ASA S12 9 PART 2-1992 American National Standard Quantities and Procedures for Description and Measurement of Environmental Sound Part 2 Measurement of Long-Term Wide-Area Sound《环境.pdf
Reaffirmed by ANSI April 21, 2008Reaffirmed byANSI on March 13, 2003ANSI/ASA S12.9-1992/Part 2 ( ) Reaffirmed by ANSI May 28, 2013