why would fire Resistance be a big factor to know as a firefighter?

Answer 1

Think about it...... How quickly will it catch & burn? How Furiously will it burn? Is it so reactive it can explode?
Will dust explode ?
Yupper ... good stuff to know when your crawling into a smoke filled area ... knowing what materials are burning and how fast the burn is handy to have.

Answer 2

It is important to have a little knowledge of your environment. You need to know how structures react to extreme temperatures. Is the structure a little weaker or a lot weaker? Might the wall hold or fail? How fast will it burn? Do I have time to go in or not?
Sometimes firefighters have to decide how much risk is present. If the risk is sufficiently high, it is in the fire fighter's best interest to let a building be destroyed while preserving the surrounding environment. In some cases entire neighborhoods are evacuated. In some cases, a decision is made to let someone die in place of an entire team and the someone. Firefighting is not easy on any level. It is harsh. You don't like talking about the worst cases, but they do exist. Even then, sometimes a firefighter will gamble to save a life and lose. No one puts down the effort. The loss is mourned. The event is documented and studied in the hope that it can be avoided in the future.
Yes, fire resistance is just one big factor. When dealing with life and death, all factors are significant and big. You live that way or you die that way.

Answer 3

The firefighter must be resistant to fire because it is his work.