Bangkokians who cancelled outdoor activities to avoid the bad smog can now go out again, with city authorities reporting PM2.5 readings dropping further below the danger level.
But it's a different a story in Khon Kaen and Loei, where toxic dust levels remain high in the two major provincial cities.
A haze update on Thursday morning by Bangkok Metropolitan Administration's anti-dust coordination centre showed that fine dust levels in all districts dropped below dropped below 50 microgrammes per cubic metre (mgcm)of air over the previous 24 hours.
Thai authorities deem any reading under the 50 mark to be a safe level of pollution. Many other countries do not.
"People can conduct outdoor activities or just go outside as usual," the centre said in its report.
Greater Bangkok has been blanketed since late last month with hazardous smog, a condition which has also hit other provinces, Khon Kaen and Loei in particular. (continues below)
Officials of the disaster prevention and mitigation office in Khon Kaen spray water on Thursday, as the city battles air pollution now worse than Bangkok, where the air has cleared. (Photo by Chakrapan Natanree)
Although the weather conditions are improving in the capital, light aircraft will continue to make cloud-seeding flights over Bangkok and other provinces, Surasee Kittimonthon, the director-general of the Royal Rainmaking and Agriculture Aviation Department, said on Thursday.
A helicopter crash during a training session in Nakhon Sawan on Wednesday that injured a pilot and a flight engineer will not affect the operation, he said.
The Pollution Control Department has warned residents of Khon Kaen that toxic PM2.5 smog levels of 101 PM2.5 mgcm in Muang district continue to pose a health problem.
Loei's Muang district was another health-risk area, with PM2.5 readings at 109.