ASTM E477 – 13 Laboratory Measurements of Acoustical and Airflow Performance of Duct Liner Materials and Prefabricated Silencers
ASTM E477–13 explains the laboratory testing of some of the acoustical properties of sound attenuating devices. Basically, it tests the performance of the specimen in well-defined and controlled conditions. The values stated in SI units are to be considered as standard.
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