23 December 2019, the website aqicn.org reported that Bangkok’s air quality at 9.00 a.m. has several concerning spots

For example, Air Quality Index (AQI) at Chok Chai Police Station is 132 and AQI at Bodindecha (Sing Singhaseni) School is up to 159, etc. The AQI is divided into categories which 0-50 means air quality condition is good, 51-100 is moderate, 101-150 is unhealthy for sensitive groups and 151-200 is unhealthy. Meanwhile, the website airvisual.com revealed ranking of air quality and polluted cities according to US AQI standard found that Ulan Batar, Mongolia ranked number 1 while Bangkok, Thailand ranked 38.