The 24-hour average concentration of PM2.5 dropped to as low as 86.22 g/m³ on Saturday, before recording a slight increase to 100.76 g/m³ on Sunday. The figures mark a huge improvement in the pollution levels as compared to the past several weeks. While the highest concentration of PM2.5 was 235.89 g/m³ in January, it reached 200.09 g/m³ earlier this month.

Also, the CPCB reported the air quality index (AQI) to be below 50 (good), on Saturday and below 150 (satisfactory) on Sunday. The AQI had crossed the 350 mark (very poor) in the first week of February and hovered above the 200 mark (poor) in January.

Experts said a gradual drop in the pollution levels was observed in the past six days, apparently due to the strike of private cab operators that brought down the number of vehicles plying on city roads. Haryana State Pollution Control Board (HSPCB) officials, on the other hand, said an increase in temperature had helped improve the situation.

"Traffic congestion is known to be the major cause of air pollution. Although most cabs run on CNG, the cab strike helped reduce traffic congestion, which might have brought down the pollution levels," said Niranjan Raje, former member of Environment Pollution Control Authority (EPCA).