BANGKOK: Chiang Mai is preparing to tighten controls on toxic PM2.5 pollution.
Siwakorn Buapong, Deputy Governor of Chiang Mai Province, said PM2.5 levels in Mueang Na subdistrict, Chiang Dao District, have risen above 125 micrograms per cubic metre for four consecutive days.
The province is set to consider declaring the area a disaster-stricken zone on March 31, while mobile medical units will be deployed on April 1, 2026.
Siwakorn spoke about the crisis caused by fine particulate matter (PM2.5) in the area on March 30, saying the province is considering declaring a disaster-stricken area and an area eligible for emergency disaster assistance, focusing on the hardest-hit locations at the subdistrict and village levels.
Criteria for declaring a toxic haze disaster area
Under Ministry of Finance regulations, the province can declare a disaster area when the following conditions are met:
PM2.5 levels must exceed 125 micrograms per cubic metre (µg/m³).
The concentration must remain at that level for five consecutive days.
Current situation
Mueang Na sub-district in Chiang Dao District has already recorded critical pollution levels for four consecutive days.
If the situation does not improve by March 31, it will immediately meet the threshold for a disaster declaration.
Areas under watch and relief measures
Although Chiang Dao District is at a critical level, the deputy governor stressed that the situation in Mueang Chiang Mai District has not yet met the criteria.
Any declaration will focus only on clearly affected areas rather than the whole province, to ensure precision in budget management and relief efforts.
Three urgent measures to protect the public
Cell Broadcast alerts: Messages will be sent immediately to residents in “red” areas, advising them to avoid outdoor activities and wear face masks.
Support for vulnerable groups: The provincial public health office and village health volunteers have been instructed to distribute face masks and speed up the establishment of “Dust-Free Rooms” in communities.
Mobile medical units: On April 1, 2026, the province will mobilise mobile medical teams to treat respiratory illnesses and provide advice to people in high-risk areas.
For Chiang Mai residents in areas where the Air Quality Index (AQI) is in the red zone, the advice is as follows:
Wear an N95 mask when going outdoors.
Keep doors and windows tightly closed, and use an air purifier if available.
Watch for unusual symptoms such as coughing, chest tightness or eye irritation. If symptoms do not improve, seek medical attention or contact local village health volunteers. - The Nation/ANN
