Alhambra, CA Noise from Specific Sources: Generator Noise (2026)

270(E), the city's standards for telecommunication facilities single out backup generators as a noise source needing extra control beyond ordinary siting review. 02, which cap noise at 55 dBA in Residential zones, 60 dBA in Mixed-Use zones and 70 dBA in Commercial zones, measured four feet from the nearest wall, ceiling or floor of an affected structure with windows and doors closed. Beyond that numeric ceiling, the telecom-facility rule adds an operating restriction found nowhere else in the noise code: a backup generator at a cell tower, equipment cabinet or similar facility may run only during an actual power outage or for scheduled testing and maintenance, and that testing must be scheduled and conducted in whatever manner is least disruptive to the surrounding neighborhood.

The same subsection (E)(4)(d) already requires equipment cabinets, including their generator components, to be screened from view by a wall or landscaping approved by the city, with any wall architecturally compatible with the surrounding area. A telecommunication facility that runs its generator outside the permitted windows or exceeds the noise ceiling is out of step with the standards its permit was issued under, and (E)(6)(a) ties noise compliance to the same review that can lead to permit modification or termination for radio-frequency violations. The Community Development Department reviews telecom facility applications and can require a third-party technical study at the applicant's expense if compliance is disputed.