Back in the late 70s the Navy came up with the bright idea of switching the utility uniform (formerly called dungarees) to all synthetic (including the socks, pants, shirt, and coat). After a few unfortunate years of firefighting experience, they realized their mistake and switched back. Not fun fighting a mainspace fire and having your duds suddenly start melting into you.

Nonetheless, I still prefer to travel with synthetics. I have become accustomed to the extra comfort they afford me, especially since I've been spending so much time in the heat.

Now that I am back in the cold zone, I am wearing more natural materials, like cotton, wool, and skins. I think the best natural clothing for fire resistance has got to be leather by far. It can take an awful lot of abuse, and doesn't burn worth a darn, unless it is impregnated with oil or wax (burned up a good pair of boots trying to water proof them next to the fire one time)