Washington State law (WAC 173-60-040) sets maximum allowable noise levels based on the zoning class of both the noise source and the receiving property, ranging from 55 to 70 dBA, with nighttime limits reduced by 10 dBA for residential areas between 10 p.m. and 7 a.m. Short-duration noise spikes are permitted, allowing up to 15 dBA above the limit for no more than 1.5 minutes per hour. Enforcement is complaint-driven, measured at the receiving property, and each 24-hour period of violation counts as a separate offense under RCW 70.107.050.Open full document
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Washington Administrative Code sections establishing maximum permissible environmental noise levels based on Environmental Designation for Noise Abatement (EDNA) classifications, with adjustments for nighttime hours and short-duration exceedances. Also includes the enforcement policy requiring noise measurement with a sound level meter at the receiving property, complaint-based enforcement, and treating each 24-hour period of violation as a separate offense.