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broken stream fire fighting

Without this understanding, your knowledge base about your nozzle would essentially equal that of a civilian.Nozzle Considerations & TestingWhen selecting a nozzle, make sure you fully understand its capabilities with your current system. There certainly is a place for both and if you find yourself only taking a stand on one of the two nozzles, chances are you are uninformed. Some have been around a long time, some are better versions of their original design, and some have come on the market in just the past decade.The most important element for firefighters to remember with regard to nozzles is that the nozzle is your primary weapon. Blockchain + AI + Crypto Economics Are We Creating a Code Tsunami? A master stream is a large volume of water in which more than 300 gallons per minute is discharged. Solid bore or solid tip nozzles can be effectively used for foam application with: Production of an adequate amount of bubbles to form an effective foam blanket is the definition of: Which is true with regard to the use of fog streams on an interior fire attack: Firefighting foam solution is____percent water. Drastically changes conditions and heat conditions increase significantly. A(n) ___________ nozzle will discharge a wide range of flows with an effective fire stream, depending on the pressure being supplied to the nozzle. Again, watch video and it clearly demonstrates why we should not be using fog patterns. ", where xx.x stands for the calculated quantities rounded to the Essentials of Fire Fighting Smooth-boreThe smooth-bore nozzle, which has been around for many years, could be considered the staple of the American fire service.

Describe types of nozzle control valves. Cool superheated gases at the ceiling. Watch: Detroit (MI) Firefighters Dig Out Firefighter Trapped in House Fire Pattern must be broken by nozzle movement to increase heat absorption, Variable stream (straight, narrow fog or wide fog), Low-pressure versions produce less nozzle reaction, less engine wear, Costs less than other versions (variable gpm and automatic), Moving parts inside nozzle, which may lead to mechanical failure, water deposit build-up changing operation, High-pressure versions can have poor flow at low pressure, Larger, bulkier and heavier than smooth-bore counterpart, Will shut off or may not open at low nozzle pressures, Minimal back pressure or reaction force, Larger, bulkier and heavier than smooth bore counterparts. Most smooth-bore nozzles are designed to operate at a nozzle pressure of _______ psi. A stream of water, or other extinguishing agent, after it leaves the fire hose and nozzle until it reaches the desired point", Define Fire Stream. Standardize stream selection for interior structure firefighting. One drawback is that unless the water pattern is broken up, the water from a smooth-bore wont absorb as much heat as its broken or fog-stream counterparts.Pros: Fixed-gpm/Variable Stream/Constant FlowThis type of nozzle will produce the predetermined gpm when supplied with the required nozzle pressure. Discuss the extinguishing properties of water. Which is the most common type of foam proportioner used in the fire service: The most effective type of foam for use on polar solvents is: Alcohol resistant/aqueous film forming foam (AFFF), Petroleum-based fuels are____and float on water. Sometimes, a simple comparison of flows with a gpm gauge is all you need.Things to RememberTest your own nozzles with a properly calibrated gpm meter and your pump and hose systems on a regular basis. Now customize the name of a clipboard to store your clips. It should be moved aggressively all over the room, hitting the floor, sweeping the upper atmosphere, using the ceiling and walls to break up the stream into small droplets. Typically, the smooth-bore nozzle produces the greatest reach/gpm combination of all nozzles while at the same time using the lowest engine pump pressures.The smooth-bore will also maintain the same water pattern to reach the seat of the fire, keeping the pattern compact and getting large amounts of water at the seat of the fire. If you dont agree or understand, go flow test one and you will see. Which standpipe system relies solely on the fire department connection to supply the water and is dry when not in use. A_____nozzle is used with a foam solution to produce a low expansion, short lasting foam. Solid Stream: Stream formed by a smooth bore nozzle. Be the courageous follower in your department and challenges all perspectives to find out what works best for your demographics. 3. Dont use 100 psi fog nozzles. The recommended nozzle handling techniques for directing the stream are important for the nozzle firefighter to know and understand: Hold the nozzle, at an arms length, from the bail. When making foam, in order for the nozzle and educator to work properly: Are recommended for use with protein and fluoroprotein foams. Close minded firemenWe have always done it this wayand no one got hurt.or just put the damn fire out mentality, prevents progress. Free access to premium services like Tuneln, Mubi and more. Binder #2

What are the ways that water can extinguish fire? This design makes it ideal for combat firefighting. During the time a stream of water passes through space, it is influenced by velocity, __________, wind, and friction with air. Activate your 30 day free trialto unlock unlimited reading. The velocity field of a flow is given by $ec{V}=k\left(x^{2}-y^{2} ight) ec{i}-2 k x y ec{j}$ where k is a constant. Simple in design.less that will go wrong, and that IS a big deal when the shit hits the fan. fema unprepared

Simply put, you get what the manufacturer says youll get at the required nozzle pressure, similar to its smooth-bore counterpart.Years ago, these nozzles only came in 100-psi versions, but now you can find them with common nozzle pressures of 50, 75 or 100 psi. Most of the time when a broken stream is used, it is to make a water curtain of protection. 5. Please copy and paste this embed script to where you want to embed.

