Maryland and Massachusetts Postpone Zero- Emission Mandate for Trucks
Massachusetts and Maryland — two of the 10 states that passed California’s Advanced Clean Truck Rule — have delayed enforcement of the stringent emissions targets.
The rule requires manufacturers of on-road medium- and heavy-duty vehicles to produce and sell an increasing percentage of zero-emission vehicles from model years 2025 through 2035.
The Massachusetts Department of Environmental Protection on Tuesday announced a two-year reprieve for truck manufacturers unable to meet the requirements of the Advanced Clean Trucks program. Manufacturers will get a grace period for the 2025 and 2026 model years if they continue to make internal combustion
engine trucks for distributors.
And Maryland Gov. Wes Moore earlier this month signed an executive order suspending enforcement of the ACT program for two years.
MassDEP said that truck manufacturers find the regulation too difficult. Some manufacturers are limiting ICE truck sales to ensure they comply with the sales requirements.
The department also said the Trump administration created “significant uncertainty around ZEV incentives, charging investments, manufacturing and tariffs, each of which threaten a smooth transition to medium- and heavy-duty ZEVs.”
The delay gives manufacturers “flexibility” while keeping the state “on track” to achieve emissions reductions, MassDEP said.
The rules in Massachusetts, New Jersey, New York, Oregon and Washington arescheduled to go into effect with MY 2025 vehicles. Vermont’s rules will take effect in the 2026 model year and rules in Colorado, Maryland, New Mexico and Rhode Island are set to begin in the 2027 model year.
“Legislation has been introduced in all of the 2025 states to delay implementation of the rule until at least 2027,” the RV Industry Association said this month in a legislative update.
A bill was also introduced in the Vermont legislation last week and a proposal in Washington would repeal the ACT Rule in the state.
“While federal law permits states to adopt California’s motor vehicle emission standards as an alternative to the federal [Clean Air Act] standards, this remains optional,” according to the Washington bill (SB 5091). “Decarbonizing the transportation sector is achievable and an important objective in Washington state but adopting California’s standards limits flexibility in meeting Washington’s unique needs and economy.”
Reporting by Donna Harris, dharris@opisnet.com
Editing by Jeff Barber, jbarber@opisnet.com
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