Recent reports about California withdrawing certain Clean Air Act waiver requests have caused some confusion, particularly around the Advanced Clean Fleets (ACF) Regulation. Contrary to some claims, California is not ending the ACF. State and local government fleets must continue to comply with ACF requirements.

California withdrew waivers for three regulations:

• Advanced Clean Fleets rules for high-priority private and federal fleets
• In-Use Locomotive Standards
• Commercial Harbor Craft regulations

These withdrawals do not impact other existing regulations like Clean Cars II, Clean Trucks, and the Heavy Duty Omnibus rules, which remain in effect.

The California Air Resources Board (CARB) has paused enforcement of ACF rules for drayage and high-priority fleets pending a federal waiver decision but may explore enforcement under state authority. Fleets in these categories should monitor CARB updates closely. NAFA will work with CARB and state leadership to refine ACF implementation and advises fleets to remain compliant with all applicable regulations.