Summary

This manual provides information on pump operations, maintenance, troubleshooting, and the differences between single-stage and two-stage fire pumps. It covers topics such as nozzle pressure issues, throttle problems, and gear shifting. The manual also includes insights into pump modes and considerations for high-rise firefighting.

Full Transcript

# Pump Ops - **How to be a good Pump Operator (Don't just be a lever puller)** - Know your truck - take ownership - Pay attention to what the other units did. - Did they have a fire the night before? Things may not be put back because of fatigue. - Did they change over? A...

# Pump Ops - **How to be a good Pump Operator (Don't just be a lever puller)** - Know your truck - take ownership - Pay attention to what the other units did. - Did they have a fire the night before? Things may not be put back because of fatigue. - Did they change over? Are things in the right place? - Did they test hose the day before? Is the relief valve set to high? - **Ownership** - Take pride in your truck. It reflects you and your unit! - Make sure bottles are always full. 50psi is not acceptable when they can hold 55psi. - Your crew will be tired if they are on their second bottle, make sure they always have a full bottle!! - Check nozzles and hose pre-connects. Make sure nozzles are not on fog. - Check hydrant pouch. Make sure hydrant wrench and locking wrench are in the pouch and secured. - Visually check tank water-Don't rely on the water level lights - **Streets** - Take a different way into work each day - Look in the log (especially the Medic log) to see where your company is responding - Memorize the streets in your district. Don't rely on phones or MDC. Find a system that works for you and use it. - Memorize landmarks Street signs may be missing or they may be covered with snow! - Once you learn your streets then figure out the best way to get there i.e.. Fastest route, no speed bumps, narrow streets etc. - You Can't Drive With A Purpose, If You Don't Know Where You Are Going!! # **Trouble Shooting 101** ## **Cannot Achieve Proper Nozzle Pressure** - **At Pump Panel:** - Pressure relief valve set incorrectly? - Recirculation valve open? (Sutphen) - **At Engine:** - Hose not clear of bed? - Drains open? - Obstruction(debris) at discharge - **At Nozzle:** - Obstruction at nozzle, faulty nozzle - Kinks in hose ## **Throttle Will Not Work** - Air brake in cab not pulled - Throttle at panel engaged and gas pedal must be tapped in cab to override (Boise Only) - Electric throttles may become unplugged or have moisture within the harness(check and fix) ## **Pump Will Not Go Into Gear** - Low or no air to pump actuator (emergency cable pull operations) - Low voltage not allowing transmission to shift (shut down unnecessary electrical items such as lights and A/C) - Assure no steps missed, and steps were correct while putting into pump gear, - Steps correct, move truck 2-3 ft. attempt again - Still not working, shut down engine and (reboot the system) - **If pump does not work notify incident commander immediately. Start troubleshooting** # **Single-Stage vs. Two-Stage Fire Pumps: the Debate Continues** - The Columbus Fire Department has recently made the decision to begin purchasing all new engines with two-stage fire pumps. This decision has brought up two major questions: - What are the differences between a single-stage pump and a two-stage, and - in which mode should we be operating the two-stage pump? Before we attempt to answer these questions it would be helpful to discuss a brief history of fire pumps and how they have evolved. - Decades ago most fire departments used two-stage pumps in their pumpers. - Two stages were required to meet the pressure demands of the industry. - Two things happened that resulted in a shift to single-stage pumps: - The first was the shift to diesel-powered engines in the fire service. - These engines were capable of delivering much greater horsepower than that of a gasoline engine. With more horsepower being transferred to the fire pump, the pump became more powerful. - The second change that happened in the pump industry was the invention of the dual-sided pump impeller. - The impeller is the object inside the pump that is connected to the drive shaft and spins. The spinning action draws water into the pump and creates pressure. - Prior to the invention of the two-sided impeller a single-sided impeller was utilized. A single-sided impeller is only capable of pulling water into the pump from one direction. - The two-sided impeller allows the pump to draw in water from two different directions which results in a more efficient operation. - Essentially, the improved single impeller was now able to draw twice as much water into the pump housing creating greater pressure. - As a result, when you couple