The Bangkok Metropolitan Administration (BMA) has prepared measures to curb the hazardous ultra-fine PM2.5 dust pollution, which is expected to escalate to a high level from Friday until Sunday.

If PM2.5 dust levels hit more than 76 microgrammes per cubic metre, the red level for dust pollution, in two to five districts, the BMA's Department of Education will consider suspending classes at schools across the city for 15 days, Deputy Bangkok Governor Chakkapan Phewngam said on Thursday

However, if the situation is even worse, with five or more districts being declared red zones, the Bangkok governor may consider ordering a shutdown until the situation returns to a safe level, Mr Chakkapan said.

Aside from this, the BMA is preparing to step up controls of PM2.5 dust sources, particularly traffic emissions, the most common cause of the dust, he said.

The BMA will also be working together with the Pollution Control Department to inspect more sources of PM2.5 dust, including factories, he said.

Some factories may be ordered to stop operating due to the serious pollution situation, he said.

An adviser to the Bangkok governor said he had received a report that the PM2.5 dust levels will likely hit 37.6 to 75µg/m³ in Bangkok from tomorrow to Sunday.