At one of FB groups I have found the following figure:

Table comparing different disinfection methods

As the efficiency of disinfection methods has been tested against E. coli, I wonder, how resistant SARS-CoV-2 is? Is it safe to reuse FFP2/3 (N95/99) mask treated for 10 minutes with boiling water vapor or not?

The assumption is FFP2/3 is effective against infectious particles.

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    @Universal_learner I wonder the filter may not survive it.
    – abukaj
    Mar 24, 2020 at 11:51
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    @Universal_learner Well, I am a biologist (PhD) but virology is not my field.
    – abukaj
    Mar 24, 2020 at 13:58
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    The chart you provided appears to answer your question ("Hot water vapor"). The only problem is it's a screenshot taken from Facebook, which isn't a credible source. It took some searching but I found the original source here. It would improve your question greatly if you added that link to your question. And you may as well answer it because that's as authoritative as you're likely going to find.
    – Carey Gregory
    Mar 24, 2020 at 15:16
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    @CareyGregory The chart mentions only E.coli - that is why I have been unsure, as I do not know whether a virus may be more resistant than a bacteria. The source you have found explains, why E.coli model has been used, and that the virus is treatment-sensitive, thus I will be happy to accept your answer if you mind writing one.
    – abukaj
    Mar 24, 2020 at 15:49
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    Bacteria are alive, viruses are not. They're just a collection of DNA/RNA and some are encapsulated like this one is. They are more hardy than bacteria. Mar 24, 2020 at 21:45

1 Answer 1


Regardless of whether high-temperature steam kills SARS-CoV-2, a technical bulletin from 3M notes specifically that they do not recommend sterilizing N95 FFR masks using high temperature, autoclave, or steam as these methods cause significant filter degradation: https://multimedia.3m.com/mws/media/1824869O/decontamination-methods-for-3m-n95-respirators-technical-bulletin.pdf

  • Nevertheless the table states that the filtration test is passed after 10 cycles of moist heat.
    – abukaj
    Apr 12, 2020 at 19:26

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