PANAJI: The Goa State Pollution Control Board by this month will start preparing air quality index that will provide detailed information on air quality to the Central Pollution Control Board.
The CPCB has published information on air quality indices for 23 cities that helps in comparing pollution levels at a glance with a colour code, nomenclature and a numerical value based on ambient concentration values of air pollutants.
In India, air quality indices are determined based on the concentrations of eight pollutants – PM2.5 (fine, respirable particles), PM10 (coarse particles) sulphur dioxide (SO2), nitrogen dioxide (NO2) and carbon monoxide (CO), O3 (ozone), NH3 (ammonia) and Pb (lead).
The CPCB recently wrote to the GSPCB asking it to provide monthly data of air quality to calculate the AQI so as to put the information in the public domain.
The GSPCB has also been asked to prepare an action taken plan on areas which are exceeding ambient air quality standard.
An air quality index is a number used by government agencies to communicate to the public how polluted the air currently is or how polluted it is forecast to become. As the AQI increases an increasingly large percentage of the population could experience severe adverse health effects.
The analysis of AQI values in Goa for October 2015 indicated that 68 per cent AQI values are falling in good category, 28 per cent are in satisfactory and 04 per cent in moderate.
This indicates that the people in these areas have minimal impact of air pollution or minor breathing discomfort.
The CPCB seeks to put in the public domain the ambient air quality data of manual system from 612 stations covering 254 cities, including Goa, under the national air monitoring programme.
“Presently we measure air quality giving values that are difficult for a common person to grasp. But now following the CPCB direction we will maintain tabulations carried out by scientists on air quality, and based on that an index will be prepared and submit it to the CPCB,” said an official.
Under the NAMP the GSPCB monitors air quality at 16 locations on different parameters such as NOx, SO2, PM10 and PM2.5.
The annual monitoring report compiled by the GSPCB has said the air quality in the state has been deteriorating alarmingly as pollution levels went up as much as two times higher than normal in Vasco and Panaji, which have become the most polluted areas in the state mainly during November to March.
According to ambient air quality data of the GSPCB, the respirable particulate matter (RPM or PM10), which directly affects breathing, has gone up by over two times from the national ambiance air quality standard.
In 2014-15, PM10 was recorded in the state capital and Vasco at between 65-75 microgram per cubic metre (mpcm) while the prescribed standard is 100mpcm, but desirable is 60 mpcm. PM2.5, for which the prescribed standard is 60mpcm and desirable 40mpcm, also touched an alarming high at 120-141mpcm last year.
The main air pollutants for Margao and Vasco town emanated from construction and demolition activities followed by road dust but not due to vehicle emissions. This has resulted in rise of particulate matter 10 micrometres in size beyond the desirable limit of 60mpcm.
Looking at the data for the concentration of PM10 per cubic metre, Vasco recorded the highest level every year from November to March with the city recording on an average 70-80 microgram/cubic metre of RPM or PM10 and above 130 microgram/cubic metre of suspended particulate matter.