On November 20, 2024, the air quality in New Delhi reached alarming levels, with the Air Quality Index (AQI) registering at 426, categorized as 'severe'. This condition poses significant health risks to both healthy individuals and those with pre-existing medical conditions.
The India Meteorological Department (IMD) reported that the minimum temperature dropped to 11.1 degrees Celsius, marking the coldest night of the season. Dense fog persisted throughout the morning, reducing visibility to 500 meters by 8:30 AM.
The Central Pollution Control Board (CPCB) confirmed that all but one of the 38 monitoring stations in Delhi recorded AQI levels in the 'red zone'. The Lodhi Road station, while not in the 'red zone', reported an AQI categorized as 'very poor'.
On Sunday, the air quality crossed into the 'extremely severe' category for the first time, prompting the implementation of Phase 4 restrictions under the Graded Response Action Plan (GRAP) on Monday morning. These measures include a complete ban on construction and demolition activities, as well as the suspension of in-person classes in schools.
The Commission for Air Quality Management (CAQM) has also enforced additional restrictions, allowing only BS-IV vehicles and those used for essential or emergency services to operate in Delhi and the adjoining National Capital Region (NCR). A ban on the entry of medium and heavy diesel commercial vehicles into the city has been imposed, with exceptions made only for vehicles transporting essential goods. Only electric and CNG trucks are permitted to operate, aside from vehicles providing essential services.
GRAP, first notified in 2017, classifies air quality into four phases based on severity: Phase 1 - 'Poor' (AQI 201-300), Phase 2 - 'Very Poor' (AQI 301-400), Phase 3 - 'Severe' (AQI 401-450), and Phase 4 - 'Extremely Severe' (AQI above 450).