Designations

A designation is the term EPA uses to describe the air quality in a given area for any of six common air pollutants known as criteria pollutants. Those pollutants include ground-level ozone and fine particles, which are unhealthy to breathe. Fine particles are those less than 2.5 micrometers in diameter and are also referred to as PM2.5.

In 2004 EPA announced final designations for the new more protective 8-hour ozone and fine particle standards. Areas designated as "nonattainment" must develop, submit to EPA, and enact plans for reducing the levels of pollutants that contribute to their ground-level ozone and/or particle pollution problems.

The map below shows the counties designated as nonattainment for both standards. Green counties are those that are unclassifiable or nonattainment for ozone. Blue outlined counties are those that are unclassifiable or nonattainment for PM.

To learn more about these actions, visit :

• 8-hour ground-level ozone designations page at www.epa.gov/ozonedesignations
• PM designations page at www.epa.gov/pmdesignations