Defining Protection
Next, decide on temperature regimes for the beams and slabs. Typically the primary consideration is which beams will be protected and which beams will be unprotected and what the appropriate time-temperature relationship should be for these beams. Under normal circumstances, beams that frame into columns should be protected.
Here, a fire engineering strategy is used in which the floor area is divided into rectangular areas with unprotected downstand beams, with protected boundary beams on column gridlines. In this case the beams on the the central column gridline are left unprotected.
On the diagram below the following convention is used:
Blue - Protected Beams
Red - Unprotected Beams
This scheme is also adopted in Vulcan to visualise which parts of the structure are assumed to be heated and which are protected.