On October 1, 2015, the EPA announced new primary and secondary ozone standards of 70 ppb. The previous standard was 75 ppb. The Arizona Dept. of Environmental Quality is required to submit attainment status boundaries to EPA by Oct. 2016. The air quality monitoring data from 2014-2016 will be used to determine if an area meets the new standards. The EPA will be issuing more technical guidance on how state and local agencies will implement these new standards.
Based on the most recent data available (2013-2015), Pima County would meet these new standards. Pima County ozone attainment status will not be known for some time.
For more information, please view the FAQ on the New Ozone Standards from PAG's Air Quality Program.