Air Quality Index
Levels of Health Concern |
Numerical
Value |
Meaning |
Good |
0 to 50 |
Air quality is considered satisfactory, and air pollution poses little or no risk |
Moderate |
51 to 100 |
Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution. |
Unhealthy for Sensitive Groups |
101 to 150 |
Members of sensitive groups may experience health effects. The general public is not likely to be affected. |
Unhealthy |
151 to 200 |
Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects. |
Very Unhealthy |
201 to 300 |
Health warnings of emergency conditions. The entire population is more likely to be affected. |
Hazardous |
301 to 500 |
Health alert: everyone may experience more serious health effects |