Unincorporated Santa Clara County's Noise Ordinance includes a motor-vehicle noise provision (Section B11-155). On public roads, vehicle exhaust and muffler noise are primarily controlled by California Vehicle Code sections 27150 and 27151, which require an adequate muffler and prohibit modified exhaust exceeding 95 dBA.
The County Noise Ordinance (Division B11, Chapter VIII) contains a dedicated section on motor vehicle noise limits (Section B11-155). For vehicles operated on public streets and highways, however, the controlling law is generally state law, which preempts local exhaust standards for on-road vehicles. California Vehicle Code Section 27150 requires every motor vehicle to be equipped with an adequate muffler in constant operation and properly maintained to prevent excessive or unusual noise, and prohibits cutouts, bypasses or similar devices. Vehicle Code Section 27151 prohibits modifying a vehicle's exhaust system in a manner that amplifies or increases noise beyond legal limits, and provides that for vehicles under 6,000 pounds gross vehicle weight (other than motorcycles), a sound level of 95 dBA or less - when tested per the most current SAE International standard - complies with the section. Operating a vehicle with an illegally modified exhaust is a citable offense. Off-road and stationary vehicle noise on private property within the unincorporated County can additionally fall under the County's exterior noise limits and prohibited-acts provisions. Enforcement of on-road vehicle noise is typically by the Santa Clara County Sheriff or CHP, while the Department of Environmental Health handles property-line noise complaints.
Operating a vehicle without an adequate muffler, with a cutout/bypass, or with a modified exhaust exceeding 95 dBA (vehicles under 6,000 lbs) violates California Vehicle Code 27150-27151 and is citable. Excessive vehicle noise affecting property in the unincorporated County may also be addressed under the County Noise Ordinance.
Other ordinances people look up for this city. Green dot = verified primary-source excerpt.
Palo Alto, CA
Palo Alto requires encroachment permits for new driveways, regulates curb cut dimensions, and prohibits blocking sidewalks or adjacent driveways under traffi...
Palo Alto, CA
Palo Alto restricts RV, trailer, and boat storage on public streets and requires screening for large recreational vehicles on residential property under zoni...
Palo Alto, CA
Palo Alto prohibits barbed wire, razor wire, and electrified fencing in residential zones, and requires non-combustible materials within 5 feet of structures...
Palo Alto, CA
Palo Alto requires fences to be structurally sound, maintained in good condition, and compliant with Dark Sky lighting rules, height limits, and VHFHSZ wildf...
Palo Alto, CA
Palo Alto requires a building permit for fences over 7 feet tall or any retaining-wall combination exceeding 4 feet; fences at or under 6 feet generally do n...
Palo Alto, CA
Palo Alto requires a building permit for any retaining wall over 3 feet tall or supporting a surcharge, with engineered drawings required above 4 feet under ...
See how Palo Alto's vehicle noise rules stack up against other locations.
Help us keep this page accurate. If you notice an error or outdated information, let us know.