a powerful diesel engine to a more efficient pump design the need for the two-stage pump dwindled. - Modern single-stage pumps are capable of meeting the NFPA 1901 Standard for Automotive Fire Apparatus and are capable of meeting the demands of most fire departments across the country. - If modern single-stage pumps are capable of meeting the needs of most firefighting situations, why use a two-stage pump? - The city of Columbus, just like many other metropolitan cities, has many high-rise buildings. - The pressure requirements necessary to pump water through a standpipe system to the upper floors of these buildings is significant. - The higher pressure capabilities of a two-stage allows for the required pressures to be obtained with less work by the engine and pump. - The efficiency of the two stages allows the pump to run at a lower RPM. - A decreased pump RPM also allows the engine in the pumper to run at a lower RPM. - This decrease in demand results in less wear on the engine and also lower fuel consumption. - Another factor to consider is heat buildup. - Any time a pump is engaged it is creating heat from the spinning of the impeller. - If the impeller is allowed to spin at a slower speed, then less heat is generated. - This results in less wear on the pump housing and its components as the water in the pump will remain cooler. - The examples above are several of the advantages of a two-stage pump. # **The basic operation of a two-stage pump is very similar to that of a single stage.** - The pump goes into gear in the same manner and the throttle and valves work the same. - The major difference is the fact that a two-stage pump has two different modes in which it can operate. - The two modes are pressure and volume. - A decision must be made by the pump operator as to which mode the pump will be operated during an incident. - This is a tactical decision that should be discussed in advance with the company officer in order to avoid complications during firefighting operations. - **A two-stage pump in volume mode works essentially like a single-stage pump.** - The full volume capabilities of the pump are available as well as the pressure limitations. - Water enters both stages simultaneously, reaches the desired pressure, and then exits on the discharge side of the pump. - Sometimes volume mode is referred to as "parallel mode" as a result of the water moving through both stages at the same time, side-by-side. - **A two-stage pump in pressure mode works quite different** - In pressure mode water only enters the first stage when coming in from the intake. - That water is brought up to pressure and is then transferred into the second stage where the pressure is once again increased. - Finally the water exits into the discharge side of the pump. - Pressure mode essentially pressurizes the water twice with each stage only required to do half the work. - This mode is also referred to as "series mode." # **The flow and pressure numbers in Figure 2 are based on a 1500 GPM pump. ** - As can be seen in volume mode, 750 GPM enters both stages simultaneously and is brought up to the rated 150 PSI. - As the water leaves each stage it is combined resulting in the 1500 GPM but still at 150 PSI. - In pressure mode 750 GPM enters the first stage where it is brought up to 150 PSI. - That 750 GPM is then transferred to the second stage, where an additional 150 PSI is added for a total of 300 PSI. - In pressure mode the pump doubles the pressure but cuts the volume of water in half. # **There is no question that a two-stage pump is capable of reaching greater pressures. ** - It has also been shown that when in pressure mode, the pump runs at a lower RPM to obtain the needed pressure resulting in less wear and lower pump temperatures. - The question that then arises is which mode should the pump be run for routine firefighting? - Many argue that since less wear and tear is created in pressure mode, it is the preferred mode. - Before that decision is made the limitation of pressure mode must be addressed. # **When a two-stage pump is run in pressure mode the volume capability of the pump is 70% of the rated capacity therefore a 1500 GPM pump in pressure mode is only capable of flowing approximately 1050 GPM. ** - There are many situations during firefighting operations when 1000 GPM of water is not enough. - Below are some examples of when the demand for water would exceed the capability of a two-stage pump in pressure mode: - Multiple line operations - Quick attack operations - Deck gun operations - Ladder pipe operations - In any of the instances listed above it is possible that more than 1000 GPM would be required from the fire pump. - If the pump operator had started the initial attack with the pump in pressure mode then a mode transfer would be needed. - In order to switch