GRAP Stage 4 imposed in Delhi as AQI hits ‘severe’: What's open, what's closed?

The government's Commission for Air Quality Management (CAQM) has imposed the strictest GRAP Stage 4 curbs in Delhi-NCR , late on December 16, according to a PTI report.

Curbs under the Graded Response Action Plan's (GRAP) Stage 4 plan, include a ban on all construction activities, a ban on the entry of polluting trucks carrying non-essential goods into Delhi, and mandatory shifting of school to hybrid mode, with the exceptions being classes X and XII, it added.

Why GRAP Stage 4?

Delhi's 24-hour average Air Quality Index (AQI), which was 379 at 4 pm on December 16 and breached the 400 mark around 10 pm.

The weather conditions saw extremely calm wind and buildup of an inversion layer, which adversely affects the vertical mixing height — the height up to which pollutants can disperse. Thus, a decision to impose very restrictive measures under Stage 4 came just hours after the CAQM implemented Stage 3 in the afternoon, as per the report.

What's Open and What is Closed?

• Mandatory hybrid classes for students in grades VI-IX and XI in Delhi, Gurugram, Faridabad, Ghaziabad and Gautam Buddh Nagar. Hybrid means the schools will have a mix a physical and online classes for all students except those in Class X and XII.
• Classes up to grade V were also shifted to hybrid mode under Stage 3 where parents and students can choose online education wherever available.
• Ban on all construction and demolition activities, including public projects such as flyovers, highways, pipelines, and power lines.
• Non-essential diesel trucks are prohibited from entering Delhi.
• Public, municipal, and private offices must decide on allowing only 50 per cent of staff to work in offices, with the remaining staff working from home.
• States may consider additional measures such as closing colleges, non-essential businesses and implementing odd-even vehicle restrictions.
• Under Stage 3, use of BS-III petrol and BS-IV diesel cars (4-wheelers) is restricted in Delhi and nearby NCR districts. Except for people with disabilities.
• The Delhi and NCR state governments must stagger timings for public and municipal offices under Stage 3. The Centre may also consider this for its offices in Delhi-NCR.

GRAP Stage 4 Re-imposed Amid Weather and Pollution Conditions

The national capital imposes curbs under GRAP during winters depending on the AQI, according to the report. The CAQM categorizes these measures in four stages — Stage I (Poor, AQI 201-300), Stage II (Very Poor, AQI 301-400), Stage III (Severe, AQI 401-450), and Stage IV (Severe Plus, AQI above 450).

GRAP 4 was first imposed in Delhi this year in November due to consistently high pollution levels in the city and adjoining areas. The Supreme Court allowed the CAQM to relax the curbs in the first week of December after the city's air quality improved, it added.

Unfavourable meteorological conditions combined with vehicle emissions, paddy-straw burning, firecrackers and other local pollution sources lead to hazardous air quality levels in Delhi-NCR during winters. Doctors say that breathing Delhi's polluted air is equivalent to smoking approximately 10 cigarettes a day.

Prolonged exposure to high pollution levels can exacerbate respiratory issues such as asthma, bronchitis and chronic obstructive pulmonary disease (COPD) and significantly increase the risk of cardiovascular diseases, according to doctors.

(With inputs from PTI)