On-Road Mobile Source Programs

This page last reviewed March 26, 2015


The California Clean Air Act (CCAA) mandates the Air Resources Board (ARB) to achieve the maximum degree of emission reductions from all on- and off-road mobile sources in order to attain the state ambient air quality standards. On-road mobile sources include:


Image of a Dynamometer Certification Program The On-Road Certification/Audit Section is responsible for the certification and production audit of new passenger cars (PC), light-duty trucks (LDT), medium-duty vehicles (MDV), heavy-duty engines (HDE) and vehicles (HDV) including urban buses (UB), on- and off-road motorcycles (ONMC and OFMC), all-terrain vehicles (ATV), and electric golf carts (eGC).
Image of Environmental Performance Label
Environmental Performance Label The label is intended to help consumers compare the smog forming emissions from different vehciles within that model year.
Image of Truck Heavy-Duty Truck and Bus Surveillance Program (TBSP) This program tests in-use heavy-duty vehicles with low and high mileage to better understand the emissions inventory of these vehicles operating throughout the State. Testing is conducted at ARB's heavy-duty testing facility located at Depot Park in Sacramento, California.
Image of Traffic Low Emission Vehicle Program The Low Emission Vehicle Program area of the website includes all recent information on the Low Emission Vehicle Program, including the LEV II amendments.
Image of Diagnostic System On-Board Diagnostics (OBD) Program On-Board Diagnostic (OBD) systems are incorporated into the computers on-board new vehicles to monitor components and systems that affect emissions when malfunctioning.
Image of Truck On-Road Heavy-Duty Vehicle Program Emissions from on-road heavy-duty vehicles are major contributors to poor air quality in California, in amounts highly disproportionate to the numbers of these vehicles.
Image of On-Road Motorcycle On-Road Motorcycle Regulation Along with other motor vehicles, the ARB has identified on-road motorcycles as a potential source of air pollution which can be reduced cost effectively.
On Road Vehicles On-Road Trucks (In-Use) Control Measure All diesel fueled trucks, buses, trailers and transportation refrigeration units operating in California, including those based out of state, have requirements to reduce air pollution and improve the state's overall air quality.
Truck image On-Road Medium- and Heavy-Duty Greenhouse Gas (GHG) Regulations

Phase 1 GHG establishes new regulation for GHG emissions from heavy-duty trucks and engines sold in California.
CA Phase 2 GHG regulations are being developed to achieve further fuel economy improvements and GHG reductions beyond Phase 1.

Image of Specialty Constructed vehicles Specially Constructed Vehicles Certification Process The ARB is developing regulation modifications to enable certification of new engine packages intended for use in specially constructed vehicles (i.e., kit cars).
Image of Electric Vehicle Zero-Emission Vehicle Program ARB is committed to the successful introduction of Zero Emission Vehicles such as battery and fuel cell electric vehicles and is taking steps to ensure the market is ready.
Image of School Bus Alternative Fuel Conversion Certification Procedures. The ARB is developing regulation modifications to the alternative fuel conversion certification procedures for new and in-use vehicles and engines (i.e., alt fuel conversions).