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Colorado Clean Trucks


The Air Quality Control Commission (AQCC) adopted changes to Regulation Number 20, 5 CCR 1001-24, Colorado Clean Cars and Trucks Regulation which incorporated clean trucks regulations in April 2023. The regulations cover vehicles with a gross weight rating of 8,501 lbs. and greater. A heavy-duty vehicle in Regulation Number 20 is defined as any motor vehicle with a gross vehicle weight rating greater than 8,500 lbs, except passenger cars. Details regarding each of the heavy-duty vehicle regulations can be found through the links below, or in the full text of the most recent version of Regulation Number 20.


Heavy-Duty Low NOx (HD Low NOx)

Advanced Clean Trucks (ACT)

Large Entity Reporting (LER)

Historical Colorado Clean Truck Resources