Ozone in Louisville

How ground-level ozone is formedGround-level ozone is not emitted directly into the air, but is created when air pollutants called oxides of nitrogen (NOx) and volatile organic compounds (VOCs) are "cooked" by the sun on hot, windless days. 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.

According to the EPA, ozone pollution is a concern during the summer months because strong sunlight and hot weather result in harmful ozone concentrations in the air we breathe. Many urban and suburban areas throughout the United States have high levels of ground-level ozone. But many rural areas of the country are also subject to high ozone levels as winds carry emissions hundreds of miles away from their original sources.

Louisville is currently not meeting the recently strengthened 8-hour Ozone National Ambient Air Quality Standard (NAAQS). Although our community has made great progress in reducing overall air pollution, ozone continues to be a major challenge here.

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