City Hall is working overtime to prepare for the return of hazardous levels of PM2.5 dust to the capital in December, Bangkok governor Aswin Kwanmuang told media on Tuesday.
"A high-pressure system is going to cover the city soon which will blanket the capital and prevent air circulating. City officials and district authorities are working to roll out preventive measures to lessen the amount of PM2.5 dust," the governor told the media after attending a meeting of agency chiefs responsible for handling the problem.
The PM2.5 particles emitted by industrial machinery and many older vehicles pose a risk to human health as they have a diameter of less than 2.5 micrometres (more than 100 times thinner than a human hair) and can bypass the body's natural filtration mechanisms to cause damage to the lungs and cardiovascular system. The old and those with pre-existing health conditions are particularly vulnerable.
Among the measures already agreed is a ban on larger lorries -- those with more than six wheels -- from entering the city from 6am to 9pm until February, when the levels are expected to fall again.
Pol Gen Aswin said that detection systems are in place in all 50 districts, with 20 more public parks to get the technology during November, and the readings will be fed back to the public in frequent updates.
Schools have been told to avoid organising outdoors activities as much as possible and should levels become high, be ready to close for up to three days at a time, the governor said.
During these extreme periods, state offices will adjust their working hours to reduce levels of congestion and traffic pollution, he added.
Outdoors construction will also be limited or suspended during these times.
Long-term measures such as planting trees alongside roads and railway stations are also constantly being added to, according to the governor.