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Viseu, Portugal

Oliveira de Frades · Air quality

Wednesday, Nov 4 · Europe/Lisbon

Oliveira de Frades air quality

US air quality index

51

Moderate

US EPA scale

  1. Good0–50
  2. Moderate51–100Current category
  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.

Understand the EPA scale

All pollutants

PM1
29 µg/m³
PM2.5
32 µg/m³
PM10
34 µg/m³
Ozone
70.7 µg/m³
Nitrogen dioxide
12 µg/m³
Sulfur dioxide
1.3 µg/m³
Carbon monoxide
366 µg/m³
European AQI (separate scale)
2