Smog chokes city on Diwali

CHENNAI: Even as the city had a respite from rains by afternoon on the day of Diwali, allowing residents to burst crackers on the festive occasion, the atmosphere choked with 14 times higher than the standard concentration of particulate matter. Low wind velocity and higher humidity led to the formation of harmful sulphate aerosols, said officials of the Tamil Nadu Pollution Control Board (TNPCB), adding that these aerosols could cause severe lung disorders.Between 6 pm and 8.15 pm on Wednesday, the particulate matter (PM) level (less than 10 microgram) touched 1,423 micrograms per cubic metre compared to the standard 100 mg/m3 in Arumbakkam, which led the TNPCB officials to send out an appeal to the public to slow down on bursting crackers. This data and swift action in controlling air pollution was made possible by a mobile, instantaneous ambient air quality monitoring system, installed by the TNPCB for the first time this year.