RE: microwave for decontaminating a mask

I'd never use a microwave to decontaminate a mask myself.
A microwave depends on polar molecules (in the water) to heat up whatever you put in it. Since this is mostly liquid (drink) or food (containing water)
the microwave does a fairly good job of heating its contents uniformly and to a good depth.

Putting something like a mask in it, that consists of various different materials (filter material, possibly a valve, metal strip, flexible straps, etc.) I'd be very concerned about uneven heat accumulation with potentially detrimental effects.

I am concerned that if the directions of the 'microwave method' aren't followed EXACTLY, this may potentially result in a compromised/bad mask that may or may not be actually decontaminated.
The article itself warns: "Several limitations and additional points should be noted. First, real-world use of N95 respirators in combination with microwave treatment may accelerate loss of mask integrity. Therefore, the ability to preserve function during 20 microwave sterilization treatments should be interpreted with caution. Second, in this study, distilled water was used for microwave steam generation for assay standardization. Tap water is more generally available and is less likely than distilled water to superheat and result in potential scalding."

If I have time, I might place a mask in the microwave (with and without the posted 'steam method') and then take a picture with a thermal imaging camera to see if my concerns are based in fact...


I much rather heat the mask slowly and evenly for a predetermined time, i.e. my sole-purpose toaster oven heated to 70°C with a digital display, and a timer set to 30 minutes.
(I also double check the temperature with a digital thermometer.)