Many of you know that I have not agreed with some of the findings and recommendations that have been published by UL and others conducting research related to fire behavior and fireground tactics. To be clear, I wholeheartedly support the need for research and the benefits this research can bring about to the safety and operational effectiveness of the fireground. My concern is simply that some of the findings conflict with what I have experienced as a firefighter and commanding officer.
One finding in particular that I struggle to agree with is “water does not push fire.” I’m not a scientist, but like many of you, I have a fair level of experienced-based knowledge, leading me to question their conclusion.
In previously published articles, the UL folks state that many firefighters have experienced uncomfortable conditions and even injuries when they ended up inside a burning building into which an exterior stream was being directed. And, yes, these firefighters often describe this experience as “having the fire pushed on us.”
The UL researchers talk about the writings of Lloyd Layman, Keith Royer and others who they say laid the foundation for some of these concepts. They state, “Clearly something caused those gases to move—and that something is air.” The conclusion is essentially that it is possible to entrain enough air in a fire stream to cause disruption and/or displacement of the fire gases in the compartment, thus making it appear that the stream is pushing fire. Really? So they are telling us that water does not push fire, but instead it is the air that is being pushed by the stream (water) that is pushing the fire (products of combustion).
They further state, “observation and experience may be telling me that fire is being pushed by the water being applied, but it is likely because I can see the water but not the air.” To ordinary firefighters who are operating at a structural fire, this technical explanation may satisfy a scientific purpose, but from our vantage point inside the building with an exterior stream operating into the building, it sure looks and feels like that exterior stream is pushing the fire on us.
They go on to explain that the air entrained by a fog stream (who uses fog inside?) or even the whipping motion of a straight stream can reverse the direction of the fire gases, causing what appears to be “pushing fire.” UL has a right to come to its own conclusion, but I am sticking with mine, that water does push fire!
Another point often raised is the issue of stream shape and nozzle motion while using exterior streams during offensive fire attack. I must point out here that I generally do not consider the use of exterior streams as an offensive fire attack. From my perspective, offensive describes a “moving” fire attack that is entering the structure, not standing outside, for whatever period of time it is that they are suggesting, directing a stream through a window into some fire. I say some fire because many of these experiments were conducted knowing that the exterior stream was being directed into the window of a room that was in fact the room that they set on fire. Most of us, when arriving at a house fire, simply don’t know if the fire issuing from a window is the main body of fire or an area that a larger interior room fire has extended into and has subsequently vented through a window.
So let’s get back to the stream shape and motion. Yes, I agree that “fog streams of any shape, straight streams whipped vigorously and streams operated too far from the opening may essentially ‘fill or block’ the opening.” So now we have ruled out three of the firefighter’s options: A fog stream is ineffective (but who uses them anyway?), a whipping straight stream is ineffective (but we train to use straight streams in this manner for interior fire attack), and a stream that is too far from the opening is ineffective, too (how far?). That leaves one option. Aren’t we getting a little specific here? So now UL is telling us that this exterior stream through a window option is just another consideration, but it must be conducted like nothing we’ve ever done before. No, don’t whip that line back and forth like you always do when conducting an interior hoseline attack, and no, don’t stand too far back from the window, using the reach of the stream or it will be improperly deflected and not produce the desired results, and no, don’t use a fog stream (OK, I agree).
So there you have it. Another viewpoint, another perspective so we can all share science and connect our experience to better serve our communities. What do you think?
