Delhi's air quality showed 'unusual improvement' due to increased wind speed, favourable for dispersion of pollutants, even as it remained in the 'poor' category on Sunday, authorities said. The overall air quality index (AQI) was recorded at 262 which falls in the 'poor' category, according to the apex pollution body Central Pollution Control Board.
Air quality in three areas in the national capital were recorded as 'very poor' while 21 areas recorded 'poor' air quality, according to data from the CPCB. The level of PM2.5 (particles in the air with a diameter of less than 2.5 micrometres) was recorded at 111 and the PM10 level was recorded at 241, it said.
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'.
Meanwhile, according to Centre-run Centre-run System of Air Quality and Weather Forecasting (SAFAR), the improvement in air quality is unusual for this time of the year."The major role is being played by late-night faster wind speed. However, the air quality is expected to keep oscillating between poor and very poor for the next three days," SAFAR said. The city's air quality has been swinging between very poor and poor for the past one week. Residents have been waking up to misty and hazy morning, with sky covered in blanket of toxic air. The Supreme Court appointed Environment Pollution (Prevention and Control) Authority brought in series of measures to ease pollution woes Delhi has been reeling under. It placed ban on construction activity in areas that recorded severely low pollution levels. Trucks and other commercial vehicles headed to Delhi were also denied entry in the capital two weeks ago to prevent increase in pollution level.