California's Vehicle Smog Law

California requires many vehicles to pass smog inspections.

California requires smog inspections of vehicles with diesel or gasoline engines and were manufactured in certain years. The inspections are intended to reduce the levels of many pollutants, such as nitrogen oxides and volatile organic compounds.

Vehicle Types

Any gasoline-powered vehicle with model years after 1974 and diesel-powered vehicles manufactured after 1998 with a gross vehicle weight rating (GVWR) of less than 14,000 pounds are subject to the smog inspection requirement. Hybrids, electric vehicles and motorcycles are all exempt from the smog inspection, as are gasoline-powered vehicles with a GVWR of more than 14,000 pounds.

Counties

Thirty-four counties in California require vehicles pass a smog inspection to renew a vehicle registration. Another six counties require smog certifications within certain zip codes.

Considerations

According to the "Los Angeles Times," as of February 2010, there were 23 million motorists in California covered by the smog inspection program. The program has helped remove 400 tons daily of pollutants from California's air.

Fraud

A state audit in 2010 found that many vehicle inspection stations were improperly giving older-model vehicles passing smog inspection grades, and that there was widespread fraud in the inspection system.

References

• Los Angeles Times: 'Widespread fraud' in California's smog test program; Margot Roosevelt; February 2010.
• California Department of Motor Vehicles: Smog Information.
• Los Angeles Times: California cars 99% cleaner than in 1960s, but smog levels still high, study says; November 2010.