This regional site serves multiple counties. Use the dropdown below to view a specific county's data.
Annual Ozone Air Quality
This indicator gives a grade to each county in the U.S. based on the annual number of high ozone days. The American Lung Association (ALA) assigns grades A-F to counties (A=1; B=2; C=3; D=4; F=5), based on average annual number of days that ozone levels exceeded U.S. standards during the three year measurement period. The five-point grading scale was used for the distribution (Green = <2; Yellow = 2 - 3; Red = >3). The air quality data is collected by the EPA and summarized by the ALA.
Measurement Period: 2011-2013
learn more about the color range