We often receive requests from the users of filter facials (masks) of the type FFP2, N95, KN95 and the like, regarding the possibility of washing, cleaning or disinfection of the same.
The 3M has divulged a technical technical bulletin in these days in which it clearly specifies that No attempt is recommended or supported to sanitize, disinfect or sterilize filter facial respirators (masks) 3m.
The data and references of the studies conducted, as well as the in-depth links In the attached circular.