ambient sound level (ASL)

Ambient Sound Level(ASL) is a sound level composed of various background sounds and is not directly interpretable.

Background noise can be traffic noise from motor vehicles, trains, or airplanes; non-neighborhood noise from people and machinery; noise from utility lines such as the hiss in water pipes; noise from household appliances and consumer electronics devices; industrial noise; etc.

Ambient sound level can be disturbing or very disturbing and can exceed the normal entertainment level. The perception of the disturbance level is subjective; absolute worst-case values do not exist. A measurement of the ambient sound level should only take place under representative conditions.