Fine dust levels dropped to moderate to very good levels in greater Bangkok on Wednesday morning, except in the capital's Bang Kholaem district where the PM2.5 level was above the predetermined "safe" threshold.
The Pollution Control Department reported at 9am that levels of particulate matter 2.5 micrometres and less in diameter (PM2.5) were measured at 19-52 microgrammes per cubic metre of air over the previous 24 hours.
The highest level, 52mcg, was reported along Rama III-Charoen Krung roads in Bang Kholaem district. The lowest was recorded in Bang Na district of Bangkok. The safety threshold is set at 50mcg in Thailand.
The department said light rain is forecast on Wednesday and Thursday and this should alleviate air pollution to an extent.