Delhi Invokes GRAP Stage III as AQI Reaches 382 Ahead of Diwali

The Commission for Air Quality Management invoked Stage III of the Graded Response Action Plan across the National Capital Region on November 6 after Delhi's average Air Quality Index reached 382.

The Central Pollution Control Board reported the daily average AQI at 382, placing it in the very poor category and near the severe threshold of 401. Of 59 monitoring stations in Delhi, 30 recorded severe readings by morning. Rohini registered 473. Punjabi Bagh reached 465. RK Puram stood at 443. Several other stations crossed 420.

Stage III measures ban construction and demolition activity across the NCR, with limited exceptions. They prohibit the use of BS-III petrol and BS-IV diesel light motor vehicles in Delhi and in Gurugram, Faridabad, Sonipat, Ghaziabad and Gautam Buddha Nagar. Stone crushers, mining operations and hot-mix plants that do not use clean fuels must shut down. Diesel generator sets are restricted except for emergency services. Private firms are advised to allow work-from-home or hybrid arrangements. Classes up to grade 5 shift to hybrid mode in Delhi and several NCR districts.

The invocation came as a precautionary step. The CAQM sub-committee reviewed current conditions and forecasts from the India Meteorological Department and the Indian Institute of Tropical Meteorology. Those forecasts indicated the AQI would slip into the severe category in coming days. Unfavourable meteorological conditions limited pollutant dispersion. Stubble burning in neighbouring states and the approach of Diwali added further risk.

Delhi has recorded very poor air quality for several consecutive days. The 24-hour average stood at 369 the previous day and climbed through the week. PM2.5 concentrations reached levels not seen in the pre-Diwali period since 2019. Anti-smog measures already in place under Stages I and II, including water sprinkling and vehicle checks, continued alongside the new restrictions.

Health effects under these conditions include breathing difficulty, eye irritation and increased risk for people with existing respiratory or cardiac conditions. The Central Pollution Control Board classifies AQI above 300 as very poor and above 400 as severe. Stage III is normally triggered between 401 and 500, but the commission applied it early on the basis of the forecast.

Diwali falls within days. Firecracker use, even if restricted, has historically added to the particulate load. Authorities have not announced a full ban on firecrackers for this year, but enforcement of existing rules will determine the scale of the spike. Previous years have shown that post-Diwali AQI often enters the severe range within 24 to 48 hours of the festival.

The measures affect daily life across the region. Construction workers face lost days. Commuters on older vehicles must find alternatives. Schools must adjust schedules. The duration of Stage III depends on subsequent AQI readings. If the index falls and stays below 401 for a sustained period, the commission can revoke the stage.

Longer-term sources of the problem remain. Crop residue burning, industrial emissions, vehicle exhaust and dust from roads and construction sites all contribute. Meteorological factors such as low wind speed and temperature inversions trap pollutants. The Graded Response Action Plan provides short-term emergency steps. It does not replace structural changes in energy use, transport or agricultural practice.

Monitoring continues at multiple stations. Real-time data from the Central Pollution Control Board and the Air Quality Early Warning System will guide any further escalation to Stage IV, which includes additional restrictions on vehicle movement and industrial activity. Residents in the NCR face at least several more days of elevated pollution risk before any clear improvement.