The Air quality level was much better in Kolkata on the evening of Kali puja and Diwali on Saturday, compared to that on the festival day last year, as bursting of firecrackers was much less following a high court order, an official of the West Bengal Pollution Control Board (WBPCB) said.
The Air Quality Index (AQI) measured at the automated air monitoring station in Rabindra Bharati University in north Kolkata was 226 (PM 2.5) till late evening this year, while it was beyond 700 in 2019, he said.
An AQI between 101 and 200 is considered moderate, 201-300 ''poor'', 301- 400 ''very poor'' and 401-500 ''severe'', while the AQI above 500 falls in the severe plus category.
The AQI hovered between 300 and 500 in pockets across the city last year, while it was 151 at Bidhannagar in east Kolkata, 142 at Ballygunge in the southern part of the city and 115 at Victoria air station in central Kolkata on Saturday, the official said.
"There were very sporadic one or two cases of bursting of firecrackers and fireworks," he said.
The Calcutta High Court had last week ordered a blanket ban on the use of fireworks in West Bengal during Kali puja, Diwali, Chhath and other pujas during this festive season to curb pollution amid the COVID-19 pandemic. In the previous years, only firecrackers that emit over 90 decibels of sound were not allowed by the WBPCB, and there was no ban on fireworks that emit light.
Asked on complaints received from across the state about the violation of the high court order, the official said, "Our control room is monitoring the situation 24x7. So far the situation remains largely under control.
Environmentalist S M Ghosh said, "As the sound of crackers is less so far, it seems there has been some effect of the blanket ban on fireworks. However, the situation needs to be monitored and analysed tomorrow morning to arrive at a conclusion."
However, the AQI readings on Saturday evening were a bit higher across the city compared to those in the past few days, the WBPCB official said.
"The climatic conditions in mid-November, the density of particulates in the air, the higher number of smaller vehicles on festival evenings, higher commercial activities might have contributed to the spurt in the AQI level. We have to analyse," he said.