You have the Brunacinis, the Mittendorfs and the Brannigans. They all have their words of wisdom on the summaries of their teachings. They’re words to live by. Words of wisdom are not only a tribute to these great fire service educators and all of their hard work and experience, it also provides an excellent guideline to study and learn from.
Well now it’s my turn. Big Paulie’s words of wisdom on movin’ the big water. Are you ready? Here it goes.
Rule #1- Big Paulie says, tradition and pride can be hazardous to your health.
Ah yes, tradition and pride. It’s what makes the fire service go round. It’s fun, it promotes camaraderie and it’s easy. What do I mean by easy? Listen to these statements and tell me if they sound familiar.
We’ve always done it this way and the fires have always gone out.
We are an aggressive fire department, we go in and attack the fire.
Fire departments that make exterior attacks are known as “foundation savers”, they’re a bunch of wimps.
Smooth bore tip nozzles are the only ones that work.
Automatic nozzles are the only ones that work.
This one is my favorite: We don’t get those kind of fires here (large ones).
The list goes on an on. I’m sure all of you have your favorites. If you analyze each of these statements, you can find one common denominator, it’s easy. You don’t have to change anything, there are no studies or evaluations to do and there is no risk taking to endure, you just do the same thing over and over again. Well, guess what, the times they are a’changing. Take a look at the history of the fire service. We’ve gone from horse drawn wagons to motorized apparatus, we’ve traded in our buckets for hose. We’ve gone from no air packs sucking in all the life destroying particles to using air packs. And of course, we’ve gone from 2-1/2” supply lines to large diameter hose. I would like to have been a fly on the firehouse wall when some of these changes were made, or for that matter just suggested. Are you starting to get the picture here?
Big Paulie’s one recommendation is to please keep an open mind. Tradition and pride are a very important part of the fire service, but please don’t let it get in the way of making our job easier and more important – safe.
Rule #2- Keep it simple, dude.
Fire fighting definitely gets high marks as far as degree of difficulty is concerned both mentally and physically. Let’s face it – we are dealing with an abnormal situation that we did not create and did not get any say so in when and where it would happen. Therefore, I feel it is extremely important to make our job as easy to perform as possible. What does this mean when it comes to flowing big water? Let’s take a look.
• Get rid of the formulas
We have all been taught the formulas for calculating the required fire flow for a structure fire. First of all, who says that one person’s approximation of what the dimensions of a structure are is going to be the same, or even close, to what mine or the next guy’s is? Second, how sharp are you going to be in your estimation at 2:00 AM when you are first in and the whole world is on fire? If you are like most of us, things could be a little cloudy. Instead of using this formula, why not break fire flows down into three categories: small, medium and large.
Small fires can be, for lack of better words, the junk fire flows that require small amounts of water to extinguish (50 GPM works good). You know these types of fires, small trash and brush fires or possibly a smoldering under the hood vehicle fire. It’s the ones that we pull the booster line on.
Medium fires are for the most part the interior compartmentized structure fires where an interior attack will be attempted. Flows of 120-150 GPM seem to work well on these.
Finally, large fires are basically just that – the big one. They can be large structures where both exterior and/or interior are fully involved, large vehicle fires, etc. Basically, it’s anything that requires more than your standard small diameter handline to extinguish rapidly. What kind of flows are we looking at? As much as possible based on water supply, manpower and equipment. I would not hesitate one bit to hit a fully involved two car garage with a 1000 GPM stream from a deck gun under the right circumstances. The bottom line is – hit the fire with as much water as you can development based on the circumstances that are presented.
• Calculating Engine Pressures
Oh no, not more formulas! Yes, it’s called fireground hydraulics. There’s books written on this stuff, in fact, there are even college courses on it. Okay here’s the scenario. This time we’ll make it easier. It’s 12:00 noon, you’re first in on a ripper. The guys are screaming for water. The first evolution deployed is at least 200 feet of 3” hose wyed off to a manifold with two 1-3/4” handlines and one 2-1/2” handline. The requested flows are as follows: 1-3/4” 150 GPM each
2-1/2” 250 GPM
Now quickly, what is your engine pressure? Come on, hurry up, we need the water! We’re getting clobbered here!
