If it helps any fiberglass isn’t called that for funsies. It’s actually made of glass fibers in a resin. It’s not any more flammable or conductive than any other kind of glass/resin combination. The most important safety advice for using it is to wear gloves and protective glasses, because having lots of tiny glass fibers break off in you is super itchy, and your hands are right up in there, and itchy eyes are just the worst.