"Most travelers cooperated very well as they had learned what to expect from the procedures from our information online or friends who had returned to China," said Ji from the Changning District Civil Affairs Bureau.

The testing venue in Changning district, away from residential communities, is a new park not put into use yet, and such places in the open air with good ventilation are preferred to keep travelers and workers safe, Ji said.

Through the whole journey on the bus and at the testing venues, travelers are required to keep space between them to stay safe, according to the workers.