The Air Quality Index (AQI) in Delhi was recorded in the ''severe'' category on Friday as citizens woke up to an extremely foggy morning and poor visibility.
The city's overall air quality was reported at 431 by the System of Air Quality and Weather Forecasting and Research (SAFAR), falling in the ''severe'' category.
According to the Central Pollution Control Board (CPCB), several spots in the city reported AQIs at the higher end of the ''severe'' category including RK Puram (492), Dwarka Sec-8 (497), Ashok Vihar (472), Shadipur (443) and North Campus (448) among many others.
An AQI between 0-50 is marked good, 51-100 is satisfactory, 101- 200 is moderate, 201- 300 is poor, 301-400 is very poor and 401-500 is considered severe.
Biting cold and dense fog prevail across north-Indian states with very low visibility being reported in several parts.
In light of this fog, 14 trains are running late in the Northern Railway region, the Indian Railways informed.
The India Meteorological Department (IMD) reported dense and very dense fog from north Rajasthan, Punjab, Haryana, Chandigarh, Delhi, Uttar Pradesh, Bihar, Sub-Himalayan West Bengal, Assam and Tripura at 5:30 am in the morning.
Visibility was very poor in the morning with Ganganagar, Patiala, Ambala, Bareilly, Bahraich, Lucknow, Gorakhpur and Baghdogra reporting 25 meters of visibility.
Amritsar, Chandigarh, Agra, Sultanpur, Prayagraj, Varanasi, Patna, Bhagalpur and Tezpur reported 50 meters of visibility while Chandigarh, Hissar, Delhi, Gaya, Dibrugarh and Kailashahar reported 200 meters.
The overall air quality index (AQI) also worsened from yesterday at 431, (severe), the System of Air Quality and Weather Forecasting and Research said.
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