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Online applications for medium- and heavy-duty vehicle retrofit certifications are now available

The online application system for certification in the Diesel Retrofit Compliance Program is now open. To prepare for this process, there are several steps vehicle owners must complete. DEQ’s Retrofit Compliance Program web page has step-by-step instructions, including information on required documents, and a link to the online application. Avoid any delays in renewing vehicle registrations by beginning the certification process now.

DEQ recommends checking with an Approved Retrofit Installer as soon as possible to ensure the availability and timely installation of the applicable technology. The agency maintains a list of On Road Manufacturer Authorized Installers to help vehicle owners determine which approved retrofit technology to consider.


The Diesel Retrofit Compliance Program rules were adopted in 2021 as directed by Oregon Legislature House Bill 2007 (2019) to help reduce pollution on the state’s roadways and protect the health of our most vulnerable populations. As a result, medium- and heavy-duty vehicles powered by a 1996 or older diesel engine and with an owner address in Clackamas, Multnomah and/or Washington Counties may not renew registrations for 2023 unless they are equipped with approved retrofit technology and certified by Oregon DEQ. Deadlines for registration renewal are as follows:

  • Oregon Driver and Motor Vehicle Services (DMV): Jan. 1, 2023
  • Commerce and Compliance Divisions (CCD): Jan. 31, 2023


Registration renewal timelines, engine year requirements and diesel vehicle exemption questions can be addressed by the Oregon Driver and Motor Vehicle Services or Oregon Commerce and Compliance Division based on the gross vehicle weight rating (See below). The “gross vehicle weight rating” is the value specified by the manufacturer as the maximum design loaded weight of a vehicle.

  • DMV: Medium-duty (14,001 - 26,000 lbs.) vehicles, call DMV Customer Assistance at 503-945-5000
  • CCD: Heavy-duty (>26,000 lbs.) vehicles, email at
  • DEQ cannot answer questions concerning exemptions; please contact the above.

The Retrofit Compliance Program online application and details on the submission process are available at If you have questions on the applications and/or submission process, please contact Rick Reznic, DEQ project manager, at