Medium and heavy-duty trucks are a major contributor to transportation-related emissions in the U.S. In 2022, they accounted for roughly 23% of the sector's total emissions, with only light-duty trucks having a larger share, and current estimates are the same. Since 1990, emissions from these vehicles have risen by roughly 75 percent.
Pollution from heavy-duty vehicles contributes to climate change and can exacerbate serious health issues such as respiratory and heart ailments, especially for the 72 million people in the United States who live close to truck freight routes and are more likely to be people of color or come from low-income households. The American Lung Association estimates that transitioning to zero-emission trucks and electricity could save nearly 67,000 lives by 2050.
2021: In August, 2021, the U.S. Environmental Protection Agency (EPA) announced the Clean Trucks Plan –representing the most protective set of EPA regulations ever for heavy-duty vehicles, with the goal of significantly reducing pollution, protecting public health, and responding to the urgency of climate change.
Medium- and heavy-duty truck emissions in the United States fell roughly one percent in 2022, to 413 million metric tons of carbon dioxide equivalent (MtCO₂e).
2022: On December 20, 2022, the Clean Trucks Plan adopted a “Final Rule and Related Materials for Control of Air Pollution from New Motor Vehicles: Heavy-Duty Engine and Vehicle Standards” which set stronger emission standards to further reduce air pollution, including pollutants that create ozone and particulate matter, from heavy-duty vehicles and engines starting in 2027.
2024: On March 29, 2024, the EPA announced a “Final Rule: Greenhouse Gas Emissions Standards for Heavy-Duty Vehicles-Phase 3” which set still stronger standards to reduce greenhouse gas emission from heavy duty vehicles beginning in model year 2027.
Those new federal rules were estimated to curtail a billion tons of greenhouse gas emissions each year and provide financial benefits worth $13 billion annually “related to public health, climate, and savings for truck owners and operators.” Big rigs, delivery trucks, cement mixers, garbage trucks, transit buses and school buses are all included.
2025: However, the Trump administration’s vow to eliminate electric car mandates has affected and reversed many truck vehicle emission standards too. If approved, the EPA’s proposal to rescind the endangerment finding would repeal all GHG emissions standards for vehicles. Additionally, the One Big Beautiful Bill eliminated tax incentives for cleaner vehicles.
2021-2022 A NY State Senate bill, sponsored by Pete Harckham, passed into law providing that 100% of in-state sales of new passenger cars and trucks shall be zero-emissions by 2035.
2023: In April 2023, California air regulators had already approved landmark zero-emission rules for trucks and locomotives. Those were expected to supersede the federal regulations for large truck fleets operating within the state, whether they are registered in California or not.
2025: Trump revoked California’s regulations, which multiple states had also adopted. Still, California is fighting back in court, and is beginning to put together new rules for heavy-duty truck emissions regulations starting in December 2025.
CREDIT: EPA
