Delhi’s air quality worsened sharply overnight, pushing authorities to activate stricter pollution control measures across the National Capital Region (NCR). The Air Quality Index (AQI), which stood at 349 at 4 pm on December 12, rose steeply during the night and touched 401 by 10 am on December 13, officially entering the ‘Severe’ category.

According to officials, the sudden deterioration in air quality was caused by slow wind speeds, a stable atmosphere, and unfavourable weather conditions that prevented the dispersal of pollutants. With pollution levels crossing the critical threshold, the Commission for Air Quality Management (CAQM) decided to implement Stage III of the Graded Response Action Plan (GRAP) with immediate effect.

What Triggered GRAP Stage III

The CAQM’s GRAP Sub-Commit

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