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 ...

What are the distinctions between Red and Purple? And which rules become stricter when shifting from one to the other? The answers provided by the CDPHE vary widely. In some cases, the ...

As the smoke spreads south and east, people are watching air quality meters and maps and seeing red - and purple. How did purple become even scarier than red? Here's NPR's Neda Ulaby. NEDA ULABY ...