New Delhi, Dec 20 (IANS) Delhi-NCR woke up to a thick blanket of fog on Saturday, with the India Meteorological Department issuing an orange alert for dense fog conditions expected to persist through the day.

“Partly cloudy sky. Dense to very dense fog during morning hours. Mist/shallow fog during night/early hours,” the IMD said in its forecast for the national capital.

The weather department explained that “very dense fog” is recorded when visibility drops to between 0 and 50 metres, while visibility of 51 to 200 metres is categorised as “dense”.

Visibility between 201 and 500 metres falls under the category of “moderate” fog, and visibility between 501 and 1,000 metres is termed “shallow” fog.

Alongside the poor visibility, Delhi continued to grapple with severe air pollution. The Air Quality Index remained in the “very poor” category at 376 as of 6:00 a.m., according to data from the Central Pollution Control Board.

The Air Quality Early Warning System has forecast that pollution levels are likely to worsen further, with the AQI expected to enter the 400-plus “severe” category over the weekend.

Several areas across the city recorded alarmingly high pollution levels. According to the CPCB, the AQI at Sarai Kale Khan stood at 428, while Akshardham registered 420.

Rao Tularam Marg recorded an AQI of 403, and the Barapullah flyover area logged a reading of 380.

Other major pollution hotspots included Anand Vihar with an AQI of 428, Ashok Vihar at 407, and the ITO area at 429, placing large parts of the national capital firmly in the ‘severe’ air quality category.

Amid the worsening situation, the Commission for Air Quality Management has invoked all measures under Stage IV of the Graded Response Action Plan across Delhi-NCR.

GRAP Stage IV restrictions include a ban on non-essential construction activities, restrictions on the entry of certain diesel vehicles, and intensified enforcement to curb pollution sources.

As per AQI standards, air quality is classified as ‘good’ between 0 and 50, ‘satisfactory’ from 51 to 100, ‘moderate’ between 101 and 200, ‘poor’ from 201 to 300, ‘very poor’ between 301 and 400, and ‘severe’ when it reaches 401 to 500.

–IANS

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