BANGKOK - Several parts of southern Thailand were shrouded in haze caused by forest fires in Indonesia on Monday (Sept 23), with air quality reaching "unhealthy" levels in Phuket and Hat Yai.
The Air Quality Index (AQI) in the popular island resort of Phuket hit 158 at 9am before dropping to 119 at noon, according to the Beijing-based real-time website aquicn.org.
The AQI in Hat Yai district in Songkhla province surged to 161 at noon. Haze was reported in Yala province from last Thursday to Saturday before dissipating.
An AQI reading of 0 to 50 is classified as good while 51 to 100 is moderate, 101 to 200 is unhealthy, 201 to 300 is very unhealthy, and 301 and above is deemed hazardous.
The PM2.5 particles in Phuket were measured at 57 microgrammes per cubic metre, a level considered to be harmful to health, according to the Pollution Control Department.
The Department of Disaster Prevention and Mitigation has issued warnings against outdoor activities, including driving, sailing, and lighting a bonfire, while residents have been urged to wear masks, and keep doors and windows tightly closed.
The haze is thicker on the island's beaches than its city centre, as mountains block some of the smoke blowing inland, said Mr Charn Jindachote, the department's official based in Phuket.
"Smog happens in Phuket around this time every year as a result of agricultural burnings in Indonesia, but this year is the worst, as there is currently no rain and not enough wind to bring the smog elsewhere," Mr Charn said.
Phuket International Airport confirmed to The Straits Times that no flights have been cancelled or disrupted.
Local authorities have sprayed water in affected areas to alleviate the problem.
Besides Thailand, haze caused by the fires on Indonesia's Sumatra and Kalimantan have also affected neighbouring Singapore and Malaysia.
It is an annual problem during the dry season where farmers use the slash-and-burn method to clear land to grow new crops.
This year's haze has forced thousands of schools in Indonesia and Malaysia to shut. The air quality in Singapore remained unhealthy on Monday morning, with the 24-hour Pollutant Standards Index for all regions over 100, but showers expected later in the day could bring some relief.