Marin County, CA Noise from Specific Sources: Generator Noise (2026)

Section 6.70.030(5) splits construction noise into two tiers. Subsection (5)(a) sets the general work-hours schedule (7 a.m.-6 p.m. weekdays, 9 a.m.-5 p.m. Saturday, no work Sundays or the eight listed holidays), but subsection (5)(b) singles out the loudest machinery for a narrower window: "loud noise-generating construction-related equipment (e.g., backhoes, generators, jackhammers) can be maintained, operated, or serviced at a construction site for permits administered by the community development agency from eight a.m. to five p.m. Monday through Friday only." That means a portable generator running a job site cannot lawfully operate on Saturday at all, even though general construction work is otherwise allowed that morning and afternoon, and it must stop an hour before the general workday's 6 p.m. cutoff on weekdays.

The same five exceptions that apply to the rest of subsection (5) cover generators too: emergency work with 48-hour written notice to the Community Development Director under Development Code § 22.130.030, public-agency projects, work approved in writing by the Director for sufficient cause, minor low-noise jobs, and conditions set by a discretionary permit's review authority. Enforcement runs through § 6.70.040, adopted with the rest of subsection (5) by Ordinance 3431 in 2005: a first violation is an infraction, punishable by fines or administrative or civil action, and refusing an officer's order to shut the equipment down elevates the offense to a misdemeanor with fines, jail time, or both, on top of any stop-work order the building and safety division chooses to issue.