West Bengal, 16th November: Kolkata and Howrah saw marked improvement in the post-Diwali air quality this year compared to 2019 following the ban on fire-crackers imposed by the Calcutta High Court.

With fewer crackers this year, the noise level in the two cities were also much less compared to last year.

Data available with the West Bengal Pollution Control Board revealed that while the level of pollutants had shot up nine to 13 times above the daily permissible limits in Kolkata on Diwali night earlier, this the year it was around three times above the permissible limit.

The level of PM2.5 (pollutants which are at least 30 times finer than a human hair) had shot up to 768 micrograms per metre cube around midnight on Diwali in 2019. This year it reached a peak of 185 micrograms per metre cube around 12 midnight. The daily permissible limit is 60 micrograms per metre cube.

The Calcutta High Court had banned the use of fireworks during Kali Puja, Diwali and Chhath Puja in November this year across the state. The Supreme Court has refused to reverse a ban on sale or use of firecrackers in West Bengal during the festive month of November, saying that preservation of life should be the top priority in a country faced with a pandemic.

Similarly, in Howrah where air quality remains equally bad, pollution levels had shot up 11–15 times above the safe limits post-Diwali last year. This year it has shot up around three to five times.

Environment and health experts have warned that chronic exposure to air pollutants is associated with severe infections and higher mortality. They feel that lungs compromised due to pollution could lead to complications like pneumonia during Covid-19.

hat fewer crackers were used this year following the High Court ban was also evident from the fact that noise levels were also less this year. The average noise level was at least two decibels less this year in Kolkata.