India, Nov. 9 -- Air quality in the national capital deteriorated further on Sunday morning, with the AQI climbing to 391 at 8 am - the highest this season officially and just short of entering the 'severe' category.

The capital has not officially recorded a 'severe' air day so far this year. The last such reading was on December 23, 2024, when the AQI was recorded at 406.

Though Sunday's AQI has eclipsed this season's peak of 388 at 10 am on November 2, the Commission for Air Quality Management (CAQM) has not invoked Stage 3 measures of the Graded Response Action Plan (GRAP).

Last December, the Supreme Court set a threshold of 350 for stricter pollution control rules to be invoked under GRAP, with Stage 4 to be invoked at 400.

The or...