BY ALAN BRUNACINI
We have recently talked about two really important fireground subjects: fire behavior and water—its characteristics and how it is delivered. We used the reference “Think like fire/water.” Fireground attack action is fast and furious, and we typically do not have the ability to waste a lot of time being surprised by the magic of combustion or the reaction of water being converted (cooked) by the fire. It is really smart to understand the basic details of any battle before the fight begins, because you won’t have time to “break out the books” once the fire starts shooting very real thermal/toxic/collapse bullets at you.
The fire/water connection really describes the very basic essence of firefighting. We have stated over and over that when a fire is present, you really don’t “arrive” until the water bounces on top of and around the fire. Everything you do to get enough water delivered to the right place at the right time is critical and necessary, but the business end of what you do is based on how fast and completely you can get burning stuff wet.
This month, I would like to talk about where the fire/water dance mostly takes place—inside and around a building; that’s why we call it “structural firefighting.” Firefighters who want to live a long and happy life must study and learn how buildings are built, arranged, maintained, and managed simply because this is the field where we play firefighting.
A lot of what we do on the fireground is based on military/war fighting tactics. The military is very expert in managing high-risk, compressed-time tactical engagements. We can (and should) learn a lot by studying its history and techniques. A critical factor in military operations is based on the details and dynamics of “terrain.” It is pretty tough to survive and win the battle if you don’t understand the layout of the battleground. Military commanders expend a great deal of effort to gather information about the physical characteristics of the area of engagement and the current and projected tactical status of the enemy in that area. Recon units gather information that is sent up the chain of command, analyzed, and then translated into intelligence that becomes the basis of strategic decisions. Our incident command and control system must follow the same process.
Now that you are a firefighter, you must constantly approach and evaluate (size up) your physical surroundings and then automatically imagine that they are on fire! You simply must become an obsessive building watcher. Wherever you are, automatically ask yourself what are the geography and geometry of what you can see and how that physical profile would affect firefighting operations. Developing this instinctive, natural “preplan wherever you are” creates a continual level of attention and awareness that causes you (in effect) to quietly preplan every place you go. The preplan must connect the conditions you see with a conscious plan on how you would tactically react (get in/operate/get out) to what you are looking at.
We said earlier that it was dangerous and painful to be surprised by the physical properties and reaction of fire and water. The same applies to how you approach and react to a burning building. The more you have learned (before the fire) about the structural characteristics and behavior of buildings that are on fire and the details and dynamics of how firefighting operations connect to structural conditions, the fewer surprises you will live through while you are trying to evict a fire in that building.
You must study and understand how buildings are constructed, what holds them up, and what causes them to fall down. They are held together with fasteners and connectors that create the capability for that structure to overcome gravity; gravity is a dirty rat when it comes to buildings because it is always trying to pull the physical structure down to the earth. When a building burns, direct fire contact destroys virtually everything, including the connectors. When fire burns up the connectors (along with everything else), it destroys the structural integrity of the structure simply by disconnecting the connectors; if the fire is not controlled, eventually, the destruction will continue and gravity may win. When gravity has its way, the structure collapses.
Older buildings were built out of heavier components and were better connected, mostly with lots of big nails, plates, and bolts so they would stay together longer. When they burned, we had longer offensive periods to operate inside them before they collapsed on us. Today, you will sit around the kitchen table and hear the old guys gripe about modern lightweight construction. They will critically compare new buildings to the traditional heavy battleship buildings they built “in the good old days.” Today’s buildings are “engineered” in a way so that as little material as possible is used in their construction. A smart guy said, “We traded mass for math!” Modern construction techniques produce very strong buildings that are very “efficient” until they catch on fire—then both the components and connectors quickly fail (read: collapse on us/under us).
Although lightweight buildings fail quickly, don’t be distracted by the word “light” when it comes to potential injuries. Lightweight is not light. Remember, lightweight trusses are delivered on an 18-wheeler and are put up with a crane. When they collapse on you, they quickly and effectively murder you. Also, don’t be distracted when it is said that traditional construction will stay up longer when it is on fire. It will, but every weight can collapse if it burns long enough.
The punch line of all this is that a building is just a bunch of separate, connected pieces that are stuck up in the air; any physical assault (fire, flood, wind, vehicle, falling tree, meteorite, and so on) with more power than the structure’s resistance will cause the building to fail (read: disintegrate/blow away/fall down). As you come in contact with the built environment, ask yourself how what you are looking at will “behave” (Tom Brennan phrase) when it is burning.
What we should extract from all this construction talk is that most fires start in the contents of the building. If they are not extinguished pretty quickly, they will extend to the interior finish, generally the wall covering (think of interior finish in terms of dermatology). If the burning interior finish is not extinguished pretty quickly, the fire will burn through the inside wall covering and will begin to involve the structure (think of the structure in terms of orthopedics). Fires that start on the outside of the building do the same thing as those that start on the inside, only they burn through the exterior finish to get to the structure. If the fire is not extinguished pretty quickly, the fire will continue to burn the structural components, and either the fire will burn up all the fuel (and not collapse) or the structure will collapse.
I have been forever fascinated watching buildings burn when those I thought would stay up fell down and those I would have bet were about to collapse stayed up all night. The point of this observation, in addition to my inferior collapse prediction skills, is this: Never, never, ever trust anything heavy above you if there has been a fire in that zip code.
Now that I have made you a compulsive, neurotic building watcher, as you go about your daily rounds and look at built places, you must begin to pay attention to some really pretty simple, but absolutely critical, physical characteristics. As you routinely approach an area that leads to and around a building, note where the structure is in relation to your ability to drive a fire truck up to it. In many urban places, the buildings are adjacent to the street, and you can drive rigs up to and effectively access the front of the structure with pumping and aerial apparatus.
Many times, we reach the back of these same buildings through a narrow alley. We do not have a lot of position options operating in an alley and many times are “trapped” in between buildings on both sides. Through the years, our service has had some really bad experiences operating in alleys. So, on your tactical planning tour, try to imagine how you can effectively protect yourself if you want to come inside from side C (the rear). You also should ask your older colleagues what their thoughts and experiences have been operating in limited-access places like alleys, long driveways, and one-way-in/one-way-out access situations.
You must develop both the ability and habit to always be evaluating how you can get into and out of (round trip) the local physical layout of the fireground. It is smart to do this before the fire, when you can visit/observe/plan/log wherever you are when you are doing all the regular stuff you do moving around in your regular life. It may be smart to not tell your significant other that you are preplanning the parking lot and front and rear doors of the theater while you are on your date. Thank heavens for quiet multitasking.
Once you get inside the building, you must evaluate the interior layout. Always remember that the fire can easily go anywhere you can go; those places are called “public” places. They are areas like entrances, hallways, stairs and landings, foyers, lobbies, vestibules, and open public demonstration areas. Under fire conditions, we maintain control of the inside of the structure when we protect those areas. Conversely, if we lose those areas to the fire, we essentially lose control of the interior, and we lose our offensive operational capability. As you visit these public places, imagine how hoselines must be extended and operated to keep the fire out.
We will continue our fireground terrain familiarization discussion next month.
Retired Chief ALAN BRUNACINI is a fire service author and speaker. He and his sons own the quarterly fire service magazine BSHIFTER.com and the Blue Card hazard zone training and certification system. He can be reached at alanbrunacini@cox.net.
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