Air Quality
Real-time Air Quality Index (AQI) for the United States. EPA data.
Air Quality Map
📊 Air Quality Index (AQI)
The Air Quality Index (AQI) is EPA's tool for communicating about outdoor air quality and health. The higher the AQI value, the greater the level of air pollution and the greater the health concern.
| Color | Level | AQI | Description |
|---|---|---|---|
| Good | 0 - 50 | Air quality is satisfactory, and air pollution poses little or no risk. | |
| Moderate | 51 - 100 | Air quality is acceptable. However, there may be a risk for some people, particularly those who are unusually sensitive to air pollution. | |
| Unhealthy for Sensitive Groups | 101 - 150 | Members of sensitive groups may experience health effects. The general public is less likely to be affected. | |
| Unhealthy | 151 - 200 | Some members of the general public may experience health effects; members of sensitive groups may experience more serious health effects. | |
| Very Unhealthy | 201 - 300 | Health alert: The risk of health effects is increased for everyone. | |
| Hazardous | 301+ | Health warning of emergency conditions: everyone is more likely to be affected. |
🔬 Five Major Pollutants
EPA establishes an AQI for five major air pollutants regulated by the Clean Air Act. Each of these pollutants has a national air quality standard set by EPA to protect public health:
Ground-level Ozone
O₃ - Main component of smog
Particle Pollution
PM2.5 and PM10 - Fine particles
Carbon Monoxide
CO - Colorless, odorless gas
Sulfur Dioxide
SO₂ - From fossil fuels
Nitrogen Dioxide
NO₂ - From vehicles and power plants