the mode from pressure to volume the throttle on the pump must be dialed down. - Forgoing this step could result in a dramatic spike or drop in the pressure on the subsequent lines coming off of the pumper. - What happens if there is a crew on an attack line inside the structure when the transfer needs to take place? - Taking pressure away from them is not an option. - The only way to safely accomplish the transfer would be to pull the crew out and suffer the consequences of interrupting the fire attack. - This could have devastating effects on the outcome of the operation. - As to the argument that the pump should be run in pressure mode due to decreased wear on the vehicle, this may be overemphasized. - he diesel motors being put in today's pumpers are designed for over-the-road trucks and are capable of running for hundreds of thousands of miles before needing maintenance. No fire truck ever comes close to that work load. - Modern fire pumps are also designed for thousands of hours of operation. - The reality of the fire service is that the average pumper might have its pump engaged for a couple of hours a month. - Wear and tear certainly happens, but not to the extent that we should be basing our tactics on its prevention. # **Starting a two-stage pump in volume mode for fires not involving a high-rise eliminates the need of having to transfer modes in the middle of active firefighting operations. ** - The full volume capabilities of the pump are available. - As the adage goes "GPM's put fires out, not pressure." - The other advantage to running in volume mode as stated earlier is that the pump operates just like that of a single-stage, which most firefighters are familiar with. - The training and discipline needed to operate the pump are decreased. - The pump operator has enough things to deal with and to think about. - Eliminating the question of when the mode needs to be changed, or if it needs to be changed, allows him or her to focus on the task at hand. - Figure 3 shows a breakdown of when pressure mode and volume mode can be utilized. # **The disadvantages of using a two-stage pump in pressure mode during normal firefighting operations have been demonstrated. ** - Does this mean that pressure mode should never be utilized other than when working at a high-rise fire? - As mentioned earlier, a two-stage pump in pressure mode does allow the pumper to work at a lower RPM and cooler temperatures. - It would be beneficial for a pump operator to make the switch to pressure mode once the fire has been extinguished and overhaul operations have begun. - Commonly a single charged line is left in the structure during overhaul and while waiting on an arson investigation. - Many times this can result in the pumper being left in pump gear for an extended period. - This is an instance where slowing the pump down and decreasing the workload of the truck and lowering the temperatures would be advisable. - Pressure mode would accomplish that mission. # **In conclusion there is no question that a two-stage pump should be operated in pressure mode during high-rise operations or anytime elevation is a factor. ** - Pressure mode is also advisable after a fire has been contained and overhaul is being performed. - In all other instances volume mode should be utilized. - Volume mode gives the pump operator the full GPM output of the pump and eliminates the need to interrupt fireground operations in order to switch modes.. - As with everything in the fire service there are no absolutes.. - Engine companies should discuss pump operations and train on them. - Fire officers should size-up a scene and make adjustments as necessary. - A two-stage pump is a tool that gives firefighters more options on a fireground and can be very useful when used properly. - Be Safe. # **"Commandments" for Using the Backup Line** - With declining budgets, lower rates of volunteerism, and fewer tires, firefighters must learn to do more with less. While this trend is inevitable, and not entirely negative, it has left the fire service in the predicament of having to better train fewer people for fewer live experiences. This is not an easy task. - These conditions make it important to focus on the basics to build a framework to decipher the many variables that exist at every fire. - Many departments are instituting a "back to basics" attitude toward training. - practicing such basic skills as laying hoselines, ventilation, and search and rescue. - Many departments practice laying attack lines, yet the kills involved in laying the backup line are likely to be even rustier. - Fewer firefighters mean fewer lines. - Yet, the backup line is an essential part of any safe aggressive fire attack, and these kills should be reviewed as often as any other. - The backup line for an interior attack is laid to protect