GRAP-4 revoked in Delhi as AQI improves, stage-3 restrictions to continue

The Commission for Air Quality Management (CAQM) on Tuesday revoked stage 4 of the Graded Response Action Plan (GRAP) in the Delhi-NCR region following the improvement in air quality levels, reported ANI.

However, measures under stages 1, 2 and 3 will remain in force to manage pollution levels.

The decision was taken after Delhi's Air Quality Index (AQI) significantly improved to 369 (very poor) at 4 pm on Tuesday. In line with the Supreme Court's directives, stage 4 GRAP was invoked on December 16 after the AQI was recorded at 401 (severe).

The improvement in air quality was attributed to favourable metrological conditions, including improved wind speed, as per the air quality and weather forecast provided by the India Meteorological Department (IMD) and the Indian Institute of Tropical Meteorology (IITM).

Measures outlined in GRAP-4 encompass a prohibition on all construction activities, the restriction of non-essential polluting trucks from entering Delhi, and the mandatory transition of school classes -- excluding classes 10 and 12 -- to a hybrid mode.

The Graded Response Action Plan is a series of emergency measures established in the national capital region to address air pollution, tailored to the severity of the Air Quality Index.

The GRAP, a framework to tackle Delhi's winter pollution, classifies air quality into four stages: 4Stage I (Poor, AQI 201-300), Stage II (Very Poor, AQI 301-400), Stage III (Severe, AQI 401-450), and Stage IV (Severe Plus, AQI above 450).