Dense Fog Blankets Delhi-NCR Again, AQI Drops To 'Severe' At 408, Flights, Trains Schedule Disrupted

The Delhi International Airport Limited (DIAL), in update issued around 6 a.m. on Friday, said the flight departures have been "impacted" due to dense fog.

New Delhi:Normal life is thrown out of gear in Delhi-National Capital Region (NCR) on Friday after dense fog enveloped the region, reducing visibility to zero and severely affecting flight and train operations. The India Meteorological Department (IMD) has issued a moderate to very dense fog warning for many parts of North India, including Punjab, Haryana and Rajasthan.

The capital's air quality index (AQI) was recorded at 408 around 6 a.m., dropping to the 'severe' category from 'very poor', according to the data on the Central Pollution Control Board website. The Delhi International Airport Limited (DIAL), in an update issued around 6 a.m. on Friday, said the flight departures have been "impacted" due to dense fog.

Aviation website Flightradar24 said flight delays averaged 41 minutes. The DIAL, however, reassured travellers that CAT III-compliant flights can land and depart from the airport. In the past few weeks, thick fog in North India has cancelled or delayed hundreds of flights and trains.

An AQI between zero and 50 is considered 'good', 51 and 100 'satisfactory', 101 and 200 'moderate', 201 and 300 'poor', 301 and 400 'very poor', and 401 and 500 'severe'. According to the IMD, Delhi's minimum temperature was 9.6 degrees Celsius.

The weather agency said the capital's maximum and minimum temperatures would hover between 6 and 20 degrees Celsius on Friday. The Centre's panel on Delhi-NCR's air quality on Thursday re-implemented stage 3 curbs under the Graded Response Action Plan (GRAP) amid a sharp rise in air pollution levels owing to unfavourable meteorological conditions.

Delhi's air pollution levels showed an increasing trend with the 24-hour average air quality index (AQI) clocking 357 at 4 pm on Thursday, up from 297 on Wednesday.

The Commission for Air Quality Management, responsible for strategising air pollution mitigation in Delhi-NCR, directed authorities in the region to immediately implement curbs prescribed under GRAP Stage 3 to prevent the situation from worsening further. GRAP Stage 3, revoked on Sunday, entails a ban on non-essential construction work.

Classes up to grade 5 are required to shift to hybrid mode under Stage 3. Parents and students have the option to choose online education wherever available. Under Stage 3, BS-III petrol and BS-IV diesel cars (4-wheelers) are restricted in Delhi and nearby NCR districts.

Persons with disabilities are exempt. Stage 3 also bans non-essential diesel-operated medium goods vehicles with BS-IV or older standards in the national capital.

During winters, the Delhi-NCR region enforces restrictions under GRAP, which categorises air quality into 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).