interior crews. - The first line in a building attacks the fire; the backup line may never spray water. - It is in place to ensure that all crews are able to exit the building safely. - Often, the backup line will be used only if the fire does not go well: - The attack line may run out of water, the attack crew may become surrounded by fire, or the truck crews may be cut off from their exit. - These are the types of conditions that the backup line is designed to address. - The backup line protects interior crews to ensure they are able to exit the building safely. - The backup line should be prepared for redirection, particularly to upper floors, which are often the primary exposures in multilevel buildings. - In this situation, the backup line may become the attack line, and the initial attack line may have to assume the position to protect egress. - At the least, you should have the same length of hose as the attack line. - Depending on the size of the building and where crews may be operating, you may choose to lay more. - You must not lay a backup line without doing your own size-up. - While the first officer on the scene of a fire emergency is responsible to size up the nature of the incident, once an attack line has been laid, the situation has changed dramatically. - Doors and windows have been opened to get access to the fire, and the amount of air displacement with modern fog pattern nozzles means the fire has most likely changed since the first-arriving officer announced conditions. - The officer of the backup line, while waiting for crews to obtain a continuous water source, has a great opportunity to reassess conditions. - As that officer's job is to protect the egress of working crews, he must understand where the fire is and where it is likely to go. - You must communicate with working crews and the incident commander regarding conditions. As the crew is positioning to defend the exit, you will have the opportunity to gauge how the fire is changing. - As you do your own size-up and as the fire progresses, you must communicate with the other crews and the incident commander. - If the attack line needs your help extinguishing the fire or if fire cuts off the truck crew, they will not be able to come back and ask for your help. - Hopefully, they will be able to radio for help. - You must monitor your radio in case they do. - Otherwise, moving up the attack line or up the stairs to check on the crews is a proactive way to deal with changing conditions. - Any time you are going into action, be sure to notify the incident commander, as this will dramatically change safe tacties. - You must not leave until the operating crews leave. - This rule is a no-brainer. - Since your job is to protect the exits, you cannot leave until the crews exit. - Surely, this does not mean the backup crew must be the last crew to leave the fire scene. - Once the operation is in the mop-up and wash-down phase, the backup line is not needed. - At this stage of a fire, the attack crews are not really "attacking" the fire anymore-they are engaged in putting out spot fires or smoldering debris. - Few absolutes exist in fighting fires. - Even the age-old adage "Put the wet stuff on the red stuft" no longer holds true for mitigating every tire-given the increase in and diversity of hazardous materials that may react negatively to water. - It is difficult to answer any tactical questions without the preface "It depends." - It is difficult to answer any tactical questions without the preface "It depends." - Guidelines help crews make split-second decisions during stressful situations. These 10 commandments provide a framework for training on and using the backup line in the safest and most efficient manner. - Although you do not need to follow every one at every fire, understanding them will allow you to know why you might choose to break one at a given incident. # Engine Operations -- Waterous Pump - In cab procedures - Bring apparatus to a complete stop. - Place transmission in neutral - Apply air brake - Engage pump - Road to neutral - Pause for 2 seconds - Neutral to pump - Place transmission in drive - Pump Panel Procedures - Proper PPE- helmet and gloves - Check tachometer reading - Verify pump panel "ok to pump" light is on - Open "tank to pump" valve - Place wheel chocks - Single Stage vs. Two Stage - The primary difference between a single -stage and a two-stage pump is that the former has only one impeller and no transfer valve to switch between volume and pressure operation. - A transfer valve is a two-position valve that permits the impellers in a two-stage pump to be operated in parallel (volume) or series (pressure). - Volume vs. Pressure Operation - Selection of volume versus pressure operation is determined by three factors: - Generally, the pump should be operated so that the