Disposable masks cannot be boiled in boiling water. Disposable masks are made up of non-woven fabrics, and the most important of the non-woven fabrics is the meltblown non-woven fabric in the middle layer. The meltblown nonwoven fabric is used to block viruses and bacteria through the barrier effect of the fiber and the electrostatic adsorption of the fiber. If boiling with water can kill the bacteria and viruses stuck on the mask, but it will also destroy the fibers of the meltblown nonwoven, the mask will lose its protective effect and can no longer resist the virus. Generally disposable masks should be replaced after 8 hours of wear, but if the mask is scarce during the new coronavirus epidemic, the mask can be hung in a dry, ventilated place where the sun can shine, and the number of times the mask is used can be increased appropriately.