Overview
- Delhi’s air deteriorated sharply after Diwali weekend celebrations, with the citywide AQI in the 'very poor' to 'severe' range on Monday and dozens of monitoring stations reporting readings above 400.
- The Supreme Court allowed limited hours for certified 'green' crackers over the festival but officials and reporters documented widespread bursting beyond the permitted windows and weak on‑the‑ground enforcement.
- Analysts and opposition politicians flagged data gaps in the Central Pollution Control Board records, with independent researchers reporting hundreds of missing hourly PM2.5 observations and private monitors recording much higher localized peaks.
- The poor air caused immediate health and visibility problems that prompted advisories and short‑term measures such as shifting some school classes online and urging people to work from home.
- Authorities had preemptively invoked GRAP Stage III and warned of continued severe pollution as stubble burning in Punjab and Haryana, vehicle and industrial emissions and unfavourable weather combined to amplify particulate spikes.