Air quality index (AQI) dropping to the “severe-plus” category
New Delhi: A dense layer of smog, comprising a hazardous mixture of smoke and fog, blanketed the Delhi-National Capital Region (NCR) this morning, resulting in the air quality index (AQI) dropping to the “severe-plus” category. This alarming situation prompted authorities to implement more stringent pollution control measures. The smog also significantly reduced visibility in the national capital, leading various airlines to indicate potential delays in flight operations. At 7 am, visibility at Palam was recorded at just 150 meters.
Real-time data from the System of Air Quality and Weather Forecasting and Research (SAFAR) indicated that the AQI in Delhi reached 481 at 6 am, marking the most severe level observed this season. Officials attributed this deterioration to “unfavorable” meteorological conditions affecting the Delhi-NCR region.
The AQI classifications are as follows: 0 to 50 is deemed good, 51 to 100 satisfactory, 101 to 200 moderate, 201 to 300 poor, 301 to 400 very poor, 401 to 450 severe, and above 450 severe-plus.
In response to the deteriorating air quality, the Centre’s air quality panel has activated stricter pollution control measures for the Delhi-NCR under Stage 4 of the Graded Response Action Plan (GRAP), effective from 8 am today. This action supplements the preventive measures already in place under Stages 1, 2, and 3 of the GRAP.
The GRAP framework for Delhi-NCR consists of four stages based on air quality levels: Stage 1 for “poor” air quality (AQI 201-300), Stage 2 for “very poor” air quality (AQI 301-400), Stage 3 for “severe” air quality (AQI 401-450), and Stage 4 for “severe-plus” air quality (AQI above 450).
The Commission for Air Quality Management (CAQM) has advised the public, especially vulnerable groups such as children, senior citizens, and individuals with respiratory, cardiovascular, cerebrovascular, or other chronic health conditions, to remain indoors.
GRAP 4 In Delhi As Air Quality Worsens
Under Grap 4, entry into Delhi will be restricted for trucks, allowing only those transporting essential goods or utilizing clean fuels such as LNG, CNG, BS-VI diesel, or electric power. Light commercial vehicles not registered in Delhi will be banned unless they are electric vehicles or powered by CNG or BS-VI diesel, as well as those carrying essential items.
Delhi-registered medium and heavy goods vehicles that are BS-IV or older diesel models are prohibited, with the exception of those engaged in essential services.
In-person classes have been halted for all students except those in grades 10 and 12. All construction activities, including those related to highways, roads, flyovers, power lines, pipelines, and other public projects, have been suspended.
Public and private offices in the Delhi-NCR region are advised to operate at 50 percent capacity, with the remainder of employees working from home. Central government employees may also be offered work-from-home arrangements.
State governments may take further actions, such as closing colleges, restricting non-essential commercial activities, and enforcing odd-even vehicle regulations.
This year, approximately 38% of the pollution in the national capital has been attributed to stubble burning or farm fires in the adjacent states of Punjab and Haryana. Delhi faces significant smog issues each winter as cold air traps dust, emissions, and smoke from illegal agricultural burning.
