Nonattainment areas are classified by the Environmental Protection Agency (EPA) to have air quality monitoring data for criteria pollutants above the National Ambient Air Quality Standards (NAAQS), which are outlined in the Clean Air Act. These areas are designated conservatively and are not necessarily exceeding the NAAQS every day | See Today's Air Quality Forecast > 

The following is a list of the nonattainment areas listed by county:

Cochise County

• PM₁₀ — Paul Spur/Douglas | Learn More >

Gila County 

• PM₁₀ — Miami | Learn More >
• SO₂ — Miami | Learn More >
• SO₂ — Hayden | Learn More >
• Lead — Hayden | Learn More >

Maricopa County

• PM₁₀ — Phoenix | Learn More >
• Ozone — Phoenix | Learn More >

Pinal County 

• PM₁₀ — Hayden | Learn More >
• SO₂ — Hayden | Learn More >
• Lead — Hayden | Learn More >
• PM₁₀ — West Pinal | Learn More >
• PM₁₀ — Miami | Learn More >

Pima County

• PM₁₀ — Rillito | Learn More >

Santa Cruz County 

• PM₁₀ — Nogales | Learn More > 
• PM_2.5 — Nogales | Learn More >

Yuma County 

• Ozone — Yuma | Learn More >
• PM₁₀ — Yuma | Learn More >

Counties with no nonattainment areas at this time:

• Apache County
• Coconino County
• Graham County
• Greenlee County
• La Paz County
• Mohave County 
• Navajo County
• Yavapai County

National Ambient  Air Quality Standards

EPA Nonattainment Areas for Criteria Pollutants | Learn More >

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