Air quality in Delhi on Saturday was the best in over a month as drizzle coupled with bright sun and wind helped disperse particulates, an official said.
The Air Quality Index, at 298, was classified as 'poor' by the Central Pollution Control Board (CPCB). It was an improvement over 'very poor' recorded over the last few days.
The System of Air Quality and Weather Forecasting and Research (SAFAR) monitors recorded 24-hour average of Particulate Matter (PM) 2.5 and PM 10 at 128 and 199 micrograms per cubic metre respectively.
The corresponding prescribed standards are 60 and 100. 'Poor' quality air might trigger breathing discomfort to most people on prolonged exposure, the CPCB says.
However, it is a major improvement over what Delhi underwent over the last two weeks when pollution had hit emergency levels and a thick blanket of smog had descended over the region.
"More rains would have helped. But we certainly expect rapid clean up of the air over the next few days as wind movement will further pick up. Air channels have opened due to the weakening of a depression over Bay of Bengal," CPCB's air lab chief Dipankar Saha said.
The last time the AQI was recorded below 300 was on October 16.
Authorities in Delhi have lifted certain stringent steps such as ban on entry of trucks and construction activities in light of the improvement.
Saha said that light rains experienced at many parts of the city aided in the clean up process, which began a few days ago as pollutants from external sources such as stubble burning stopped entering due to a change in wind direction.
However, the SAFAR, which comes under the Ministry of Earth Sciences, had forecast that there may be a renewed spike in pollution levels due to rise in moisture which traps pollutants.
A 'very poor' AQI comes with the warning that people may develop respiratory illness on prolonged exposure while exposure to 'severe' air affects healthy people and seriously impacts those with existing respiratory or cardiovascular diseases.