AB 1642: wildfire contamination standards explained

Is AB 1642 law?

Yes. AB 1642 was signed and chaptered on September 15, 2026 as Chapter 239. It adds a Wildfire Contamination chapter to California’s Health and Safety Code. This guide covers the final 2025–2026 session law.

Under California’s ordinary effective-date rule for regular-session laws, AB 1642 is scheduled to take effect January 1, 2027. That date follows from the state’s general rule; the agency deadlines below are later implementation milestones.

Enactment does not mean the new agency regulations have already been issued. The law sets separate deadlines through 2029 and provides interim lead and asbestos standards. Its operation is contingent on AB 1795 being enacted and taking effect by January 1, 2027; the Governor signed both bills on September 15.

What standards does it establish?

AB 1642 directs the Department of Toxic Substances Control (DTSC), in consultation with the Office of Environmental Health Hazard Assessment and other agencies, to develop rules for lead and asbestos testing, remediation, and restoration after a wildfire.

Once operative, and while the specified regulations and guidance are being developed, the law uses existing standards to determine residential occupancy clearance for wildfire-caused lead and asbestos contamination in a wildfire impact zone. That interim provision is limited to those two contaminants.

• Lead dust: interior concentrations must meet the federal lead-dust action levels referenced in the law, or a stricter applicable standard.
• Asbestos: properties must be evaluated, remediated, and restored in compliance with applicable California asbestos and federal emission standards, or stricter applicable standards.
• Future regulations: DTSC must address sampling, interpreting results, reducing exposure, cleanup, and lead-dust occupancy clearance, to the extent it determines sufficient scientific evidence exists.

When are the new rules and guidance due?

The law separates enforceable lead and asbestos regulations from guidance on indoor air, other contaminants, and schools. These are agency deadlines, rather than dates by which every homeowner must complete work.

Which homes and contaminants are covered?

The interim residential clearance provision applies within a “wildfire impact zone.” AB 1795 defines this as a ZIP Code wholly or partly within the fire perimeter. A house can fall within that zone even if the structure itself did not burn.

The future DTSC work covers residential properties and other locations as appropriate. Guidance due in 2029 addresses CAM 17 heavy metals, cyanide, lithium, manganese, dioxins and furans, and polycyclic aromatic hydrocarbons, subject to supporting science. Indoor air and school guidance have their own requirements.

How does AB 1795 connect to AB 1642?

AB 1642 supplies the contamination standards framework. Its companion, AB 1795, connects that framework to covered residential smoke damage claims within the wildfire impact zone.

AB 1795 addresses necessary sampling and testing costs, restoration to the property’s preloss condition, and occupancy clearance. It also restricts termination of additional living expense coverage before restoration and clearance, subject to the applicable policy limit. Sampling and testing coverage remains subject to the policy’s terms and provisions.

The companion law preserves existing insurer obligations. Its new §2060.2 expressly applies to claims occurring on or after that section’s operative date; the package should not be presented as automatically reopening every earlier wildfire claim.

What should homeowners keep in their records?

For a clearer conversation with an environmental professional, restoration contractor, or insurer, keep the evidence from each stage together. This is WyldSafe’s practical documentation recommendation:

• Dated photos and a record of affected rooms, belongings, and reported smoke damage.
• Sampling plans, laboratory results, and the standards used to interpret them.
• Written cleanup scopes, estimates, invoices, and contractor credentials.
• Postremediation results, clearance records, and written insurer decisions.