India, Jan. 31 -- Delhi's air quality improved marginally but remained in the "very poor" category for a third straight day on Friday even as the minimum temperature rose a degree above normal to 9.5degC. An average air quality index (AQI) of 349 (very poor) was recorded at 9am compared to 363 (very poor) at 4pm on Thursday.

The Commission for Air Quality Management in the National Capital Region (CAQM) on Wednesday invoked Stage 3 measures of the Graded Response Action Plan (GRAP) after the AQI crossed 350. The measures include restrictions on non-essential construction and demolition, a ban on older diesel vehicles, suspension of mining operations, closure of stone crushers, etc. A CAQM meeting to lift the measures was expected in case...