EPA Finalizes Phase 3 Greenhouse Gas Emission Benchmarks for Heavy-Duty Vocational Trucks

WASHINGTON, DC — The Environmental Protection Agency (EPA) published the final regulatory text for Phase 3 National Greenhouse Gas Standards for Heavy-Duty Vehicles on Saturday, establishing binding carbon emission reductions for model years 2027 through 2032.

Regulatory Scope and Manufacturer Targets

The rule sets technology-neutral greenhouse gas targets across heavy-duty vocational vehicles—including regional freight day-cabs, refuse haulers, school buses, and concrete mixers. The standards project that zero-emission vehicles will comprise approximately 30% to 40% of new heavy-duty vocational truck sales and up to 25% of long-haul tractor sales by 2032.

The EPA estimates the regulation will prevent 1 billion metric tons of greenhouse gas emissions through 2055 while generating $13 billion in annualized net public health and societal benefits.

Fleet Modernization and Industry Reaction

Commercial trucking associations acknowledged the environmental imperative but reiterated concerns regarding the availability of megawatt-level commercial charging depots and hydrogen fueling infrastructure along interstate freight corridors.

Public health organizations hailed the standard as a major victory for communities located adjacent to major freight ports and highway corridors, which suffer disproportionately from diesel particulate pollution.

Compliance Deadlines

The phase-in begins with vehicle model year 2027, with manufacturers required to submit initial annual compliance certifications starting in late 2026.