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.

Public Hearing on EPA's Response to Clean Air Act 176A Petition from 9 States Rescheduled for April 13, 2017

Ozone Pollution

Ground level or "bad" ozone is not emitted directly into the air, but is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight. Emissions from industrial facilities and electric utilities, motor vehicle exhaust, gasoline vapors, and chemical solvents are some of the major sources of NOx and VOC. Breathing ozone can trigger a variety of health problems, particularly for children, the elderly, and people of all ages who have lung diseases such as asthma. Ground level ozone can also have harmful effects on sensitive vegetation and ecosystems.