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News Releases from HeadquartersAir and Radiation (OAR)

EPA Proposes to Retain NAAQS for Particulate Matter

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EPA Press Office (

WASHINGTON (April 14, 2020) — Today, the U.S. Environmental Protection Agency (EPA) is announcing its proposal to retain, without changes, the National Ambient Air Quality Standards (NAAQS) for particulate matter (PM) including both fine particles (PM2.5) and coarse particles (PM10). This proposal comes after careful review and consideration of the most current available scientific evidence and risk and exposure information, and with consultation and confirmation by the agency’s independent science advisors.

“The U.S. has made incredible strides in reducing particulate matter concentrations across the nation,” said EPA Administrator Andrew Wheeler. “Based on review of the scientific literature and recommendation from our independent science advisors, we are proposing to retain existing PM standards which will ensure the continued protection of both public health and the environment.”

As a result of Clean Air Act programs and efforts by state, local and tribal governments, as well as technological improvements, average PM2.5 concentrations in the U.S. fell by 39 percent between 2000 and 2018 while average PM10 concentrations fell by 31 percent during the same period.

With this action, EPA is following the principles established in the earliest days of this administration to streamline the NAAQS review process and to fulfill the statutory responsibility to complete the NAAQS review within a 5-year timeframe. More information about the rule can be found at:

Public Officials Voice Support for EPA's Action:

Congressman Rob Bishop (UT-01), House Natural Resources Committee Ranking Member: “The United States is a world leader in growing our economy while simultaneously improving air quality. Between 1970 to 2018, air pollutants identified in the Clean Air Act have fallen 74 percent while the US economy has grown by 275 percent. EPA’s decision to maintain the current National Particulate Matter Standards reflects this fact. Administrator Wheeler and the Administration should be commended for partnering with states, local, and tribal governments in improving our air quality while allowing economic growth to continue.”

Congressman Paul Gosar (AZ-04), Ranking Member of the Energy and Mineral Resources Subcommittee, House Natural Resources Committee: “Communities across the West are working hard every day to meet current environmental standards. Today’s announcement is proof the EPA has listened to the concerns of local communities who are weary of excessive government overreach. I applaud President Trump and Administrator Wheeler for working in concert with state, local, and tribal governments to ensure we have clean air and clean water.”

Congressman James Comer (KY-01), Ranking Member of the Environment Subcommittee, House Oversight and Reform Committee: “I strongly support EPA’s decision to maintain the current Particulate Matter (PM) standards. The current PM standards are among the strictest safeguards in the world. EPA will continue to protect the environment while not placing unnecessary burdens on local communities. Under Administrator Wheeler’s leadership, EPA has proven that it is possible to improve air quality in the United States while simultaneously growing the economy.”

Congressman Devin Nunes (CA-22): “I am gratified that the EPA’s standards are now guided by the scientific evidence and the needs of local communities. Farming families can rest assured the federal government will not impede their livelihoods or their continued ability to feed the nation.”

Congressman Andy Biggs (AZ-05): “Air quality in the United States continues to improve under President Trump’s administration. The EPA’s proposed action relieves our state from an increase in regulatory burdens by maintaining the current national particulate matter standards. This gives Arizona the flexibility to work on its current plan to meet and exceed the EPA’s standards and improve our state’s environmental health.”

Congressman Larry Bucshon (IN-08): “In these uncertain times, removing barriers to innovation and championing free-market solutions driven by the American consumer will provide Hoosier manufacturers and energy producers with the certainty they need. I applaud the Administration’s decision to maintain the existing National Particulate Matter Standards, which ensures Hoosier families have access to cleaner air and that burdensome regulations do not stifle Main Street jobs. We must continue to provide the certainty needed to promote innovation and economic growth,” said Dr. Bucshon

Congresswoman Carol Miller (WV-03): “With this decision, Administrator Wheeler has proven, once again, that we can protect our environment and prioritize the health of our citizens without unnecessary and overburdensome regulations. I applaud the EPA for their commitment to improving our air quality, which is now five times cleaner than the global average.”  

Congressman Morgan Griffith (VA-09): “In maintaining the national Particulate Matter standards set in 2012, the EPA has made the right call. Our air quality has improved under the current standards, and we can continue to make progress without imposing costly new burdens on the energy and manufacturing sectors.”

Congressman Alex Mooney (WV-02): “I am pleased to hear the EPA is maintaining the current national PM standards. After eight years of former President Obama’s War on Coal, President Donald Trump’s leadership is saving jobs in our coal industry. This decision will improve air quality while protecting West Virginia energy jobs.”

Congressman Bill Flores (TX-17): “I am pleased to see the Trump administration and the EPA employ a science and data driven approach to address the NAAQS for particulate matter. Communities throughout the nation, including some in the 17th Congressional District of Texas, have been struggling to prepare for previously proposed rules which had increasingly unreasonable standards. The EPA’s decision to retain current standards, without changes, rightly reflects the long-term trend data of dramatically decreased particulate matter as well as the needs of our state and local governments. Now, more than ever, our communities, small businesses, and industries need thoughtful, scientific-based certainty to dig our economy out of current coronavirus-related economic harm while continuing the trend of greatly improved air quality for hardworking American families.”

Austin Caperton, Cabinet Secretary, West Virginia Department of Environmental Protection: “With several announcements over the past few weeks the Trump administration, and the EPA administration, continue to demonstrate that states have rights and, more importantly, that science will be the guiding light when it comes to regulating the environment. The announcement that the PM2.5 and PM10 standards will remain as is until science dictates otherwise is but yet another example. And I'm proud to report that West Virginia is in full compliance with both standards.”

Kenneth Wagner, Oklahoma Secretary of Energy and Environment: “The regulatory decision to keep Particulate Matter standards steady under the NAAQS is strongly supported by the State of Oklahoma. The certainty of holding these standards steady allows businesses in Oklahoma to plan, comply and hopefully, grow after this incredibly difficult economic period.”

Libby Szabo, Commissioner, Jefferson County, CO: “Maintaining the National Ambient Air Quality Standards (NAAQS) for particulate matter is a win, win. It not only makes sure we are setting a high standard for air quality but it also provides the requisite protection for public health and welfare of our communities, while making sure we are consistent with the best available science. My hat goes off to the EPA for finding this delicate balance.”


  • The Clean Air Act requires the EPA to set NAAQS for “criteria pollutants.” Currently, PM and five other major pollutants are listed as criteria pollutants. The law requires the EPA to periodically review the relevant scientific information and the standards and revise them, if appropriate, to ensure that the standards provide the requisite protection for public health and welfare.

  • In the prior review of the PM standards, which was completed in 2012, the EPA revised the level of the primary annual PM2.5 standard from 15.0 to 12.0 mg/m3.

To view a fact sheet, click here: