industries, one out of every four work-errs suffered from incurable NAIL.