Jump to main content or area navigation.

Contact EPA Pacific Southwest Air Program

Pacific Southwest, Region 9

Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations

Air Actions, Arizona

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Phoenix Carbon Monoxide Actions

January 2005: Final Redesignation for Carbon Monoxide

On January 5, 2005, EPA finalized the rule to redesignate the Phoenix metropolitan area in Arizona to attainment for the National Ambient Air Quality Standard (NAAQS) for carbon monoxide (CO), as well as to approve the attainment demonstration and maintenance plan showing maintenance of the CO standard through 2015. EPA also finalized a boundary change which removes the Gila River Indian Community (GRIC) from the Phoenix CO maintenance area.

The Phoenix metropolitan area was originally designated as a moderate CO nonattainment area under the Clean Air Act Amendments of 1990, with an attainment date of December 31, 1995. As a result of the area's failure to reach attainment by the end of 1995, EPA reclassified the area as a serious nonattainment area in 1996, with a new attainment date of December 31, 2000. The Phoenix metropolitan area has not had an exceedance of the CO standard since 1996. The area has been reporting clean data for CO for more than seven years. Cars and other gasoline-powered motor vehicles cause more than 75 percent of the Valley's CO.

The State and local community have worked hard to improve Phoenix's air quality. The area has a number of innovative programs including the country's leading vehicle emissions inspection program, a cleaner burning gasoline program, and woodburning restrictions. The proposed revisions to the State Implementation Plan (SIP) will mean continued clean air for the Phoenix area.

Contact Information

Wienke Tax (tax.wienke@epa.gov)
Office of Air Planning
EPA Region 9
(415) 947-4192


September 2004: Proposed Redesignation for Carbon Monoxide

The above actions were proposed on September 21, 2004

Contact Information

Wienke Tax (tax.wienke@epa.gov)
Office of Air Planning
EPA Region 9
(415) 947-4192


September 2003: Final Finding of Attainment for Carbon Monoxide

On September 9, 2003, EPA finalized its finding of attainment for the Phoenix area for the carbon monoxide national air quality health standard.

Contact Information

Wienke Tax (tax.wienke@epa.gov)
Office of Air Planning
EPA Region 9
(415) 947-4192

Pacific Southwest NewsroomPacific Southwest Programs Grants & FundingUS-Mexico Border Media CenterCareers About EPA Region 9 (Pacific Southwest)A-Z Index

Jump to main content.