Hazardous levels of PM2.5 were limited to northern provinces on Wednesday morning, with with the worst air pollution still in Chiang Rai’s Mae Sai district, according to the Pollution Control Department.
The department reported at 10am on Wednesday that unsafe levels of particulate matter 2.5 micrometres and less in diameter (PM2.5) ranged from 58 to 320 microgrammes per cubic metre of air over the past 24 hours.
The lowest level was in Muang district of Phrae and the worst pollution was still in Mae Sai district of Chiang Rai. The government-set safe threshold is 50μg/m³.
Pinsak Suraswadi,…
