Bangkok air slowly clearing

A teacher demonstrates how to wear a face mask to protect against hazardous dust particles, at Songvithaya School in Samut Prakan province on Wednesday. (Photo by Somchai Poomlard)

Wind reduced smog levels in greater Bangkok on Wednesday with hazardous dust levels ranging between 37 and 69 microgrammes per cubic metre of air over the past 24 hours and fewer unsafe zones.

The Pollution Control Department reported the better conditions and expected more wind on Thursday, based on forecasts by the Meteorological Department.

In Bangkok, hazardous levels of particulates 2.5 micrometres or less in diameter (PM2.5) were reported on Kanchanaphisek Road in Bang Khunthian district, Din Daeng Road in Din Daeng district and in Phlab Phla sub-district of Wang Thongland district.

Unsafe dust concentrations were also detected in tambon Nakhon Pathom of Muang district in Nakhon Pathom province, tambon Song Khanong of Phra Pradaeng district in Samut Prakan province, and tambon Om Noi of Krathum Baen district and on Rama II Road in Muang district of Samut Sakhon province.

Roong Aroon School in Bang Khunthian district on Wednesday closed classes from the level of kindergarten to Prathom 3 until the weekend, in the interests of the pupils' health.

The safe PM2.5 threshold in Thailand is set at 50mcg.

Screenshot from http://aqicn.org/city/bangkok/

According to the website aqicn.org, Bangkok's air quality was still 'unhealthy' at noon on Wednesday. The site forecast a significant drop in airborne particulate matter by the weekend.

Screenshot from http://aqicn.org/city/bangkok/

Video report from Tuesday: