Delhi pollution: Reports of AQI crossing 2,000, official data differs

• Reports claimed Delhi's AQI crossed 2,000 after Diwali, but official CPCB readings showed a citywide AQI of 366 on Monday morning

• Delhi's AQI reached 371 on Sunday night, with 20 monitoring stations recording ‘severe’ pollution. Firecrackers worsened smog across several neighbourhoods

• GRAP-III restrictions remain in force as vehicular emissions, stubble burning and unfavourable weather continue to affect air quality

Delhi's air pollution situation came under renewed scrutiny on Monday following reports of extremely high AQI readings, with some claims suggesting pollution levels had crossed the 2,000 mark after Diwali celebrations. However, official monitoring data from the Central Pollution Control Board (CPCB) showed the city's average AQI at around 366 in the early hours, placing it in the ‘very poor’ category.

The national capital woke up to a thick blanket of smog on Monday, a day after Diwali, as firecracker emissions added to the existing pollution burden. The official citywide AQI stood at 366 at 6:15 am, while several monitoring stations recorded readings above 400.

Claims of AQI levels exceeding 2,000 have drawn attention to Delhi's deteriorating air quality. However, such figures cannot be directly compared with India's official AQI measurements, which follow a scale ranging from 0 to 500.

Private air-quality platforms may use different indices, including the US AQI, or report pollutant concentrations rather than the official Indian AQI. The measurement method and source must therefore be verified before treating readings above 2,000 as confirmed AQI figures.

On Sunday night, Delhi's average AQI reached 371 at 10 pm, with 20 of the 59 monitoring stations recording ‘severe’ air quality. Sonia Vihar registered the highest reading at 463, followed by Jahangirpuri at 450. Burari, Alipur and Punjabi Bagh were among the other badly affected areas.

The haze grew denser as firecracker bursting intensified across neighbourhoods, including Burari, Pitampura, Mayur Vihar and parts of Lutyens' Delhi. Residents reported reduced visibility, the lingering smell of burnt crackers and breathing difficulties.

The Commission for Air Quality Management (CAQM) had invoked Stage III of the Graded Response Action Plan (GRAP) across Delhi-NCR on November 6, imposing restrictions on construction activities and certain vehicles.

Experts have attributed the deteriorating air quality to vehicular emissions, firecracker smoke, stubble burning in neighbouring states and unfavourable weather conditions.

Low wind speeds and poor atmospheric ventilation have prevented pollutants from dispersing effectively, while PM2.5 has remained the predominant pollutant across much of the capital.

According to Delhi's Decision Support System, the transport sector was projected to contribute around 19 per cent of the city's pollution on Sunday, while stubble burning was estimated to account for 3.5 per cent.

With official AQI readings remaining elevated, health concerns persist, particularly for children, elderly people and those with respiratory conditions.

With agency inputs