Epidemic prevention requires hotels not to open exhaust fans.

Exhaust fans generally exhaust air from the inside out, so the air flows from the inside out. In addition, COVID-19 can spread through the air, but this situation only exists when the concentration of COVID-19 in the air is high.

As long as the exhaust fan is designed and installed according to the specifications, it will certainly not spread viruses and bacteria. If your fresh air and the exhaust gas sitting together are inhaled by fresh air just after they come out, it will spread the virus. Therefore, in this case, it is safer to do it like a hospital. It is safer to disinfect the waste gas before it is discharged.