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): ...

Those groups particularly sensitive to particulate matter in the air may want to limit time outside Friday and Saturday.

One possible reason for bad air quality in the city is a fire that broke out yesterday afternoon in Lancaster, Pennsylvania, ...

A wildfire erupted near Castaic Lake Wednesday, sending plumes of smoke into neighboring Ventura County areas. Here's what to ...

Wear a tight-fitting N95 mask at the bare minimum, but a P100 is better, experts say. Wear long sleeves, eye protection, closed-toed shoes and cut-resistant gloves. Clean or decontaminate anything ...

But air quality can vary on a hyperlocal scale, meaning the network of official sites is "fairly ... What doesn't AQI tell us ...