The overall air quality index (AQI) in the national capital was recorded at 308, which comes under 'very poor' category, said the Centre-run System of Air Quality and Weather Forecasting (SAFAR). Delhi's air quality is fluctuating between 'poor' and 'very poor' and it is expected to be in the 'very poor' category in the next two days, the SAFAR said in a report.
“Wind speed is quite good for dispersion of pollutants which is keeping pollution in check,” it said, adding “fire counts from stubble burning declined significantly and hence have negligible impact."
Delhi's air quality showed significant improvement on Wednesday and Thursday after rains washed away the pollutants, but the rainfall also led to increased air capacity to hold pollutants, the SAFAR said.
Data by the Central Pollution Control Board (CPCB) showed the overall AQI at a 'poor' 269.
Air quality in six areas of Delhi was recorded as 'very poor', while 26 recorded 'poor' air quality, the data showed.
On Saturday, the PM2.5 — particles in the air with a diameter of less than 2.5 micrometres — level was recorded at 125, while the PM10 level was recorded at 238, according to Central Pollution Control Board data.
Ghaziabad, Faridabad, Noida and Greater Noida all recorded poor air quality while Gurgaon recorded moderate air quality, according to data.
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'.
Delhi's air quality continued to oscillate between 'poor' and 'very poor' categories on Saturday due to increased pollutant holding capacity of air after rainfall, authorities said.