Groups urge EPA not to weaken air pollution protections for heavy-duty trucks, buses

Groups urge EPA not to weaken air pollution protections for heavy-duty trucks, buses

WASHINGTON, AUGUST 31, 2026 – Environmental and health groups are urging the Trump EPA not to weaken life-saving air pollution standards for heavy-duty vehicles like transit and school buses, delivery trucks, garbage trucks, and long-haul semi-trucks.

Environmental Defense Fund, NRDC (Natural Resources Defense Council), Sierra Club, Union of Concerned Scientists, Center for Biological Diversity, Environmental Law & Policy Center, Conservation Law Foundation, and Earthjustice filed comments with the EPA late Friday. 

In 2023, EPA finalized more protective standards for smog and soot-forming pollution from new heavy-duty vehicles with diesel engines. The standards will go into effect in 2027, and all leading manufacturers have announced they have engines ready to meet them.

The Trump EPA is now proposing to reverse key protections that are part of those updated standards. The protections ensure that heavy-duty vehicles continue to meet pollution limits throughout the time they are in use on our roads and highways, including through commonsense pollution and safety features called diesel exhaust fluid (DEF) inducements. If only 10% of heavy-duty vehicles do not use DEF it could increase pollution by enough to cause tens of thousands of early deaths and millions of extra asthma attacks, which would deliver a severe economic toll. The proposal would also create non-conformance penalties, allowing manufactures to pay to pollute, and would shorten the emissions warranty period and the “useful life” of the vehicle -- or the time period over which it must meet pollution standards.

The EPA’s own analysis, which ignores the impacts of removing DEF inducements, still shows that the proposed rollback would produce more harmful air pollution, putting the health of millions of Americans at risk — especially those in communities near busy highways and freight routes. Yet the EPA did not measure those health impacts.

New analysis in the groups’ comments shows that if EPA had monetized only the incomplete set of emissions increases that it does acknowledge, those disbenefits alone would still exceed EPA's asserted cost savings by a factor of ten. The EPA ascribes to the proposal a net cost savings of $12 billion; monetizing EPA’s own emission estimates shows that they constitute $98-126 billion in societal costs. 

Heavy-duty vehicles are a small fraction of the vehicles on our roads but are the largest transportation source of some pollutants that cause asthma attacks, bronchitis, heart attacks, strokes and preventable deaths.

QUOTES

“The Trump EPA’s proposal to weaken these protections against pollution from large trucks and buses is an unacceptable retreat from the agency’s core mission to protect public health. People across the country would face higher costs and more serious health risks because of this proposal.” – Alice Henderson, Director and Lead Counsel for Transportation and Clean Air at Environmental Defense Fund

 "Communities across the nation are breathing unsafe levels of soot and smog and trucks are a major contributor to that problem. Technology to reduce those harmful emissions is readily available and affordable, but the EPA’s proposal distorts the facts to let truck manufacturers dodge the bill for their own pollution controls – leaving the rest of us to pay the price with our health." – Guillermo Ortiz, senior vehicles advocate at NRDC.

 “Chicago is at the crossroads of numerous interstate highways, and the largest concentration of intermodal facilities. The Trump EPAs’ proposal to weaken controls of heavy-duty truck emissions threatens clear air for Chicagoans and communities across the Midwest and will have harmful effects on public health.” – Susan Mudd, Senior Policy Advocate at the Environmental Law & Policy Center

 “The Trump EPA is choosing polluters over people by weakening life-saving protections for heavy-duty trucks. Communities living near highways, freight routes, and warehouses breathe in higher levels of dangerous truck pollution and face the health consequences that come with it. They deserve cleaner air and stronger protections, not an EPA that bends to the demands of polluters and gives truck manufacturers a pass to put more pollution into our communities.” – Katherine Garcia, Director of Sierra Club’s Clean Transportation for All campaign

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