I think hydraulic formulas have no place on the fireground. They are too difficult and require all of the figures to use. What if you don’t know how much hose is on the ground? The formulas will not work. One of my favorite formulas that I really get a kick out of is the one for relay pumping. You’re asked to establish an engine pressure for the source pumper based on the size and length of the hose and flow requirements. True fact – in a relay pump operation, which could be long, the amount of hose is usually not known. Sometimes it takes two or more units to complete the lay. How about the flows? Most of the time the actual flow is not known until the evolution is completely set up and engine pressures are established.
Come on you guys, let’s keep it simple. Pump charts can and should be used to develop all engine pressures. Pump charts are reference charts that have pre-calculated pressures to work with for any hose evolution your department will ever have to perform. The more exact engine pressures that can be listed, the better. For example, pre-connected handlines, fixed master streams, foam operations, sprinkler operations, high rise building fire protection systems and relay pumping.
For some of the make or break evolutions, basic math should be all that is ever needed. A listing of statistics will help this process, such as, the friction loss per 50 feet of hose for all sizes, nozzle pressures, master stream appliance friction losses, elevation gain or loss, etc.
To make a long story short always be looking for the easiest, most simple way to do a task. Can the current method be done at 2:00 o’clock in the morning, under a lot of stress and/or with minimum manpower? If not, then it’s time to reevaluate and find an easier way.
Rule #3- The water’s out there, you just gotta go get it!
How many times have you heard the excuse of a poor water supply as the reason given for losing a building to fire? I get a kick out of watching the evening news telling about a major fire where everything was lost and the interview with the fire chief put the blame on a poor water supply. What’s really funny about this when you look in the background is that you see large diameter hose on the ground and the fire building is in the middle of a major city. Major cities and even normal size cities for the most part have hydrants available for miles. How then does the water supply problem occur? What usually happens on big fires is the closest hydrants to the fire building itself are connected to supply lines. Why? Because they’re the easiest ones to get to. As the fire gets bigger, the water supply in the immediate area of the fire building gets diminished. This is where most departments, especially the ones using large diameter hose, give up and say we are out of water. If we can’t get it with 5” then there isn’t anymore. In reality, they are not really out of water within their means of obtaining more. “The water’s out there, you just gotta go get it.” Long distance relay supply line operations and water shuttle operations are two ways to obtain more water.
Preplanning of your high fire flow potential areas in conjunction with taking a good look at what your department’s equipment can produce for a big flow operation is essential for developing a plan for the big one.
Now don’t get me wrong, there are situations where true water supply problems exist. However, before throwing in the towel, look at all your options, you never know you might come up with a solution.
Rule #4- Don’t screw around, just blast it!
Elephant hunting with a BB gun, that’s what I like to call an attack on a big fire with a low flow stream. There’s a basic rule of thumb given to us by mother nature, which says it takes so much water to put out so much fire. Plain and simple! If the amount of water isn’t enough to put out the size of fire you’re dealing with, guess what, the fire won’t go out, at least quickly.
There are formulas that tell us how much water is needed for a specific size building. This is good for books, but not good for practical application. The bottom line is – hit the fire with as much water as possible based on your manpower, equipment and water supply situation with an attempt to overwhelm the fire. If 250 GPM will knock a fire down fairly quickly, then 500 GPM will be even faster.
Let’s take a look at a very common scenario that most cities deal with, a mobile home fire. Let’s say that we’ve got a full assignment responding to a mobile home fire. The first in engine company has laid a 5” supply line from the hydrant 300 feet away. They have 500 gallons immediately available from their booster tank and are faced with two immediately threatened exposures, one on each side of the fully involved mobile home. What usually happens is that the crew will pull pre-connected handlines to cover the exposures until the water supply can be established. The key here is to protect exposures while conserving the water from the booster tank. With two lines out you know as well as I do, there is a chance of draining that 500 gallon booster tank before the supply line is charged. And guess what, the fire that was creating the exposure problem is still there and probably burning with more intensity and now we’re out of water. Have we conserved water, or wasted it?
