During the new coronavirus outbreak, it is best to choose medical surgical masks, medical N95 masks or disposable general type medical masks. The first two have the ability to effectively prevent virus attack, while ordinary disposable medical-surgical masks can also prevent virus attack, but the protection ability is relatively poor. At present, these three masks are in shortage of resources and are mostly used for medical and nursing staff or police and community workers. For ordinary people if they do not choose the above 3 kinds of masks, they can also choose industrial type masks, general KF94 masks, industrial N95 masks, which can effectively prevent droplet transmission, and other industrial masks can also prevent droplet transmission. Although it cannot prevent coronavirus transmission, preventing droplet transmission is also an effective way of prevention. You can also choose cotton masks, but the application of cotton-type masks is not recommended in crowded places.