Regulation & law · 19/11/2025Updated: 10/16/2026 · 1 min read

EPA Proposes Phoenix-Mesa Area Attained 2015 Ozone NAAQS by International Emissions

The Environmental Protection Agency (EPA) proposes that the Phoenix-Mesa nonattainment area in Arizona would have met the 2015 ozone national ambient air quality standards by August 3, 2024, due to international emissions. The EPA will finalize this action, fulfilling its statutory obligation to determine attainment.