California Air Resources Board

CARB is responsible for setting standards and adopting regulations to achieve the maximum degree of emissions reduction possible from vehicular and other mobile sources. Motor vehicle emissions are responsible for approximately 55 percent of air pollution emissions statewide.

The Motor Vehicle Fuels Enforcement program regulates the composition of motor vehicle fuels and ensures compliance with motor vehicle regulations, including: California reformulated gasoline (CaRFG) regulations, diesel fuel regulations, and cargo tank vapor recovery regulations.