Deepavali celebrations leave Chennai suffocated, Air Quality Index drops to severe in several localities

Besant Nagar, as usual, was the least polluted locality with an AQI of 345; the noise level values observed during the festival were higher than those recorded last year, with Tiruvottiyur being the highest at 79.7 dB

The city’s Air Quality Index (AQI) took a bad hit on Deepavali as it ranged between 345 and 786, making breathing difficult and visibility poor for those on the roads, according to data obtained by the Tamil Nadu Pollution Control Board (TNPCB) from the seven monitoring stations across the city.

Besant Nagar, as usual, was the least polluted area with an AQI of 345, not much of a change from last year’s 341. T. Nagar followed suit with 372, Tiruvottiyur with 436, Triplicane recorded 503 and Valasaravakkam posted 545, while Nungambakkam and Sowcarpet logged 563 and 786 respectively. The AQI values are usually the average of the major pollutant, which in this case was particulate matter of size 2.5 microns and below (PM2.5).

The AQI standards as set by the Central Pollution Control Board (CPCB) say when values are between 301-400, they may cause respiratory illness to people with prolonged exposure. If they are above 401, they are termed as severe and may cause respiratory impact even on healthy people and serious health impacts on people with lung/heart disease.

S. Surendran, an autorickshaw driver of Perambur, said the smoke entered his home after a vigorous session of firecracker bursting by his neighbours, even driving out the mosquitoes. “Ours is a small street, and the smoke was quite thick. There were announcements that people could burst firecrackers in open spaces and nearby grounds. But unless the Corporation tells us where it can be done, we cannot do so,” he added.

Former Member Secretary of TNPCB K. Karthikeyan said the timings meant for bursting firecrackers were too restrictive, which meant people tried use up all of their stock within a limited time, and this led to the concentration of smoke and heavy metals in the atmosphere. “There wasn’t much bursting during daytime after 7 a.m. The timings need to be revisited since the types of crackers too have changed. People are bursting more of the kind that need a dark sky,” he said.

As far as noise levels were concerned, Besant Nagar was quieter at 66 decibels (dB) when compared to Tiruvottiyur’s 79.7 dB. However, noise levels at all seven stations were higher than last year. T. Nagar stood at 77.7 dB, Nungambakkam at 78.6 dB, Triplicane at 73.3 dB, Sowcarpet at 71.1 dB and Valasaravakkam at 77 dB. According to the TNPCB, the noise level values observed on Deepavali were higher than the National Ambient Noise Standards – 55 dB during the day and 65 dB during night.

With restrictions on timings and the kind of crackers to be burst – green crackers with noise levels of less than 125 dB – the public, pollution managers and firecracker manufacturers have to put much thought into the celebrations this year.