A thick layer of smog engulfed Delhi late on Wednesday and early on Thursday, with the air quality deteriorating to the "very poor" category as Delhiites continued to burst Diwali firecrackers long after the deadline set by the Supreme Court.
The overall Air Quality Index (AQI) was recorded at 302 at 11pm, which fell in the very poor category, according to the Central Pollution Control Board (CPCB).
Admitting "sporadic" breaches of the Supreme Court order on bursting Diwali crackers beyond the time frame of 8pm to 10pm fixed by it, senior Delhi Police officials said, "We are monitoring the situation."
"There have been sporadic cases of violations. In some areas, people have been found burning firecrackers beyond 8pm-10pm time frame. The exact number of violation is yet to be ascertained. But, we will take strict action against them," said a Delhi Police official.
They said they had been continuously patrolling the city to check for violations during Diwali festivities.
The Supreme Court had allowed bursting firecrackers only between 8pm and 10pm on Diwali, while permitting manufacturing and sale of only "green crackers" with low emission of light, sound and smoke.
The Supreme Court had asked police to ensure that there was no sale of banned firecrackers and in case of any violation, the station house officers of the police stations concerned would be held "personally liable".
This would amount to committing the contempt of court, the Supreme Court had warned.
Some of the areas where the people were seen bursting Diwali crackers beyond the Supreme Court-stipulated time frame included Mayur Vihar Extension, Lajpat Nagar, New Delhi's Lutyens Zone, IP Extension, Dwarka and Noida-Sector 78. The intensity of the crackers burst before 8pm, however, remained low.
But as the Diwali festivities picked up, the faint echo of crackers started growing louder.
Bursting of crackers beyond 10pm was reported from areas like Mayur Vihar Extension and many South Delhi localities.
The overall air quality index was recorded at 296 at 10pm after the Supreme Court deadline to burst crackers came to an end.
The AQI at 7pm, was 281, which rose to 291 at 8pm and escalated further to 294 at 9pm, the Central Pollution Control Board data revealed.
The online indicators of the city's pollution monitoring stations indicated 'poor' and 'very poor' air quality as the volume of ultra-fine particulate materials PM2.5 and PM10 in the air, which enter the respiratory system and manage to reach the bloodstream, sharply rose after 8pm.
The pollutants had breached the corresponding 24-hour safe limits of 60 and 100, respectively, by up to three times.
While it was difficult to quantify the immediate effect of the ban on firecrackers, residents across the national capital felt the beginning of Diwali day festivities was promising with the neighbourhoods reporting much lesser noise and smoke till about 8pm.
According to the CPCB data, the 24-hour rolling average of PM2.5 and PM10 were 146 and 275 micrograms per cubic metre, respectively.
The SAFAR (System of Air Quality and Weather Forecasting And Research) had forecast "bad" air quality on Thursday even if partially toxic Diwali crackers, as compared with 2017, were burned.
The situation was similar, if not worse, in the neighbouring regions of Delhi such as Gurgaon, Noida and Ghaziabad, where Diwali crackers were burst as usual, raising question marks on the efficacy of the administration in enforcing the Supreme Court's ban.
A 'very poor' air quality index (AQI) essentially meant that people may suffer from respiratory illnesses on prolonged exposure to such air. If the air quality dips further, the AQI will turn 'severe', which may trouble even those with sound health conditions and seriously affect those with ailments.
The Centre, in collaboration with the Delhi government, had launched an aggressive 10-day-long 'Clean Air Campaign' from November 1 to 10 to monitor and report polluting activities.
About 52 teams deployed under the campaign had been visiting different parts of Delhi and adjacent towns of Faridabad, Gurgaon, Ghaziabad and Noida.
The teams comprised the local sub-divisional magistrate (SDM) as the team leader besides senior officials from the Ministry of Environment, Forest and Climate Change (MoEFCC) and representatives from the CPCB, Municipal Corporation of Delhi (MCD) and the DPCC.
