Air Quality Index (AQI)

• The color-coded AQI index was launched in India in 2014.
• Launched by the central government in 2014 as part of the Swachh Bharat campaign.
• a technical study was awarded to IIT Kanpur. 
• IIT Kanpur and the Expert Group recommended an AQI scheme.
• The pollutants measured include PM 10, PM 2.5, Nitrogen Dioxide, Ozone, Carbon, etc.

There are six categories of AQI, namely 

1. ‘Good’ (0-50), 
2. ‘Satisfactory’ (50-100),
3.  ‘Moderately polluted’ (100-200),
4.  ‘Poor’ (200-300), 
5. ‘Very Poor’ (300-400), and 
6. ‘Severe’ (400-500).

Source: Indian Express