The March 2003 indictment by the Supreme Court of Nepal and unrelenting public pressure have finally forced the country's government to formulate a National Ambient Air Quality Standard (naaqs). The same has been sent to the law ministry for publication.

In recent years, high levels of air pollution have emerged as Nepal's most visible component of environmental degradation. It is estimated that air pollution costs the country about US $4 million per year in medical costs for Kathmandu residents. The Kathmandu Valley's bowl-like topography and low wind speeds during winter create poor dispersion conditions. These factors expose the area to severe air pollution. A Nepalese daily has reported that the current level of particulate matter (PM10) in the Putalisadak locality is as high as 385 microgrammes per cubic metre. Significantly, this is three times the air quality norms the government has now set for PM10.

naaqs sets the permissible limit for six pollutants