California Air Resources Board

The California Air Resources Board (CARB) may have recently sent you a postcard because DMV records show you may own a vehicle that is affected by CARB’s regulations. CARB is focused on cleaning up heavy-duty vehicle pollution to reduce smog-forming oxides of nitrogen (NOx) and toxic diesel particulate matter (PM) emissions and the resulting health risks. To meet California's health-based air quality standards and greenhouse gas emissions reduction goals, trucks and buses operated in the state must be as clean as possible. California is working to meet the Governor’s goal of 100% zero-emission transportation, where feasible, by 2035 for drayage vehicles and off-road transport refrigeration units (TRUs) and 2045 for all other heavy-duty vehicles. As a result of these efforts, the regulations listed below may affect your heavy-duty vehicle(s) or TRUs.

Clean Truck Check

The Clean Truck Check program (also known as the Heavy-Duty Inspection and Maintenance program)  applies to most diesel and alternative fueled heavy-duty vehicles with a gross vehicle weight rating (GVWR) over 14,000 pounds operating in California, including buses, motorhomes and agricultural vehicles. Clean Truck Check is similar to California’s Smog Check program for light-duty vehicles. The goal of Clean Truck Check is to ensure that heavy-duty vehicles operating in California remain equipped with properly functioning emissions control equipment and that these components are repaired in a timely manner when needed. Clean Truck Check requires reporting, payment of annual compliance fees, and emissions compliance testing. 

Learn more about Clean Truck Check.

In-Use Off-Road Diesel-Fueled Fleets Regulation (Off Road Regulation)  

The Off-Road Regulation applies to all self-propelled off-road diesel-fueled or alternative fueled     vehicles, with off-road compression-ignition engines that are 25 horsepower or greater and are owned or operated in California and most two-engine vehicles. This regulation requires fleets to reduce their emissions by retiring older vehicles and replacing with newer, cleaner vehicles, repowering older engines, or installing verified diesel emission control strategies in older engines, and by restricting the addition of older vehicles to fleets. CARB recently approved amendments to the Off-Road Regulation.

Learn more about the Off-Road Regulation.

Learn more about regulations at The Off-Road Zone.

Advanced Clean Fleets Regulation (ACF)

The ACF regulation requires certain fleets to phase-in medium- and heavy-duty zero-emission vehicles (ZEV) into their California fleets through 2042; The regulations pertain to three fleet types: 
1) State and local government fleets, including city, county, special district, and State agency fleets
2) Trucks performing drayage operations at seaports and railyards 
3) High Priority Fleets including federal agencies and entities that have $50 million or more in gross annual revenue or entities that own, operate, or control 50 or more vehicles.

Important dates:

• State and local agencies: Beginning January 1, 2024, State and local government fleets, including city, county, special district, and state agency fleets, are required to add ZEVs to the fleet as a percentage of their purchases each year. Starting January 1, 2024, 50% of vehicle purchases must be zero-emission vehicles and 100% of purchases must be zero-emission starting January 1, 2027. Small government fleets (those with 10 or fewer vehicles) and those in designated counties must start their ZEV purchases beginning in 2027. Alternatively, State and local government fleet owners may elect to meet ZEV targets as a percentage of the total fleet starting with vehicle types that are most suitable for electrification.
• Drayage Trucks*: Prior to January 1, 2024, all trucks were required to report in the Truck Regulations Upload, Compliance, and Reporting System (TRUCRS) to conduct drayage activities in California. Legacy drayage trucks reported in TRUCRS can continue to operate through their minimum useful life. Beginning January 1, 2024, only zero-emission drayage trucks may be reported in the TRUCRS system. All drayage trucks entering seaports and intermodal railyards will be required to be zero-emission by 2035.
• High priority fleets*: Starting January 1, 2024 High Priority Fleets, including federal fleets, must comply with the Model Year Schedule OR may choose to use the ZEV Milestones Option to phase zero-emissions vehicles (ZEV) into their fleets Starting January 1, 2024, fleet owners may only add ZEVs to their California fleet and, starting January 1, 2025, must remove internal combustion engine vehicles that have exceeded their useful life as specified in the regulation. Alternatively, fleet owners may elect to meet ZEV targets as a percentage of the total fleet starting with vehicle types that are most suitable for electrification.

*Please note that CARB has issued an Enforcement Notice that it has decided to exercise its enforcement discretion, and will not take enforcement action as to the reporting requirements or registration prohibitions of the drayage or high priority fleet requirements until U.S. EPA grants California a preemption waiver applicable to those regulatory provisions, or determines a waiver is not necessary.

Learn more about the Enforcement Notice.

Learn more about ACF.

Learn about more CARB regulations by visiting:
The TruckStop
ZEV TruckStop

Contact

Medium- and Heavy-Duty Vehicle Hotline

Email: 8666DIESEL@arb.ca.gov
Phone: (866) 634-3735 / (866) 6DIESEL

In-Use Off-Road Vehicle Hotline

Email: doors@arb.ca.gov
Phone: (877) 593-6677