The Medical face mask is divided into 3ply, with a filter layer in the middle, which can filter bacteria or viruses and prevent pathogenic microorganisms from invading the human body and causing respiratory diseases. Medical surgical mask are divided into medical surgical masks and medical N95 type masks. Medical surgical masks can filter about 30% of bacteria or viruses in the air to prevent them from invading the human body. Medical surgical masks are suitable for the general public. For people working in the epidemic prevention and other departments, it is recommended to wear medical N95 masks, which can filter more than 95% of bacteria or viruses in the air to avoid invading the respiratory system of the human body, while ordinary masks have no filtering function and only prevent and keep warm Role.