Unión · Air quality

1. Good0–50Current category
2. Moderate51–100
3. Unhealthy for sensitive groups101–150
4. Unhealthy151–200
5. Very unhealthy201–300
6. Hazardous301–500+

A higher US AQI indicates more air pollution and greater health concern. Categories and pollutant concentration units are different measures.

All pollutants

PM1

2 µg/m³

PM2.5

2 µg/m³

PM10

3 µg/m³

Ozone

50.3 µg/m³

Nitrogen dioxide

1 µg/m³

Sulfur dioxide

0 µg/m³

Carbon monoxide

98.7 µg/m³

European AQI (separate scale)

2