A new clarification in CARB’s Final Statement of Reasons (FSOR) may provide much-needed certainty regarding how the Advanced Clean Fleets (ACF) regulation applies to private contractors serving public agencies. Following extensive engagement by CRTA, its member companies, and low NOx truck coalition partners, stakeholders are cautiously optimistic that the interpretation significantly narrows the scope of affected fleets.

Language included in the FSOR suggests that private contractors would only be subject to the State and Local Government (SLG) fleet provisions of ACF when their vehicles are specifically dispatched by a public entity. Under this interpretation, only vehicles operating under the direct operational control of a state or local government agency would be covered by the regulation.

Additionally, CARB staff have indicated that this interpretation means the regulation would not extend to all contracted services. For example, general service providers, such as delivery services or catering companies, would not automatically be covered. Further, only the vehicles used to perform a qualifying contracted service would be considered, rather than an entire contractor’s fleet.

For many stakeholders, this represents a welcome shift from concerns raised earlier in the rulemaking process. The interpretation appears to align more closely with how the SLG provisions were originally understood before the recent amendment package was proposed.

That said, some uncertainty remains. The clarification appears in the FSOR and supporting documents rather than in the actual regulatory text. While CARB staff have indicated that future guidance documents and fact sheets will be updated to reflect this interpretation following approval by the Office of Administrative Law (OAL), many stakeholders believe greater regulatory certainty is necessary.

The proposed ACF amendments are currently under review by OAL after being submitted by CARB on July 29, 2026. OAL has until September 11 to act on the proposal. If approved, the amendments could take effect as early as October 1, 2026, depending on the filing date, or January 1, 2027, if filed later in the fall.

While questions remain, stakeholders are appreciative and cautiously optimistic that CARB’s latest clarification will narrow the scope of the private contractor provisions and provide much needed certainty for private companies doing business with public agencies. The regulation and materials submitted to OAL can be found here.