Brentwood, CA Building Safety: Carbon Monoxide Detectors (2026)

California's Carbon Monoxide Poisoning Prevention Act of 2010, codified at Health and Safety Code Sections 17926 through 17926.2, requires a carbon monoxide alarm in every existing dwelling unit intended for human occupancy that has a fossil fuel burning heater, appliance, fireplace, or an attached garage. CO alarms must be listed and approved by the State Fire Marshal and meet UL 2034. Placement requirements under the California Residential Code R315 and CBC 915 are: outside each separate sleeping area in the immediate vicinity of bedrooms, and on every level of the dwelling including basements and habitable attics. Alarms may be battery-powered, plug-in with battery backup, or hardwired with battery backup; new construction and permitted alterations generally require hardwired and interconnected alarms. Combination smoke/CO units that meet both standards are allowed and often preferred. The manufacturer's end-of-life date (typically 5 to 10 years) must be observed, and alarms should be replaced when expired or when the end-of-life signal sounds. Landlord responsibilities mirror the smoke alarm rules: install and test at start of tenancy, then maintain unless the tenant fails to notify of a defect (HSC 17926.1). At resale, sellers must disclose the presence and operability of CO alarms (Civil Code 1102.6 series). Brentwood Building Division verifies installation at final inspection for any permit that touches mechanical systems, attached garages, or fuel-burning appliances. Penalties for non-compliance include administrative citations, orders to correct, and civil liability in the event of CO exposure. Homes that are fully electric with no fossil fuel appliances and no attached garage are technically exempt, though a CO alarm is still recommended.