Hazardous smog levels were reported in Bangkok's Bang Khunthian, Pathumwan and Wang Thonglang districts and areas in Nakhon Pathom, Samut Prakan and Samut Sakhon provinces on Friday morning.
Chayapol Thitisak, director-general of the Department of Disaster Prevention and Mitigation, said particulate matter 2.5 micrometres or less in diameter exceeded the safety threshold of 50 microgrammes per cubic metre of air over the previous 24 hours in these areas, ranging from 51 to 78mcg per cu m of air.
In Bangkok, the worst areas were on Kanchanaphisek Road in Bang Khunthian, Rama IV Road in Pathumwan and in Phlab Phla sub-district of Wang Thonglang.
Serious air pollution was also reported in tambon Khlong Nueng of Khlong Luang district in Pathum Thani.
In Samut Prakan, it was detected in tambon Song Khanong and tambon Talad of Phra Pradaeng district, tambon Pak Nam of Muang district and tambon Bang Sao Thong of Bang Sao Thong district.
Smog warnings were in force for tambon Om Noi of Krathum Baen district and on Rama II Road in Muang district of Samut Sakhon and tambon Nakhon Pathom of Muang district in Nakhon Pathom.
