Although noise, commonly defined as unwanted sound, is a widely recognized form of pollution, it is very difficult to measure because the discamfort experienced by different individuals is highly subjective and, therefore, variable Exposure to lower levels of noise may be slightly irritating, whereas exposure to higher levels may actually cause hearing loss. Particularly in congesled urban areas, the noise produced as a byproduct of our advancing technology causes physical and psychological harm. and detracts from the quality of life r hose who are exposed to it.