Chiang Mai announced a five-month ban on open burning from 1 January to 31 May 2026 after PM 2.5 dust levels exceeded standards, affecting health in several areas.
On 2 January 2026, Mr. Ratthaphon Naradisorn, Governor of Chiang Mai Province, signed an official announcement defining the fuel management and burning control zones for fiscal year 2026. The announcement prohibits all types of open burning outside the fuel management zones and bans burning waste, branches, and leaves within community areas. Violators or those who neglect enforcement will face strict legal action in all cases, effective from 1 January to 31 May 2026.
The announcement allows for fuel management in cases of extreme necessity. Such cases must register in the Fire-D/Burn check fuel management system and obtain permission from the district-level Command Center for Forest Fire, Haze, and Dust Control. Controlled burns must include firebreaks and employ methods to prevent fire from spreading to other areas.
Chiang Mai, along with Chiang Rai, Lamphun, and Mae Hong Son provinces, has been declared a pollution control zone by the National Environment Board in 2025 to regulate, reduce, and eliminate pollution from February to May annually. Air pollution in Chiang Mai mainly stems from open burning, agricultural fires, community burning, and vehicle emissions. Over recent years, PM 2.5 levels have repeatedly exceeded standards by multiple times, severely impacting public health.
According to reporters, PM 2.5 levels in Chiang Mai have begun to rise. The Climate Change Information Center at Chiang Mai University reported hourly PM 2.5 concentrations (at 10:00 a.m.) reaching a maximum of 74 micrograms per cubic meter in Si Dong Yen Subdistrict, Chai Prakan District, classified as orange level with health effects. In the city center at Mae Hia Subdistrict, levels were 52 micrograms per cubic meter.