The masks currently used in hospitals are medical surgical masks, which look thin and comfortable to wear, but they are also divided into three layers: from the outside to the inside are a waterproof layer, a filter layer and a comfort layer. In addition, it also meets the YY0469-2004 "Technical requirements for medical surgical masks" standard. The outermost blue layer is a waterproof layer that prevents blood and saliva from penetrating into the mask. The innermost comfort layer is white and has a moisture-absorbing effect. Don't wear it backwards.
Medical surgical masks are usually head-mounted, that is, there are four loose straps on the four corners of the mask, which are tied around the neck and head. There is a piece of metal above the mask. After wearing, the mask can be shaped according to the shape of the nose and face to make it fit the face. Medical masks are highly resistant to bacteria and viruses. In daily life, they can be used to prevent the spread of infectious diseases such as influenza and respiratory system, and can also prevent patients from transmitting the virus to others. The transmission rate of a fine dust medical mask with a diameter of 0.3um can reach 18.3, which means that the protection rate is about 81%. However, for fine dust with a diameter of 5um, the protection rate can reach about 90%. However, the filtration efficiency of bacteria is not less than 95%. Due to its good waterproof properties, it has a good protective effect on body fluids and saliva.

Disposable medical nursing masks, also known as medical protective masks, comply with the GB19083-2003 Technical Requirements for Medical Protective Masks. The mask is also divided into inner layer, middle layer and outer layer, the inner layer is ordinary sanitary gauze or non-woven fabric, usually white, the middle layer is a layer of ultra-fine polypropylene fiber meltblown material, the outer layer is the layer is non-woven or ultra-thin layer. The polypropylene meltblown layer is typically light blue. Also be careful not to wear it backwards. This highly effective medical protective mask is highly hydrophobic and breathable, and has a significant filtering effect on tiny virus aerosols or harmful fine dust. The overall filtering effect is good, the materials used are non-toxic and harmless, and they are comfortable to wear. The filtration efficiency of fine dust particles is not less than 95%. There are also certain standards in terms of size: the size of the central part of the expanded rectangular mask: the length is not less than 17cm, and the width is not less than 17cm; The size of the closed arch mask: the transverse diameter is not less than 14cm, and the longitudinal diameter is not less than 14cm. Medical protective masks must not have an exhaust valve. General medical masks that meet the relevant registered product standards (YZB), have a minimum level of protection, can only block spitting and spitting out of the mouth, and can be used for one-time health care in general medical settings, or health care activities in general wards, such as hygienic cleaning, liquid distribution, cleaning beds, etc., or to block or protect particles other than pathogenic microorganisms (such as pollen). The filtration efficiency of particles and bacteria cannot meet the standards of medical masks and medical protective masks. For aerosols with a diameter of 0.3 μm, only 20.0-25.0% of the protective effect can be achieved, and the filtration efficiency of particles and bacteria cannot meet the current requirements. The required requirements cannot effectively prevent the invasion of pathogens into the respiratory tract, cannot be used for clinical invasive operations, cannot protect particles, bacteria and viruses, and are limited to having a certain mechanical barrier to dust particles or aerosols