Let’s use the same scenario again but change the initial attack. We’re still going to lay the supply line but this time instead of pulling the pre-connects, we’re going to get on top of the engine, swing that deck gun around and blast the fire building with everything we’ve got (most booster tank operations can produce only 500 GPM), and knock the snot out of the fire. If we don’t knock it completely down, there’s a real good chance that we will turn it into a lazy type fire that is going nowhere instead of a raging inferno. This should take only 15-20 seconds. At a 500 GPM rate, a 20 second blast will use only 166 gallons of water. The above mentioned operation is known as a Blitz attack.
Rule #5- The only thing too much water will do is put the fire out faster.
Question – If it takes 30 seconds for a 200 GPM stream to extinguish a fire in a building, then will a 500 GPM stream take more or less time to extinguish the same fire? The answer is obviously less time. This is simple stuff. Don’t be afraid to throw as much water as possible in the given situation to put the fire out. The key to this operation is to overwhelm a fire stopping it as quickly as possible and then shutting the stream down. If done correctly, there is a real good chance the fire will be extinguished faster and with less water.
Rule #6- It’s easier to design a pumper to flow large volumes of water and not need it than it is to flow large volumes of water from a pumper not capable of doing it.
All pumpers should be designed for flowing large volumes of water. This involves big pumps, large plumbing, large master stream appliances, multiple large intakes and large diameter hose. The larger, the better. What this does is decrease the friction loss in all parts of the water delivery system which decreases the horsepower needed from the engine of the pumper. All this makes for a more efficient operation. The chances for doubling a pump’s capacity with a unit designed for big flows is extremely possible. It will easily handle the small flow needs as well.
Now let’s turn it around. How easy will it be for a unit designed with standard plumbing, appliances and hose to push the big water?
Rule #7- Pump it up!
Here is another one of those mother nature rules again. Water moving through fire hose, nozzles and discharge plumbing requires a positive pressure. High flowing and hard hitting streams can require higher than normal engine pressures to produce. We in the fire service can sometimes be paranoid of these higher pressures for fear of equipment failure and potential accidents. Well not to worry! The manufacturers of all of our fine equipment also have that fear. That is why they have designed their equipment to withstand the pressures needed for the big water operations. Take a look at this list of statistics,
All water passage components within the fire pump system of a fire apparatus have to be able to withstand 600 psi.
Most small diameter handline type hose today comes with a 400 psi service test pressure. According to NFPA standards, this pressure needs to be 10% higher than maximum operating pressure. That gives us a maximum working pressure of 360 psi.
Manufacturers of master stream appliances have given us a maximum working pressure ranging from 175 to 200 psi depending on the make of the appliance.
Now keep in mind that when these pressures were established, the guys making this stuff knew that fire fighters would be using it and could possibly mess up and over pump it, so a safety factor was built in. The above mentioned equipment can actually withstand more than the maximum pressures they have given.
So what does all this mean? 1-3/4” handlines can produce 300 GPM streams, 2-1/2” and 3” handlines can produce 600 to 800 GPM streams and smooth bore tips on master stream appliances can operate at nozzle pressures reaching 175 psi capable of producing killer streams.
Rule #8- Unless it’s written by the manufacturer, it can be challenged!
Training in the fire service is provided by hand me down information from fire service textbooks, fire department SOPs and fire department instructors. The fire service as with the rest of the world, is ever changing. We need to be able to adapt to these changes and sometimes improve or change the way we do things. For some reason the fire service, when it comes to water delivery, tends not to want to change as is evident by some of the stuff that is out there. We need to take a hard look at how we currently do things and see if there is a need for improvement. Don’t be afraid to invent new procedures and techniques that may enable us to do our jobs better. Just because it’s not written yet, doesn’t mean it can’t be done. Don’t be afraid to be the pioneer. The only limiting factors in our quest for improvement should be the manufacturers guidelines that are established on the equipment that is being used.