Weather conditions trapping air pollutants in the lower atmosphere created a health risk over a large swath of Bangkok and its vicinity on Friday morning.
Residents shared photos of the early winter smog on social media through the morning.
In the severest reports, the Air Quality Index (AQI) at 7am was 214 along Rama II Road in Samut Sakhon's Muang district, 207 in Bangkok’s Din Daeng district and 204 in Samut Prakan's Phra Pradaeng district.
The AQI safety limit is 100.
The Pollution Control Department (PCD) said the air pollution was expected to linger in the area for at least two more days, into Sunday.
The amount of PM2.5 – airborne particulate matter smaller than 2.5 microns in diameter – was measured at 80-100 micrograms per cubic metre in Bangkok’s Bang Khun Thien, Yannawa, Sathorn, Thon Buri, Lat Phrao, Sampanthawong and Pathumwan districts, well beyond the safety limit of 50 micrograms, the PCD reported.
It advised residents to minimise the time they spend outdoors and to wear a face mask when they do go out, and to refrain from burning waste outdoors and from driving cars and trucks that belch black exhaust fumes.
Real-time AQI reports can be viewed on the PCD phone application “Air4thai” and the websites http://air4thai.pcd.go.th and http://bangkokairquality.com.