How has Air Quality Improved in the Region?
MAG, in coordination with air quality partners at the Arizona Department of Environmental Quality, the Arizona Department of Transportation, Maricopa County, and Pinal County, has an impressive record in improving air quality. Below are a few of the region’s air quality achievements.
- In 2005, EPA redesignated the MAG region as a maintenance area for carbon monoxide. The region celebrated 20 years of maintenance with the standard in 2025.
- The MAG region has demonstrated attainment with four progressively stricter EPA ozone standards:
- In 2001, EPA determined the region attained the one-hour ozone standard of 120 parts per billion (ppb) and redesignated the area to maintenance in 2005.
- In 2014, EPA redesignated the region as a maintenance area for the eight-hour ozone standard of 80 ppb.
- In 2019, EPA determined the region attained the eight-hour standard of 75 ppb.
- In 2026, EPA determined the region would have attained the eight-hour standard of 70 ppb by August 2024, but for the impact from international emissions.
- EPA determined the region attained the PM-10 (dust) standard in 2014.
- EPA determined the region attained the 24-hour PM-2.5 (smoke) standard in Pinal County in 2019.