What is the AQI?

The EPA and your State environmental agency measure pollution in the air. Then they use the Air Quality Index, or AQI, to tell the people about the air. An index can be a quick way to tell people how good or bad something is. The AQI uses colors, and numbers,and words to tell you about the air.

AQI Colors
AQI colors tell you how healthy the air is to breathe that day. The colors go from Green to Yellow to Orange to Red to Purple to Maroon, each color telling you that the air is less clean than the color before. Green is the best air quality.

Air Pollution and Health
One thing the AQI does is help you understand what the air quality around you means to your health. Each of the AQI colors has a word or phrase to go with it that tells you something about health. These are the colors and the health words that go with them.

AQI Colors - Health Word(s)
Green - Good
Yellow - Moderate
Orange - Unhealthy for Sensitive Groups
Red - Unhealthy
Purple - Very Unhealthy
Maroon - Hazardous