Top 3 Tactical Changes from Firefighter Research

Firefighter manages a hoseline outside a residential fire

By Mark Cotter

Photo by Tony Greco

The tremendous volume of information that has been provided to the fire service from recent fire dynamics research is enough to fill a textbook, while simultaneously requiring the revision of most of the textbooks already in print. And it keeps coming. Ongoing are projects that are analyzing the unseen health hazards present at even “routine” structure fires, as well as measuring the effects of “real world” fire control tactics (i.e., the use of interior hoselines), among other topics. So much new knowledge has been produced that Steve Kerber, Director of Underwriter Laboratories Firefighter Safety Research Institute (ULFSRI), developed a summary titled “Top 20 Tactical Considerations from Firefighter Research,” which he has been presenting at conferences for years now. There is even an on-line course based on this list that you can access from their website ( Becoming familiar with the beneficial new insights that have been discovered on our behalf has never been easier.

Although having this scientifically-validated, previously-unrecognized, and potentially life-saving information so readily available–in condensed form, no less–is priceless, there remains a need to translate these changes in understanding into changes in behavior. Much has been accomplished already by the creators of SLICE-RS, which integrates the principles illuminated by the research into actions on the fireground. Although it is both practical and effective, this new approach to controlling structure fires has yet to be embraced by a substantial portion of our profession. The reasons for this are varied, ranging from, on one end of the spectrum, a lack of awareness, and, on the other end, a lack of faith in the validity of the research findings, with many contrary opinions in between (including some critics citing a dislike of mnemonics, an issue I can’t fix).

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So, with what is probably the most elegant attempt to merge the latest firefighting theory with practice still being met with resistance from many, I will attempt a more focused approach. Instead of redesigning the entire process, the few tactics that require revision will be highlighted. Instead of general concepts to think about, specific changes will be recommended. And, instead of arranging the steps to spell out a word completely unrelated to firefighting, I’ll use an equally-annoying alliteration. The intent, as always, is to present these ideas in a way that is relevant to the end-user; to bring the laboratory to the street.

As I have suggested previously, the practical result of the tons of research data on fire dynamics is that we have learned that, when extinguishing structure fires, water flow is good, and air flow is bad. While overly-simplistic, the point of again stating the obvious in this regard is to allow us to strip away the many habits and rituals the fire service has piled atop supposedly sound principles of fire control that have since been found to be incorrect. Since we now know that the theoretical foundation we built our fire attack methods upon has significant flaws, we are obligated to reconsider the resulting tactical “structure.”

For instance, applying water from the exterior of a burning building was believed to be useless and/or harmful, and was therefore resorted to only when structural instability prevented entry. (Even then, we might stretch our luck with the contradictory “Defensive Offensive” strategic “mode,” which described cautious interior operations in a building that was already significantly damaged, and was taught and practiced with a straight face and an air of confidence for decades.) Now we know that applying water to an interior space containing fire, or even heated products of combustion, will cool every area into which smoke is flowing, and that no ill effects occur if proper hose stream operation is practiced (i.e., steep, straight, and still).

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We also believed that ventilation ahead of fire attack cleared away smoke and heat, and thereby enhanced our ability to advance our fire attack and search efforts, to the point that most departments preassigned that task to early-arriving personnel. Live-fire testing while measuring interior temperatures has instead demonstrated that increasing the exhaust of smoke and heat (which requires a matching increase in the intake of fresh air), when performed prior to fire control, leads to an even greater increase in the production of smoke and heat than that which is passively released. It should now be evident to us that the impressive flames that erupt from the exhaust sites we make by removing some portion of a burning structure are not only released but caused by these actions. Although ventilation is certainly necessary to reduce interior heat and smoke, it is better to do so only when more of the same won’t be created.

In summary, we now know that it is neither necessary nor better to delay fire attack until we reach the unburned side or the interior of a structure, and that opening up a building prior to cooling the fire causes a worsening of conditions. Applying these principles to our current practices results in changes that are simultaneously simple–in that they are easy to learn and require no new equipment–and radical–in that they are in some ways the opposite of our previous methods. Of course, none of the resulting actual fireground tasks are in any way “new,” even with this enhanced insight into our actions; we still need to operate hoselines, ventilate, force entry, search, perform salvage and overhaul, etc. Instead, it is the timing or sequence of some of those operations that should be adjusted, albeit significantly.

The necessary tactical changes comprise a relatively short list of general actions that actually serve to outline the approach for controlling a fire in a structure. Like the new information they are based upon, though, each is admittedly more complex than their single-word labels suggest. (Remember, Steve Kerber has 20 considerations on his list.) Still, to better illustrate the changes mandated by our new understanding, the following steps, in this general order, represent our “corrected” instructions.

