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

If you have been hearing about poor air quality in New York City Friday, you can breathe a deep sigh of relief (literally): our air quality is fine. Typical air quality in the city falls below 50 on ...

But as the fires burned through houses, cars and industrial areas, they spewed out vast amounts of smoke, ash and noxious gases that spread across the city. Indicators ... temporal density to tell us ...

The Air Quality Index measured 156 near Forks, Washington, and received a rating of "unhealthy," meaning some members of the general public may experience health effects and members of sensitive ...