Authorities in Delhi-NCR on Thursday lifted restrictions under Stage 4 of the Graded Response Action Plan (GRAP) following an improvement in air quality, according to an official order.
The Stage 4 curbs had been imposed on Wednesday due to stagnant winds, low temperatures, and foggy conditions that contributed to an Air Quality Index (AQI) of 396, classified as “Very Poor.”
Stage 4 measures include a ban on all construction activities, the entry of non-essential polluting trucks into Delhi, and mandatory hybrid classes for students, except those in grades 10 and 12. Additionally, non-essential diesel trucks and older diesel-run heavy goods vehicles registered under BS-IV norms were barred from entering the city, except for essential services.
The GRAP framework, implemented during winter months in Delhi-NCR, categorizes air quality across four stages: Stage 1 (Poor, AQI 201-300), Stage 2 (Very Poor, AQI 301-400), Stage 3 (Severe, AQI 401-450), and Stage 4 (Severe Plus, AQI above 450).
Delhi’s winter air quality typically deteriorates due to a combination of factors, including vehicle emissions, crop residue burning, firecrackers, and unfavourable weather patterns. Authorities continue to monitor the situation closely as pollution levels remain a significant challenge in the region.