Sunday morning, the northern province of Chiang Mai was blanketed with a thick haze, with a pollution level over 20 times higher than the World Health Organization (WHO) considers safe.
Residents in the city said the haze, apparently worsened by wildfires, was so thick that it blocked the view of the Doi Suthep. At 8am on Sunday, the province was ranked as the city with the second-worst air pollution in the world.
According to https://www.iqair.com/th/thailand/chiang-mai, the concentration of PM2.5 ultra-fine dust was at a red level, 22.2 times what the WHO considered safe.
Based on information from cmuccdc.org of Chiang Mai University, the highest reading during the preceding 24 hours was recorded at Ban Arunothai Hospital in Chiang Dao district at 460 microgrammes per cubic metre (μg/m³).
Nearby areas also registered between 300-400 μg/m³. Ban Hua To recorded 454 μg/m³ while the Chiang Dao wildlife sanctuary office saw 374 μg/m³.
Chiang Mai's provincial administrative centre for tackling wildfires and haze on Sunday reported a total of 90 hotspots in 17 districts.
Of these hotspots, 16 were found in Chiang Dao district, 11 in Hot, 10 each in Omkoi and Mae Chaem, eight in Mae Taeng, six in Fang, five each in Samoeng, Chai Prakan and Mae Wang, four in Doi Tao, two each in Mae Rim, Phrao and Wiang Haeng, and one each in Galyani Vadhana, Mae On, Mae Ai and Chom Thong.
According to Thailand’s Geo-Informatics and Space Technology Development Agency (Gistda), 11 northern provinces had very unsafe levels of PM2.5 ultra fine dust hoovering between 77.8 μg/m³ and 204.1 μg/m³. Among them, Mae Hong Son (highest), Chiang Mai, Chiang Rai, Uttaradit and Sukhothai (lowest).
Unsafe (orange) levels of ultra-fine dust were also reported in 19 other provinces in the northern and northeastern region. People were advised to wear facemasks while outside.
According to Maharat Nakhon Chiang Mai Hospital, the number of people seeking treatment for respiratory symptoms exceeds 30,000 this year.
The Thai Meteorological Department (TMD) warned on Sunday the haze situation in the north remains critical as the number of hotspots is unchanged.
Large crowds turned out on Saturday at an exhibition organised by Chiang Mai University's Faculty of Medicine to raise awareness of pollution. The event, held at Central Plaza in Chiang Mai Airport, also marked the faculty's 65th anniversary.