Delhi’s citywide air-quality reading moved into India’s “poor” band Tuesday, while three monitoring sites remained “very poor,” showing that the improvement was uneven after Diwali.
The rolling Air Quality Index (AQI) stood at 299 at 10:30 p.m. ET Monday (03:30 UTC Tuesday), or 9 a.m. India Standard Time (IST), and at 297 at 3:30 a.m. ET Tuesday (08:30 UTC), or 2 p.m. IST, Hindustan Times’ analysis of Central Pollution Control Board (CPCB) data showed.
CPCB classifies readings from 201 to 300 as “poor” and those from 301 to 400 as “very poor.” The timed snapshots differ from the board’s daily bulletin, which gives the AQI at 4 p.m. IST.
At 3:30 a.m. ET Tuesday (08:30 UTC; 2 p.m. IST), the Indian Institute of Tropical Meteorology’s air-quality system showed 384 at IIT Delhi, 380 at Chandni Chowk and 380 at the IITM Pusa station. Press Trust of India reported that 23 of Delhi’s 57 reporting stations were in the “very poor” band Tuesday.
CPCB’s daily bulletin recorded Delhi’s AQI at 5:30 a.m. ET Monday (10:30 UTC; 4 p.m. IST). It drew on 47 of the city’s 59 stations and identified fine particulate matter, or PM2.5, as the prominent pollutant.
The Diwali-day AQI was 376 at 5:30 a.m. ET Sunday (10:30 UTC; 4 p.m. IST), before the evening fireworks. Hindustan Times’ analysis of CPCB data gives the 2026 Diwali-day reading; CPCB’s 2025 bulletin gives 345, and the Commission for Air Quality Management’s 2024 bulletin gives 328. The commission’s historical table lists 218 for 2023, 312 for 2022 and 382 for 2021, placing this year’s figure below 2021’s but above the readings for 2022 through 2025.
CPCB says prolonged exposure to air in the “poor” band can cause breathing discomfort for most people. For “very poor” air, it advises extra precautions for children, older adults and people who are ill.
The commission lists Stage III pollution controls as effective from Nov. 6, following earlier pollution measures across the National Capital Region. The next daily AQI reading is due at 5:30 a.m. ET Tuesday (10:30 UTC; 4 p.m. IST).
