Delhi-NCR Enforces GRAP-4 Restrictions as Air Quality Deteriorates to 'Severe+' Category

The Centre’s air quality panel, the Commission for Air Quality Management (CAQM), invoked Stage IV of the Graded Response Action Plan (GRAP) in Delhi-NCR on Monday night as air quality dipped to the "Severe+" category. The decision came after Delhi's 24-hour average Air Quality Index (AQI) breached the 400 mark at 10 PM, with unfavourable meteorological conditions trapping pollutants near the surface.

AQI Breach and Emergency Measures

Delhi’s AQI, which stood at 379 at 4 PM, saw a sharp rise due to calm winds and the buildup of an inversion layer that lowered the vertical mixing height—the zone above the ground where pollutants can disperse. The lack of wind and a temperature drop compounded the pollution crisis.

In a late-night emergency meeting, CAQM decided to implement the strictest GRAP-4 measures. The panel cited "highly unfavourable meteorological conditions" and "absolute calm wind conditions" as the primary reasons for the deteriorating air quality.

Restrictions Under GRAP-4

GRAP-4 is the most stringent set of anti-pollution measures aimed at reducing emissions and protecting public health. The restrictions include:

• Construction Ban: All construction and demolition activities, including public infrastructure projects such as highways and flyovers, have been halted.
• Truck Restrictions: Entry of trucks carrying non-essential goods into Delhi has been banned, except for LNG, CNG, electric, and BS-VI diesel trucks.
• School Adjustments: Schools in Delhi-NCR will shift to a hybrid mode of education for students up to Class IX and XI, combining online and physical classes where feasible.
• Vehicle Restrictions: Ban on BS-III petrol and BS-IV diesel vehicles in Delhi, Gurugram, Faridabad, Ghaziabad, and Noida. Exceptions are made for vehicles modified for use by persons with disabilities.
• Emergency Measures: State governments have been advised to consider closing non-emergency commercial activities, implementing odd-even vehicle rules, and allowing only 50% of office staff while the rest work from home.

Impact on Public Life

The stringent measures aim to curb immediate emissions and protect vulnerable groups, including children, the elderly, and individuals with respiratory ailments. Officials have also recommended limiting outdoor activities and wearing masks for those stepping out.

In addition to the GRAP-4 restrictions, the New Delhi Municipal Council (NDMC) has announced the installation of "mist sprayers" on electric poles along Lodhi Road to combat air pollution. These sprayers use treated water to disperse the fine mist, aiming to settle the particulate matter.

Weather and Cold Wave Conditions

Delhi recorded a minimum temperature of 4.5°C on Monday, 4.1°C below normal, marking the fourth time in December that temperatures dropped below 5°C. The India Meteorological Department (IMD) has forecast a maximum temperature of 24°C and a minimum of 5°C on Tuesday, with cold wave conditions expected to persist.

Supreme Court Directions and Revised GRAP Norms

The Supreme Court had earlier revised the GRAP thresholds, mandating the imposition of Stage IV when AQI crosses 400, down from the earlier threshold of 450. This revision aims to ensure a faster response to deteriorating air quality.

Public Advisory

Authorities have issued a series of health and safety advisories:

• Avoid outdoor activities, especially for vulnerable groups.
• Use public transport or carpool to reduce emissions.
• Refrain from burning wood or coal for heating.
• Employers are encouraged to allow remote work where possible.

Looking Ahead

This is the second time this winter that GRAP-4 restrictions have been implemented. Authorities are monitoring the air quality and meteorological conditions closely to decide on lifting or extending the restrictions.

Delhi-NCR’s recurring pollution crisis highlights the urgent need for long-term solutions, including reducing industrial emissions, promoting green energy, and improving public transport infrastructure. For now, these immediate measures aim to provide relief during a critical period of severe air pollution.