The key is determining which nozzle is right for your needs. The minimum size hoseline used to make an offensive attack on a single room and content fire is: Aqueoius film forming foam (AFFF) is used in_____percent, AFFF can be utilized on hydrocarbon fire at_____percent proportions, Which is a method by which foam acts as a suppression agent, If there is adequate ventilation, steam from a water fog will_____toxic gases present, To produce the proper rate of foam on flammable liquids fire, a_____is neccessay, Before placing a foam line in service using an in-line proportioner, Select the proper foam concentrate for the burning fuel involved, For application of aqueous film-forming foam, educator or proportioners operate on a ______principle. After doing a little research, we determined that many of our automatic nozzles were old and hadnt received annual calibration maintenance as prescribed by the manufacturer. Please help us to share our service with your friends. Minimize thermal balance disruption. 6th Edition 2 \left[ \begin{array} { | } { \left( x _ { 1 } - x _ { 2 } \right) } { \left( y _ { 1 } - y _ { 2 } \right) } \\ { \left( x _ { 2 } - x _ { 3 } \right) \left( y _ { 2 } - y _ { 3 } \right) } \end{array} \right] \left[ \begin{array} { l } { C _ { x } } \\ { C _ { y } } \end{array} \right] = \left[ \begin{array} { c } { \left( x _ { 1 } ^ { 2 } + y _ { 1 } ^ { 2 } \right) - \left( x _ { 2 } ^ { 2 } + y _ { 2 } ^ { 2 } \right) } \\ { \left( x _ { 2 } ^ { 2 } + y _ { 2 } ^ { 2 } \right) - \left( x _ { 3 } ^ { 2 } + y _ { 3 } ^ { 2 } \right) } \end{array} \right] The SlideShare family just got bigger. List checks that should be included in nozzle inspections. If youre struggling with your assignments like me, check out www.HelpWriting.net . Hand-lines are usually 1-1/2 inch hose to 2- inch hose. To achieve extinguishment, sufficient water must be applied to: Absorb heat faster than it it being generated. Again, see the video when the fog pattern is opened twice. They are different animals, so to speak, and therefore must be fully understood by their users.Pros, Broken or Aspirated StreamThe broken or aspirated stream nozzle provides great mobility and excellent gpm flow at low nozzle pressures. Broken Stream: Stream formed by a smooth bore nozzle when the bail is partially closed. Activate your 30 day free trialto continue reading. If you have formulated an opinion on this but it is not based on your own research, training, experience, and education, I would encourage you to re-evaluate your position on this subject. We also use the term fog nozzle to describe the type nozzle we use to make a fog stream. Cellar distributor nozzles are designed to be used to fight localized fires in basements where firefighters cannot make a direct attack. Use larger diameter hose or multiple lines. JavaScript isn't enabled in your browser, so this file can't be opened. A stream of water, or other extinguishing agent, after it leaves the fire hose and nozzle until it reaches the desired point. Remember to do this while in an attack position from the ground, not while standing up. POLICY & PROCEDURE. Just google the history of the fog nozzle and pattern and how they were originally designed to be used or read up on Lt. Andy Fredricks, then come back and finish reading my boring rant. What units are used to measure pressure in the SI system? (Skill Sheet 14-I-2), 12. Chapter 16 Fire Streams. Define friction loss, elevation loss/gain, and water hammer. $$ Fire Detection, Alarm, and Suppression Systems, Vocational Training at IOCL, Panipat ( Mechanical Department) Report. 2. T/F In a rack-and-pinion steering system, the rack is the steering input and drives the pinion in order to move the wheels (48). Broken fire streams are also used when fighting a basement fire or when fighting a fire in a partition. When preparing to enter the fire area the nozzle firefighter shall ensure that when a combination fog/straight stream nozzle is being used, it is in the straight stream position (barrel rotated all the way to the right). Automatic Nozzles are dangerous, period. overhaul. Whether its a nozzle youve had for 15 years or a new nozzle someone is trying to sell you, put the nozzle on your standard hose load and, with a digital gpm gauge, perform flow testing to ensure you get adequate water. When operated on a fog pattern, you can move almost as much air as a PPV, essentially creating a wind fueled fire. The next stream most fire