Central Pollution Control Board Data Shows Mixed Air Quality Trends Across Indian Cities During Diwali

Central Pollution Control Board data indicates that Delhi-NCR remains a major pollution hotspot during Diwali, while cities like Chennai recorded a sharp increase in AQI. Conversely, cities such as Mumbai, Jaipur, and Delhi showed slight improvements compared to the previous year.

Data released by the Central Pollution Control Board (CPCB) as of 4 PM on November 9 outlines air quality index (AQI) readings across major Indian cities, capturing pollution levels during Diwali celebrations. The figures indicate that while Northern and Western India continue to concentrate high pollution levels, the geographical spread shows varying trends across metropolitan centers.

Delhi-NCR maintained its position among the most polluted locations, though Delhi's average AQI over the 24-hour monitoring window improved marginally from 351 in Diwali 2025 to 344 in Diwali 2026. The reading keeps the national capital firmly in the 'very poor' category, defined by CPCB as carrying serious respiratory and cardiovascular risks.

Beyond the capital, pollution levels shifted across other major urban hubs. Chennai recorded the sharpest increase among 10 major cities, with its AQI rising from 142 in 2025 to 199 in 2026, marking a 57-point deterioration. Patna also saw its AQI worsen from 226 to 280, while Bengaluru's AQI moved from 97 to 133, shifting it out of the satisfactory range.

In contrast, several cities reported improvements in their air quality metrics over the same period. Jaipur's AQI declined from 272 to 227, Mumbai's reading improved from 211 to 172, and Kolkata saw its index drop from 174 to 153.

An analysis of smaller urban centers reveals that Bahadurgarh topped the list of India's most polluted cities during Diwali 2026 with an AQI of 400, placing it at the threshold of the severe category. Seven out of the ten most polluted locations identified were situated in Haryana or the broader Delhi-NCR region. CPCB notes that high readings in these areas are typically influenced by factors such as firecracker emissions, agricultural and industrial activity, vehicular traffic, construction dust, and local topography that restricts pollutant dispersion.

On the other end of the spectrum, Aizawl recorded the lowest AQI in the country at 23, followed by Brajrajnagar at 48. Six of the ten cleanest locations identified in the dataset were located in Southern India, with Aizawl representing the North-East. Lower urban density and less concentrated emission sources contributed to these cleaner readings.

The CPCB classifies AQI levels from Good (0–50) up to Severe (above 400), with prolonged exposure to severe pollution posing health risks to both healthy individuals and those with pre-existing medical conditions.

"The latest CPCB air quality data highlights a critical operational reality for businesses and infrastructure in urban centers, particularly across Northern and Western India. Environmental compliance and sustainability are no longer peripheral metrics; they directly impact workforce productivity, health, and regional economic activity. As pollution trends fluctuate across cities like Delhi, Chennai, and Mumbai, enterprises must factor environmental resilience into their long-term business continuity and regional planning strategies." — Dr. Shishir Gupta, Founder & CEO, StartupLanes