ANSI/ASA S12.9-1992 (R2003)

Vendor Note: This standard is the second in a proposed series of parts concerning description and measurement of outdoor environmentalsound. This standard describes recommended procedures for measurement of long-term, time-average environmental soundoutdoors at one or more locations in a community for environmental assessment or planning for compatible land uses and forother purposes such as noise prediction validation and regulation. Sound may be produced by one or more separate,distributed sound sources such as a highway, factory, or airport, or by all contributing sound sources. For spatial or temporalsamples of environmental sound in a community, requirements are given for the number of sound-measurement locations andthe duration of the sound-sampling intervals needed to obtain average values for long-term environmental sound levels that arewithin stated accuracy limits for Class A, Class B, or Class C measurements. The purpose of this standard is to provide for acommonality for measurements of outdoor environmental sound as it may affect people in and around dwellings.