India, Nov. 10 -- A grey haze hung heavy over Delhi on Monday - the air thick, the skyline blurred, and the city gasping for updates that never came. On one of the visually worst days of the pollution season, the air quality monitoring system in the national capital went silent, leaving residents guessing just how bad things were.

The Central Pollution Control Board (CPCB) stopped issuing Air Quality Index (AQI) readings on its Sameer app and website after 12.15pm, when the AQI stood at 345. Officials blamed a technical glitch for the lapse, assuring that the system would likely be restored by evening.

The Commission for Air Quality Management (CAQM) convened a meeting of its sub-committee on the Graded Response Action Plan (GRAP), stat...