fighters call a fog stream but it can also be called a spray stream. A particular hazard of the ________ stream, when used for interior firefighting, is that it can actually force super-heated gases and air into unburned areas. Water being discharged from a nozzle under pressure producing a force on the nozzle operator is called: Standard nozzle pressure for a solid-stream, master-stream device is considered to be _______ psi. Fire stream types are generally classified as: A stream discharging more than 350 gpm is known as a(n) ________ stream. bumblebee Compare the stagnation pressures at the inlet and the exit. SB nozzles are extremely effective interior weapons and have been since the inception of the American Fire Service. Further increase in nozzle pressure will only increase. 8 5 0 F I R E M E N, https://www.facebook.com/354871098828/videos/10153373103318829/, Dennis LeGear Ahead of the time at the OFD Daryl Liggins, Jay Comella, Jim Edwards and I plus othersCITY OF OAKLAND The automatic nozzle may produce what appears to be a penetrating stream with extended reach; however, at lower nozzle pressures, this stream may produce well below 100 gpm.We found that many older automatic nozzles generally require higher nozzle pressures to deliver water in sufficient quantities for an interior attack. In todays fire service, there are a multitude of nozzles available to firefighters that are capable of delivering various stream types and fire flows. Water is used to extinguish fires more than any other agent because it: Has the ability to absorb tremendous quantities of heat. And, they are just plain durable and an effective weapon. A straight stream is discharged from a/an __________ nozzle. Challenge the Status Quo! A fire stream is defined in terms of the size of volume of water. Moral of this point, NEVER operate any type of fog pattern, no matter how narrow the fog pattern, when combating interior fires (when fire suppression, not to be confused with mop up). Operate a solid-stream nozzle. A stream of water, or other extinguishing agent, after it leaves the fire hose and nozzle until it reaches the desired point", Share & Embed "Define Fire Stream. Submitted: October 2, 2004, FIRE STREAMS FOR INTERIOR OPERATIONS Allows water to penetrate dense material instead of running off surfaces. 1. Conditions that warrant the use of water fog or broken stream while operating on the interior of a structure: After extinguishment, a water fog or broken stream may be directed out a window in the fire area to assist with removal of heat and smoke. What is the difference between a solid stream and a fog stream? If we allow firefighters to use a SB line when they have never used one before but we dont train them on how to use it, then we shouldnt get pissed if they have a negative experience and decide it is not a viable option. High Rise Operations Conference 2022 (HROC), CFT Fire School: Leadership & Tactics Conference 2022, 2022 Conference Membership Club (CFT 100), High Rise Operations Conference 2021 (HROC), 2021 Conference Membership Club (CFT 100), Apr 21 | Pensacola Bch FL Command & Control 4/12/2021 Agenda Posted, Apr 21 | Pensacola Bch FL Gallons Per Second 4/23, On The Road Event & Seminar Registration 2022, Command & Control Success: Below 2,000: Saving Lives, Civilian Lives, Command & Control Success: Command Post Location, Command & Control Success: People Before Water, Command & Control Success: All-Hands Depth on the Bench, Command & Control Success: Tactics Put Out Fires, Command Success taught by Chief Isakson, Online Webinars from CFTactics Instructors. OISD-STD-117 Fire Protection Facilities for Petroleum Depots, Terminals, Pipe Is codes for 3844 internal fire hydrants and hose, ACO-5 Use of Handlines, Turrets, and other Appliances, 184648009 new-hot-bitumen-storage-tank-construction-guidelines-march-2012-2, Cb gf web in aug 2016, controls r2 8.23.16 final, CATALOG OF BRAVE TRAINING SOLUTIONS TRAINING PRESENTATIONS, Be A Great Product Leader (Amplify, Oct 2019), Trillion Dollar Coach Book (Bill Campbell). Minimize fire, heat and steam pushed into uninvolved areas of the building. APIdays Paris 2019 - Innovation @ scale, APIs as Digital Factories' New Machi Mammalian Brain Chemistry Explains Everything. through the three points by solving the following simultaneous equations: It shall be the policy of the Oakland Fire Department to use a straight or solid stream when engaged in an interior structure fire. 1. The