Electric cooker an easy, efficient way to sanitize N95 masks, study finds

Please don't disinfect an N95 or N100 mask with alcohol (of any sort). It will dissolve the plastic fibers of the filter.

this will damage n95 masks

I'm also wondering, IIRC rice cookers rely on the temperature of the pot not exceeding 100C until all the water has evaporated (which is why getting the correct rice/water amount is important). Without any water in the container I would expect the pot to quickly exceed 100C and shut off.

Mine certainly seems to provide no way to maintain such a temperature, I'd guess it'd just switch to "keep warm" and AFAIK that's nowhere near 100C (maybe 60~70).

Wouldn’t that jeopardize the filtration ability of these masks by affecting the fields of the electrets under heat?

There's no reason you can't run these pots without water (in theory). I don't think you'd damage the heating elements themselves. This is an issue for heating wire like NiChrome where if you put a high current through it, it'll melt. The elements in a slow cooker could probably handle a much higher current than you would normally use. And obviously the elements themselves can withstand the nominal operating current. I'm assuming a slow cooker/crock pot, not a rice cooker. The one I have at home is very very simple, electrically. Rice cookers are a bit more complicated and might be more finnicky because they have to go through some fairly accurate states within a short amount of time (and make assumptions about the level of rice/water in the cooker).

It probably depends if your pot has a thermostatic control or not. Some pots might damage their coating if there is no "load" to sink the heat into. Fancier units might shut off if they detect that they're being run empty. Cheaper pots might put out enough heat that if nothing is in them, they'll damage the non-stick. But if your pot is designed to hit a set temperature, it should be OK regardless of whether there's anything in it.

Anecdote - our milk frother (a cheap Lavazza Mi Moda) has fill levels for heat/foam, but is also clearly thermostatic. The second time you run it (say if you make two cups back to back), it takes much less time to indicate it's finished when it starts from warm. My guess is that it's designed to heat the milk up to a preset temperature (measured using the wall of the chamber) and then it ramps up the whisk for a preset period of time.

I really doubt cheap slow cookers use PID loops to control the temperature. They're normally "bang bang" relay driven - they hit a set temperature and the elements turn off. When the temp decreases they turn on again. Perhaps if there's no load in the cooker they'll keep over/undershooting.

You might be able to put a piece of something like cast iron in there to heat up initially, then when the unit is up to 100C, take it out and replace with the towel/masks. My guess would be you want to avoid an initial thermal runaway more than anything else. Also if you're using a crock pot for covid sterilisation, maybe you don't want to use it for food!