this was by no means an exhaustive study, but when I was buying some upholstery, I found that almost everything automotive fabric I ran across was 'fire-rated' which only meant that it would not support combustion, which may or may not be the same as 'self-extinguishing'. ( wool?)
If you're not happy with that, you can obviously hold a match or torch to it like Dan does...it's kinda fun, and an eye-opener when you see that black smoke come off of some of the fibres, and imagine the cockpit full of that junk!
I also sprayed all my existing seat cushions, carpets etc. with 'Flame-Out' from ACS I think....which made me wonder, if you Scotch-guard your fabric, does that make it MORE flammable?