Zürich Heubeeribüel PM2.5 (fine particulate matter) AQI is n/a - Zürich Heubeeribüel PM10 (respirable particulate matter) AQI is n/a - Zürich Heubeeribüel NO2 (nitrogen dioxide) AQI is n/a - Zürich Heubeeribüel SO2 (sulfur dioxide) AQI is 7 - Zürich Heubeeribüel O3 (ozone) AQI is 25 - Zürich Heubeeribüel CO (carbon monoxide) AQI is n/a -