Hey...I am not the herbi whose opinion you are soliciting, but I did read over that and I have some thoughts on the issue too:
Thanks for posting that, first off, it's good to be challenged and to raise issues of common concern.
I think your skepticism of the types of ceramic donuts being discussed here is misplaced, based on the hazards you shared with us regarding silica-based RBA heaters.
The reason: all these ceramic donuts aren't made of
silica. They are made of
alumina (aluminum oxide) to the best of my knowledge. Various brands of donuts may have different coil wires soldered to them, some are Ti, others kanthal
(yuck) the DT wires are made of nichrome. The soldering material for the wire can vary as well.
These kinds of ceramic donuts we're discussing are all non-porous, and are quite durable to abrasive scraping. They do not emit dust or particles.
With regular use vaping melt oils, a layer of thick "reclaim" oil can accumulate on the donuts. My lazy trick to get it clean, short of a full-on cleaning, is to set the temp to 200F (the minimum) and hold the button down while i scrape it off with a flat-edged dab tool. The gentle heat loosens the reclaim, doesn't even make it sizzle, while the tool easily glides across, wiping it off and leaving an
almost perfectly white and clean and flat donut underneath.
I've done this on some donuts hundreds of times, and no visible chunks, dust, or fibers break off from the donut. Even after burning them clean by setting them to VW mode (that mode does have
some use) and heating them to glow mildly, the integrity of the donuts is uncompromised, even if you set the watts/temps too high and use it a lot. The electrical contact blows between the wire and the solder on the donut, rendering it inoperable, well before any significant particulates can be emitted from the donuts.
The guy who designs these donuts and vapes, Matt
@divinetribe, has even sent one of his latest units to a lab for an off-gassing test, and he has shared these raw lab results with me . Although it is quite detailed and I can't interpret it with much confidence, he has assured me the results were excellent, with the help of his doctor & the lab techs explaining it. IDK why, but I'm sure these results will be published soon, once they can be broken down for the layman.
But I'd encourage you to contact Matt if you have concerns about the safety of vaping with ceramics. He's quite accessible and un-pretentious, and I'm pretty sure you'll come away from a discussion with him with your concerns completley or mostly allayed.
Anyways, sorry for the long counter-rant, but I think you've got silica mixed with alumina in this case. I'd like to see the original source of that quote from another forum too, to see what other people have responded to regarding that post.
Thanks