Area Designations Maps / State and National

This page last reviewed September 22, 2009

This web site provides area designation maps of California for all criteria pollutants that are designated for the State and National standards. These maps are updated annually for the State area designations, as required by the Health and Safety Code (H&SC) section 39608. The Board makes State area designations for ten criteria pollutants: ozone, suspended particulate matter (PM10), fine suspended particulate matter (PM2.5), carbon monoxide, nitrogen dioxide, sulfur dioxide, sulfates, lead, hydrogen sulfide, and visibility reducing particles.

In contrast to the State area designations, the U.S. Environmental Protection Agency (U.S. EPA) makes national area designations for five criteria pollutants: ozone (8-hour standards; the 1-hour standard was revoked effective June 15, 2005), PM10, carbon monoxide, nitrogen dioxide, and sulfur dioxide. Although maps for the national area designations are provided below (designations as of September 2006), please refer to the U.S. EPA website for the most current information on the national area designations.

2006 State Area Designations

These changes became effective on July 26, 2007. There have been no regulatory changes to the State Area Designations since that time. These maps are the most current available.

Ozone (2006 area designation map, 1-hour area classification map)
PM2.5 (2006 area designation map)
PM10 (2006 area designation map)
Carbon Monoxide (2006 area designation map)
Nitrogen Dioxide (2006 area designation map)
Sulfur Dioxide (2006 area designation map)
Sulfates (2006 area designation map)
Lead (2006 area designation map)
Hydrogen Sulfide (2006 area designation map)
Visibility Reducing Particles (2006 area designation map)

National Area Designations

The following maps were current as of February 2009. Please refer to the U.S. EPA website to see if any changes have been made since that time. The new PM2.5 National Area Designations will be posted as soon as they become finalized. The National 1-Hour Ozone Standard was revoked in June 2005.

Ozone 8-Hour Standard (area designation map)
PM10 (area designation map) (updated: 2/2009)
PM2.5 (area designation map)
Carbon Monoxide (area designation map) (updated: 2/2009)
Nitrogen Dioxide (area designation map)
Sulfur Dioxide (area designation map)

Other Related Information

Air Basin and County Map Boundaries
Definitions State and National Designation Categories

For comments on page, email: tnajita@arb.ca.gov

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