
Delhi is sweltering the day after Diwali as pollution levels spiked at night, reaching the highest concentrations recorded in three years. Delhiites woke up to a thick layer of smog covering the National Capital on Tuesday, October 21.
Air quality has worsened despite the Supreme Court allowing only ‘green’ biscuits. Real-time data from the Delhi Pollution Control Committee (DPCC) showed that concentrations of particulate matter (PM) 2.5 and PM10 rose 15 to 20 times above safe limits at several stations, the Indian Express reported.
Air quality index in the “very poor” zone.
Several localities such as Anand Vihar, Dwarka Sector 8, Patparganj and Jahangirpuri recorded peaks above 1400 to 1800 µg/m³, which is 15-20 times the permissible standards.
The capital’s Air Quality Index (AQI) at 11 pm was 347, in the “very poor” category, according to data from the Central Pollution Control Board (CPCB). It remained largely unchanged at 346 at 6 a.m. Tuesday and climbed further to 359 by 11 a.m.
Data suggests that this year’s Diwali pollution levels were the highest in recent years, despite the promotion of ‘green’ crackers.
Delhi’s air quality on Diwali this year was worse than last year’s 328 in 2024 and higher than the previous two years – 218 in 2023 and 312 in 2022.
Worst affected areas
According to DPCC data, Anand Vihar recorded the highest PM10 concentration around 2:00 am, closely followed by Dwarka Sector 8, Patparganj and Jahangirpuri.
Stations like Mundka, Ashok Vihar and Okhla Phase 2 also reported readings exceeding safe limits in the late night hours.
At several locations, including Patparganj, Nehru Nagar, JLN Stadium and Okhla Phase 2, data was missing for several hours between 11:00 pm and 5:00 am, indicating possible instrument saturation due to extremely high particulate matter concentrations. The reading, which was resumed early in the morning, remained below safe limits.
Dr Mohan George, former additional director at DPCC, questioned the data gaps during the peak pollution window. “Why was CPCB’s continuous air quality monitoring available for several hours and why did most monitoring stations show missing data during the peak pollution window?” he asked.
“Many stations are missing data from 11pm to 6am… If it was ‘Green Deepawali’ then the public deserves to know what exactly they were breathing during the night,” George told the Indian Express.





