FOX 5 New York on MSN

What is Code Purple air quality? What do Code Orange, Red and Purple mean?

Air quality alerts can change quickly during wildfire smoke events. Here’s what Code Orange, Code Red, Code Purple and Code ...
NPR

Purple is the new red: How alert maps show when we are royally ... hued

This week, millions of Americans are anxiously scanning air quality maps focusing on two colors: red and purple. Red indicates "unhealthy" air quality, and purple? "Very unhealthy." When did purple ...