The Department of Energy and Environmental Protection proposed to adopt California’s Advanced Clean Cars II, Low Emission Vehicle, Low NOx "Ominbus," and Advanced Clean Trucks regulations. Adoption of these regulations would establish more stringent emission requirements for medium- and heavy-duty internal combustion engines and implement requirements for vehicle manufacturers to progressively increase the sale of advanced technology vehicles, including battery electric and hydrogen vehicles, from 2027 through 2035. A hearing will be held August 22, 2023.

The Department of Environmental Protection adopted California's emission standards for heavy-duty vehicles by incorporating by reference California's Low NOx Omnibus rules. See:

The Department of Ecology adopted amendments to regulations implementing California's vehicle emission standards, including the early action zero emission vehicle credits, one-time fleet reporting requirement, Advanced Clean Cars II Standards, as well as heavy-duty engine and vehicle omnibus regulation and associated amendments. See https://lawfilesext.leg.wa.gov/law/wsr/2023/01/23-01-102.htm.

The Massachusetts Department of Environmental Protection proposed amendments to 310 Mass. Code Regs. 7.40. The proposed amendments would incorporate recent revisions made by the California Air Resources Board to the greenhouse gas emissions standards for passenger cars, light-duty trucks, and medium-duty passenger vehicles for model years 2021 through 2025. A hearing will be held January 28, 2019. Comments are due February 8, 2019. See http://www.sec.state.ma.us/spr/sprpub/011119a.pdf.

The Department of Environmental Conservation proposed amendments to Subchapter XI, Low Emission Vehicle Program. The proposed amendments would incorporate California's change to its vehicle emission standards, which clarifies that vehicle manufacturers may not substitute compliance with federal greenhouse gas (GHG) emissions standards in order to comply with California GHG emissions standards. A hearing will be held October 21, 2018. Comments are due October 29, 2018. See https://secure.vermont.gov/SOS/rules/.