Encyclopaedia of Environmental Science and Technology

Noise is the effect on the ear, of a wave like motion of an elastic medium, caused by vibration, which impinge on the ear drum and set up a nervous disturbance. It is unwanted and undesirable sound in the wrong place and at the wrong time. Sound from various sources like buses, racing cars and trucks, silencer less motorbikes, myriad of homs, vibrating foundries and lathes, blaring stereos and loudspeakers, the sonic boom from supersonic aircrafts and space rockets ensure shatter peace of mind and sleepless nights. Noise pollution affects human beings at three levels: Auditory effects, non-auditory, effects and physiological effects. High intensity noise cause annoyance and hearing damage, stimulation of reception in skin and pain,nausea and vomiting, dizziness and insanity, and car drum rupture. The mechanism of hearing loss result from short intense exposure which damage Organ of Corti. Surveys on prevalence of noise induced hearing loss have been done in some cities of our country. These surveys indicate that deafness may be due to perforation of the tympanic membrane.