masks trap bacteria and shit on the inside. they absolutely do constitute a biohazard. theyre meant to be disposed of in yellow bags with black infectious substance symbols on them and destroyed. there is *no time* outside of a hospital with access to fresh stock that re-use of a facemask is appropriate or safe. if someone saw me drop a load of them in a normal dumpster in a normal plastic bag i can be hit with a corporate medical waste fine which is a multiple $10k fine.