During the 2022 Diwali, Kolkata witnessed 'Good' AQI as compared to 'Moderate' or 'Very Poor' for metro cities like Mumbai, Delhi, Bengaluru and Chennai, the WBPCB said in a statement on Thursday.

It said that improved air quality data and reduced noise level figures show that Kolkata in particular and West Bengal as a whole has witnessed the cleanest Diwali in recent times. "Barring violations reported from few pockets of the state, persistent awareness campaigns, vigilance from the WBPCB's Integrated Command and Control Centre (ICCC) coupled with some influence of the passing Cyclone Sitrang have contributed to such improvement in celebrating the cleanest of Diwali in 2022," the state PCB said.

While in Kolkata, the highest air quality index (AQI) stood at 49 on Diwali, it was 330 in Delhi, 130 in Mumbai, 158 in Bengaluru and 261 in Chennai, the WBPCB said. While the cyclone had its effect in Kolkata, North 24 Parganas and South 24 Parganas, West Bengal has witnessed "Good" AQI across every district, it said.

Sitrang passed by the West Bengal coast before making landfall in neighbouring Bangladesh, but did bring rain and strong wind in the coastal districts of North and South 24 Parganas and Kolkata, dampening Diwali festivities on October 24.

The WBPCB said that awareness drives through various platforms like radio, meetings, social media and newspapers had a collective effect towards reduced sale and bursting of illegal firecrackers, which in turn ensured better ambient air quality.

The police arrested 270 persons for illegal firecracker bursting or violating other pollution norms during Diwali festivities till October 27 across the state, with Kolkata topping the list at 92, followed by 50 in Siliguri and 25 in Purulia, it said.

A total of 14,892 kg of illegal firecrackers were seized, with Kolkata topping the list at 9,695 kg, it said. Seizure of firecrackers in the state went up two times this year compared to 2019, while arrests have increased 18 times, the pollution control board said.

The WBPCB said that most of the locations in the state had reduced noise levels both during day and night time in 2022 even when compared to pre-Covid 2019, when no restrictions were in place, claiming that this is direct fallout of awareness and enforcement.

It said that there has been a slight increase in overall noise levels in 2022 as compared to 2020 and 2021, when the festivities were observed under strict Covid-19 restrictions.

Stating that the night-time noise levels in Kolkata were lower than the day-time noise levels during the Diwali festivities this year, the PCB said that it hints at ambient noise due to honking or construction being more prevalent than firecracker noise.

It said that measures are being planned to contain day-time noise.

(With PTI Inputs)