aMedical and/or FDA classification. OUK = FDA clearance as a surgical mask with antimicrobial/antiviral agent; ONT = FDA clearance as an N95 mask with antimicrobial/antiviral agent. Washable/reusable masks do not require any certification. bAntimicrobial tests were performed only on fabric but not directly on the masks. cSingle HEPA filter provided with the mask is not washable or reusable. dReusable but not recommended to be laundered.