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Ground-level Ozone Pollution

The ozone molecule (O3) is harmful to air quality, outside of the ozone layer. EPA regulations help states reduce ozone levels in their outdoor air.

November 7, 2018 - EPA issues final rule "Implementation of the 2015 National Ambient Air Quality Standards for Ozone: Nonattainment Area State Implementation Plan Requirements"

Ground-level Ozone Pollution

Ozone can be “good” or “bad” for health and the environment depending on where it’s found in the atmosphere. Stratospheric ozone is “good” because it protects living things from ultraviolet radiation from the sun. Ground-level ozone, the topic of this website, is “bad” because it can trigger a variety of health problems, particularly for children, the elderly, and people of all ages who have lung diseases such as asthma. Learn more about ground-level ozone.

Air Quality Where You Live

  • View current and forecasted air quality conditions across the U.S.
  • Explore current locations of wildfires
  • Review data from air quality monitors across the world

Visit AirNow.gov