Explanation:

In National Air Quality Index there are six AQI categories, namely Good, Satisfactory, Moderately polluted, Poor, Very Poor, and Severe.  The index will measure eight major pollutants, namely, particulate matter (PM 10 and PM 2.5), nitrogen dioxide, sulphur dioxide, ozone, carbon monoxide, nitrogen dioxide and sulphur dioxide.

The NAQI allows for easy dissemination of information pertaining to air quality and risks associated with it. The simplicity of the NAQI also makes it accessible to the common man. The use of the colour coded system  makes is easier for people to comprehend instantly.