BANGKOK, THAILAND - JANUARY 31: Commuters wearing masks ride the BTS train system on January 31, 2019 in Bangkok, Thailand. The Thai Government has ordered schools in Bangkok and the surrounding provinces to close throughout the rest of the week due to high levels of pollution in the city. Residents have been advised to wear masks while travelling outside. Children and the elderly have been deemed extremely sensitve groups. (Photo by Lauren DeCicca/Getty Images)
