The Centre's air quality panel for Delhi-NCR on Thursday lifted the stage 4 restrictions of the Graded Response Action Plan (GRAP) after the dip in pollution levels, PTI cites the official order. The restrictions were imposed on Wednesday due to calm winds, low temperatures, and foggy conditions that allowed pollutants to accumulate, resulting in an air quality index (AQI) of 396 by the evening.
However, yesterday evening, parts of Delhi-NCR received light rain reducing visibility and disrupting more than 100 flights and 26 trains.
Stage 4 measures include a ban on all construction activities, restrictions on non-essential polluting trucks entering Delhi, and mandatory hybrid learning for school classes, excluding grades 10 and 12. Additionally, non-essential diesel trucks are barred from entering Delhi, and Delhi-registered BS-IV and older diesel heavy goods vehicles are prohibited, except those providing essential services.
On Wednesday, the India Meteorological Department and the Indian Institute of Tropical Meteorology predicted that AQI may breach the 400 mark soon. IMD had forecast cloudy skies throughout the day in Delhi, with light rain or drizzle likely in some areas today. It reported a minimum visibility of 200 metres in moderate fog with calm winds at Safdarjung and 150 metres in dense fog with calm winds at Palam around 5:30 AM on Wednesday.
The weather department had also issued an orange alert for the national capital, with dense to very dense fog reported in several areas. "An orange alert is issued for bad weather that can disrupt rail and road services. It has asked people to exercise caution while driving or travelling during foggy conditions, ensure the use of fog lights for better visibility, and stay updated on schedules by coordinating with airlines, railway authorities, and state transport services to avoid disruptions," the IMD said.
Amid winter, the Delhi-NCR region implements GRAP measures based on air quality levels, classified into 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).