Delhi's air quality improved to the "poor" category on Saturday, two days after Diwali, as strong surface winds helped disperse pollutants in the city. The average air quality index (AQI) in Delhi was recorded at 291 ("poor") at 8 a.m., an improvement from the AQI of 339 ("very poor") measured at 4 p.m. on Friday. This change came despite widespread violations of the city’s firecracker ban on both Thursday and Friday evenings. Before the celebrations on Thursday, the AQI was 328 at 4 p.m., remaining stable until 9 p.m. but then gradually worsening: reaching 330 by 10 p.m., 338 at midnight, 347 by 3 a.m., and peaking at 362 by 9 a.m. on Friday. Strong surface winds of 10-15 km/hr and above-average temperatures for this season then helped improve air quality. By noon on Friday, the AQI was 354, dropped to 339 by 4 p.m., and further improved to 314 by 10 p.m, as per reports.
According to the Central Pollution Control Board (CPCB), AQI levels range from "good" (0-50) to "severe" (over 400), with the "poor" and "very poor" categories spanning from 201 to 400. These figures reflect 24-hour averages, but real-time data showed PM2.5 levels skyrocketing up to 15 times the safe limit on Thursday night in some areas, exceeding 1,800 µg/m³ in certain residential zones. This underscores the severe impact of firecracker use on Delhi’s air quality, with the World Health Organization recommending a safe PM2.5 limit of 15 µg/m³, while India's National Ambient Air Quality Standards set it at 60 µg/m³.
Experts noted that strong winds aided in dispersing pollutants and are expected to continue through Saturday before winds are forecasted to calm on Sunday.
