His Majesty the King of Thailand is worried about the haze in the North and has instructed the president of the Rajaprajanigroh Foundation to visit affected areas, a senior official said yesterday.

The Pollution Control Department yesterday reported that atmospheric levels of fine-particle dust, or PM 10, were unsafe in all nine upper northern provinces.

Officials in Chiang Rai’s Mae Sai district prepared to evacuate residents of tall buildings as PM10 reached a dangerous level of 357 micrograms per cubic metre (mg/m3) – way above the “safe” level of 120 mg/m3.

Read more: The Nation