The overall air quality in the national Capital was in the 'very poor' category on Tuesday, while some areas in the city experienced 'severe' pollution due to low wind speed, which is unfavourable for dispersion of pollutants, authorities said.

According to the Central Pollution Control Board (CPCB) data, the overall air quality index in the city was recorded at 372, which falls in the 'very poor' category.

Ashok Vihar, Anand Vihar, Bawana, Mundaka, Rohini, Sonia Vihar and Wazirpur, all recorded 'severe' air quality while 21 areas recorded 'very poor' air quality, it said.

At 396, the overall air quality of Ghaziabad was the worst in the National Capital Region (NCR), just points below severe category. Gurgaon, Faridabad, Noida and Greater Noida too recorded 'very poor' overall air quality.

On Tuesday, the PM2.5 particles in the air with a diameter of less than 2.5 micrometres level was recorded at 220, while the PM10 level was recorded at 369, the CPCB data said. According to the Centre-run System of Air Quality and Weather Forecasting (SAFAR), air quality in the national capital is expected to remain in the 'very poor' category for the next two to three days.

"At present, winds are unfavourable for dispersion but it may increase slightly to favour dispersion. Humidity is still high which is unfavourable. Fire counts from stubble burning declined and will have marginal impact," the SAFAR said in a report.

Authorities are mulling to use to artificial rain to clear the toxic air but cloud seeding would require certain meteorological conditions which are currently not favourable.

A senior official said, "For artificial rain, we need clouds and currently the meteorological conditions are not favourable for inducing an artificial rain."

He also said the method of artificial rain is used only in severe-plus emergency situation.