本美国国家标准规定了计算声音衰减的工程方法 在户外传播期间，以预测距离 来源多种多样。该方法预测等效连续A加权声压级（as 如ISO 1996第1至3部分所述），在有利于传播的气象条件下 已知声发射源。

This American National Standard specifies an engineering method for calculating the attenuation of sound during propagation outdoors in order to predict the levels of environmental noise at a distance from a variety of sources. The method predicts the equivalent continuous A-weighted sound pressure level (as described in parts 1 to 3 of ISO 1996) under meteorological conditions favorable to propagation from sources of known sound emission.