A maroon Air Quality Index indicates a health warning of emergency conditions, as everyone is likely to be affected.

Lingering wildfire smoke prompted a Code Orange in parts of Western Pennsylvania, impacting Allegheny County and Pittsburgh.

Air quality in Washington, D.C., and Northern Virginia remained at Code Red on Saturday as wildfire smoke kept fine-particle ...

Wildfire smoke from Canada is creating dangerous air quality across the DMV, with D.C. monitors showing Code Purple ...

Air quality alerts can change quickly during wildfire smoke events. Here’s what Code Orange and Code Red mean, who is most at ...

(WHTM) — If you thought air quality was bad in Code Red conditions, there are two worse levels. The Pennsylvania Department ...

Pittsburgh was under a Code Purple due to very unhealthy air quality on July 17.

Beth Skwarecki is Lifehacker’s Senior Health Editor, and holds certifications as a personal trainer and weightlifting coach. She has been writing about health for over 10 years. If you haven’t paid ...

The Pennsylvania Department of Environmental Protection (DEP) has declared a Code Purple Air Quality Alert for particulate matter (PM2.5) for Thursday for Northwest Pennsylvania, including Warren ...

The air quality will get worse before it gets better for most of Pennsylvania as smoke from Canadian wildfires continues to ...

BALTIMORE — Maryland is under a Code Red air quality alert Friday due to Canada and northern United States wildfire smoke ...

Canadian wildfire smoke has caused air quality in Washington DC to go beyond Code Red into Code Purple, "Very unhealthy" ...