BY ALAN BRUNACINI
Last month I told the story of how I was a curiosity-driven firefighter, a student who was lucky enough to get to go to fire school at Oklahoma State University (OSU). The program at OSU was perfect for me: It had the answers to my gazillion questions. The program in those days covered a full range of fire department courses and a complete overview of basic fire protection. The common element in all the material in just about every subject was how critical hydraulics is to most fire protection responses. What I learned then has not changed in the past 50 years and is based on those lessons. My advice to young firefighters today is to learn to think like water.
Thinking like water requires that you first study and learn the physical properties of water and then become familiar with how we apply water on the fireground. Water controls fire through heat transfer and steam expansion. You should study the math involved in both to understand what happens when water and fire get together. This sounds simple, and it is, but watch what occurs on the fireground when we don’t get the “apply water to the fire” connection straight. You should also continually study the dynamics of water movement—it is a fluid that will naturally seek its own level. It can be pumped to increase volume/pressure; it cannot be compressed; and when it is contained (like in a hoseline), it will stop flowing when it reaches an obstruction—either on purpose or by accident.
As a young firefighter, you probably rotate from the hydrant end of the line up to the nozzle or close to it. What you do is the most critical part of the firefight. The reason it is important is that the only thing the fire responds to is water. The incident commander must overlay overwhelming water application to cover the involved and exposed fire areas to stop forward fire progress and then extinguish the fire. Although the business end of the water system (and the firefight) is the nozzle, you must develop an understanding of everything else that goes on in that water delivery system that causes water to come out of the nozzle.
The basic local water supply forms the beginning of the system that uses underground pipelines (fire mains) and hydrants to deliver water throughout the community. Learn, and develop an understanding of the distribution profile of the system and the delivery capability of the fire mains in your area. Also, examine the physical anatomy and flow coefficients of the fire hydrants; determine how much water the system can deliver in your response district.
Some areas are not covered by water mains, so tankers must be used to deliver water to the fire. If you work in such an area, study the profile of the water sources used to fill the tankers. Many times these sources are static water supplies like ponds, ditches, and lakes. They necessitate dropping and operating suction hoses to pump water along. Make friends with the pump operators, and learn the pump/suction operating techniques.
All of the mathematical calculations it takes to get water to the nozzle are determined by fire service hydraulics. Learn the details of this subject so you can understand the operating characteristics, capabilities, and limitations of supply and attack line fire stream operation. Taking a hydraulics course at your community college fire science program is a good investment in understanding these details. While we are on the subject, take all the fire science/general education courses/get a degree (you will need it later to get promoted)/clean your room/don’t hit your brother. The community college fire science teachers often are retired firefighters with a ton of experience, so you get 16 weeks of tapping into their street/technical/tactical smarts.
In our think-like-water adventure, look at the dynamics of water delivery up to the nozzle: from the water treatment plant, through the fire main, up and out the hydrant, into and through the pump intake of the supply fire pumper, pumped out the supply hoseline into the pump of the forward pumper, out through the attack lines through the nozzle, and (hopefully) directly on the fire.
First, outline that standard hydraulic journey and all the different evolutions, techniques, roles, and functions it takes to make that work seamlessly. Begin to understand how fragile all those separate, but highly integrated, steps are. Everyone involved must do their part effectively; if they flub their part, the operation (i.e., water flow) stops.
You will notice as you get more experience that a group of your elders engage in a certain amount of screaming and swearing during hydraulic operations. When the water stops, the next guy generally forcefully uses adult words to “articulate” his frustration with a dry line, a working fire, and a street full of spectators. Things like bad pumper spots, problems getting into proper pump gear, dysfunctional valve operation, vehicles parked on hoselines, flooded hosebeds, ruptured/burned-up hoselines, seriously kinked lines, pulling lines around corners, and about a ton of other regular and special problems create major fireground confusion. Begin to imagine you are the water, and develop the natural inclination to analyze where along the trip that water can “get stuck,” and then imagine what must be done to prevent/fix the problem.
I noticed throughout my career that a fire department will get in trouble in its community if it does not do two basic things: first, show up; second, produce water. When Mrs. Smith calls us, she expects us to actively arrive (show up!) to help her. Actively arrive means park the truck in front of her house, get off, and directly personally engage her. That is the deal we made with her. She mostly remembers the personal contact she had with her firefighters. This is where in her thank-you letter she says “nice” a lot.
The other trouble we get into is when we have hydraulic difficulties. We express our presence with water; that is what makes us different from everybody else [the pizza delivery guy doesn’t drive a 1,500-gallon-per-minute (gpm) vehicle]. If we can’t produce water, we really didn’t show up. Customers do not have a positive place in their hearts for a bunch of firefighters running around their truck screaming at each other trying to get the rig in pump gear while their kitchen fire is flashing over. We do a lot of operations that most people really don’t understand, but the average person can recognize and evaluate how the “water show” goes—or doesn’t go!
There is another category of hydraulic activity in water application beyond the nozzle. This is the “moment of truth” for the whole hydraulic exercise, because this is the point where we actually begin to fight the fire. Everything up to this point is absolutely essential and critical, but the fire really doesn’t give a hoot if we take command, grab our portable radio and thermal imaging camera, cover the street and parking lot with fire hose, or stand up a ground ladder in every other window. All these things are important, but the fire is going to burn on until there is no more fuel or when we apply enough gpm to overcome the British thermal units.
You must pay attention, remember everything you learn, and engage your senior colleagues/bosses to expand your understanding of the meeting of fire and water. Sometimes fire attack occurs so quickly and you only see it from your position, so you must capitalize on their experience and internalize both your fire attack experience at that incident and their description and more “panoramic” perception of what happened and why it happened. Never stop loading all this into your mental slide tray. Be very cautious of those who say they have learned everything there is to know about firefighting. They are one fire away from a real surprise.
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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