CPCB releases National Air Quality Indices for 24 cities
The Central Pollution Control Board (CPCB) has released National Air Quality Indices (AQI) for 24 cities across India in the month of January 2016.
In the list Varanasi (Uttar Pradesh) and Muzzafarpur (Bihar) were on the top with an AQI value of 409 points each and were coded as ‘severe’ in terms of air pollution in January 2016.
- Faridabad (Haryana), Patna (Bihar) and Agra (Uttar Pradesh) were placed at 3rd, 4th and 5th position with 399, 388 and 372 points respectively.
- The national capital Delhi was placed at the 6th position with 362 points and was coded as ‘very poor’ in terms of air pollution. Earlier in December 2015, it was coded as ‘Poor’ in with 293 points.
Earlier in September 2015 and October 2015, Delhi was at the top in the AQI i.e. in terms of air pollution chart. The World Health Organization (WHO) also had earlier termed Delhi as one of the most polluted city in the world in terms of air pollution.
About National Air Quality Index
- The National AQI is published for every month by CPCB along with a numerical value and a colour code which helps in comparing air pollution levels in cities.
- It is determined on the basis of concentration of 8 pollutants, including Particulate Matter (PM 2.5, PM 10), sulphur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), ozone (O3), ammonia (NH3) and lead (Pb).
- The colour categories are classified into 6 categories depending upon numerical value as Good (0-50), Satisfactory (51-100), Moderately polluted (101-200), Poor (201-300), Very poor (301-400) and Severe (401-500).