Fire Dynamics, Firefighting

Modern Fire Attack: Room and Contents

Firefighter applies water to fire through ventilation opening.

(Photo by Tony Greco)

By Mark Cotter

The most common type of fires in structures that we face are those which involve just a single compartment: room-and-contents fires. Putting all of our skills in play, including size-up, pump operation, forcible entry, interior hose movement, and search, they serve as an unofficial “benchmark” operation to compare our abilities with that of other crews, and form the core theme of most departments’ planning and training on structural firefighting. Handling these incidents is our bread and butter. This confidence and familiarity, though, can lead to tragic failure if deviations from the usual pattern of these incidents go unrecognized and unaddressed.

The typical features of these “routine” fires include one that is localized to a single area of a structure, access via interior passageways and/or stairs, and a lack of significant structural decay. These factors mean firefighters usually can quickly place and operate a hoseline, and need spend only a brief time operating in the IDLH environment, minimizing our exposure to the products of combustion (not counting the overhaul phase). The still-significant level of danger inherent in these operations is multiplied when any of these attributes are absent, and just recognizing, at least from the exterior of a building, that a fire no longer fits the room-and-contents definition can be difficult. Furthermore, the failure, or even sufficient delay, of any of the many steps needed for extinguishment can allow a fire to extend beyond what could otherwise have been controlled with the initially-deployed measures, and might even leave the attacking crew themselves in need of assistance. Even slight variations in conditions or actions can significantly impact outcomes.

That said, most fire departments make it look easy. Truth be told, for those who know how, it is. In an extreme example, a fire service brother once described fighting a dorm room fire at his rural West Virginia college in the 1970s. The room was well-off, with smoke and heat entering the corridor. Deploying the wet standpipe hose, but without the benefit of personal protective equipment (PPE), he crawled down the hall to the room, darkened the fire with the stream, found a brick that had been part of a makeshift bookshelf (we all had one then), threw it through the window, directed the stream out the hole to vent the room and corridor, then completed extinguishment when the smoke cleared. For reasons that were unexplained, the local fire department never responded.

My point with sharing this unusual account is certainly not to suggest that we should fight fires without SCBA, PPE, and help, but to illustrate that the “typical” room-and-contents fire provides a sufficiently forgiving environment that, even when using only the most basic measures, we are almost always successful (the fire goes out, and no one gets hurt). Such experience can be a dangerous seductress. We are lulled into complacency with repeated success, until we meet an unexpected change in conditions.

When I talk about modern fire attack (MFA) tactics to firefighters, the most common response is that they have had nothing but good results with the traditional approach of quickly entering the involved building with a hoseline and spraying water onto the fire–what many refer to as the “Aggressive Interior Attack” (AIA)–so a change in methods would seem to be “messing up a good thing.” Looking instead at incidents that were not controlled as “smoothly” –and there are always such occurrences, in every department–and some common pitfalls become evident. Hardened entryways, flashover, and structural failure all can slow or halt an AIA, and suddenly rebalance the initial risk/benefit assessment. Interestingly, firefighters usually have definite ideas of what went wrong in those instances, and it’s never a failure of the strategy. Instead, shortfalls in its execution or extraordinary circumstances are blamed. By digging deeper, and viewing circumstances through the MFA lens, it can become clear that this “tried and true” method has its limitations. Even at incidents that appeared to “go well,” it may be often through luck that injuries, or worse, were avoided. We are successful despite the acceptance of excessive risk.

In a potentially deadly contradiction, the very teams that are most adept at handling these types of fires are also the most at risk for disaster when significant obstacles are encountered. Although the rapid deployment of an interior hoseline is the key to controlling an incipient or compartmented fire, the presence of unseen barriers to this approach can leave firefighters deep inside a building before realizing that their advance is blocked, exposing them to additional hazards. These obstacles can include a fire that has become vent-limited, with combustible gases spreading throughout the building, ready to ignite above, and around, entering crews; delays in gaining access, allowing increased fire growth; difficulty locating the seat of the fire, with the apparent location actually being an extension from another area, maybe even beneath the level on which personnel are operating; and weakening of weight-bearing structural members, especially in this era of lighter-weight building construction, resulting in sudden collapse. Any combination of these complications might be at work at a fire that appears, at first glance, to be “just room and contents.” And a “first glance” is often all we take before entry.

