A document that sets out how noise in a community is to be treated in terms of limits of level, duration, times of occurrence etc during the day. Different limits may apply to day times that to night times and between residential, industrial or commercial zones. Limits may be written in terms of absolute maximum levels not to be exceeded or in terms of the difference between the background level and the offending level. A person appointed to make such measurements makes measurements with an approved sound-measuring device usually on a property boundary line.