An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Summary of Vancouver Carbon Monoxide (CO) Attainment and Maintenance Plans


The Vancouver, Washington, portion of the Portland-Vancouver Air Quality Maintenance Area was designated as nonattainment for carbon monoxide (CO) and classified as moderate upon enactment of the Clean Air Act Amendments in 1990.

Washington submitted a CO maintenance plan on March 19, 1996, and EPA approved the plan on October 21, 1996 (61 FR 54560 (PDF)(4 pp, 126 K, About PDF)).


The plan relies on control strategies needed to assure maintenance of the National Ambient Air Quality Standards for Carbon Monoxide. The strategy focuses on an enhanced vehicle Inspection and Maintenance program.


  • 40 CFR Part 86, Federal Motor Vehicle Emission Control Program 
  • WAC 173-422, Motor Vehicle Emission Inspection

Contingency Measures

  • WAC 173-492, Motor Fuel Specifications for Oxygenated Gasoline
  • SWCAA 492-010 to 100, Oxygenated Fuels
  • WAC 173-422, Motor Vehicle Emission Inspection (early implementation credit)
  • WAC 173-433, Solid Fuel Burning Device Standards
  • SWCAA 400-111, Requirements for Sources in a Maintenance Plan Area

EPA Effective Date

October 21, 1996