Trucks stopped from entering Delhi for three days from today

Two days after Diwali, toxic smog is choking the Capital as air quality index recorded "severe" levels on Friday with the concentration of harmful particulate matter hovering between four to five times the safe levels.

A "severe plus emergency" AQI essentially means that even healthy people may suffer from respiratory illnesses on prolonged exposure. The air quality was, however, better than it was in 2016 and 2017, indicating that the pollution caused by firecrackers was lower this year, said scientists.

Many others said the ceaseless bursting of firecrackers on Diwali night in violation of the court directive has highlighted the difficulties faced by government agencies in enforcing orders when laws are routinely flouted and accentuated the "large gap" between the law and the capacity to enforce it. Till November 10, construction activities have already been stopped and trucks, except those carrying essential goods, have been barred from entering the city.

According to System of Air Quality and Weather Forecasting And Research (SAFAR), the PM 2.5 level on Friday morning was 272 (severe) and PM 2.5 level was 422 (very poor). New Delhi topped the chart with air quality index (AQI) recorded at 420.

Delhi's air quality typically worsens in winter, as clouds of smoke from farmers' fires billow into the city and mix with industrial and traffic emissions to form a noxious cocktail.

According to SAFAR, the air quality in Delhi had "improved significantly" since Thursday, but the recovery was "slow due to low surface wind speed".

While other cities across north India recorded AQI scores of between 300 and 350, the air was significantly better in central and southern cities - with with the air in Thiruvananthapuram, Kerala, deemed "satisfactory" with a AQI score of only 64.

Last month, in a bid to control pollution, the Supreme Court allowed the use of "green" firecrackers for Diwali but only if they were let off between 8-10 pm.

Similarly, the PM10 level was recorded at 440 micrograms per cubic metre, making it four times the standard of 100.

Senior Delhi Police officials admitted "sporadic" breaches of the top court's order on bursting crackers beyond the 8pm to 10pm time frame fixed by it.

Vanessa Coleman