Environmental noise is the summary of noise pollution from outside, caused by transport, industrial and recreational activities.[1]
Noise is frequently described as 'unwanted sound', and, within this context, environmental noise is generally present in some form in all areas of human activity. The effects in humans of exposure to environmental noise may vary from emotional to physiological and psychological.[2]
Noise at low levels is not necessarily harmful; environmental noise can also convey a sense of liveliness in an area, and is not then always considered 'unwanted'. However, the adverse effects of noise exposure (i.e. noise pollution) could include: interference with speech or other 'desired' sounds, annoyance, sleep disturbance, anxiety, hearing damage and stress-related cardiovascular health problems.[3]
Weather-proof microphone attached to box containing sound level meter for environmental noise measurements
As a result, environmental noise is studied, regulated and monitored by many governments and institutions. This creates a number of different occupations. The basis of all decisions is supported by the objective and accurate measurement of noise. Noise is measured in decibels (dB) using a pattern-approved sound level meter. The measurements are typically taken over a period of weeks, in all weather conditions.
