Full Description This Standard provides three primary methods for evaluating room noise: a survey method that employs the A-weighted sound level; an engineering method that employs expanded noise criteria (NC) curves; and a method for evaluating low-frequency fluctuating noise using room noise criterion (RNC) curves.
ASA S12.2-2019 history
2019ASA S12.2-2019 American National Standard for Criteria for Evaluating Room Noise.
2008ASA S12.2-2008 American National Standard Criteria for Evaluating Room Noise
1995ASA S12.2-1995 Criteria for Evaluating Room Noise ASA 115-1995; Erratum