Greater Bangkok was free of hazardous levels of toxic dust for the past 24 hours, but anti-smog measures were continuing, the Pollution Control Department reported on Monday.
The safe threshold of particulate matter 2.5 micrometres or less in diameter is set at 50 microgrammes per cubic metre of air.
Over the previous 24 hours PM2.5 levels in greater Bangkok ranged from 15 to 43mcg, the department statement said.
The lowest PM2.5 reading was on Rama III Road in Bangkok's Yannawa district, and the highest was on Phahon Yothin Road in the capital's Bang Khen district.
The department said light planes from the Bangkok Aviation Centre made 11 flights releasing water into the air over Bang Kae, Bang Bon, Thawi Watthana and Taling Chan districts of Bangkok. In all 50 Bangkok districts the roads were cleaned late on Sunday night.
The department expected PM2.5 levels to increase slightly on Tuesday, but forecast it would still be within safe limits.
Officials said a southerly wind had started to blow and should further alleviate toxic dust pollution.
