The real-time air quality in Saint Louis is 21 (GOOD) AQI now. This was last updated 3 hours ago .

The current concentration of PM2.5 in Saint Louis is 5 (µg/m³). The World Health Organisation (WHO) recommends 15 µg/m³ as the threshold concentration of PM2.5 for 24 hrs mean. Currently, the concentration is 0.20 times the recommended limit.

Generally, the air quality at Saint Louis 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 Saint Louis 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 Saint Louis is as dangerous as outdoor pollution, because the air pollutants come inside the houses or buildings through doors, windows and ventilation.

In Saint Louis, 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 Saint Louis is very high. Proper ventilation is highly recommended only when outdoor air quality is improving and moderate AQI range.