Environmental Protection Agency (EPA) on Friday proposed tighter particulate matter/soot regulations, citing health concerns that the fine particles penetrate deep into the lungs and can result in serious health effects that include asthma attacks, heart attacks and premature death. EPA will accept public comment for 60 days once the proposal is published in the Federal Register.
Of particular air quality concern are residents of disadvantaged areas, which tend to be located along highways, near industrial parks and transportation hubs.
EPA just last month updated emission standards for heavy-duty commercial vehicles for the 2027 model year, tightening tailpipe NOx limits to a level 80%-plus below the current standard – a benchmark truck and engine OEMs nearly universally called "challenging."
Diesel-powered vehicles, vessels, locomotives and equipment account for more that 60% of all nitrogen oxides (NOx) and more than 70% of all fine particulate matter (PM2.5) emissions from U.S. transportation sources, according to the Union of Concerned Scientists. Diesel exhaust particulate matter includes soot and aerosols like ash particulates, metallic abrasion particles, sulfates and silicates.
EPA said in June 2021 it would reconsider the Trump administration’s December 2020 decision to retain the 2012 PM2.5 standards, citing available scientific evidence and technical information indicated that the standards may not be adequate to protect public health and welfare.
“This proposal to deliver stronger health protections against particulate matter is grounded in the best available science, advancing the Biden-Harris Administration’s commitment to scientific integrity and a rigorous scientific process," said EPA Administrator Michael Regan.
The move by EPA would bolster the national ambient air quality standard (NAAQS) for PM2.5, to better protect communities, including those most overburdened by pollution. These particles may be emitted directly from a source, such as construction sites, unpaved roads, fields, smokestacks, or fires; other particles form in the atmosphere as a result of complex reactions of chemicals such as sulfur dioxide and nitrogen oxides, which are pollutants emitted from power plants, industrial facilities and vehicles.
