Delhi's air quality was recorded in the 'very poor' category due to a drop in wind speed and mild shower that enhanced the pollutant holding capacity of air and worsened the pollution in the national capital, authorities said Friday.
According to the Central Pollution Control Board (CPCB) data, the overall air quality index (AQI) of the city was at 322, which falls in the 'very poor' category.
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'.
The CPCB said 29 areas recorded 'very poor' air quality while seven areas recorded poor air quality.
The level of PM2.5 (particles in the air with a diameter of less than 2.5 micrometres) was recorded at 165 and the PM10 level 258, it said.
In the National Capital Region, Ghaziabad recorded 'very poor' air quality while Gurgaon, Greater Noida and Noida recorded 'poor' air quality, the CPCB data showed.
According to the Centre-run System of Air Quality and Weather Forecasting (SAFAR), the overall air quality deteriorated over Delhi to very 'poor' category.
"Very little traces of shower in the morning may deteriorate the air quality by introducing lot of moisture instead of washing away," the SAFAR said.
"Gentle fog is now mainly confined to early morning hours. Although there is no further appreciable drop in temperature but persistence cool conditions still not allowing boundary layer to lift up. The AQI will remain in lower to middle range of very poor during the next three days," the SAFAR said.
