The Advanced Clean Trucks rule saves lives, so why is Congress trying to axe it?

Diesel trucks and other diesel-fueled equipment are significant sources of particulate matter, including fine particulate matter (PM2.5) – a dangerous air pollutant that is small enough to penetrate deep into the lungs and bloodstream.  There is “no safe threshold under which exposure to ambient PM has no adverse health effects,” and both short- and long-term exposure to PM2.5 lead to a variety of harmful health effects.   

Short term spikes in PM2.5  are linked to increased mortality in infants, increased hospital admissions and emergency department visits for heart attacks, strokes, and chronic obstructive pulmonary disease, and increased severity of asthma attacks and hospitalization for asthma among children. The effects of long-term exposure to PM2.5 are even more severe, resulting in higher risk of premature death from heart disease, stroke, influenza, pneumonia, and lung cancer. More recent research also links long-term exposure to PM2.5 to death from chronic kidney disease, hypertension, and dementia. 

Despite the widespread harm to public health from diesel pollution, Congress and the Executive branch are taking steps to worsen pollution by attacking the Advanced Clean Trucks rule (ACT).   

CATF’s updated map shows the benefits of diesel pollution mitigation policy 

In April 2023, the U.S. Environmental Protection Agency granted California a waiver under the Clean Air Act to implement ACT, designed to reduce emissions of nitrogen oxides, PM2.5, other criteria pollutants, air toxics, and greenhouse gases. Ten other states have since adopted the rule under section 177 of the Clean Air Act, recognizing ACT as a powerful tool for improving air quality and protecting public health. 

To illustrate the potential for progress, Clean Air Task Force has updated its Deaths by Dirty Diesel map. Now, for the first time, the tool includes a section on ACT that highlights the lives that could be saved if states adopt and implement the rule. 

The ACT-focused maps present six possible futures, each representing different levels of state adoption and implementation of ACT rule. Users can explore public health benefits projected for 2032 and 2038 based on: 

• States that have already adopted ACT 

• A scenario where states that have adopted any California clean vehicle rule (“section 177 states”) adopt ACT 

• A scenario where all 48 contiguous states adopt ACT 

These scenarios offer a stark look at the stakes. If ACT is allowed to stand in states where it has already been implemented, it could save more than 1,000 lives and prevent approximately $12 billion in health-related damages over the next decade, especially in port regions and along major coastal freight corridors. Broadening adoption would deliver benefits across the heartland, more than doubling the number of lives saved. 

Despite benefits for human health, ACT and other tools to clean up the air are under attack 

In March 2025, EPA launched what it called the “biggest deregulatory action in U.S. history,” aiming to roll back 31 regulations, including regulations on emissions from light, medium, and heavy-duty vehicles. EPA has also frozen funding promised to schools to replace dirty diesel bus fleets with electric buses, and EPA’s attempt to freeze $20 billion in climate grants is impacting the sale of electric drayage trucks that could cut harmful pollutants from high-emitting ports.   

Meanwhile, Republicans in Congress are attempting a novel use of the Congressional Review Act to attack several California vehicle rules, including ACT and the Omnibus Low NOx Emissions rule.  This move would override states’ ability to set strong vehicle standards to protect their citizens from pollution. 

Diesel pollution continues to plague communities across the country.  As our maps show, ACT is a critical tool for combating this pollution.  Attacks on ACT and other regulatory tools for cleaning up the air demonstrate a blatant disregard for human health.  We urge Congress and the Administration to leave ACT and other important regulations in place.