Srilanka, Feb. 2 -- Air Quality Index (AQI) levels exceeded 150 (Unhealthy) in several areas in the beginning of this week. However, by January 31, these values dropped to below 50 (Good) in many parts of the country.

Director Environmental Unit of the National Building Research Organisation (NBRO) Sarath Premasiri, said that many South Asian countries are experiencing the smog and it is not just localised to Sri Lanka.

"These days, the wind direction over Sri Lanka is North-Easterly, so the pollutants from that direction are carried over resulting in a drop in air quality across the country. During this time, there are a lot of pollutants released into the atmosphere by our neighbours and it all depends on the wind's direction; it can ...