Much of Bangkok was covered with unsafe levels of PM2.5 dust, averaging 72.6 microgrammes per cubic metre (µg/m3), from 5am-7am on Tuesday, according to City Hall's daily air quality report.
As of 7am, PM2.5 levels in Bangkok ranged between 61-93 µg/m3 in 69 areas - exceeding the government-set safe limit of 50 µg/m3.
The highest levels were recorded at the office of Bung Kum district (93 µg/m3), followed by Seacon Square department store in Prawet district (87 µg/m3), Chalerm Phra Kiat Park in Min Buri district (87 µg/m3 ), Lat Krabang Hospital in Lat Krabang district (86 µg/m3 ) and the office of Khlong Sam Wa district (85 µg/m3).
The fine dust level at Lumpini Park in Pathumwan district was 61 µg/m3.
According to a City Hall forecast, unsafe dust levels in Bangkok were likely to go up on Tuesday and Wednesday. Air quality was expected to improve from Thursday on because a southerly wind would help blow away the dust.
The Air Quality Index reading in Bangkok on Tuesday morning was 159 — any reading above 150 is unhealthy for everyone.
Bangkok air quality map - IQAir