Teflon is inert at room temperatures. If it breaks down when I get my frying pan too hot, it doesn’t seem like it’s an optimal choice for firefighters gear.

It wouldn’t surprise me if the foam is a way more significant exposure source, though.

You can improve the situation somewhat but you’re never going to get a prebuilt like that as clean as you see other people’s diy builds with parts chosen taking aesthetics into account.

“Zero Knowledge Encryption” is the reference but I’m not sure how it applies here.