pump gives the desired performance at the lowest engine speed. - Transfer to volume (parallel) operation for higher flows. - Transfer to pressure (series) operation when higher water pressures are required. - Pump Boss Procedures - Pressure Mode Operation - In the pressure mode of operation the PRESSURE LED is on. - The governor maintains a constant discharge pressure within system capabilities. - It adjusts the engine RPM automatically to compensate for variations in pressure. - There is maximum engine RPM programmed in the governor for pressure mode. - If the engine reaches nmed maximum RPM the message display flashes MAX RPM / OPERATOR and the engine RPM is not allowed to go higher. - The maximum engine RPM is normally set at 21.00 and is programmable.) - If the discharge pressure is below :15 PSI when the operator increases the pressure setting, the display shows PRESS LOW. - When changing from RPM to pressure mode during operations, hold the PRESSURE button for 3 seconds. - The pressure setting is the pressure that the pump was operating at in RPM mode. - Press PRESSURE button to select the pressure mode. - Result: PRESSURE LED goes on. - Press PRESET and/or rotate control knob to select pressure setting. - Result: Message display shows pressure setting, engine RPM changes. - Press IDLE button after operations to set engine to idle RPM. - Result: Message display shows IDLE ENGINE, engine at idle RPM. - Opening/Closing Discharge Valves - In pressure mode the governor maintains the pressure setting regardless of the number of discharge lines that are opened or closed providing there is sufficient water supplied. - As lines are opened the discharge pressure starts to drop and the governor raises the engine RPM to maintain the required pressure. - As lines are closed and the discharge pressure starts to rise, the governor lowers the engine RPM to maintain the required pressure. - Operating From a Pressurized Supply - When operating from a pressurized water source (hydrant, in-relay, etc.), the intake supply should be routed through a valve. - If the pressurized source fails, the pump operator can close the valve. - This eliminates the chance of sharp pressure spikes at the pump intake if the supply is resumed suddenly The operator must open this valve slowly when the supply is resumed to help prevent pressure spikes. - Running Away From Water, Low Water, or No Supply Water - There are situations during pump operations when there may be low or no supply water. This can be due to an empty water tank, a problem on the intake line, air in the pump, changing the water source, or an insufficient water supply. - The governor constantly monitors discharge pressure and compares it to engine RPM. - It is programmed to limit RPM increases when conditions arise that fall outside of normal operating parameters. - Running Away From Water: If the discharge pressure starts dropping while operating in pressure mode, the governor increases the engine RPM and attempts to maintain the selected pressure setting. If - pressure drops and an increase in RPM does not bring the pressure back up, the governor recognizes this as a running away from water condition. - RPM Limit Mode: When the RPM limit mode is in effect the PRESSURE LED stays on. - To alert the operator the RPM LED and the RPM display flash, and the message display flashes OPERATOR / RPM LIMIT. - In this mode the pressure setting does not change and the PRESET button is disabled. - When the pressure comes back up to the selected pressure setting, the RPM limit mode is canceled and the governor switches to normal operation in pressure mode at the selected pressure. - In some cases the pressure may not come back up but rernains at a level above 45 PSI. - In the RPM limit mode, the governor behaves like a manual throttle and the operator can raise or lower the engine RPM by rotating the control knob. - Low Water Cycle: If the discharge pressure is below 45 PSI, but stays above 15 PSI, the governor enters a low water cycle and the message display flashes LO WATER. - It sets the engine at 1100 RPM. - If the pressure does not rise above 45 PSI in 7 seconds, the governor sets the engine RPM at idle. - The governor repeats the low water cycle as long as the discharge pressure is between 15 and 45 PSI. - When the pressure rises above 45 PSI the governor resumes normal operation. - The values for RPIM and PSI in the low water cycle are programmable and may vary for some engine/pump combinations. - No Supply Water: If the discharge pressure is below 15 PSI, the engine RPM is set at idle and the message display flashes NO WATER. - If, within 3 minutes, the discharge pressure rises above 15 PSI the governor enters the low water cycle. - If the discharge pressure does not rise above 15 PSI within 3 minutes, the governor switches to idle