Delhi’s air pollution 15 times WHO limit; parts of city reel under ‘severe’ pollution

After people burst firecrackers in Delhi on Deepavali night, clearly violating the existing ban that allows only green fireworks from 8 pm to 10 pm, the overall air pollution in Delhi on Tuesday morning (October 21, 2025) was nearly 15 times the limit set by the World Health Organization (WHO), as per official data.

People set off fireworks before and after 8pm on Monday night, October 20, 2025. Apart from green firecrackers, fireworks were also available in the city before window and Deepavali till 10 pm in the evening.

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According to Central Pollution Control Board (CPCB) data, the overall PM2.5 (key pollutant) level in Delhi was 228 micrograms per cubic meter at 6 am on Tuesday (October 21, 2025); this is 15.1 times the WHO permissible limit of 15 micrograms per cubic meter for a 24-hour period.

Delhi emerged as the world’s “most polluted” major city on Tuesday morning, October 21, 2025, according to live data from IQAir (Swiss air quality technology company) for over 120 cities. Delhi’s AQI was the worst on the list at 429, followed by Lahore (260) and Karachi (182).

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Delhi’s overall air quality was in the “very poor” category on Tuesday morning, October 21, 2025, with four out of 36 monitoring stations recording “severe” air pollution.

According to the CPCB, severe levels of air pollution “affect healthy people” and “seriously affect” those with existing diseases.

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Delhi’s 24-hour average air quality index (AQI) was 356 at 9 am on Tuesday, October 21, 2025, according to data from the Central Pollution Control Board (CPCB). Bawan, Burari, Jahangirpuri and Wazirpur were reeling under “severe” air pollution.

According to the CPCB, AQI between 51 and 100 is called “satisfactory”, 101 and 200 is “moderate”, 201 and 300 is “poor”, 301 and 400 is “very poor” and 401 and 500 is “severe”.

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Some other towns and cities in northern India also experienced “very poor” air quality, according to CPCB data.

Every winter, air pollution increases in Delhi-NCR and most parts of the greater Indo-Gangetic plains (IGP) due to meteorological factors such as low wind speed and temperature drop, and pollution from stubble burning and bursting of firecrackers during October-November.