After remaining in the “severe” zone for six days on the trot, Delhi’s air quality improved slightly on Wednesday as a change in the wind direction reduced the contribution of stubble burning to the pollution, though it was still in the “very poor” category. The city recorded an air quality index (AQI) of 344.
The 24-hour average AQI was 476 on Tuesday. An AQI between 201 and 300 is considered “poor”, 301-400 “very poor” and 401-500 “severe”, while the AQI above 500 falls in the severe plus category.
Delhi had witnessed six consecutive “severe” air quality days till Tuesday. It had recorded seven such days in November last year.
The neighbouring cities of Faridabad (327), Ghaziabad (360), Noida (309), Greater Noida (340), and Gurgaon (288), which fall in the National Capital Region (NCR), also recorded their AQI in “poor” and “very poor” categories on Wednesday.
The Central Pollution Control Board (CPCB) ordered the closure of hot mix plants and stone crushers in Delhi-NCR till November 17 in view of a likely increase in pollution levels during the coming days, when a number of festivals will be celebrated.