Santa Clara County, CA Noise Ordinances: Decibel Limits (2026)

The County's outdoor noise limits in Section B11-152 of Division B11, Chapter VIII apply to all property within any zoning district and are based on the receiving land use category. Measured at the receiving property, the maximum permissible exterior noise levels are: One- and Two-Family Residential - 55 dBA from 7:00 a.m. to 10:00 p.m. and 45 dBA from 10:00 p.m. to 7:00 a.m.; Multiple-Family Dwelling - 50 dBA at night (10 p.m.-7 a.m.); Residential Public Space - 55 dBA daytime; Commercial - 65 dBA daytime and 60 dBA at night; Light Industrial - 70 dBA any time; Heavy Industrial - 75 dBA any time. If the offending noise contains a steady audible tone (whine, screech or hum) or contains music or speech conveying informational content, the applicable limit from the table is reduced by 5 dB. The ordinance also addresses specific equipment: under the prohibited-acts provision, air conditioning and air-handling equipment may not generate noise exceeding 45 dBA at any point on a neighboring residential property line, or 40 dBA at the center of a neighboring patio or outside the nearest living-area window. Interior noise standards are addressed in Section B11-153. These limits apply only to unincorporated Santa Clara County.