Fire Captain has to make these split-second decisions quickly but also be mindful of himself and his crew. )When using any nozzle to extinguish a fire, keep in mind that actual flow may be affected by many variables, such as differences in piping from the pump to the discharge point, increasing friction loss, variances in hose types and their individual friction loss, kinks in the hose, different pump pressures, water supply issues and debris passing through the water system. Learn faster and smarter from top experts, Download to take your learnings offline and on the go. Department Goes Digital with Accessing Critical Building Information When Responding to Emergencies, Old School vs. New School: The Generational Divide, Sprinkler System Types and Impact on Building Fires, Five Things To Do BEFORE the First Five Minutes, Prepared vs. Ready: Fundamental Differences for Firefighters, 30-Car Pileup Involving Tractor Trailers and Bus Snarled I-81 in PA, Exploding Liquid Oxygen Tanks Shut Down Seattle (WA) Highways, Tampa (FL) Firefighters Win Raises; 18.5% Over Three Years. stream fog fighting fire quizlet straight narrow wide mma patterns nozzle broken The nozzle features an internal spring mechanism thats pre-set at the factory, which provides a pretty constant nozzle pressure at varying gpm.Two main issues with automatic nozzles: 1) theyll shut off at low pressure and 2) they seem to always provide what appears to be an adequate stream even when gpm is low. Thats right, not just your job, but ALL OF US. In addition, it does provide the firefighter with a little more versatility to use during overhaul and hydraulic ventilation if needed. The drawbacks when compared to smooth-bore or variable-stream nozzles: reach and penetration.Pros. Other broken streams are produced by different types of nozzles such as foam nozzles, cellar nozzles, and directing two streams together in midair; reflecting a stream off a wall or by flat spoon-bill nozzles. fire nozzle te handline series mafco solid inquiry specification info stream combination hose Small incipient stage fires confined to mattress, stuffed chair, wastebaskets etc. See our Privacy Policy and User Agreement for details. Firefighter I Application rate in relationship to a flammable liquids fire is: Amount of foam or foam solution needed to extinguish a fire, That part of total pressure is lost while water moves through a hose line. 9. They have low nozzle pressure (50 psi), typically open orifices the pass debris (essential for stand pipe operations) and solid packed streams that will penetrate objects such as dry wall much better than their fog counterparts. Hand-line streams are those used when men are fighting fire. As such, its extremely important that you care for it properly; it should be taken care of in the same manner that a soldier would care for their weapon. Suppose that f(t) = f1(t) f2(t), where f1(t) = cos 0t, f2(t) = 1, -/2 < t < /2; f2(t) = 0, elsewhere. Observe how violent the conditions get. Prevent flashover by cooling upper levels of the fire area. They operate by: During an attack on a confined interior building fire, if a fog stream is applied incorrectly, it can upset the: Fine water droplets and maximum high water surface area are characteristics of a _________ stream. 2. a) Use convolution in the frequency domain to find F(). Water is the primary fire extinguishing agent because of its: The thermal energy that is absorbed when a substance is converted from a solid to a liquid or from a liquid to a gas, both called a change in state, is known as: To reduce pressure loss due to friction, what should be attempted?

These were big in the 80s and 90s, but fortunately are phasing out of interior firefighting. Many firefighters loose site of a simplistic concept they teach us in rookie school. Nozzles that flow more than 300 gallons per minute are not recommended for hand-lines. Another commonality between these nozzles and the smooth-bore: You can get more water with more nozzle pressure, but youll also experience more nozzle reaction. Often, people dont care what they use, so they use whats provided to them under the parameters that theyre given and dont spend too much time looking into how to make their flow better or all thats available.The bottom line: No one can tell you what to use. What are the three size classifications of fire streams? We dont know what we dont know, until we know we dont know. I now know it was wrong and dangerous.

