How to protect a steel beam supporting wood floor?

[Yikes]

Type V-1hr , 3 story building has a steel beam supporting 2 floors an a roof , so it needs 1 hour rated individual protection. It's a typical detail, steel I beam has a 3x nailer on the top flange, and the floor joists rest on that.

I can easily wrap the bottom and sides, but how do you protect the top of the flange?
I know that 704.3 (exception) says we only need protection on the 3 exposed sides, but the IBC handbook implies that it's for assemblies that have been tested with that kind of exposure. Problem is, most of the steel beam assemblies in UL, etc. are showing steel deck above, not a wood nailer. Is that still applicable?

 

[RLGA]

Reread the exception. It states that the exposed surfaces need only have the protection “provided the extent of protection is in accordance with the required fire-resistance rating.” This means that if the beam per the UL assembly, for example, requires 1-1/2 inches of spray-applied fireproofing, then you must provide 1-1/2 inches on all exposed sides (i.e., “the extent of protection’).

The bottom and sides of beams are the most vulnerable since they will be exposed directly to the heat. The top side of beams will see very little heat, since heat will rise.

 

[SCBO1]

RLG,
Could you protect a beam and post with a UL type-X drywall design?