The real-time AQI in this city is 70 (MODERATE) now. This was last updated 3 hours ago .

The current concentration of PM2.5 at Sion is 21 (µg/m³). The World Health Organisation (WHO) recommends 25 µg/m³ as the threshold concentration of PM2.5. Currently, the concentration is 0.84 times the recommended limit.

Generally, the air quality at Sion starts deteriorating in late October. The winters are the worst-hit season in terms of air pollution.

You should wear a good N95 mask when you go outdoor in Sion until the AQI is improving upto moderate range.

Office going people should avoid personal vehicles and use public transportations or carpooling.

(i) The primary causes of outdoor air pollution are solid, liquid particles called aerosols & gase from vehicles emissions, construction activities, factories, burning stubble & fossil fuels and wildfire, etc.

(ii) Main causes of indoor air pollution are harmful gases from cooking fuels (such as wood, crop wastes, charcoal, coal and dung), damp, mould smoke, chemicals from cleaning materials, etc.

Indoor air pollution in Sion is as dangerous as outdoor pollution, because the air pollutants come inside the houses or buildings through doors, windows and ventilation.

In Sion, you must use an air purifier or fresh air machine at home or office indoor and close all the doors, windows and ventilations when the outdoor air quality index (aqi) in Sion is very high. Proper ventilation is highly recommended only when outdoor air quality is improving and moderate AQI range.