GB/T 6881-2023 Active

This document describes a method for determining the sound power level and sound energy level of noise sources by measuring the sound pressure level in a reverberation chamber. The sound power level (or sound energy level in the case of burst sound or transient noise) generated by the noise source is calculated using the measured sound pressure level, including corrections for differences between the meteorological conditions at the test site during the test and the meteorological conditions corresponding to the reference characteristic impedance. This document provides the measurement and calculation process for determining the sound power level and sound energy level using direct and comparative methods. Typically, the measurement frequency range includes 1/3 octave bands with a center frequency of 100 Hz to 10,000 Hz. Appendix E provides guidance on applying the specified method to a lower frequency range. This document cannot be used for 1/3 octave frequency ranges above 10,000 Hz.