Knowledge Center for the In-Use Off-Road Diesel-Fueled Fleets Regulation

This page last reviewed May 17, 2019

In December 2011, major amendments to the Off-Road Diesel Vehicle Regulation, which include delaying the first compliance date to no earlier than January 1, 2014, became effective. The changes to the regulation are reflected in the fact sheets, advisories, answers to frequently asked questions below, DOORS user guides, and forms.

Fact Sheets

Requirements in Effect Now - Enforcement and Regulatory Advisories

Frequently Asked Questions (FAQs)



Requirements and Compliance Questions

Diesel Emission Control Systems (DECS)/Retrofit Devices

On-road Engines and Off-road Vehicles

Water-Well Drilling Rig Guidance
  • Water-Well Drilling: Description of requirements for both in-state and out-of-state two-engine water-well drilling rigs, including the exemptions for those operating exclusively within the Counties of Fresno, Tulare, for emergency purposes, such as a drought State of Emergency.

Incentive Programs

  • Incentive Funding: Explanation of how compliance credits are awarded for vehicles/engines/retrofits funded through incentive programs (Moyer, Showcase, SEP and other funds).


forms The forms below are to be used to either request updates to information in a fleet's DOORS account that is not available for the fleet owner to update directly, or to submit information to ARB to complete annual reporting requirements.

Annual Reporting Forms


  • Small Fleet BACT Annual Exemption:  Small fleets requesting the BACT exemption in section 2449.1(b)(3)(C) of the In-Use Off-Road Diesel-Fueled Fleets Regulation must submit annually by March 1st.
  • Specialty Vehicle: Use this form to apply for a specialty vehicle designation.

Request for a Change in DOORS Information

(All documents are provided in Adobe Acrobat (PDF) unless otherwise indicated.)