unwanted sound but this is subjective definition as one man’s sound may be another man’s noise.1 Physically there is no distinction between sound and noise. Sound is a sensory perception and the complex pattern of sound waves is labeled noise, music, speech etc. Environmental noise is a common cause of hearing loss in industrialized societies. When the noise exposure causing hearing loss is present in the workplace, it is referred to as occupational noise induced hearing loss (NIHL). Community noise