Delhi's air index to be 'poor' for next three days, says IMD

New Delhi [India], January 1 : India Meteorological Department Scientist Dr Vijay Kumar Soni said that the air quality of Delhi is to remain in the 'poor category' for the next three days.
"In Delhi, the air quality reached the 'severe' category in the last few days. After 30th December, there's an improvement in the index number. Right now, the air quality is in the 'poor' category. We hope there won't be much deterioration after that," Dr Soni said in a telephonic interview.
Soni added, "The deterioration of air quality is mainly because of meteorological conditions which are generally not favourable during the winter. The wind speed is low and light winds blow during winter. Also as the temperature is low, mixing height is also low during this season. Combined all the factors, this ventilation index comes down and that deteriorates the air quality."
Soni concluded that despite all these unfavourable conditions, air quality was much better during New Year's eve compared to the previous years.
When asked about the ban on construction work in Delhi, Soni said, 'Ban of construction work in Delhi has helped in controlling the pollution, particularly on 31st December. But when you see the last few years, specifically on 31st Dec & 1st Jan, the air quality deteriorates to the higher end of poor quality or is in a severe category. But this year it has improved because of the control measures that have been taken in advance."
The Air Quality Index from 0 to 100 is considered as good, while from 100 to 200 it is moderate, from 200 to 300 it is poor, and from 300 to 400 it is said to be very poor and from 400 to 500 or above it is considered as severe.