Comrades in charge of the relevant departments of the Ministry of Industry and Information Technology: Masks have an expiration date. No matter whether it is a manufacturer or a hospital, there will not be a large amount of stockpiles in non-special circumstances. For N95 masks, protective clothing, etc., the hospital usually does not reserve a lot. On weekdays, they will receive a mask according to a certain amount, but this amount is only enough to protect the medical staff for their own use. The inventory of medical surgical masks in many hospitals is about a week.