Alpine County, CA Noise Ordinances: Decibel Limits (2026)

Alpine County is one of the relatively few rural California counties with a true numeric, zone-based decibel standard. Under Alpine County Code Section 18.68.090(B), no activity may produce sound measured in excess of the following Leq(15) limits beyond parcel boundaries: Residential Neighborhood (RN) 65 dB(A); Residential Estates (RE) 60 dB(A); Institutional (INS) 70 dB(A); Planned Development (PD) 70 dB(A); Commercial Recreational (CR) 75 dB(A); and Commercial (C) 75 dB(A). The limits include all subcategories of those districts (such as RN-20 or RE-4), the (A) refers to the A-weighted scale, and the limits do not apply to parcel lines inside the interior of a building. 'Leq(15)' is defined as the average noise level measured over a fifteen-minute period. The code prescribes how to measure: a Type I or Type II sound level meter on the A-weighted scale, calibrated immediately before use with a certified calibrator and certified annually. An ambient-adjustment rule provides that where the measured background level already exceeds the standard, the limit is raised to the ambient level plus five decibels. Exemptions (construction in set hours, emergencies, daytime residential and commercial activity, public utilities, schools, garbage pickup, firearms) and exception permits modify when the limits apply, but the numbers themselves are fixed by zone.