I have both full sized and scout fire steels. The scout version is permanently attached to my key's. On the grounds that the only two things that I am likely to stay attached to in an emergency are my knife and my keys.

Fire steels are quite durable. The big issue with them is not damage from being knocked around, but oxidisation from exposure to dampness. Which can render them useless. The only effective way to protect them is to coat the stick with high impact polyacrylate. H.I.P. is more commonly known as nail varnish (yes, the stuff that the Ladies use on their nails). All my fire steels are coated with it. It does chip and wear after a while but it is a trivial exercise to recoat the stick as needed.

How you explain wanting to borrow your Wife's/Sister's/Mother's nail varnish is an exercise that I will leave to the student......:)