Context:

As Delhi-NCR grapples with deteriorating air quality, the Commission for Air Quality Management (CAQM) has implemented Stage 4 restrictions under the Graded Response Action Plan (GRAP), following a sharp rise in the region’s Air Quality Index (AQI).

About Stage 4 Measures:

In response to the alarming rise in pollution levels, several immediate measures have been enforced under GRAP Stage 4. These include:

1.    Hybrid Learning for Schools: Schools are mandated to adopt hybrid classrooms, where online and offline learning modes are combined, in an effort to limit students' exposure to hazardous outdoor air. This will apply to all schools except classes 10 and 12, as these students prepare for exams.

2.    Construction Halt: All construction activities, which contribute significantly to particulate matter, have been suspended.

3.    Truck Bans and No-Truck Zones: Diesel-run trucks, particularly those that are BS-IV and older, are prohibited from entering Delhi, unless they are involved in essential services. Additionally, non-essential vehicular movement is being restricted, with no-truck zones in effect to reduce emissions.

The decision to invoke Stage 4 comes after forecasts by the India Meteorological Department (IMD) and the Indian Institute of Tropical Meteorology (IITM) warned of further deterioration in air quality, with AQI likely to breach 400 in the coming days. This could push the region into the "Severe" or even "Severe Plus" category.

Causes and Impact of the Pollution Surge

·        The drastic decline in air quality has been attributed to a combination of factors: calm winds, low temperatures, and dense fog, which trap pollutants close to the ground.

·        Local pollution sources, including vehicular emissions, stubble burning, and the recent use of firecrackers during festivities, have further exacerbated the problem.

·        Authorities have also urged residents to minimize outdoor activities and adopt sustainable practices to help reduce exposure and mitigate the pollution levels.

About GRAP:

The Graded Response Action Plan (GRAP) is a set of emergency measures designed to mitigate air pollution in the Delhi-NCR region when the air quality reaches critical levels.

·        It is activated to prevent further deterioration of air quality and protect public health.

·        GRAP was approved by the Supreme Court in 2016 following the case of M.C. Mehta vs. Union of India and was officially notified in 2017.

Stages of GRAP

The GRAP has four stages, each triggered by a specific range of the Air Quality Index (AQI). The stages and their measures are:

• Stage I (Poor AQI - 201-300): Enforce NGT and Supreme Court orders on over-aged vehicles.
• Stage II (Very Poor AQI - 301-400): Actions at hotspots and regulation of Diesel Generators.
• Stage III (Severe AQI - 401-450): Restrictions on BS-III petrol and BS-IV diesel vehicles; potential school suspensions for younger children.
• Stage IV (Severe Plus AQI - >450): Ban on non-electric, non-CNG, non-BS-VI diesel vehicles and restrictions on vehicle entry from outside Delhi.