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 ...

Learn what the air quality index (AQI) means, how it impacts your health, and how to stay safe when pollution is high.

Indicators like the Air Quality Index (AQI), commonly used to track air pollution levels, provide a rough sense of the ...

The Air Quality Index, set by the Environmental Protection Agency, is your guide to how bad the air quality is outdoors. The data that goes into the Air Quality Index comes from 5,000 air monitors ...

The Air Quality Index (AQI) is an index for reporting daily air quality. It tells you how clean or polluted your air is, and what associated health effects might be a concern for you. For more ...