Region 16 environmental boss Halem Jehmarigan said the safe dust particle to air ratio is 120 microgrammes per cubic meter (µg/m³). He explained that air-quality tests had showed considerably less than 120 µg/m³ and that the smog was expected to disperse quite quickly anyway.
Southern meteorological centre director Payao Muang-ngarm confirmed Mr Jehmarigan’s theory that the smog would not last long. She said that tropical storm Koppu was driving the smoke forward but was expected to make landfall either tomorrow or the next day. Once Koppu arrives the rain should break up the haze.
Haze blanketing the southern half of the Thai peninsula as well as Malaysia and Singapore has become an annual issue. It is caused by Indonesian farmers employing a slash-and-burn procedure to clear land for forthcoming crop cycles. It rarely lasts more than a few days at a time, but has been known to hit the critical 120 µg/m³ level.
Forest fire smoke covers southern Thailand and Hat Yai
News in AsiaSmoke from burning forests in Indonesia has covered the town of Hat Yai and the surrounding region in the far south of Thailand since the beginning of the week. While the haze is clearly visible in the sky local environmental officials say it is not yet a health risk.