Red alert: PM2.5 readings in Chiang Mai hit hazardous levels

SUNDAY, MARCH 12, 2023

Air pollution in Chiang Mai hit critical levels on Sunday morning with PM2.5 readings going well beyond 100 micrograms per cubic metre of air (µg/m³) in many areas.

All air-quality measurement stations in the province reported red alert on Sunday morning with the highest PM2.5 pollution detected in Chiang Dao district’s Tambon Muang Na with a reading of 145µg/m³.

PM2.5 stands for particles of fine dust that are 2.5 micrometres in diameter (more than 100 times thinner than human hair) that remain suspended in the air for long periods. These particles are particularly dangerous for people with chronic respiratory and heart disease.

Thailand has set the safe level of PM2.5 pollution at 50µg/m³, though the World Health Organisation sets it at 12µg/m³ or less.

The PM2.5 readings in Chiang Mai on Sunday morning were:

• Tambon Chang Puak, Muang district: 109µg/m³

• Tambon Sriphume, Muang district: 97µg/m³

• Tambon Hang Dong, Hot district: 129µ/m³

• Tambon Muang Na, Chiang Dao district: 145µg/m³

• Tambon Suthep, Muang district: 108µg/m³

Vendors at many fresh markets complained that their sales dropped by more than half because many people decided to stay indoors due to the pollution.

Dr Pannawit Chantharaklang from Nakhonping Hospital said people should stay in air-conditioned rooms and use air-purifying machines if they have any.

Chiang Mai governor Nirat Pongsitthavorn, meanwhile, said he has instructed all relevant agencies to try their best to prevent forest fires, which are believed to be the main source of pollution.

If a forest fire is spotted, it should be extinguished within a day, he said, adding that helicopters are on standby to join fire-fighting operations.

The local offices of the Royal Rainmaking and the Agricultural Aviation Department have been advised to go on alert to create artificial rain once there is enough humidity in the air.