The air quality in Delhi deteriorated to ‘very poor’ category on Friday after a brief respite, as the dispersion of pollutants slowed down, said authorities. According to the Centre-run System of Air Quality and Weather Forecasting (SAFAR), the overall air quality index was recorded at 315 which falls in 'very poor' category.
‘Very poor’ air quality was recorded at 16 places, while 22 areas in the national capital recorded ‘poor’ air quality, according to data by the Central Pollution Control Board.
On Friday, the PM2.5 (particles in the air with a diameter of less than 2.5 micrometres) level was recorded at 139, while the PM10 (particles in the air with a diameter of less than 10 micrometres) was recorded at 210 in Delhi.
An AQI between 0 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'.
Significant improvement was seen in Delhi’s air quality in the past two days after the pollutants were washed away by the rain. But as rain subsided, a rise in pollution level was again recorded on Friday, authorities said.
Fire counts observed in past 24 hours over northwest region of India were few (less than 100 counts), said the Indian Institute of Tropical Meteorology.
"The impact of biomass burning in northwest India is not significant over Delhi," it said.
The PM2.5 concentration will improve in the next two days.
"The air quality is likely to improve next two days but remain in 'poor'/'very poor' category in Delhi-NCR. The impact of biomass burning in northwest India is marginal over Delhi," said the Indian Institute of Tropical Meteorology.