Basement ceiling requirements

I own the bottom two floors of an old apartment building in North Brooklyn. In the unfinished basement below, there are white tiles covering the entire ceiling. They say “Bell” on them with the old Bell telephone logo and are made of some kind of plaster and metal fibers. The boiler for the building is inside of its own smaller room within the basement. The walls of this room are made of thick fireproof blocks and the room is accessed through a heavy steel door, which I assume are both required for fire safety. But are the Bell ceiling tiles in the rest of the basement also some kind of fireproofing material? Do they serve some other purpose? They are breaking down and I want to replace them, or just remove them and leave only the wood rafters overhead. Am I required to hang some other kind of fireproof material in their place? Thank you!