Air Quality Index

Resources

The purpose of the Air Quality Index (AQI) is to help you understand what local air quality means to your health. The higher the AQI value, the greater the level of air pollution, which means the greater the health concerns. It's an easy way to determine if you can enjoy the outdoors as usual or if you should consider planning an indoor activity to reduce exposure to polluted air.

AQI Look-up Table for Ozone concentrations
Ozone AQI Chart

Hazardous is 301+. The entire population is more likely to experience serious health effects and should avoid all outdoor exertion.

Very Unhealthy is 201 to 300. Everyone may experience more serious health effects and should avoid all outdoor exertion.

Unhealthy is 151 to 200. Everyone may begin to experience some adverse health effects and should limit prolonged outdoor exertion. Members of the sensitive groups should avoid prolonged outdoor exertion.

Unhealthy for Sensitive Groups is 101 to 150. People with heart and lung disease, older adults and children are at a greater risk and should limit prolonged outdoor exertion.

Moderate is 51 to 100. People who have a unique sensitivity to air pollution should consider limiting prolonged outdoor exertion.

Good is 0 to 50. No health impacts are expected when air quality is in this range.

AQI Look-up Table for PM2.5 concentrations
PM2.5 AQI Chart

Hazardous is 301+. The entire population is more likely to experience serious health effects and should avoid all outdoor physical activity, remain indoors and keep activity levels low.

Very Unhealthy is 201 to 300. People with heart and lung disease, older adults and children should avoid all outdoor physical activity. Everyone else should avoid prolonged or heavy outdoor exertion.

Unhealthy is 151 to 200. Everyone may begin to experience some adverse health effects and should limit prolonged or heavy outdoor exertion. Members of the sensitive groups should avoid prolonged outdoor exertion.

Unhealthy for Sensitive Groups is 101 to 150. People with heart and lung disease, older adults and children are at a greater risk and should limit prolonged or heavy outdoor exertion.

Moderate is 51 to 100. People who have a unique sensitivity to air pollution should consider limiting prolonged or heavy outdoor exertion.

Good is 0 to 50. No health impacts are expected when air quality is in this range.