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