Because the new coronavirus is a virus that is transmitted through droplets, there are no constant standards for masks, including specific types of masks that are not recommended in diagnostic and treatment protocols, but isolation is definitely needed to prevent droplets from spilling onto others or onto oneself. Frontline medical personnel, in the ward when facing the patient requires strict protection, the stronger the closure the better. So N95 is a very good choice, due to good containment, and filtered power capacity is also the best, but also easier to popularize. If the intensity is greater, there are masks that can achieve 99% closure or even 99.97% closure effect, but need to consider the degree of breathability, if it affects the normal work is not appropriate. Ordinary people if you normally wear N95, it will indeed be very uncomfortable, because it will be difficult to breathe, such as mask sealing is too strong, for patients with chronic lung disease, heart disease patients, asthma patients are not suitable.