Delhi pollution AQI works by measuring the air quality in the city based on five major pollutants: particulate matter (PM2.5 and PM10), nitrogen dioxide (NO2), ozone (O3), sulfur dioxide (SO2), and carbon monoxide (CO). The Air Quality Index (AQI) is a numerical value that represents the level of air pollution in the city. It is calculated based on the concentration of these pollutants in the air.
The AQI is categorized into six levels: Good, Satisfactory, Moderately Polluted, Poor, Very Poor, and Severe. The AQI value is calculated using a formula that takes into account the concentration of pollutants in the air. The formula is not explicitly mentioned in the provided evidence, but it is mentioned that the AQI value is calculated based on the concentration of pollutants.
When the AQI value reaches 450, it is considered severe, and the government implements measures to reduce pollution. In Delhi, when the AQI reaches 450, schools go hybrid up to class 5, meaning that students in classes 1 to 5 attend school in shifts to reduce the number of students on the roads at the same time.