RANDOM THOUGHTS
STRATEGIC FACTORS BY TOM BRENNAN
What is a strategic factor? As some texts point out, the concept is derived and handed down from science. When applied to firefighting, it is an element(s) about a particular fire that if not adequately dealt with or overcome will result in losing more of the structure, breaking down command, or changing to a less aggressive strategy before injuries occur on the fireground.
GOTHIC CHURCH
A good example is a fire in a Gothic church or cathedral—a large, peaked roof, truss-lofted, steepled, Gothic church structure. Is there anyone out there who has ever saved one? (I’m speaking of a full-blown, extended fire and not one set just to cover the pilfering of a poor box.) America does not usually save these structures. Why? Well, one reason is that the strategic factor is so hard to overcome.
Vertical ventilation. We must be able to provide a large and expanding hole in the roof of such a structure to stop the mushrooming of fire and horizontal spread and relieve the heat sink of the roof shape. Today with modern versatile tower ladders it may be possible, but yesterday it was near impossible. The roof pitch was too severe, and firefighters could not work unsupported. Support could not come from the simple 14or 16-foot hook ladder. The expanse of these roofs from bearing wall to roof ridge was enormous. The bearing walls were usually perpendicular to the street, making it extremely difficult to place an aerial turntable at the right point to get the right angle for the firefighter to get to the right place. Roof material was more often than not slippery, hard, loosened tiles and slate. The needed vertical ventilation was never possible to accomplish —at least in the scope needed for the fire and its spread below the roof.
TAXPAYER FIRE
Another example is the taxypayer fire. These are one-story (some two) strip stores built cheaply (to pay taxes on empty property ) and built to burn. They have common attic space or cockloft, flimsy partition walls between store occupancies, and if a cellar is present, it is common to all stores.
Fire in these occupancies is an immediate exposure concern on arrival. If you ever think of opening a business, rent the end store in these complexes. The fire never seems to start there. It’s always in one of the middle stores with exposure problems on both sides overwhelming response crews on arrival. Here, too, are strategic factors that if not overcome will cause us to abandon the aggressive interior attack and lose more occupancies than planned— perhaps even the entire structure. What are they?
Vertical ventilation. We must be able to cut open the roof at the hottest spot, as safe as possible over the fire, and complete the vertical opening from outer air to the fire compartment by pushing the ceiling (all the ceilings) down and out of the way. We must further be prepared to make this original opening even larger. Put additional legs into the roof before pulling the sheathing, so if additional ventilation is needed, you already are away from the heat and can increase the size of the original hole and not be forced to make an additional hole in a second location, which will increase horizontal fire spread. I know many of you are saying that the trench or strip cut is the way to go. Not yet! Trenching is a third-alarm cut. You are giving up a significant portion of the building and creating drafts to bring fire to the opening in a much wider fan or spread. I’m not ready to give up that much of the building yet.
Horizontal ventilation. This is the one strategic factor that often is overlooked or cannot be accomplished. Without the rear of the fire —in this case, the rear of the store—opened, the nozzle team will be slowed and the interior fire situation will halt advance and in some cases blow up over and behind the crew, enveloping them in products of combustion. Depending on the nozzle and its pattern, the steam created by a wide-pattern fog nozzle most certainly will envelop the advancing nozzle team without a place to go—the rear opening of the store.
Why is this so neglected? Well, even if it’s thought of and there is sufficient personnel, we don’t send enough artillery around to do it. These areas today are built like safes. These are the alleys that kids hang out in that you hope your kids don’t even know. Doors have static bars, slide bolts, and worse. Windows are bricked up or even have solid plates welded into place. A firefighter arriving with the “extra” halligan or the six-pound pickhead axe is doomed to failure. You need the tools to chisel the bolt heads off the locking devices, a lock puller, and a key tool for the sliding bar locks located in the center of the door. And in most cases, you need the power saw to cut a door within a door. Send enough artillery to support the rapid advance of an aggressive handline to the rear of the store. That’s the secret to extinguishing the one-story taxpayer fire. More next month on strategic factors.
