WAC 173-58-060. Equipment variation allowances

Due to unavoidable variations in measurement sites and test instruments, the following allowances shall be made for the respective sound level meters: ± 1 dBA for Type 1 sound level meters ± 2 dBA for Type 2 sound level meters ± 1 dBA for Type 1 sound level meters ± 2 dBA for Type 2 sound level meters This tolerance value shall be applied, after all necessary calculations have been made, to the final reported sound level for the measured sound source.