Air quality indexes indicate how polluted the air is, or forecast how polluted it could become, based on levels of five pollutants, according to the U.S. Environmental Protection Agency. Government ...

Air quality monitors from the Environmental Protection Agency are often used to guide policy and public health initiatives ...

The EPA measures regional air quality index (AQI) by how hazardous it is to the general public. Discover the AQI in your city by searching below.

This measure, based on data from the Environmental Protection Agency, evaluates states on the number of days the Air Quality Index in counties was not rated “good.” U.S. News calculated a ...

The six states cited in the lawsuit are home to more than 42 million people in regions with some of the nation’s worst air quality. Ground-level ozone — commonly called smog — is known to harm the ...