mode and cancels the pressure setting. - To restart pump operations, the operator must take action (press PRESET and/or rotate control knob to select pressure setting). - RPIM Mode Operation - In the RPM mode of operation the RPM LED is on. - The governor maintains a constant engine RPM. - The pump discharge pressure can vary but, as a safety feature, the governor limits the increase in pressure to 30 PSI over the last established PSI value. - As the discharge pressure approaches this limit the governor automatically lowers the RPM to prevent a high pressure sürge. - The RPM LED blinks as the governor sets a lower RPM. - This lower RPM will be the new operating RPM setting. - When changing from pressure to RPM mode during operations, hold the RPM button for 3 seconds. - The RPM setting is the RPM that the pump was operating at in pressure mode.. - Press RPM button to select RPM mode. - Result: RPM LED goes on. - Press PRESET and/or rotate control knob to select RPM setting. - Result: Message display shows RPM setting, engine RPM changes. - Press IDLE button after operations to bring engine to idle RPM - Result: Message display shows IDLE ENGINE, engine at idle RPM. - Switching Between Operating Modes - No variation in discharge pressure or RPM occurs when changing between pressure and RPM modes. - When changing to RPM mode, the RPM setting is the RPM that the pump was operating at in pressure mode. - When changing to pressure mode the pressure setting is the pressure that the pump was operating at in RPM mode. - When the engine is at idle RPM: - Press the mode button and the governor changes modes immediately. - When the engine RPM is above idle: - Press and hold the mode button for 3 seconds and the governor changes modes. (This is to avoid ari accidental change over if the buttons get bumped.) - Pump Discharge Pressure is High at Engine Idle - Once the governor has set the engine RPM at idle, it can do no more to reduce discharge pressures. - To reduce discharge pressure the pump operator can gate incoming water, reduce pressure at the intake relief valve, gate discharges, or disable the pump. - RPM Limit with Discharge Pressure Less than 100 PSI - The level II programming code P221 sets the maximum RPM when the pump is operating with a discharge pressure less than 100 PSI. - The factory set default is for code P221 is 1500. - Access to level II programming required a password. - Contact FRC if this default limit needs to be changed. - Remote Governor Option - The remote governor option duplicates the primary governor functions. - The remote governor control module is required to be programmed as a remote (program code P303). - If error codes ES and E6 show on power up, check the programming. - Emergency Manual Pump Shift Procedures - Bring apparatus to a complete stop. - Place transmission in Neutral - Apply air brake - In cab: Engage pump (Road to Neutral) - At pump panel: pull manual shift lever - In cab: Engage pump (Neutral to Pump) - Place transmission in Drive - Attack Engine - Proper Apparatus Placement for Fire Attack - Place Pump in Gear - Set wheel chocks - Assure pump panel indicates pump in gear - Wears proper PPE - Identifies attack hose and ensures completely out of bed. - Fully opens discharge for appropriate hoseline - Throttles up to proper pressure while flowing - Communicates supply needs to second engine operator (location of hydrant) - Ensure supply line attached - If water supply from supply engine, use own tank water until tank level below 1¼ - Transition from tank to supply without spike in pressure - Adjust throttle - Consider additional hoselines - Back up line priority - Consider additional supply needs: incident escalating? - Shut tank to pump - Crack tank fill - Adjust throttle with adjustments to pump panel - Supply ladder, quick attack? - Lap around engine: look for open drains, leaks, lines needing adjustment - Critical point: failure to charge attck line - Critical point: loss of supply water - Critical point: loss of water and/or pressure on attck lines - Supply Engine - Placement: hydrant connection/ supply attack engine - Determine supply needs of attack engine - Place engine in pump gear - Wheel chock and proper PPE - Supply attack engine with 5" or 3" line and 2nd 3" if needed - Discharge pressure of 5" or 3" 80-100psi - Hydrant connection to supply engine - Inform attack engine operator when connected to hydrant - Transition from tank to hydrant without spike in pressure - Shut tank to pump - Fill the tank - Ensure discharges pressures are correct after adjustments - Communicate with attack engine additional water supply needs - Assess fire conditions and additional apparatus water supply needs - Critical point: failure to charge attck line - Critical point: loss of supply water - Critical point: loss of water and/or pressure