Which foam application technique is used when the others are not feasible: Which foam application technique requires the stream to be broken to prevent splashing: Regarding the application of firefighting foam, the major difference between hydrocarbon and polar solvent fuels is that: Foams in use currently are of the mechanical type and must be____ and ______before they can be used. See our User Agreement and Privacy Policy. The biggest problem I see when debating these nozzles is that many firefighters are just simply uninformed or under educated on the advantages and disadvantages of BOTH nozzles and even at times, dont know how to operate the nozzle properly so that it is an effective weapon. This nozzle is also good for use with foam applications, as it self-aspirates the foam at the tip. A _________ stream is one in which the pattern is separated into coarsely divided droplets. At 212*F, a cubic foot of water expands to approximately ________ times its original volume when converted into steam. Staying in your own bubble (not getting out of your own department to see how the rest of the world does business) prevents progress. Hoses that are 2-1/2 inch can discharge 125-300 gallons per minute. Ive learned this through training, education, and experience of being steamed burned (multiple times). Operate a broken-stream nozzle. To keep our site running, we need your help to cover our server cost (about $500/m), a small donation will help us a lot. Our advice is to flow test your current nozzles and try to get as much water as possible while taking into consideration reaction force and maneuverability.

Enable and reload. Lastly, remember that the nozzle doesnt matter if water never makes it to the tip, but some nozzles perform far better at low pressure and flow than others. Firefighters must know what operating pressure their nozzles require and how the nozzles can be adjusted during operation. Air enters a diffuser with a velocity of 600 ft/s, a static pressure of 10 lbf/in.2, and a temperature of 20 F. The velocity leaving the diffuser is 200 ft/s, and the static pressure at the diffuser exit is 11.7 lbf/in.2. (T or O pattern works well) The deflected water will: Reduce steam burn injuries to firefighters and occupants. The ironic thing is, this is what I was taught in 1989 in rookie school. It is also his job to decide what type of stream should be used in the fire attack. The only way to truly know what youre getting with a nozzle is to do formalized testing. the following format: "The coordinates of the center are (xx.x, xx.x) and the b) What happens to F() as the width of f2(t) increases so that f(t) includes more and more cycles on f1(t)? As the main body of fire is knocked the angle of the stream can be lowered and directed at the burning solid fuels. Its larger than other nozzles and aspirates the stream as it travels through the tip, producing large water droplets to better absorb heat. SlideShare uses cookies to improve functionality and performance, and to provide you with relevant advertising.

$$ I believe in having versatility on an engine and by having both options, only make sense. You should have a thorough understanding of its operation, maintenance requirements, downfalls, safety concerns, flow rates, reaction forces and any special features.

A water curtain forms the shape of a fan or curtain to protect and shield firefighters from a really hot fire or combustible materials. Its time to but this debate to bed. and the radius of a circle that passes through three given points. Straight Stream: Narrowest stream formed by a fog nozzle. Main reason a fog stream has greater heat-absorbing capacity than a solid stream is its: A stream designed to be as compact as possible with little shower or spray is known as a ________ stream. The most common version of this nozzle, the Vindicator, is made by First Strike Technologies. to find the coordinates of the center of the circle ( Cx, Cy) that passes AI and Machine Learning Demystified by Carol Smith at Midwest UX 2017, Pew Research Center's Internet & American Life Project, Harry Surden - Artificial Intelligence and Law Overview, Pinot: Realtime Distributed OLAP datastore, How to Become a Thought Leader in Your Niche, UX, ethnography and possibilities: for Libraries, Museums and Archives, Winners and Losers - All the (Russian) President's Men, No public clipboards found for this slide, Autonomy: The Quest to Build the Driverless CarAnd How It Will Reshape Our World, Bezonomics: How Amazon Is Changing Our Lives and What the World's Best Companies Are Learning from It, So You Want to Start a Podcast: Finding Your Voice, Telling Your Story, and Building a Community That Will Listen, The Future Is Faster Than You Think: How Converging Technologies Are Transforming Business, Industries, and Our Lives, SAM: One Robot, a Dozen Engineers, and the Race to Revolutionize the Way We Build, Talk to Me: How Voice Computing Will Transform the Way We Live, Work, and Think, Everybody Lies: Big Data, New Data, and What the Internet Can Tell Us About Who We Really Are, Life After Google: The