Kitchen Table Debriefs - Hostile Fire Events (Part II)
Edward M. Raposo
In this “Kitchen Table Debrief” I will finish the discussion of some of the more likely Hostile Fire Events you may encounter on the fireground.
In PART I, we began discussing the most common hostile fire event, Flashover. Since then, I have been discussing this with colleagues and doing more research. Don’t worry; nothing has changed!
I would like to address a particular phenomenon, though. My research includes some sources from over forty years ago (when I was in grade school), to the latest IFSTA Essentials manual (version 5). Growing up I learned about the “fire triangle.” Then, when I joined the Fire Service in 1991, I learned about the “fire tetrahedron.” The basics of FUEL-HEAT-OXYGEN were not wrong, but they were simply expanded upon to include the chemical reaction – oxidation.
Likewise, I was originally taught that combustion goes through three stages, as explained in IFSTA Essentials manual (version 2):
2. Free burning
3. Decay. (Flashover occurs between the growth and free burning stages)
Now, recruits are taught that combustion goes through four stages:
3. Free burning
4. Decay. (Flashover occurs between the growth and free burning stages)
IFSTA Essentials manual (version 4) enumerates five stages, making Flashover its own stage. It doesn’t change the behavior of the fire. For the purposes of the discussion here, it doesn’t matter what the number of the phase is. Regardless of the stage number we assign it, flashover will still occur when the room gets hot enough, and it will occur between what we call the growth and free burning phases. These differences do not, in my opinion, make previous statements wrong.