Code red warns of fire. At Children’s National Hospital in Washington, D.C., staff have added another: code dark, for a cyberattack.

Code Yellow” and “Code Red” are terms that put parents and students on high alert, but not everyone really knows what they mean.

7:15 a.m. — Widespread Code Red and Purple air quality, worst in years Residents in the Washington and Baltimore regions are awakening to their worst air quality in years.