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Flag Colors and Recommended Activity

Flags posted at participating schools and/or community organizations match AQI’s warning level colors, indicating the amount of pollution in the air and any possible associated health effects experienced within a few hours or days after breathing polluted air. ADEQ and some local districts calculate the AQI for four major air pollutants regulated by the Clean Air Act: ground-level ozone, particulate matter (PM10  and PM2.5) and carbon monoxide | Learn More About Pollutants >

Outdoor Activity Guide | View >
PM Fact Sheet |
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Ozone Fact Sheet | View >

For each of these pollutants, the Environmental Protection Agency (EPA) has established National Air Quality Standards to protect public health. If a warning is issued, the flag’s purpose is to protect the greater at-risk population.

Flag Colors

Green — Air quality is good. Weather permitting, it's a great day to be active outside.

Yellow — Air quality is fair, but may be a health concern to those who are unusually sensitive to air pollution. Watch for symptoms and reduce prolonged outdoor exertion.

Orange — Air quality is approaching unhealthy. Sensitive people, including children, older adults, pregnant women and those with heart or lung disease should take more breaks, lower outdoor activity intensity and watch for symptoms.

Red — Air quality is unhealthy. Take more breaks, shorten outdoor activities or choose less-intense activities. Consider rescheduling longer or more intense outdoor activities or moving them indoors.

Watch for Symptoms

Common symptoms to look out for are irritation of the eyes, nose and throat, including coughing, chest tightness and shortness of breath. You may need to take breaks, choose less-intense outdoor activities (e.g., walking instead of running), or move activities indoors. Air pollution may also make asthma symptoms worse and trigger attacks. Those with asthma should follow their asthma action plan and keep quick-relief medicine handy on moderate to unhealthy days.


Start a Flag Program at your school or organization | Learn How >