Truck and Bus Regulation
On-Road Heavy-Duty Diesel Vehicles (In-Use) Regulation

The regulation was initially considered in 2008 and requires fleets that operate in California to reduce diesel truck and bus emissions by retrofitting or replacing existing engines. Amendments were considered in December 2010 to provide more time for fleets to comply. The amended regulation would require installation of PM retrofits beginning January 1, 2012 and replacement of older trucks starting January 1, 2015. By January 1, 2023, nearly all vehicles would need to have 2010 model year engines or equivalent.

The regulation applies to nearly all privately and federally owned diesel fueled trucks and buses and to privately and publicly owned school buses with a gross vehicle weight rating (GVWR) greater than 14,000 pounds. The regulation has provisions to provide extra credit for PM filters installed prior to July 2011, has delayed requirements for fleets with 3 or fewer vehicles, provisions for agricultural vehicles and other situations. The regulation does not apply to trucks transporting marine containers that comply with the Drayage Truck Regulation. For further information, please contact an ARB diesel representative at 866-6DIESEL (866-634-3735).
 

original document: http://www.arb.ca.gov/msprog/onrdiesel/onrdiesel.htm