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

This page last reviewed November 15, 2016

On Road Vehicles


The regulation requires diesel trucks and buses that operate in California to be upgraded to reduce emissions. Newer heavier trucks and buses must meet PM filter requirements beginning January 1, 2012.  Lighter and older heavier 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.
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 provides a variety of flexibility options tailored to fleets operating low use vehicles, fleets operating in selected vocations like agricultural and construction, and small fleets of three or fewer trucks.  

For other information about this regulation, other diesel engine regulations, or training programs, please contact an ARB diesel representative at 866-6DIESEL (866-634-3735) or visit the Truck Stop website.  This regulation does not apply to drayage trucks that transport marine containers.

Please sign up to receive email updates at the Truck and Bus Regulation Listserve.

What's New: 

Fleet Calculator Update (October 24, 2016)
  • An updated version of the Fleet Calculator has been posted. The Fleet Calculator is an Excel spreadsheet to assist fleet owners in evaluating various compliance strategies to comply with the Truck and Bus regulation. This update, in addition to function enhancements, introduces a feature that allows vehicle owner to import fleet information downloaded from the Truck Regulation Upload, Compliance and Reporting System (TRUCRS).
The Truck and Bus Reporting System Now Available for 2016 (December 10, 2015)
  • The Truck and Bus regulation reporting system is now available for fleet owners to report diesel vehicle information for 2016 at no cost. From this site, you can report your company and vehicle information. We encourage fleets to report early, before the January 31, 2016 reporting deadline. If you have previously reported, you can access to your account by using your user name and password.
Lighter Vehicle Compliance Options (September 21, 2015)
Diesel Particulate Filter Evaluation (May 11, 2015)
  • In October 2013, the Board directed staff to investigate stakeholder concerns regarding the cost, reliability, and fire safety of diesel particulate filters in on-road applications. Staff provided an update to the Board in April 2014, and the attached report discusses findings from the completed evaluation.

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