For nearly two decades the group has taken air quality data from the EPA and departments of natural resources from each state. Individual cities and counties are graded based on the latest EPA standards.
It turns out that warm weather played a big role in our air quality over the last few years.
"Of course, we can’t control the weather, which is why it’s so important to control the other pollutants that go into making up ozone - the nitrogen oxides and the VOCs (volatile organic compounds)," Dona Wininsky says.
She is the director of tobacco control and public policy for the American Lung Association’s Wisconsin chapter.
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