There are six AQI categories -- good-satisfactory, moderately polluted, poor, very poor, and severe. Each of these categories is decided based on the ambient concentration values of air pollutants and their likely health impacts.
SAFAR had predicted that the air quality would be touching severe levels on Monday morning with the burning of an estimate of 50 per cent firecracker as compared to the average in 2017 and 2018, but the peak level of PM 2.5 is likely to be the lowest in the past 3 years after 2015 as surface winds in Delhi will greatly help in dispersion.
A meeting was held last week of the task force on Graded Response Action Plan (GRAP) for air pollution in Delhi-NCR. The meeting held at the Central Pollution Control Board (CPCB) was specifically called to review the likely air quality situation during the next few days.
Prashant Gargava, Member Secretary, CPCB had emphasised that the next few days will be challenging and in addition to the intense actions by implementing agencies, additional preventive measures may be required to check the deteriorating air quality.
Among the recommendations made was that the Supreme Court directions regarding fire crackers should be strictly enforced. Hot mix plants, stone crushers and construction activities such as earthwork, which have potential to generate dust should be banned between October 26-30 in Delhi and satellite towns such as Gurugram, Faridabad, Noida, Greater Noida, Ghaziabad, Sonepat and Bahadurgarh.
Also recommeded was the closure of coal-based industries with exemption to power-plants during this period.