So, how do we maintain our proven ability to control the usual situation while also increasing our odds of surviving the occasional complication? The same way we always have: by ensuring that appropriate safeguards and redundancy are “engineered” into our tactics. Fortunately, our procedures usually require only an upgrade, not an overhaul. That is, most of us need merely to build on our already honed skills, rather than having to replace or change methods significantly. We already likely have standard operating procedures, rules, or just good habits that ensure minimum PPE, staffing, and hoseline sizes for these incidents. The list below includes ways to augment and enhance those practiced techniques, and is offered as a reference against which to evaluate our current approaches.

THE FUNDAMENTALS

360º size-up: Before a team is committed to entering a burning structure, all sides of the building need to be examined for evidence of the fire’s location, structural decay, potential victims, or other vital factors that may not be evident from a single vantage point. Doing this lap while carrying a thermal imaging camera (TIC) has been shown to be an effective method for also determining the seat of a fire, providing the ability to differentiate between windows that are merely darkened by smoke and those behind which is the greatest heat signature. Recognizing the staffing restraints affecting many departments, the basics of this crucial task can be performed by a firefighter or other trusted and trained non-entry personnel (EMS, police), even using a combination of several reporters to obtain the full picture. Skipping this step is a gamble with life-or-death stakes, as too many tragedies have occurred when the visible fire in the front was merely an extension of an unseen and larger blaze on a lower level in the rear.

Full PPE, on-air, with hoseline charged: I know; this should be a given. Unfortunately, except for the PPE part, it’s often not. Certainly, advancing a dry hoseline without the hindrance of a face mask is faster and easier than that same task with a charged line while peering out of a fish bowl, but that’s like a soldier not loading their weapon or wearing body armor until the enemy is near. In both situations, the adversary might come our way first and catch us unprepared. An uncharged hoseline should be carried into a burning building before donning an SCBA mask only if you intend to operate off a standpipe.

Two-in, two-out: Again, included here for both completeness and to emphasize that it’s a rule that is frequently ignored, or at best neglected. The most basic form of rapid intervention team (RIT) and a requirement subject to federal enforcement, you would think it a no-brainer; something that firefighters would be screaming for like a labor representative arguing for workplace safeguards (which it is). Too often, though, the “rescue” clause is invoked, a convenient and often hard-to-dispute excuse for immediate entry. Still, there is no reason the next two firefighters should not be taken out of what is typically a long-line of personnel eager to enter a structure to perform less critical activities (e.g., secondary search, backup line, overhaul) and reassigning them to exterior standby duty. Having this minimal reserve on hand in case of a catastrophic failure affecting those inside is a mandatory level of insurance.

RELATED TRAINING: Attacking from the Burned Side Can Save LivesVentilation Limited Fire: Keeping it Rich and Other Tactics Based Off Science | Ventilation-Limited Fires in Residential Buildings

MODERN FIRE ATTACK CONCEPTS

(For those of you who believe the principles of modern fire attack are voodoo, or worse, you might wish to stop reading here. Though the following information may save your life, just adhering to the advice provided thus far will get you through most situations, and I’m happy enough to have provided a review of what most would consider “common ground” tactics. That said, the techniques described in the next sections, while controversial in some circles, and poorly understood in even more, have been validated in both experimental and real-world scenarios. They represent, in the opinion of a number of fire service organizations, major departments, and this writer, best practices for structural firefighting.)

