The U.S. Environmental Protection Agency (EPA) on March 7 proposed new, stronger standards to promote clean air and reduce pollution from heavy-duty vehicles and engines starting in model year (MY) 2027.

The proposed standards would reduce emissions of smog- and soot-forming nitrogen oxides (NOx) from heavy-duty gasoline and diesel engines, and set updated greenhouse gas (GHG) standards for certain commercial vehicle categories. EPA officials say this proposed rule would ensure the heavy-duty vehicles and engines that drive American commerce and connect people across the country are as clean as possible while charting a path to advance zero-emission vehicles in the heavy-duty fleet.

"Seventy-two million people are estimated to live near truck freight routes in America, and they are more likely to be people of color and those with lower incomes. These overburdened communities are directly exposed to pollution that causes respiratory and cardiovascular problems, among other serious and costly health effects," says EPA Administrator Michael S. Regan.

Consistent with President Biden's Executive Order, "Strengthening American Leadership in Clean Cars and Trucks," the proposed action would reduce NOx emissions from trucks by as much as 60% in 2045. It would result in widespread air quality improvements across the U.S., especially in areas already overburdened by air pollution and diesel emissions. The benefits of the proposed rule would exceed its costs by billions of dollars. EPA estimates that by 2045 the most ambitious option outlined in the proposal would have annual results of:

• Up to 2,100 fewer premature deaths
• 6,700 fewer hospital admissions and emergency department visits
• 18,000 fewer cases of asthma onset in children
• 3.1 million fewer cases of asthma symptoms and allergic rhinitis symptoms
• 78,000 fewer lost days of work
• 1.1 million fewer lost school days for children

The EPA says the March 7 action is the first step in EPA's "Clean Trucks Plan," a series of clean air and climate regulations that the agency will develop over the next 3 years to reduce pollution from trucks and buses and to advance the transition to a zero-emissions transportation future.

The proposed revisions to existing GHG standards for MY2027 and beyond would set updated GHG emissions standards for subsectors where electrification is advancing at a more rapid pace. These sectors include school buses, transit buses, commercial delivery trucks and short-haul tractors. In a separate action, EPA will be setting new GHG emissions standards for heavy-duty vehicles as soon as model year 2030. This action will more comprehensively address the long-term trend towards zero emissions vehicles across the heavy-duty sector.

The March 7 proposal reflects input from stakeholders including community groups, manufacturers, and state, local, and tribal governments. A public comment period and hearing will give stakeholders and the public an opportunity to comment on the proposal. Click here for more information on the rule on the public comment process.