Chandigarh: Chandigarh recorded relatively better air quality this Diwali compared with previous years, with the Air Quality Index (AQI) lower than last year at four of the six monitoring locations. Significantly, none of the locations recorded severe pollution levels, while air quality returned to the satisfactory category by 3 am on Monday after a temporary spike during the permitted firecracker-bursting hours.According to the Chandigarh Pollution Control Committee (CPCC), the AQI remained in the satisfactory category at most locations before the permitted bursting window of 8 pm to 10 pm on Sunday. Once firecracker activity began, pollution levels rose across all six monitoring stations, but the increase was short-lived.The highest AQI during the bursting window was recorded at Sector 25 (326), followed by PEC-12 (312), IMTECH-39 (310) and Sector 53 (304). These four locations briefly entered the very poor category. Sector 17 recorded an AQI of 170 and Sector 22 an AQI of 158, both in the moderate category.A comparison with Diwali 2025 shows improvement at Sector 22, where the AQI fell from 234 to 158; IMTECH-39, from 318 to 310; and Sector 17, from 183 to 170. Sector 53 remained unchanged at 304, while PEC-12 recorded the same AQI of 312 in both years. Sector 25 was the exception, with its AQI rising from 296 in 2025 to 326 this year.The performance was also encouraging when compared with the high Diwali pollution levels recorded in 2023 and 2024. Sector 22, for instance, recorded AQI readings of 392 and 395 in those two years, compared with 158 this Diwali. At Sector 53, the AQI declined from 453 in 2023 and 350 in 2024 to 304 in 2026.The improvement was supported by relatively better baseline air quality. On Nov 1, the AQI ranged from 77 at Sector 53 to 133 at IMTECH-39. On Diwali, pre-bursting readings were largely in the satisfactory category, although some locations were in the moderate category.The CPCC attributed the relatively controlled pollution episode to residents adhering to the prescribed two-hour bursting window and a considerable reduction in firecracker use compared with previous years. Favourable weather conditions also helped air quality recover after the bursting period.The committee said the public response reflected growing environmental awareness, particularly among young people and schoolchildren. It will continue its Green Diwali campaigns in schools and other awareness initiatives to encourage eco-friendly celebrations.BOX1: DIWALI AQI – FOUR LOCATIONS BETTER THAN 2025| Monitoring location | 2025 AQI | 2026 AQI || Sector 22 | 234 | 158 || IMTECH-39 | 318 | 310 || PEC-12 | 312 | 312 || Sector 17 | 183 | 170 || Sector 25 | 296 | 326 || Sector 53 | 304 | 304 |BOX2: HOW CHANDIGARH FARED OVER FOUR YEARS| Location | 2023 | 2024 | 2025 | 2026 || Sector 22 | 392 | 395 | 234 | 158 || IMTECH-39 | 360 | 306 | 318 | 310 || PEC-12 | 301 | 240 | 312 | 312 || Sector 17 | 138 | 287 | 183 | 170 || Sector 25 | 267 | 341 | 296 | 326 || Sector 53 | 453 | 350 | 304 | 304 |AQI categories: Satisfactory – 51-100; Moderate – 101-200; Poor – 201-300; Very Poor – 301-400; Severe – above 400.BOX3: Green DiwaliNo monitoring location recorded severe AQI this Diwali.Four of six locations improved over Diwali 2025.Sector 22 recorded the biggest year-on-year improvement, with AQI falling 76 points.Air quality returned to the satisfactory category by 3 am on Nov 9.The permitted firecracker window was restricted to 8 pm-10 pm.