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Announcements
March 29, 2007
EPA finalizes Clean Air Fine Particle Implementation Rule defining requirements for state plans to meet the 1997 national air quality standards for fine particle pollution.
September 21, 2006
EPA strengthens National Ambient Air Quality Standards for Particle Pollution.
This Web site provides information about the Clean Air Fine Particle Rule, an EPA action designating areas whose air quality does not meet the health-based standards established in 1997 for fine particle pollution. Learn more in the box to the right.
A designation is the term EPA uses to describe the air quality in a given area for any of six common pollutants known as criteria pollutants. Those pollutants include fine particles, which are unhealthy to breathe and have been associated with premature mortality and other serious health effects. Fine particles are 2.5 micrometers in diameter and smaller and are also referred to as PM2.5.
Once nonattainment designations take effect, the state and local governments have three years to develop implementation plans designed to meet the standards by reducing air pollutant emissions contributing to fine particle concentrations.
EPA strengthened the air quality standards for particle pollution in 2006. The Agency expects designations based on 2007-2009 air quality data will take effect in 2010. Learn more
This Web site contains the following information:
State Designations: EPA issued official designations for the PM2.5 standard on December 17, 2004 and made modifications in April 2005. They are summarized here.
Tribal Designations: EPA issued official designations for the PM2.5 standard on December 17, 2004. The designations impacting federally-recognized tribal lands are summarized here.
Regulatory Actions: Links to regulatory documents and information explaining regulatory actions related to PM2.5 emissions.
State Recommendations: This section provides links to the state recommendation letters, maps showing the counties the states
recommended as nonattainment, and EPA response letters.
Tribal Recommendations: This section provides links
to the tribal recommendation letters, maps showing the areas the tribes recommended as nonattainment, and EPA response letters.
PM2.5 Conditions: Links
to the AirNOW Web site with real-time information on PM2.5 conditions and web cameras around the country.
Air Quality Forecast: Links to the Air NOW Web site with PM2.5 air
quality forecasts for dozens of cities around the country.
Basic Information: Background on PM2.5 attainment issues and EPA
actions to address PM2.5 emission concerns.
Fine Particles & Health: Information about the health effects of fine
particles.
Policy Guidance: Links to EPA's April 2003 guidance on the
designations process for the fine particle standards, and related fact sheet.
Technical Data: Links to air quality technical data used to determine an
area's designation status.
Frequent Questions: Answers to common questions regarding
fine particles and the designations process.
Related Links: Related sites offering further information and assistance.
Glossary: Explanations of the technical terms and acronyms used
throughout the site.
A similar set of Web Pages exists for EPA's designated 8-hour ozone nonattainment areas designated in April
2004. Visit the 8-hour ground-level ozone designations page to learn more about the ozone designations.