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Particulate Matter (PM) Pollution

Fact Sheets and Additional information Regarding the 2012 Particulate Matter (PM) National Ambient Air Quality Standards (NAAQS)

On December 14, 2012, the EPA strengthened the annual health-based standard for fine particles to a level of 12.0 micrograms per cubic meter (μg/m3) and retained the other particulate matter (PM) standards.

This page contains a variety of fact sheets and other documents describing that action.

For more information, visit the 2012 PM NAAQS page.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.