Fall of Big Data and the Rise of the Blockchain Economy, Live Work Work Work Die: A Journey into the Savage Heart of Silicon Valley, Future Presence: How Virtual Reality Is Changing Human Connection, Intimacy, and the Limits of Ordinary Life, From Gutenberg to Google: The History of Our Future, Full Out: Lessons in Life and Leadership from America's Favorite Coach, We Should All Be Millionaires: A Womans Guide to Earning More, Building Wealth, and Gaining Economic Power, Authentic: A Memoir by the Founder of Vans, Believe IT: How to Go from Underestimated to Unstoppable, Second Nature: Scenes from a World Remade, Test Gods: Virgin Galactic and the Making of a Modern Astronaut, A Brief History of Motion: From the Wheel, to the Car, to What Comes Next, The Metaverse: And How It Will Revolutionize Everything, An Ugly Truth: Inside Facebooks Battle for Domination, System Error: Where Big Tech Went Wrong and How We Can Reboot, The Wires of War: Technology and the Global Struggle for Power, The Quiet Zone: Unraveling the Mystery of a Town Suspended in Silence. If you continue browsing the site, you agree to the use of cookies on this website. FIRE DEPARTMENT interior stream policy put in place the same time all NP was reduced to 50psi with 160gpm and 260gpm our target handline flows (Steve Kerber, Aaron Fields, Ray McCormack FYI looking fwd to the air entrainment part of the interior study), Policy & Procedure # A small fire stream is considered to be a volume of stream less than 40 gallons per minute. A broken fire stream is when a solid stream is broken up into fine drops of water for protecting exposed buildings. Clipping is a handy way to collect important slides you want to go back to later. A solid-stream nozzle is made to produce a compacted stream of water. 1. If a fog nozzle was used, adjust the nozzle to a fog pattern. After completing this lesson, the student shall be able to effectively operate a solid stream nozzle, fog stream nozzle, and broken stream nozzle following the policies and procedures set forth by the authority having jurisdiction (AHJ). Each nozzle has its pros and cons; selection can vary geographically. Best Fog nozzle weapons are the 50 psi nozzle pressure nozzles. Watch the video and see what type of protection it provides. (Skill Sheet 14-I-1), 11. Ensure you clean and maintain your nozzles as outlined in the manufacturers directions to ensure proper operation and use. The biggest mistake I have seen in my career for those who have not been exposed to SB nozzle operations (and thats a lot of departments in suburban America), is the lack of understanding on how to operate this weapon in an effective mode. We also found that the nozzle wont operate or could even shut off at low nozzle pressure without warning.In addition, automatic nozzles must be pumped appropriately and used as they are designed in order to get the desired gpm. Smoldering material i.e. Dont think so?? Determine the static temperature at the diffuser exit and the diffuser efficiency. In reference to a fire stream, friction loss is defined as: That part of the pressure that is used to overcome friction in the hose. So, the point of this rant..BOTH ARE AWESOME WEAPONS THAT SHOULD BE USED. Why? The Science of Time Travel: The Secrets Behind Time Machines, Time Loops, Alternate Realities, and More! Applying water or foam directly onto burning material to reduce its temperature, Applying water or foam over an open fire to reduce the temperature so firefighters can advance handlines, Dispersing hot smoke and fire gases from a heated area, Creating a water curtain to protect firefighters and property from heat, Creating a barrier between a fuel and a fire by covering the fuel with a foam blanket, Smothering by diluting or excluding oxygen, When heated to boiling point, water absorbs heat, Visible form of steam is called condensed steam, Effective extinguishment with water generally requires steam production, Water absorbs more heat when converted to steam than when heated to boiling point, Readily available, relatively inexpensive, Has greater heat-absorbing capacity than most other common agents, Water changing to steam requires large amount of heat, That part of total pressure lost while forcing water through pipes, fittings, fire hose, and adapters, When water flows through hose, couplings, appliances, its molecules rub against insides, producing friction, Loss of pressure in hoseline between pumper and nozzle is most common example, Affected by velocity of water and characteristics of hose layouts, Generally, the smaller the hose diameter and longer the hose lay, the higher the friction loss at a given pressure, flow volume, Hose diameter too small for volume needed, Pressure loss When nozzle is above fire pump, Pressure gain When nozzle is below pump, When flow of water through fire hose or pipe is suddenly stopped, shock wave produced when moving water reaches end of hose and bounces back, Pressure surge referred to as water hammer, Sudden change in direction creates excessive pressures that can cause damage to water mains, plumbing, fire hose, hydrants, fire