
Red-coded hazardous smog levels again recorded in 13 areas in the upper North, with the worst pollution in Pai district of Mae Hong Son, the Pollution Control Department reported on Monday.
The department reported the unsafe levels of particulate matter 2.5 micrometres and less in diameter (PM2.5) in Chiang Mai, Chiang Rai, Lamphun, Mae Hong Son and Nan provinces.