Delhi's AQI Nears 400 Post-Diwali as Air Quality Worsens Across Adjoining Districts

Delhi's air quality index (AQI) neared 400 by 9 AM post-Diwali, while adjoining districts in Uttar Pradesh and Haryana recorded worsening pollution levels in the morning compared to the previous night.

The India Meteorological Department (IMD) had earlier predicted 'severe' category air pollution, defined as an AQI above 400, for both November 8 and November 9. The average AQI recorded on November 8 at 4 PM, representing the average of the previous 24 hours, stood at 376.

On Diwali night at 1 AM, Delhi's AQI was recorded at 372. This figure dropped slightly to 366 at 6 AM on Monday before worsening to 370 by 9 AM. Between 8 PM and 12 midnight on Diwali night, Delhi's average AQI remained between 370 and 373. However, data indicates that 18 to 21 monitoring stations reported an AQI exceeding 400 during the four-hour window when the impact of bursting firecrackers is typically at its peak.

Amid these developments, citizens took to social media to highlight AQI levels surpassing 1500 in several parts of the city, prompting questions regarding the accuracy and consistency of official government data.

Addressing the data gaps, Congress leader and former union minister Ajay Maken posted on X, stating that no PM2.5 data was recorded at 25 out of 39 stations in Delhi between 2:00 AM and 3:00 AM on the night of November 8–9. Citing Central Pollution Control Board (CPCB) data, he noted that these included stations that had successfully recorded data on the night of the previous Diwali.

According to the details shared, stations where data was missing included Anand Vihar, Ashok Vihar, Aya Nagar, Bawana, CRRI Mathura Road, Chandni Chowk, Dwarka Sector 8, IMD Lodhi Road, ITO, Jawaharlal Nehru Stadium, Mandir Marg, Mundka, NSIT Dwarka, Najafgarh, Narela, Nehru Nagar, North Campus DU, Okhla Phase 2, Punjabi Bagh, Pusa, R K Puram, Shadipur, Sirifort, Sri Aurobindo Marg, and Wazirpur.

Maken further stated that for the 9 stations with data available for both Diwalis during that hour, the average PM2.5 level was 576 µg/m³, which is 38.4 times the World Health Organization's (WHO) 24-hour limit. During the same hour on the previous Diwali, the level at those specific stations was recorded at 562 µg/m³, marking an increase of 2.5%.

Meanwhile, pollution levels also escalated in nearby regions. Bahadurgarh district in Haryana reported an AQI of 395 at 9 AM, up from 387 at 6 AM and 354 at 1 AM. Similarly, Gurugram district in Haryana recorded an AQI of 328 at 9 AM, compared to 312 at 6 AM and 291 at 1 AM.

"Environmental metrics like AQI and data transparency directly impact urban business operations, employee productivity, and regional economic activity. When critical infrastructure data shows gaps during peak pollution events, it creates uncertainty for businesses and policymakers attempting to plan sustainable urban interventions. Reliable data systems are essential for managing health crises and maintaining commercial continuity in major metropolitan regions." — Dr. Shishir Gupta, Founder & CEO, StartupLanes