on attck lines # Calculating Friction Loss - Standard: NFPA 1002, Standard on Fire Apparatus Driver/Operator Professional Qualifications - Indication: The Driver Operator needs to be able to calculate friction loss in fire hose in order to produce an effective fire stream. - Procedure: In the field, Palm Beach County Fire *Rescue* calculates friction loss in 3” hose by using the "Q²" method, and friction loss in 2½" hose by the " *2Q2*. Friction loss in 13½" hose is calculated by memorization. - Maximum Efficient Flow in Fire Hose - The maximum efficient flow, also referred to as critical velocity, is the maximum amount of water that can be put through a fire hose before the fire stream breaks up and becomes ineffective. - The table below lists hose sizes with the associated flows. - Keep in mind that these flows are conservative in that more water can be supplied if needed but this table should be used as a guideline. - 13/4" - 200 gpm - 21/2" - 300 gpm - 3" - 500 gpm - 5" - 1200 gpm - Friction Loss - Friction loss is pressure used to overcome resistance while forcing water through fire hose, pipes, and appliances. - To calculate the friction loss, it is necessary to know the following: - The volume or quantity of water flowing (gpm) - The size of the hose - The length of the lay - There are many ways to estimate the friction loss in fire hose. - Methods like the old hand, new hand, drop 10, and the condensed “Q” are just a few that you may have learned. - Conceivably, the most accurate method to determine friction loss is to conduct your own tests. - By doing this you will know, with almost exact certainty, the volume of water flowing at specific pressures. - Additionally, this enables us to have consistency in friction loss calculations department wide. - The attack hose (hand lines) used by PBCFR is of two sizes: 13½" and 2½". - It is manufactured by Angus called Hi-Combat, and is readily identified by the green and white stripes. - Several tests were conducted on this hose to determine the actual friction loss. - Here are the findings of those tests: - Friction Loss in 1³½" Hi-Combat Hose - (Average coefficient was determined to be: 10.8) - GPM - Friction Loss in 100' - 100 - 12 psi - 150 - 24 psi - 185 - 36 psi - 200 - 40 psi - Calculating Friction Loss in 3" Hose - An easy and accurate way of calculating friction loss is to look at the table below. - Take the 1st digit of the flow (gpm) and multiply it by the 1st digit of the next number immediately below it. - The result is friction loss per 100' of 3" hose. - For example, if the flow is 200 gpm, take 2 and multiple it by 2 (the 1st digit of the next number down the column). - The answer is 4, which is the friction loss in 100 feet of 3" hose. - Let's try a flow of 350 gpm, 3 x 4 equals 12, which is the friction loss in 100 feet of 3" hose. - This method is known as Q² or condensed Q. - (Average coefficient was determined to be: .72) - GPM - Friction Loss in 100' - 100 - 1 psi - 150 - 2 psi - 200 - 4 psi - 250 - 6 psi - 300 - 9 psi - 350 - 12 psi - 400 - 16 psi - 450 - 20 psi - 500 - 25 psi - 550 - 30 psi - 600 - 36 psi - Calculating Friction Loss in 2½" Hose - The process of calculating friction loss in 2½" hose is accomplished by figuring the friction loss as you would for 3” hose and then doubling the result. - For example, if the flow in 100 feet of 3" hose is 300 gpm, then the friction loss is 9 psi per 100'. - Next, double 9 to obtain the answer of 18 psi per 100 feet. - (Average coefficient was determined to be: 1.68) - GPM - Friction Loss in 100' - 100 - 2 psi - 150 - 4 psi - 200 - 8 psi - 250 - 12 psi - 300 - 18 psi - 350 - 24 psi - 400 - 32 psi - Appliance Loss - Friction loss in small appliances (double males, double females, reducers, wyes, and siamese) is negligible, and therefore, will not be calculated. - Add 25 psi for friction loss for the deck gun when mounted on the engine (Freightliners only) and 15 psi when used as a ground monitor. - Friction Loss in 11½" Hose - The maximum efficient flow of 1½" hose is 150 GPM. - Typically, the only apparatus that still utilizes 11½" hose is brush apparatus where friction loss is generally not an issue and therefore not calculated. - Flow of Less Than 100 GPM - NFPA requires a minimum flow of 95 GPM for a handline. - This minimum flow rate is to ensure sufficient water is flowing for Firefighter safety. - Generally, the friction loss of flows of less than 100 GPM in any size hose is negligible and therefore not calculated. # Columbus Fire Department Friction Loss Pump Chart - 1 3/4" PRE-CONNECTED HAND LINES - **Nozzle Type** - **Tip Size** - **GPM** - **FL/100'** -**NP** - **PDP/200'** - **PDP/250'** - Smooth Bore - 7/8" - 160 - 24 - 50 - 100 PSI - 110 PSI - Smooth Bore - 15/16" - 185 - 32 - 50 -

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