Partly as a result of smoke from crackers, the overall air quality index (AQI) in Delhi jumped to 574 which falls in the "severe-plus emergency" category, according to data by the Centre-run SAFAR (System of Air Quality and Weather Forecasting And Research).
A "severe plus emergency" AQI essentially means that even healthy people may suffer from respiratory illnesses on prolonged exposure. This air will seriously affect those with ailments, according to the advisory issued by SAFAR.
A new SAFAR report said the severe conditions would prevail for the next two days.
"Even if 50 per cent of the total load of toxic fire crackers as compared to Diwali-2017 is added, the prevailing weather conditions will aggravate the high smoke level and make air quality to persist in SEVERE range for at least 2 day (8-9 Nov 2018)," the SAFAR said in its report.
"This scenario is likely to hold the locally generated crackers emissions within the NCT, slowing down the dispersion, resulting in increased levels of PM2.5 and PM10 pollution," it added.
The widespread burning of firecrackers in neighbouring states of Delhi is also adding to the pollution woes of the national capital apart from stubble burning, the agency said.
"The fire counts are seen to be very high but it is a combination of stubble burning and widespread firecrackers in that region and need not be confused with stubble only fire," it said in a report.
The report on the widespread burning of firecrackers comes even as the Supreme Court has fixed a two-hour time period, from 8 pm to 10 pm, for bursting of crackers on Diwali and other festivals.
A thick haze settled over Delhi Thursday as firecracker emissions mixed with the air.
The MeT department said mist and smog cover was reported at all three airports of the city with the lowest visibility of 400-700m recorded between 7 am and 9 am.
The Supreme Court has allowed bursting of firecrackers from 8 pm to 10 pm only on Diwali and other festivals. The top court also allowed manufacture and sale of just "green crackers" which have low emission of light, sound and harmful chemicals.
The court said the police should ensure that there was no sale of banned firecrackers and in case of any violation, the Station House Officer (SHO) of the police station of the area would be held personally liable and this would amount to committing contempt of the court.
But despite the order, certain places recorded violations where firecrackers were burnt before and after the set time frame.
The areas where the violations were recorded included Mayur Vihar Extension, Lajpat Nagar, Lutyens' Delhi, IP extension, Dwarka and Noida Sector 78.
The police admitted that violations were observed and it would take serious legal action against the people violating the apex court order. They said they were continuously patrolling the areas to check for violations.