Many people have asked about mask decontamination. If you have a cloth mask, then obviously you can wash it with soap and water then dry. For surgical or N95 masks, it's best to keep 3 for yourself to use every 3 days to let any virus decay. But to actively kill virus... (1/n)

There are 3 methods for N95 (steam, heat, UV) and 2 for surgical masks (heat, UV). These methods kill bacteria too, so allow mask sharing. The results for N95 are summarized in the table below from Stanford colleagues. I will now discuss these 3 methods in detail... (2/n)

The steam method is 10min above boiling water. For N95s, filtration efficiency drops from 97% to 95% after one time. Followup results show this drops to 85% after 5x. For surgical masks it reduces filtration after 1x ( https://mp.weixin.qq.com/s/3QYVWO4kj5qwuSHnhcM9uQ), amount unspecified... (3/n)

The hot air method is 70-75C for 30min. Followup results show no drop in N95 function after 10x. This is likely to work for surgical masks too. BUT home ovens don't set 75C=167C well; they also heat unevenly so a mask may get partly melted. Thus not recommended at home... (4/n)

The UV method is placing in a 8W 254nm sterilizer for 30min (with mirrored insides to maximize exposure). Hospitals have these but I would not recommend getting one for home; you might as well buy some surgical masks (try http://superbuy.com ) and rotate through them... (5/n)

Finally below are the conclusions of a Stanford document recommending the 75C heat and UV methods with additional details. More discussion in my #coronadeck

Another resource with excellent technical information: https://utrf.tennessee.edu/information-faqs-performance-protection-sterilization-of-face-mask-materials/