I have one of these but couldn't find any refills for it, plus I think it's a small because it doesn't fit real well. Nice and compact though so when they're back in stock, I'll probably grab a medium sized one. I use them in the shop when sanding/grinding. The ones that are all filter with the little aluminum thing over the nose are junk. imho Need that silicone rubber against the face to really seal. I've got a spray painting mask too if I really want to look like a pro.
Other than a contamination issue - not sure how to deal with that, those should last forever when used only for protection against a biological threat.
Maybe with several masks, you could place a used/contaminated mask in an elevated temperature environment, for several hours, to decontaminate it?
I don't know if you saw my earlier post, but motorcycle ridding glasses is what both my wife and I use for eye protection when picking up supplies in town.