Wildfires in the North and neighbouring countries are causing thick and hazardous smog in some northern provinces.
Fires burning in the North, Myanmar and Laos caused unsafe smog in Chiang Mai, Chiang Rai and Mae Hong Son provinces, Atthapol Charoenchansa, director-general of the Pollution Control Department, said on Thursday.
Air pollution was especially serious in Chiang Rai, where particulate matter 2.5 micrometres and less in diameter (PM2.5) reached 300 microgrammes per cubic metre of air over the past 24 hours. The safe threshold in Thailand is set at 50 μg/m³.
The Geo-Informatics and Space Technology Development Agency reported 5,183 hotspots in Laos, 5,115 in Myanmar, 1,554 in Cambodia, 1,415 in Vietnam and 1,278 in Thailand.
Chiang Mai province saw 264 hotspots ,including 85 in Chiang Dao district. PM2.5 measured 100 μg/m³ in Mae Chaem district of Chiang Mai.