Air Quality Status in Pima County

Air quality has improved significantly in Pima County over the past two decades. This is due primarily to lower emissions resulting from federally mandated stationary source and motor vehicle emission standards; increased fuel economy and vehicle emission technology improvements, and countywide dust control ordinances. The increasing availability for residents to walk, bike or use transit instead of driving also has helped. Continuing to improve air quality in the region, however, remains a challenge based on the need to meet more stringent federal air quality standards.

Ground-level ozone and particulate matter are of key significance in the area, as levels of these air pollutants have exceeded the total concentrations recommended by the federal health standard in recent years. According to the U.S. Environmental Protection Agency, the use of electric vehicles, as well as electric lawn and garden equipment, help to keep air clean.

The EPA sets National Ambient Air Quality Standards (NAAQS) to protect public health and welfare; oversees regulations to reduce emissions of toxic air pollutants; and enacted the Regional Haze Rule to protect visibility and air quality at national parks and wilderness areas, such as Saguaro National Park in Tucson.

  • View real-time air quality monitors managed by the Pima County Department of Environmental Quality.
  • Pima County air quality monitors┬árecorded a value of 0.069 parts per million (ppm), based upon a three-year rolling average from 2018-2020. The EPA reviewed the ozone standard in 2020 and maintained the federal ozone NAAQS limit of 0.070 ppm set in 2015.