fireproof

adj

1. Resistant to damage from fire.

   “The fireproof safe will protect documents inside for up to four hours in a standard house fire.”

   “When I was in the States, three years ago, the head porter at one hotel took pains to impress on me that the building was absolutely fireproof.”

verb

1. To make resistant to damage from fire.

   “I hastily fireproofed my clothing somewhat by pouring a bucket of water over myself before dashing into the flames.”