CARB Clean Truck Check

What is Clean Truck Check?

It is a regulation to test heavy-duty vehicles’ emissions control systems for proper operation. Clean Truck Check applies to nearly all diesel and alternative fuel heavy-duty vehicles with a gross vehicle weight rating (GVWR) over 14,000 pounds that operate on California public roads. This includes both in-state and out-of-state vehicles, as well as public vehicles (federal, state, and local government); motorcoaches; transit, shuttle and school buses; hybrid vehicles; commercial vehicles; personal vehicles; California registered motorhomes; single vehicle fleets; and vehicles registered outside of California (not including motorhomes).

Which vehicles are not subject to the regulation?

The heavy-duty vehicle types shown below are not subject to the regulation:

• • Zero-emission vehicles
  • Military tactical vehicles (title 13, CCR, section 1905)
  • Emergency vehicles (California Vehicle Code section 165 or California Health and Safety Code section 1797.84)
  • Historical vehicles (authorized by California Vehicle Code section 5004)
  • New vehicles with engines certified to the most stringent optional, NOx standard (less than or equal to 0.01 g/bhp-hr) –Only during the first four years of Clean Truck Check implementation (2023-2027)
  • Motorhomes registered outside of California
  • Vehicles operating under an experimental permit (authorized by California Health and Safety Code section 43014)