The Air Quality — US Air Quality Index (US AQI) indicator shows the daily mean air quality index calculated according to the US Environmental Protection Agency (EPA) methodology. The US AQI converts concentrations of six key pollutants — PM2.5, PM10, O₃ (ozone), CO (carbon monoxide), SO₂ (sulphur dioxide), and NO₂ (nitrogen dioxide) — into a unified scale from 0 to 500.
| Category | AQI Range | Colour | Meaning |
|---|---|---|---|
| Good | 0 – 50 | Green | Satisfactory air quality, minimal risk |
| Moderate | 51 – 100 | Yellow | Acceptable, possible effects for very sensitive individuals |
| Unhealthy for Sensitive Groups | 101 – 150 | Orange | Health effects for sensitive groups |
| Unhealthy | 151 – 200 | Red | Health effects for general population |
| Very Unhealthy | 201 – 300 | Purple | Health alert, serious effects |
| Hazardous | 301 – 500 | Maroon | Emergency conditions |
The US AQI is the most widely used international standard for communicating air quality to the public.
Data come from the Open-Meteo Air Quality API (CAMS model). The variable used is us_aqi (composite US AQI index). The value is determined by the pollutant with the highest index. For each day, the average of hourly values is calculated.
| Code | Name | Provider | Type | Coverage | Availability |
|---|---|---|---|---|---|
WRD_OPNAQ_99 | Open-Meteo Air Quality API | Open-Meteo / CAMS | db | Global (Europe: 11 km) | From 2013 to present |
Daily average U.S. Air Quality Index (US AQI). Integrates PM2.5, PM10, O₃, CO, SO₂ and NO₂ on a 0-500 scale (EPA). Open-Meteo variable: us_aqi. Daily average of hourly values. Source: Open-Meteo Air Quality API (CAMS). Unit: dimensionless (0-500 scale).