Delhi-NCR is once again battling hazardous air pollution, with authorities invoking Stage IV of the Graded Response Action Plan (GRAP), the strictest set of anti-pollution measures, after air quality deteriorated sharply over the weekend.

What is GRAP 4 and when is it imposed?

GRAP Stage IV, categorised as “Severe Plus”, is enforced when the Air Quality Index (AQI) crosses 450. On Saturday evening, Delhi’s AQI surged to 448, triggering immediate restrictions across the National Capital Region.

GRAP Stage IV is an emergency response aimed at rapidly cutting emissions and limiting public exposure during extreme pollution. Once activated, it brings sweeping curbs on transport, construction, and workplace operations.

Key restrictions under GRAP IV

  • Entry of all trucks into Delhi is banned, except those carrying essential goods
  • Only CNG, LNG, electric and BS-VI diesel trucks are permitted
  • All non-essential construction and demolition activities are halted
  • State governments may shift classes for Classes 6 to 9 and Class 11 to online mode
  • Public, private and municipal offices may operate at 50% capacity, with the remaining staff working from home
  • The Centre may also extend work-from-home options for central government employees