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.
Over the past 24 hours as of noon on Monday they ranged from 95μg/m³ per cubic metre of air in Hot district of Chiang Mai to 255 in Mae Hong Son's Pai district.
Elsewhere the levels were 103μg/m³ in tambon Suthep of Muang district of Chiang Mai, 104 in Li district of Lamphun, 109 in tambon Chang Phueak of Chiang Mai's Muang district, 111 in tambon Sri Phum of Chiang Mai's Muang district, 112 in Mae Chaem district of Chiang Mai and Chalerm Prakiat district of Nan, 114 in Muang district of Mae Hong Son, 116 in Chiang Khong district of Chiang Rai, 122 in Muang district of Chiang Rai, 154 in Mae Sai district of Chiang Rai and 166 in Chiang Dao district of Chiang Mai.
Pinsak Suraswadi, director-general of the Pollution Control Department, said the severe air pollution continued because of hotspots in neighbouring countries, forest fires and stagnant air.
He expected the current conditions to continue in the upper North until next Monday, especially in Chiang Rai and Nan provinces.
Toxic haze limits visibility of the Doi Suthep mountain range in Muang district of Chiang Mai on Monday. (Photo: Dave Kendall)