CHIANG RAI, March 15 – The thick atmospheric haze blanketing Thailand’s northernmost province of Chiang Rai reached a critical level Monday, particularly in Mae Sai district, which went over the top, registering over 400 microgrammes per cubic metre.

The level of 431.6 microgrammes per cubic metre, which exceeded a safety standard of 120 microgrammes per cubic metre, was recorded on Monday in Thailand-Myanmar bordering Mae Sai district with the poor visibility of about 300-500 metres.

Read more: MCOT