New Delhi, Jan 15 (PTI) The Delhi Directorate of Education (DoE) Wednesday directed all schools to conduct hybrid classes for students up to class 9 and that of class 11 after curbs under stage four of the Graded Response Action Plan were invoked in the city amid a sharp dip in air quality.

Calm winds, low temperatures and foggy conditions allowed the accumulation of pollutants in the region, with the air quality index soaring from 275 on Tuesday to 396 at 6 pm on Wednesday.

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The India Meteorological Department and the Indian Institute of Tropical Meteorology predicted that AQI may breach the 400 mark soon.

Accordingly, the Commission for Air Quality Management (CAQM) directed authorities in Delhi-NCR to "straightway invoke" all actions under stages 3 and 4 with immediate effect.

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In a circular, the DoE stated, "All heads of government, government-aided, unaided private schools under DoE, NDMC, MCD, and the Delhi Cantonment Board are directed to conduct hybrid classes for students up to Class 9 and 11, wherever online learning is feasible, effective immediately until further notice."

Stage 4 curbs include a ban on all construction activities, entry of non-essential polluting trucks into Delhi, and mandatory shifting of school classes, except for classes 10 and 12, to hybrid mode.

Non-essential diesel trucks are prohibited from entering Delhi, while Delhi-registered BS-IV and older diesel-run heavy goods vehicles are banned, except for essential services under Stage 4.

During winters, the Delhi-NCR region enforces restrictions under GRAP, which categorizes air quality into four stages – Stage 1 (Poor, AQI 201-300), Stage 2 (Very Poor, AQI 301-400), Stage 3 (Severe, AQI 401-450), and Stage 4 (Severe Plus, AQI above 450).

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