Pollutants-laden wind blowing from the North West direction had offset gains from fewer cars, experts said.
The odd-even car-rationing scheme today returned to Delhi for its second phase amid poor air quality in various areas of the city with the real-time readings of gaseous pollutants such as ozone observed on the higher side.
An official in the India Meteorological Department or IMD department said air quality has been moderate over the last 20 days although it dipped today owing to pollutants-laden wind blowing from the North West direction.
The real-time readings of SAFAR (System of Air Quality and Weather Forecasting and Research), Delhi Pollution Control Committee (DPCC) and Central Pollution Control Board (CPCB) stations had PM 10 (coarser than PM 2.5) as the prominent pollutant.
At RK Puram and Punjabi Bagh, Ozone was recorded at 200.3 and 174.5 micrograms per cubic metre respectively around 4 pm. The one hour notified average safe limit for Ozone is 180 micrograms per cubic metre.
"Gasesous pollutants may be on the higher side when seen in real-time basis but on the average they stay well within the prescribed limits except carbon dioxide which goes up at times," the official said.
The effect of the car-rationing scheme would be clear after a week at least after comparison of data as there are less cars on the city's roads due to an extended weekend, the official said.