KATHMANDU, May 24: The air quality in the capital city which did not see any improvement until the third week of prohibitory order has finally improved in the last few days. Rain and strong winds have scattered the pollution concentrated in the valley.
Experts believe that the prohibition period has also contributed to reducing emissions from vehicles which is considered to be the main cause of pollution in Kathmandu Valley.
The air quality measurement station at Ratna Park has shown that the particulate matter (PM 2.5), which is considered to be responsible for air pollution, has been below the national standard for the last three days.
Nepal, in measuring air pollution, has defined clean air as an average of 40 μg/m³ (micrograms of fine particles per cubic meter) of air per day. At 10:00 PM on Wednesday at Ratna Park, the level of PM 2.5 had risen to 71 points, but since then it has been steadily declining. The level of PM 2.5 was less than 10 points in Ratna Park at 3:00 PM on Sunday.
In recent days, not only in the valley, but also in other parts of the country, the level of air pollution has improved significantly. The pollution measurement stations set up by the Department of Environment under the Ministry of Forests and Environment in Dang, Lumbini, Hetauda, Bharatpur, Pokhara, Simara, Janakpur, Biratnagar and Dhankuta, among other places, have also shown that the PM 2.5 level is within the national standard and is not harmful to public health.
Barun Poudel, a meteorologist at the Department of Hydrology and Meteorology, said that a storm in the Arabian Sea a few days ago caused rain from the west to the east of Nepal which eventually contributed to scattering the pollution. He added that the air quality will improve further as the monsoon is expected to start in the next three weeks.