Control of Air Pollution from New Motor Vehicles: Heavy-Duty Engine and Vehicle Standards (Final Rule)

Under Title II of the Clean Air Act (42 U.S.C. 7521 et seq.; CAA), EPA is charged with issuing certificates of conformity for engine and vehicle prototypes that comply with applicable emission standards. Such certificates must be issued before engines produced according to certified prototypes may be legally introduced into U.S. commerce. A 2016 petition from over 20 organizations, including state and local air agencies from across the country, requested that EPA revise oxides of nitrogen (NOx) standards for HD engines. The petition cited concerns over adverse health and welfare impacts and the need to help certain areas attain the National Ambient Air Quality Standards (NAAQS) for ozone. In 2020, EPA published an Advance Notice of Proposed Rulemaking (ANPR) requesting comments on plans to revise the NOx emission standards for HD engines. In August 2021, Executive Order 14037 further directed the Agency to (1) set new NOX emission standards and (2) update the existing greenhouse gas (GHG) emissions standards for heavy-duty engines and vehicles. In March 2022, EPA published a Notice of Proposed Rulemaking (87 CFR 17414, March 28, 2022, the NPRM) requesting comments on changes to the NOx emission standards for HD engines. EPA is now adopting new HD criteria pollutant standards and changes to HD emissions certification and compliance provisions. While the Agency proposed targeted changes to the existing Phase 2 GHG standards for heavy-duty vehicles, those provisions are not being finalized at this time and therefore those provisions are not included in this information collection request. The Agency is also adopting revisions to several regulatory provisions related to other mobile source sectors including marine compression-ignition engines (Marine CI), small spark-ignition engines (Small SI), locomotives, light-duty vehicles, and various other types of nonroad engines, vehicles, and equipment. These changes consist of amendments to certain credit calculations, and regulatory changes to correct, streamline, and clarify existing provisions.

The latest form for Control of Air Pollution from New Motor Vehicles: Heavy-Duty Engine and Vehicle Standards (Final Rule) expires 2027-05-31 and can be found here.