Confine, Cool, then Clear

1. Confine: Prevent air flow to fire compartment until the fire is controlled. This can be accomplished actively (close doors, place smoke curtains) or passively (avoid creating openings), and often a combination of methods is required. Certainly, the complete sealing of a building usually is neither practical nor possible, so the idea is to at least minimize air flow to the fire. When entering, open the door or window only as much as needed to proceed. Once through a door, either partially close it behind, ideally with a firefighter posted there to both hold the door closed and help feed in the hoseline, or use a smoke curtain, which will itself both block air flow and allow easy passage of hoselines and personnel. Crews previously assigned to open up a building might now be first redirected to the opposite function until the next step is completed.

2. Cool: Begin applying water to the fire compartment as soon as possible. There is no downside to reducing the temperature within a fire compartment, and no benefit to delaying that action, so it should be our primary objective when faced with a burning building, except in unusual circumstances (e.g., victims hanging out of windows due to excessive heat and requiring immediate removal). Though life safety remains our number one priority, and we need to search every space within a structure in which a victim might be located, this is a necessarily meticulous and labor-intensive process, while water application will typically have the greatest impact on the viability within an entire structure and can usually be accomplished in the least amount of time. (The astute reader will note my use of “typically,” ”usually,” and ”often,” a recognition of the lack of absolutes on the fireground, opening the door to different sequences depending on the circumstances.) The hose stream direction chosen should be whichever is quickest, whether from the exterior or the interior of the structure. Furthermore, the initial goal is cooling, not extinguishment, though accomplishing both (that is, by flowing water into the fire room) would be a bonus. Still, even though it may be difficult to identify or reach the seat of a fire from the exterior, keep in mind that a reduction in temperature that occurs in any adjacent area also reduces that of the fire room, and vice versa.

3. Clear: Remove remaining smoke and heat after fire control. The importance of limiting ventilation ceases after the fire is knocked down and will no longer enlarge when provided with additional oxygen. This third step was included to emphasize the continued importance of facilitating the exhaust of products of combustion, but only at the proper time. Fire dynamics research found that opening up before extinguishment was bad, not that it was no longer indicated. The primary goal of this action is to improve the interior environment for any known or potential victims; facilitating other interior operations by firefighters is a secondary, but still vital, purpose. Those objectives render it crucial and time-sensitive in the setting of a residential or otherwise occupied structure with potentially-tenable interior areas remaining, or where firefighters are going to be performing salvage and overhaul operations, but not as imperative, if even possible, in the setting of a more heavily-involved structure. (In general, the worst fires tend to ventilate themselves.) Again, both passive and active methods are available, and I won’t delve into the specifics here, except to point out that one of the most popular passive routes (vertical ventilation) requires the most active involvement by firefighters (climbing, cutting, and coordinating) for its completion, whereas one of the easiest active methods (hydraulic) is one of the most effective. But that’s a topic for another column.

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Although the term “confine” has previously been used in the fire service to emphasize cutting a fire off from the uninvolved portion of a burning building, and “clear” to indicate the completion of search functions, they are here intended to refer only to the process of ventilation. Also, rescue is not de-emphasized with this model so much as it is separated. As stated in the introduction, the purpose of this article was to outline the specific changes to our approach, not to create a new all-encompassing model. Just like forcible entry, size-up, water supply establishment, and many of the other “standard” fireground functions, search must be performed at the appropriate time, based on circumstances and capabilities. Some circumstances call for search to be performed before any other activity, as when the location of viable occupants is known and can be reached before that of the fire, whereas others suggest it be delayed, as when the fire itself is the easier target. Likewise, capabilities drive the sequence, with well-staffed departments better able to initiate fire control and search simultaneously. Short-staffed agencies may be forced to determine which of those two activities will best improve victims’ chances of survival. Whether using SLICE-RS or RECEOVS, the importance of a tactic is not represented by where it falls in the mnemonic, but by its ability to improve the situation at hand.

So, there you have it: Confine, Cool, then Clear. Easy, right? As if! The sole purpose of this exercise was to demonstrate the “revised” sequence of events that fire dynamics research has inspired and which, in this writer’s opinion, improves our speed, safety, and, most importantly, effectiveness. The process of extinguishing structure fires remains complex, dangerous, and labor-intensive, so we should take advantage of whatever opportunities arise that may increase our efficiency.


Modern Fire Attack: Room and Contents

From the Jumpseat: All Fires Go Out, All Bleeding Stops

From the Jumpseat: Ready? Set?…

From The Jumpseat: Negotiating Hazards

From The Jumpseat: Self-Starters

Mark J. Cotter has more than 40 years experience in emergency services and is currently a volunteer captain with the Salisbury (MD) Fire Department. He can be reached at

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