Can KN95 masks be reused

- Apr 30, 2020-

It is not recommended to reuse disposable N95 masks. If the mask is in short supply, the physical structure of the mask is not significantly damaged, and the mask can be considered for repeated use if the mask is not used for a long time. At present, there is no clear conclusion on the optimal wearing time of N95 masks abroad, including WHO, and China has not yet made relevant regulations on the use time of masks. Some researchers have conducted research on the protection efficiency and wearing time of N95 medical protective masks. The results show that the filtration efficiency of N95 masks is still above 95% after 2 days of wear, and the respiratory resistance does not change much. The filtration efficiency after 3 days of wearing is reduced to 94.7% . The recommendation given by the US CDC is that if there is no adequate supply of masks, as long as the device is not obviously soiled or damaged (such as creases or tears), it can be considered for reuse. For non-medical personnel, it is recommended to wear the mask for 3 days before changing the mask .