Contact Us


News Releases By Date


EPA Strengthens U.S. Air Quality Standards

Release Date: 09/21/2006
Contact Information: Jennifer Wood, (202) 564-4355 / John Millett, (202) 564-4355 / En español: Lina Younes, 202-564-4355 /

(Washington, D.C. - Sept. 21, 2006) Today the U.S. Environmental Protection Agency announced the strongest national air quality standards in the country's history. These National Ambient Air Quality Standards (NAAQS) address fine and coarse particle pollution, also known as particulate matter (PM).

"Regardless of the rhetoric, facts are facts – today EPA is delivering the most health protective national air standards in U.S. history to all 300-million Americans," said EPA Administrator Stephen L. Johnson. "As a 26-year EPA scientist, I have spent my career working to hand down a cleaner, healthier environment – and these stronger air quality standards do just that."

PM is a complex mixture of extremely small particles and liquid droplets in the air (i.e. dust, soot and particles too small to see). The standards address two categories of particle pollution: fine particles and inhalable coarse particles. Fine particles are 2.5 micrometers in diameter and smaller; inhalable coarse particles have diameters between 2.5 and 10 micrometers. Exposure to particle pollution is linked to a variety of significant health problems ranging from aggravated asthma to premature death in people with heart and lung disease.

The final action significantly strengthens EPA's previous daily fine particle standard – by nearly 50 percent – from 65 micrograms of particles per cubic meter to 35 micrograms of particles per cubic meter of air. This standard increases protection of the public from short-term exposure to fine particles. By revising the daily fine particle standard, it will yield additional estimated health benefits valued at between $9 billion to $75 billion a year. These standards will reduce premature deaths, heart attacks and hospital admissions for people with heart and lung disease. EPA is also retaining the current annual standard for long-term exposure to fine particles at 15 micrograms per cubic meter. Based on recently updated benefits estimates, meeting this standard will result in benefits ranging from $20 billion to $160 billion a year.

EPA is protecting all Americans from effects of short-term exposure to inhalable coarse particles by retaining the existing daily PM
10 standard of 150 micrograms per cubic meter. This standard protects against premature deaths and increased hospital admissions for individuals with heart and lung disease. EPA is revoking the annual coarse particle standard because the available evidence does not suggest an association between long-term exposure to coarse particles at current ambient levels and health effects.

These standards will require significant reductions in air pollution. The comprehensive clean air strategy established by the Bush Administration gives states the tools needed to meet – and achieve reductions beyond – the national clean air standards. Two of the five rules with the largest projected health benefits in EPA's history have been adopted under the Bush Administration – Clean Air Interstate Rule (CAIR) and Clean Air Nonroad Diesel Rule. CAIR requires the power sector to reduce fine particle-forming sulfur dioxide emissions in the eastern U.S. by more than 70 percent and nitrogen oxides emissions by more than 60 percent. These reductions will help a number of areas meet the particle pollution standards, and CAIR will prevent an estimated 17,000 premature deaths annually. The Clean Air Nonroad Diesel Rule will require significant reductions of direct emissions of fine particles and emissions that contribute to particle pollution formation nationwide.

EPA selected the levels for the final NAAQS after reviewing thousands of peer-reviewed scientific studies about the effects of particle pollution on public health and welfare. The agency's science and policy review documents were examined by external scientific advisors and the public. The agency also carefully considered public comments on the proposed standards. EPA held three public hearings and received more than 120,000 written comments.

States must meet the revised standards by 2015, with a possible extension to 2020, depending on local conditions and the availability of controls. Later this month, EPA will issue guidance on monitoring fine and coarse particle pollution.

For more information about the final standards announced today:

For general information about particulate matter: