On-Road Truck and Bus Rule

The regulation requires diesel trucks and buses that operate in California to be upgraded to reduce emissions. Heavier trucks must be retrofitted with PM filters beginning January 1, 2012, and older trucks must be replaced starting January 1, 2015. By January 1, 2023, nearly all trucks and buses will need to have 2010 model year engines or equivalent.

Truck and Bus Reporting

Compliance requirements are currently in effect for heavier vehicles with a GVWR greater than 26,000 lbs. with engine years 1996 or newer.  To assist vehicle owners with the transition to the upcoming January 1, 2014, particulate matter (PM) filter compliance deadline, the Air Resources Board (ARB or Board) is taking specific actions to provide additional time for owners to complete their good faith compliance efforts and to take advantage of additional flexibility for many lower use vehicles and vehicles that operate solely in certain areas of the State as explained in the regulatory advisory MSC 13-28.  Owners will have the opportunity to use the following options under certain conditions but must report by January 31, 2014.

Tractor Trailer Rule

The California Air Resources Board in December 2008 adopted a new regulation to reduce greenhouse gas emissions by improving the fuel efficiency of heavy-duty tractors that pull 53-foot or longer box-type trailers. Fuel efficiency is improved through improvements in tractor and trailer aerodynamics and the use of low rolling resistance tires

Tractor Trailer Reporting

The regulation applies to 53' or longer box-type trailers (dry van and refrigerated van) and tractors that pull them. Fleets with 20 or fewer box-type trailers may take advantage of a phase-in option by reporting trailer information by September 1, 2012. The deadline for fleets with 21 or more box-type trailers to register has already passed. Additionally, the regulation currently requires all 2011 model year tractors that pull 53' or longer box-type trailers and all 2011 model year 53' or longer box-type trailers to be SmartWay certified or be retrofitted to comply. Fleets that have 2011 model year equipment and qualify for the short haul or local haul exemptions must report information about their 2011 model year equipment now. Reporting of other tractors and trailers within the fleet is not required at this time.


On this page you will find summaries of cases settled in lieu of litigation through the Air Resources Board's (ARB's) mutual settlement program and those that were resolved in civil or criminal litigation. Related case documents may be available upon request subject to applicable exemptions from disclosure under California's Public Records Act. Senate Bill 1402 (Chapter 413, Statutes of 2010) was enacted as urgent legislation on September 28, 2010 and requires ARB to post settlement agreements containing SB 1402 compliance statements on this website.

Motor Carrier & Broker Liability

Any in-state or out-of-state motor carrier, California broker, or any California resident who operates or directs the operation of any vehicle subject to this regulation shall verify that each hired or dispatched vehicle is in compliance with the regulation and comply with the record keeping requirements of section 2025(s)(4). Any person who fails to comply with the general requirements of this regulation, may be subject to civil or criminal penalties Pages 54-55.


The ARB's Heavy-Duty Vehicle Inspection Program and Periodic Smoke Inspection Program were adopted into law in 1988 (Senate Bill 1997) and 1990 (Senate Bill 2330), respectively to control excessive smoke emissions and tampering from heavy-duty diesel trucks and buses. The regulations, title 13 CCR, sections 2180-2189 for HDVIP, and title 13 CCR, sections 2190-2194 for PSIP, governing these programs were last amended in 2007.

ECL Requirements

Each vehicle operating in California - including those in transit from Mexico, Canada, or any other state – must have a label, called an Emission Control Label, showing that the engine met the required federal emission standards applicable for the model year of the engine.


Applies to heavy-duty diesel engines with a gross vehicle weight rating (GVWR) greater than 10,000 lbs. that operate on California highways including operators of both in-state and out-of-state registered sleeper berth equipped trucks. Requires manual or automatic shutdown after five minutes of idling.2008 and newer model year engines must be equipped with a non-programmable engine shutdown system that automatically shuts down the engine after five minutes of idling. Immediate shutdown is required at or within 100 feet of a school or school activity site. Restart no more than 30 seconds before departing, regardless of fuel type.

U.S. EPA SmartWay Verified or Designated Equipment

The Tractor-Trailer Greenhouse Gas Regulation requires 53-foot or longer dry van or refrigerated van trailers and the tractors that pull them on California highways to use certain equipment that the U.S. Environmental Protection Agency SmartWay program has verified or designated to meet their efficiency standards. This page provides information about the technologies that may be used to meet the requirements of the regulation. You can learn more about the different types of SmartWay verified or designated equipment by clicking on the buttons below.