Oct 3, 2022 - News

Metro Phoenix's ozone pollution has gotten more severe, EPA says

Maricopa County average annual high-ozone days
Data: American Lung Association State of the Air report; Chart: Sara Wise/Axios. The American Lung Association considers 3.2 high ozone days a "passing" grade for air quality.

The EPA reclassified the Valley's ozone pollution as "moderate" last month, which is more severe than its previous ranking of "marginal."

Why it matters: Ozone is harmful to breathe. It aggressively attacks lung tissue, which can cause respiratory diseases, according to the American Lung Association.

Of note: The Phoenix area has significantly decreased the number of high ozone days since its peak in 2000.

  • Yes but: The ALA's 2022 State of the Air report still ranked the Phoenix metro area as the fifth worst for ozone pollution compared to other metro areas.

Flash back: In 2015, the EPA tightened the ozone pollution standard to 70 part per billion, from 75.

  • Our region, which includes all of Maricopa County and parts of Pinal County, had until August 2021 to meet the new standards. It did not.

What's next: The new classification requires the region to take more intense action to bring down ozone pollution.

  • For example: Any large new developments — or major expansions to existing facilities — will be required to offset every ton of emissions by 1.15 tons.

Be smart: The Maricopa Association of Governments offers some tips for everyday residents to combat ozone pollution:

  • Fuel your vehicle after dark or during cooler evening hours.
  • Use water-based paints, stains, finishes and paint strippers.
  • Eliminate wood-burning in fireplaces, stoves and outdoor fire pits.

Go deeper: Phoenix wants 280,000 EVs on its streets by 2030


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