Westminster, CA Noise Ordinances: Decibel Limits (2026)

Westminster, an incorporated city, adopts its own quantitative noise standards rather than relying on the county. WMC Section 8.28.030 establishes Zone 1 (the entire city) and Zone 2 (property in the R2, R3, R4 and R5 multifamily land-use districts). Section 8.28.040 sets EXTERIOR limits measured at any point on the affected property: Zone 1 is 55 dB(A) during both 7 a.m.-10 p.m. and 10 p.m.-7 a.m.; Zone 2 is 60 dB(A) daytime and 55 dB(A) from 10 p.m. to 7 a.m. Section 8.28.050 sets INTERIOR limits measured within the affected dwelling at least four feet from walls, ceiling or floor nearest the source: Zone 1 is 55 dB(A) day / 45 dB(A) night, and Zone 2 is 60 dB(A) day / 50 dB(A) night. For any noise consisting of impact, simple-tone, speech or music content, each limit is reduced by 5 dB(A). The standards apply on a graduated duration basis: exceeding the limit is unlawful if it persists more than 30 minutes per hour, with progressively shorter allowances as the level rises (for example +5 dB(A) for more than 15 minutes, +10 for more than 5 minutes, +15 for more than 1 minute, and +20 dB(A) for any period). Measurement procedures are detailed in Section 8.28.070, and variances are handled by the county noise variance board under Section 8.28.080. These are the City of Westminster's own limits and govern within the city's incorporated boundaries.