NEW DELHI — Delhi's air quality oscillated between very poor and severe categories on Sunday as pollutants released in the atmosphere due to bursting of firecrackers got trapped due to slow surface winds, authorities said.
The overall air quality index was recorded at 397, which falls in the very poor category, according to the Central Pollution Control Board data.
The Centre-run System of Air Quality and Weather Forecasting (SAFAR) recorded the AQI at 419, which falls in the severe category.
On Sunday, the PM2.5 (particles in the air with a diameter of less than 2.5 micrometres) level was recorded at 271, while the PM10 level was recorded at 440 in Delhi, according to CPCB.
Seventeen areas in Delhi recorded severe air quality while 18 recorded very poor air quality, according to CPCB.
Ghaziabad, Faridabad and Greater Noida and Noida recorded severe air quality while Gurgaon recorded very poor air quality, according to CPCB.
An AQI between 301 and 400 is "very poor", and 401 and 500 is "severe".
Satellite images by SAFAR showed moderate stubble burning fire count that is contributing to 13% pollution in Delhi.
SAFAR said the AQI is fluctuating between very poor to severe categories as a significant amount of local emissions, smoke from firecrackers, was added on Wednesday and Thursday, and it could not flush out due to slow wind speeds.
SAFAR has predicted the air quality would "significantly improve" by Monday.