The levels of particulate matter from Indonesia's forest fires in the southern provinces of Songkhla, Satun, Yala and Pattani have soared above safety levels, environmental authorities said on Wednesday.
Residents in all areas were advised to continually monitor the haze situation and wear face masks outside the home at all times.
The particulate matter (PM10) reading in the four provinces was measured on a rolling 24-hour average until 6pm, the Pollution Control Department said.
Songkhla was the hardest hit with the particulate matter reading at 267 microgrammes per cubic metre, far above the safety level of 120 and up from 185 at 7am, followed by Satun at 165, Yala at 153 and Pattani at 139.
Halem Chemarikan, director of the 16th Regional Environment Office, said the levels of tiny dust particles in the South showed an increase based on the results monitored every three hours. The situation in the four provinces needed to be closely watched 24 hours a day as indications are that the situation will worsen.
The situation could last from one day to 25 days, while more rain would help to disperse the haze.
He said the haze was lingering because rainfalls were relatively scattered and winds were light. On Wednesday, there was low to moderate rainfall.
Street lights in Songkhla’s Hat Yai district and Satun town were turned on through the daytime as the thick haze blocked out the sunlight. Airports and flights in the South were operating normally, but small fishing boats could not go out to sea at night due to poor visibility.
Mr Halem advised children, the elderly and those with respiratory conditions to stay at home. People should avoid areas of thick haze, refrain from doing outdoor exercise and wear a face mask at all times when outdoor.
The public was urged to drink more water, refrain from activities that create smoke and closely follow official announcements.