With the implementation of stage four restrictions under the Graded Response Action Plan (GRAP), Delhi’s air quality has deteriorated to alarming levels, hovering around the ‘severe+’ category, where the Air Quality Index (AQI) exceeds 450.
This decline in air quality is occurring even after relaxations were introduced on December 5, following the end of the primary stubble burning period, which concluded on November 30.
On Wednesday at 11 a.m., the Central Pollution Control Board (CPCB) reported an average AQI of 440, slightly down from 442 recorded at 8 a.m. Out of the 37 monitoring stations that provide data, 19 registered AQI levels above 450, with Anand Vihar reporting the highest at 484. Only four stations displayed an AQI below 400, while the other 13 reported figures ranging between 410 and 450.
The GRAP for the National Capital Region (NCR) of Delhi is categorized into four stages based on air quality: Stage 1 indicates a “poor” AQI (201-300), Stage 2 signifies “very poor” air quality (301-400), Stage 3 denotes “severe” (401-450), and Stage 4 pertains to “severe plus” (AQI above 450).
The Commission for Air Quality Management (CAQM) in NCR invoked the GRAP IV restrictions effective immediately late on Monday. The Union Environment Ministry initially announced GRAP III restrictions at 7 p.m., only to follow up later that evening with the implementation of GRAP IV measures.
On December 5, the Supreme Court allowed some relaxations of the GRAP IV restrictions—previously enacted on November 18—based on observed improvements in air quality. Under GRAP IV limitations, the governments of Delhi and the NCR are mandated to halt in-person classes for grades VI-IX and class XI. However, entry into Delhi for all LNG, CNG, electric, and BS-VI diesel trucks remains permitted.
Additionally, the India Meteorological Department (IMD) reported a minimum temperature of 5.4 degrees Celsius in Aya Nagar, which is 3 degrees Celsius below normal, with humidity levels at 93 percent as of 8:30 a.m. The maximum temperature is expected to reach approximately 22 degrees Celsius, with a minimum of 5 degrees Celsius on Wednesday, according to the latest IMD bulletin.