Alameda, CA Noise Ordinances: Decibel Limits (2026)

Alameda uses a measured, cumulative-minutes standard rather than a single cap. Under AMC Section 4-10.4, Table I (single/multi-family residential, school, hospital, church, or public library) sets daytime (7 a.m.-10 p.m.) limits of 55 dB(A) for up to 30 min/hour, 60 for 15 min, 65 for 5 min, 70 for 1 min, and 75 dB(A) instantaneously; nighttime (10 p.m.-7 a.m.) limits are 5 dB(A) lower at each step (50/55/60/65/70). Table II for commercial property is 10 dB(A) higher than residential (e.g., 65 dB(A) daytime / 60 dB(A) nighttime for the 30-minute category). Each standard is reduced by 5 dB(A) for simple-tone noise, speech or music, or recurring impulsive noise. If ambient noise already exceeds a standard, the limit is raised to match ambient. Measurements (4-10.3) use an A-weighted sound level meter at slow response, with the mic 3-5 feet above ground and at least 4 feet from reflective surfaces, taken on the affected receiving property. A special 60 dB(A) limit applies to electrical substation transformers (4-10.4f). These are the City's standards, separate from Alameda County's Chapter 6.60.