Lagatar24 Desk
New Delhi: Delhi residents experienced a sharp drop in air quality on Thursday, November 14, as the city recorded a “severe” Air Quality Index (AQI) level once again, following a dense fog blanket that covered the National Capital Region (NCR) and reduced visibility. On Wednesday, Delhi reached its worst AQI of the season, attributed to what the Central Pollution Control Board (CPCB) described as an “unprecedentedly dense” fog and “episodic event.”
AQI Levels and Monitoring
The AQI at Delhi’s Anand Vihar was marked at an alarming 473 (‘severe plus’) early Thursday morning, as reported by the CPCB. Other areas, such as Aya Nagar, Ashok Vihar, and Wazirpur, recorded AQI levels above 400, categorizing them under “severe.” Throughout the day on Wednesday, Delhi’s AQI escalated significantly, with a reading of 418 at 4 pm that worsened to 454 by 9 pm.
GRAP Measures in Effect
Despite the poor air quality, the Commission for Air Quality Management (CAQM) opted not to implement Stage 3 of the Graded Response Action Plan (GRAP), which includes suspension of primary school classes and a halt to all construction activities. Stage 4 of GRAP, which would be triggered if the 24-hour AQI reaches “severe plus,” remains on standby. Currently, GRAP Stage 2, activated on October 22, is in effect, focusing on dust control and vehicular emissions.
Monitoring Situation
In a statement on X, the CAQM indicated that stronger winds might lower pollution levels starting Thursday, potentially bringing Delhi’s AQI back to the “very poor” category. They are expected to review the situation and possibly implement additional GRAP measures if AQI remains at severe levels.
Impacts of Poor Air Quality
The severe AQI has trapped pollutants due to the dense fog, causing a sharp drop in visibility and temperature. On Wednesday, Delhi recorded its first dense fog and the season’s lowest daytime temperature, falling from 32.8°C on Tuesday to 27.8°C.
Across India, Delhi led with the worst AQI, while Bihar’s Hajipur recorded the second-highest at 417. Of Delhi’s 36 monitoring stations, 30 reported air quality within the severe range.
AQI Categories
The AQI scale categorizes air quality as follows:
•0-50: Good
•51-100: Satisfactory
•101-200: Moderate
•201-300: Poor
•301-400: Very Poor
•401-450: Severe
•Above 450: Severe Plus
With the current AQI levels, authorities may consider invoking GRAP Stage 3, which would restrict construction activities and enforce limitations on BS-III petrol and BS-IV diesel light motor vehicles if severe conditions persist.