Limit ventilation: Research and fireground experiences have demonstrated that decreasing the air flow to a fire is an effective method for slowing the growth of a compartment fire until water can be applied. On the other hand, the former technique of increasing air flow by opening windows and roofs, or even merely leaving the entry door unclosed, has been shown to increase the rate of combustion. Furthermore, unless active ventilation is employed with a fan or a hose stream augmenting exhaust, the additional products of that combustion (heat and smoke) will spread into the structure faster than they are released. Operationalizing this new advice can involve both passive and active measures–that is, avoiding the creation of more air flow and blocking the air flow already present. The usual and practical way this is implemented consists of simply waiting until after the fire is cooled with water before opening things up and closing the entry door as much as possible behind the hose team. The use of smoke curtains to block airflow while leaving the door itself open, or at openings that cannot otherwise be closed (as when a window has already been removed) provides additional flexibility and capability.

Fast water: The basic and necessary maneuver of putting water on the fire is listed on the MFA half of this list because it has actually been found to be even more safe and effective than we previously believed. This suggests firefighters no longer need to intentionally take a roundabout route to the fire to ensure that we are “attacking from the unburned side.” Water application from the exterior has been found to have an immediate and significant cooling effect, and the use of a straight stream does not spread products of combustion further into the structure. Therefore, we now have additional options for extinguishment, and can (and should) choose the quickest route to the fire to interrupt the burning process. This requires a rapid assessment to determine the optimum positioning for the hoseline, or even whether to use separate hoselines for exterior and interior use. (Two lines might at first seem more difficult to deploy, but most engines have multiple attack lines available. One can be stretched to the site closest to the fire by one firefighter, flowed for the 30 seconds or so required for knockdown, then merely shut down and put down; that firefighter may then join up with another on a hoseline that had been taken to the entry point. Depending upon the distance from the ideal water flow position to the entryway, using two hoselines may be easier and faster than having to reposition a single hoseline from one location to another.) To take advantage of this increased flexibility it is vital that various hose placement evolutions be practiced, but no more so than we must drill on all of our skills in order to maximize efficiency and build muscle memory.

Cool the gases: Although this tactic might be considered as just an extension of the “fast water” concept and was also inspired by the findings of recent fire dynamics research, considering it merely an “option” could be a deadly mistake. The burning of modern furnishings and finishes has been shown to cause a fire to become ventilation-limited in as little as three minutes. In that state a fire continues to produce smoke and heat, but little or no flame. Since we now understand that smoke is fuel and that it is often already hot enough to ignite if sufficient oxygen is provided for the resumption of combustion (as can suddenly occur when a window fails), it is in the interest of self-preservation that we should apply water to any dense smoke overhead while making our advance to an uncontrolled fire. A TIC can help us determine if such a step might be delayed, but, lacking such a device, spraying water overhead and observing the effect is both enlightening and effective. If the stream is heard to sizzle as it is converted to steam, continue the water flow until that reaction ceases. If the water merely splashes back onto the floor, shut down the nozzle and advance, periodically performing an overhead heat check with a quick spray of water until the seat of the fire can be reached. Of note, even though this technique is carried out remote from the involved room, it also removes energy from the fire compartment and reduces its intensity, so that the cooling is not merely in the immediate area of the hose stream.

Firefighters have been successful in controlling structure fires by translating our knowledge of fire behavior, building construction, and available interventions into comprehensive procedures that maximize our safety and capabilities, then by practicing those techniques until they become almost automatic. We identify problems, determine solutions, and drill repeatedly to reach and maintain proficiency. However, ongoing improvements in our understanding of compartment fires and the effects of our tactics (water flow is good, air flow is bad), as well as the evolution of structural components and contents (they burn and fall down faster), mandate a continuous reassessment of these methods, with adjustments as necessary. Using the proven measures listed above to shore up our handling of these types of incidents provides additional flexibility, and improves our ability to manage the less frequent, often unseen, but potentially deadly complications that can arise.

Although we could manage most room-and-contents fires like my friend did–cowboy-style with just a hoseline and guts–no department would even suggest such recklessness. With the proven effectiveness of limiting ventilation, using exterior streams, and cooling smoke, performing an interior attack without these tactics, and instead counting on reaching and controlling the fire before our PPE fails, should be viewed as similarly irresponsible and ill-advised.

MORE FROM THE JUMPSEAT

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. CotterMark 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 [email protected]