Federal rules today
FMCSA has not adopted operating rules specific to electric or zero-emission CMVs. Battery-electric and other zero-emission trucks are subject to the same Federal Motor Carrier Safety Regulations as diesel trucks - driver qualification, inspection and maintenance, and hours of service. Charging stops are handled under the existing hours-of-service rules in 49 CFR Part 395.
No ZEV-specific FMCSA rule or proposed rule has been published in the Federal Register. Truck size and weight limits on the Interstate System are set by Congress in 23 USC 127 and administered by the Federal Highway Administration, not FMCSA.
Current state operating rules
California, Washington, Oregon, and several other states adopted Advanced Clean Trucks (ACT) rules, which set zero-emission sales requirements for truck manufacturers rather than for motor carriers. In June 2025 Congress disapproved EPA's Clean Air Act waiver for California's ACT rule (Public Law 119-15), so confirm the current status of any state ZEV rule with that state's air agency.
For now, ZEV CMVs operate under the same FMCSA rules as conventional CMVs. On weight, 23 USC §127(s) lets a vehicle powered primarily by natural gas or by electric battery power exceed the federal weight limit on the power unit by up to 2,000 lbs, up to a maximum gross vehicle weight of 82,000 lbs.
Looking ahead
Carriers with ZEV pilots in their fleet should watch the Federal Register (federalregister.gov) for any FMCSA or FHWA rulemaking that affects zero-emission CMVs.
No 2026 compliance change is required. Fleet operators considering ZEV procurement should plan around state-level mandates first, federal rules second.