An Area Source is any source of Air Pollution that is released over a relatively small area but which cannot be classified as a point source. Such sources may include vehicles and other small engines, small businesses and household activities, or biogenic sources such as a forest that releases hydrocarbons.
Other /More definition:
An area source is a stationary source that emits small amounts of air pollution. Wood-burning stoves and dry cleaners are two examples of area sources.
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