Acoustic noise is any sound in the acoustic domain, either deliberate (music, speech, etc.) or unintended. It is important to recognise that the term "noise" is also used to refer to other, non-audible forms, especially in electronics and in the radio/radar spectrum.
Environmental noise is the comprehensive study of acoustic phenomena in the human environment which involve unwanted sound. The principal sources of environmental noise are surface motor vehicles, aircraft, trains and industrial sources. These noise sources expose millions of people to noise pollution that creates not only annoyance, but also significant health consequences such as elevated incidence of hearing loss and cardiovascular disease. There are a variety of mitigation strategies and controls available to reduce sound levels including source intensity reduction, land use planning strategies, noise barriers and sound baffles, time of day use regimens, vehicle operational controls and architectural acoustics design measures.
Laws governing noise
Environmental noise is governed by laws and standards which set maximum recommended levels of noise for specific land uses, such as residential areas, areas of outstanding natural beauty, or schools. These standards usually specify measurement using a weighting filter, most often A-weighting.