How To Choose Six Common Masks

There are many kinds of masks, how to choose? Zhang Yucheng of the Disinfection Department of the Infectious Disease Prevention and Control Institute of the Municipal Center for Disease Control and Prevention recently introduced various masks use scenarios. Jin Xiangyu, a professor at the School of Textiles and Textiles of Donghua University, also gave answers to the children's masks needed for returning to school.

Disposable medical mask: daily use. The bacterial filtration efficiency (BFE) of disposable medical masks is ≥95%, and the ventilation resistance should not be greater than 49Pa/cm2. This type of mask is suitable for ordinary people to use when they are not in contact with patients with symptoms such as fever and cough. Generally, it is enough to wear them when going out or taking public transportation.

Medical surgical masks: available in hospitals. The bacterial filtration efficiency (BFE) of medical surgical masks is ≥95%, the pressure difference between the sides (equivalent to ventilation resistance) is not more than 49Pa/cm2, and the particle filtration efficiency (PFE) is ≥30% (non-oily particles); it must also be pierced through synthetic blood Penetration test (2mL synthetic blood 16.0kPa, no penetration inside), which is to test whether the mask can be penetrated by splashed blood, droplets from sneezing, etc. This type of mask is suitable for the hospital environment. If you have long-distance contact with patients with fever, cough and other symptoms more than 3 meters, it is recommended to wear them when going to the hospital or visiting patients.

Medical protective mask: Use when touching patients. Medical protective masks can filter most microorganisms and can resist splashes of blood and body fluids to a certain degree. The outer surface has a certain degree of waterproofness and high adhesion. Its particle filtration efficiency is ≥95% (non-oily particles), and it has passed a higher standard synthetic blood penetration test (2mL synthetic blood 10.7kPa, internal impermeability), and has a certain surface moisture resistance. This type of mask has better protective effect, but it is less comfortable and will make users feel uneasy breathing. Generally used when professionals come into contact with patients with respiratory infections.

KN95 mask: available for short-term contact with patients. The filter elements of filter-type respiratory protective equipment are divided into KN type and KP type according to the filtering performance. For microorganisms, just look for KN, the number "95" refers to the level of filtration efficiency. KN masks only test the filtration efficiency of particulates, and have not tested the synthetic blood penetration, surface moisture resistance and other indicators. This type of mask can block the virus when used for a short time, but cannot be used to contact patients who may have splashes or contact patients for a long time. It can be used by ordinary people and medical personnel who have been in contact with patients with new coronary pneumonia for a short time, but cannot be used by professionals who have been in contact with patients for a long time. In addition, the N95 mask is a mask that meets American standards. Chinese medical protective masks are a type of N95 masks, but not all N95 masks are medical protective masks.

Disposable children's mask: change every day. Should I stock up child masks in preparation for school? Under normal circumstances, it is sufficient to use disposable masks to change once a day. It is necessary to choose a children's mask of the appropriate size. The specifications are large (L), medium (M), and small (S). Teach children to press the metal strips on both sides of the nose bridge with both hands when wearing the mask, so that the upper end of the mask is close to the bridge of the nose. Stretch the mask down without leaving any wrinkles.

Children's masks printed with cartoon patterns and colors may not be safe. The new "Civil Hygiene Masks" stipulates that the fabric directly in contact with the skin must not be dyed. However, this requirement does not apply to the outer layer of the mask. Whether the outer layer of the mask is dyed and whether there are various patterns is designed by the enterprise itself. The standard does not require it, but Buy beautiful masks carefully. The pigments used in children's masks should meet food-grade standards. Wearing masks dyed with chemical materials for a long time will cause negative effects.