The Clean Air Campaign issues Smog Alerts on days when the concentrations of either ozone or particle pollution -- or both -- are expected to reach unhealthy levels. You can receive these free in your e-mail.

Sign up to receive Smog Alerts in your inbox.

What Do the Colors and Numbers Tell Us?


Air Quality	Air Quality Index	Health Advisory
Good	0 - 50	Air quality is good. Enjoy activities.
Moderate	51 - 100	People who are unusually sensitive to air pollution should consider reducing prolonged or heavy exertion.
Unhealthy for Sensitive Groups	101 - 150	People with heart or lung disease (including asthma), older adults and children should cut back or reschedule strenuous activities.
Unhealthy	151 - 200	Everyone, especially people with heart or lung disease (including asthma), older adults and children should cut back or reschedule strenuous activities. Sensitive groups should avoid strenuous activities.
Very Unhealthy	201 - 300	Everyone, especially people with heart or lung disease (including asthma), older adults and children should significantly cut back on physical activities. Sensitive groups should avoid all physical activities.

Kinds of Pollution

There are two kinds of pollution in metro Atlanta -- ground-level ozone and particle pollution. Find out more about them here.

What Are the Hazards?

The hazards of poor air quality increase steadily as pollution levels increase. Each pollutant -- ozone or particle pollution -- carries its own associated health risks and effects.