The air quality in Delhi remained in the “severe” category on Saturday morning, two days after Diwali, showed real-time data by the System of Air Quality and Weather Forecasting and Research, or Safar.

The pollution level, however, decreased from 533 in the morning to 436 at 7 pm, data on Safar showed. PM10 levels were at 412 and PM2.5 at 286 in the national Capital at 7 pm, reported ANI.

The air quality index in Delhi was in the “severe” category on Friday as well, according to a bulletin by the Central Pollution Control Board. The city’s average air quality index in the 24 hours till 4 pm on Friday was 462, according to the agency.

An air quality index in the severe category affects healthy people and seriously impacts those with existing diseases.

The CPCB has predicted that on Sunday, the Punjabi Bagh area in Delhi will have the most polluted air, with PM2.5 levels of 475, while the RK Puram area will have the cleanest air, with PM2.5 levels in the moderate category at 196.

In an update on Saturday, Safar said that the overall air quality index, or AQI, in Delhi was likely to improve to “very poor” category as surface winds were getting stronger and dispersing pollutants in the air.

It also said that emissions from stubble burning accounted for 36% of the pollution share in Delhi, reported the Hindustan Times.

The agency said that the concentration of PM2.5 pollutants across the national Capital has become higher than in 2020 in the last 24 hours but it is “much less than that in 2018.”

Air pollution in Delhi typically worsens in October and November due to farmers burning stubble in neighbouring states, unfavourable wind speed and emission of fumes by vehicles in the city. Firecrackers ignited for Diwali add to the problem.

In September, the Delhi Pollution Control Committee had banned the sale and bursting of firecrackers up to January 1, 2022. Despite the ban and the deteriorating air quality, the residents of Delhi burst crackers on Diwali on Thursday.

Air quality in other states

Many places in Punjab and Haryana reported bad air quality on Friday after the bursting of firecrackers on Diwali, PTI reported.

Air quality was severe in Faridabad (454), Gurugram (473), Sonipat (411), Rohtak (449) and Hisar (421) in Haryana.

In Punjab, air quality was “poor” in Ludhiana (300) and Patiala (263), and “very poor” in Jalandhar (348).

Punjab reported 3,032 farm fires on the day of Diwali, according to the Hindustan Times. Out of the total cases of stubble burning in the state this year, 55% were reported in the past five days.

The air quality in Chennai fell to the “very poor” category on Diwali day on Thursday, the Hindustan Times reported.

On Friday, the air quality index in Mumbai was in the moderate category at 199, according to the CPCB. The air quality in Kolkata was in the poor category at 207.