AQI worsens again; Delhi air ‘severe’, Greater Noida at 474

The air quality index (AQI) in Delhi fell back in the “severe” zone on Wednesday morning after staying “very poor” for several hours the previous day. Greater Noida in Uttar Pradesh and Fatehabad in Haryana recorded the worst AQI in the country on Wednesday morning, at 474 and 442, respectively.

Of the 10 cities with the worst air quality as of 11 am, four were in Haryana, three were in Uttar Pradesh, and two in Rajasthan. Five cities recorded a “severe” AQI, as compared to four a day ago. In the national capital, Delhi, the 24-hour average AQI was 424, significantly higher than Tuesday's AQI of 395 recorded at 4 pm, data from the Central Pollution Control Board (CPCB) showed.

An AQI of over 400 is said to be “severe”, and according to the CPCB, can affect healthy people as well, while seriously impacting those with existing diseases.

Delhi's air quality had consistently languished in the 'very poor' category until Friday, 3 November, when it turned even worse, to “severe” (AQI above 400) for the first time this season.

The number of stubble burning incidents, a key factor behind the pollution at this time of the year, was recorded at 1,515 on 7 November in Punjab, down from the high of 3,230 recorded on 5 November. Haryana and Uttar Pradesh recorded 26 and 169 such incidents on 7 November.

The sharp increase in stubble burning incidents after 28 October has been instrumental in the worsening of the air quality in the region.

The Mint AQI tracker relies on the data released every hour by the CPCB, which in turn uses the data collected from several monitoring stations across the country. The AQI for a city is the average of the figure recorded at all stations in that city.