pumps, To prevent when water flowing, close components slowly, Rate of discharge measured in gallons per minute (gpm) or liters per minute (L/min), Volume discharged determined by design of nozzle, pressure at nozzle, To be effective, stream must deliver volume of water sufficient to absorb heat faster than it is being generated, Type of fire stream indicates specific pattern/shape of water stream, Velocity of stream a result of nozzle pressure, Nozzle pressure, size of discharge opening determine flow, Characteristics of effective fire streams, May maintain better interior visibility than others, Operate at reduced nozzle pressures per gallon (liter) than others, Less likely to disturb normal thermal layering of heat, gases during interior structural attacks, Produce less steam conversion than fog nozzles, Do not allow for different stream pattern selections, Provide less heat absorption per gallon (liter) delivered than others, Hoselines more easily kinked at corners, obstructions, Fine spray composed of tiny water droplets, Design of most fog nozzles permits adjustment of tip to produce different stream patterns, Water droplets formed to expose maximum water surface for heat absorption, Desired performance of fog stream nozzles judged by amount of heat that fog stream absorbs and rate by which the water is converted into steam/vapor, Nozzles permit settings of straight stream, narrow-angle fog, and wide-angle fog, Nozzles should be operated at designed nozzle pressure, Several factors affect reach of fog stream, Interaction of these factors on fog stream results in fire stream with less reach than that of straight or solid stream, Shorter reach makes fog streams less useful for outside, defensive fire fighting operations, Two types of nozzles control rate of water flow through fog nozzle, Combination nozzles designed to operate at different pressures, Designated operating pressure for most combination nozzles is 100 psi (700 kPa), Nozzles with other designated operating pressures available, Setbacks of nozzles with lower operating pressures, Discharge pattern can be adjusted for situation, Reduce heat by exposing maximum water surface for heat absorption, Wide fog pattern provides protection to firefighters, Do not have as much reach/penetrating power as solid streams, May push air into fire area, intensifying the fire, One that has been broken into coarsely divided drops, While solid stream may become broken stream past point of breakover, true broken stream takes on that form as it leaves nozzle, Absorb more heat per gallon (liter) than solid stream, Have greater reach, penetration than fog stream, Can be effective on fires in confined spaces, May have sufficient continuity to conduct electricity, Differing designs cause each one to handle somewhat differently when operated at recommended pressure, Those with variable patterns may handle differently in different settings, The water pattern produced by nozzle may affect ease of operation, Nozzles not always easy to control at/above standard operating pressures, When water flows from nozzle, reaction equally strong in opposite direction, thus a force pushes back on person handling hoseline, Reaction caused by velocity, flow rate, discharge pattern of stream, Reaction can make nozzle difficult to handle, Increasing nozzle discharge pressure, flow rate increases nozzle reaction, When water is discharged at angles from center line of nozzle, reaction forces may counterbalance each other, reduce nozzle reaction, Balancing of forces is why a nozzle set on wide-angle fog handles more easily than straight-stream pattern, Enable operator to start, stop, or reduce flow of water while maintaining effective control of nozzle, Allow nozzles to open slowly so operator can adjust as nozzle reaction increases, Also allow nozzles to be closed slowly to prevent water hammer, Provides effective control during nozzle operation with minimum effort, Ball, perforated by smooth waterway, is suspended from both sides of nozzle body and seals against seat, Ball can be rotated up to 90 degrees by moving valve handle backward to open and forward to close, Nozzle will operate in any position between fully closed, fully open, Operating nozzle with valve in fully open position gives maximum flow, performance, Cylindrical slide valve control seats movable cylinder against shaped cone to turn off flow of water, Flow increases/decreases as shutoff handle is moved to change position of sliding cylinder relative to cone, Stainless steel slide valve controls flow of water through nozzle without creating turbulence, Pressure control compensates for increase/decrease in flow by moving baffle to develop proper tip size, pressure, Consists of exterior barrel guided by screw that moves it forward/backward, rotating around interior barrel, Major difference between rotary control and other valves is they also control discharge pattern of stream, Swivel gasket for damage or wear; replace worn or missing gaskets, Pistol grip (if applicable) is secured to the nozzle.

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