Context:
Over the past few days, as the problem of air pollution in Delhi-NCR and surrounding areas has made its annual November-December appearance in policy debates and public discussion, the Air Quality Index (AQI) has been mentioned repeatedly.
Relevance:
GS III: Environment and Ecology
Dimensions of the Article:
- About Air Quality Index
- About National Ambient Air Quality Standards:
About Air Quality Index
- National Air Quality Index was launched by the Prime Minister in April, 2015 starting with 14 cities to disseminate air quality information.
- The AQI has six categories of air quality, viz Good, Satisfactory, Moderately Polluted, Poor, Very Poor and Severe with distinct colour scheme. Each of these categories is associated with likely health impacts.
- AQI considers eight pollutants (PM10, PM 2.5, NO2, SO2, CO, O3, NH3 and Pb) for which (up to 24-hourly averaging period) National Ambient Air Quality Standards are prescribed.
About National Ambient Air Quality Standards:
- The mandate provided to the Central Pollution Control Board (CPCB) under the Air (Prevention and Control of Pollution) Act empowers it to set standards for the quality of air.
- National Ambient Air Quality Standards (NAAQS) were notified in the year 1982, duly revised in 1994 based on health criteria and land uses.
- The NAAQS have been revisited and revised in November 2009 for 12 pollutants, which include
- Sulphur dioxide (SO2),
- Nitrogen dioxide (NO2),
- Particulate matter having size less than 10 micron (PM10),
- Particulate matter having size less than 2.5 micron (PM2.5),
- Ozone,
- Lead,
- Carbon monoxide (CO),
- Arsenic,
- Nickel,
- Benzene,
- Ammonia,
- Benzopyrene
-Source: The Hindu
