Hose and nozzles for effective operations
“Planning a Hose and Nozzle System for Effective Operations” by Jay Comella (April 2003) provided some interesting insight and information. However, I don’t agree with two statements in particular.
The first point is the author’s statement that automatic nozzles require more training by firefighters. I have been using both smooth bore and automatic nozzles since the mid-1970s and have had little to no problems with the automatics. I generally like their performance because they allow us to deliver varied flows and pressures at the nozzle. Today’s automatic nozzles have greatly improved over those we used years ago. Automatic nozzles are quite simple to use because all the motor pump operator has to do is run the pump up to a predetermined SOP pressure and leave it alone. Firefighters on the knob can then operate the valve to achieve whatever flow they need (or can handle), and the automatic nozzle makes whatever water volume they select to be delivered effectively more than just a nice stream of water. Automatic nozzles make sense because they put the control of the fire flow in the hands of the firefighter, where it belongs, not in the hands of the pump operator, who, in many cases, cannot see the fire or conditions.
The second point is in regard to the reference to the One Meridian Plaza Fire in Philadelphia. I have been a fire command and tactics instructor for several years, specifically focused on the subject of the things that can go wrong at fires. Sadly, as the facts have shown, the Philadelphia Fire Department (PFD) experienced several examples, all in one incident—not unlike many of us. Fortunately, senior-level friends and colleagues in the PFD have learned much from that fire and have aggressively shared that information with the rest of the fire service so we can learn from them—a commendable action that many departments, unfortunately, still choose not to do.
From my understanding of the fire and after speaking directly with several senior- level PFD chiefs, it is not accurate to say that the nozzles contributed to the death of the three firefighters or the loss of the building. Simply put, the nozzles had nothing at all to do with the tragic deaths of the three firefighters (whose job was to ventilate the towers) or the loss. The author’s focusing on the “nozzles” being the problem inappropriately takes the focus from the real issues and could cause significant “deterred confusion” for less-experienced readers of Fire Engineering, resulting in misinformation.
Nozzles, like most of the tools we use to fight fires, require objective research, understanding, and training by the users. No one “tool” is the answer to many situations we encounter on the fireground. Fire officers and firefighters need to consider all the options with an open mind to ensure they have the absolute best chance to return home after the run … and it starts and ends with training.
Billy Goldfeder, EFO
Battalion Chief
Loveland-Symmes (OH) Fire Department
Certainly there is no argument with many of the points that Jay Comella makes. In particular, the fact that fire departments are not flowing what they think they are flowing has been a problem for a long time. Also, his comment that if water is not being delivered above the critical flow rate, the fire is NOT being extinguished is exactly on target. Some of his conclusions and solutions, however, are not in line with progressive thinking and in some cases are based on inaccurate information.
The article praises police departments in their efforts to increase their firepower by moving from revolvers to automatic weapons. Yet, just a paragraph away, Comella suggests that for the fire service, fog nozzles or automatic nozzles are too complex to be used. Is he saying that somehow a fire nozzle performing its job is more important than that of a police officer’s weapon? Clearly, the automatic pistol is more complex but just as clearly has been made reliable enough for officers to trust their life to it. Fire nozzles and, in particular, automatic fire nozzles have passed the same tests of time. A properly designed spring is one of the most reliable mechanisms known to man; everyone’s daily life literally depends on thousands of springs performing their job. To give up the extra capability of the fog nozzle/automatic nozzle is a huge step backward for the fire service.
Over time a myth has developed in the fire service about the reasons for the development of the automatic nozzle. Some people believe that it was to make “pretty streams”; this is absolutely not true. Automatic nozzles were developed to make more effective streams. Clyde McMillan noticed that, in spite of the fact that stacked tips were made to adjust for varying flow rates on the fireground, seldom if ever was anything but the smallest tip used. The smallest tip was carried in place to make sure that when the stream was first started sufficient pressure could be developed. The consequence of this strategy was that in the many cases where more water was available, it was never delivered because it required shutting down the stream to find out. An automatic nozzle will adjust immediately to whatever water can be gotten to it at whatever pressure the nozzle is set for. What McMillan found was that with automatic nozzles, he consistently delivered more water on the fire than what was possible before the automatic nozzle.
Another comment frequently made is that automatic nozzles require more training. Again, this is absolutely the opposite of what is the actual case. With anything but an automatic nozzle, the pump pressure must be calculated to achieve the correct nozzle pressure. With automatic nozzles, all that is required is to run the pump up to a pressure considered the maximum acceptable for the quality of the fire hose in use; then the nozzle operator can select any flow that he can handle safely based on footing, posture, and a host of other considerations.
Automatic nozzles are available in all pressures from 50 psi up through 100 psi. If the pump pressure is set to deliver X gallons per minute at 50 psi out of a smooth bore and a 50-psi automatic is substituted, it will flow the exact same X amount. The kind of nozzle does not change the friction loss in the hose. How this myth originated is that frequently a 100-psi fog nozzle is compared with a 50-psi smooth bore with the pump pressures identical. Well, clearly in this case, the smooth bore will flow more, as it has 50 psi more friction loss to use to achieve this flow.
If we are going to compare, let’s compare with equal nozzle pressures. The first Task Force Tips (TFT) automatic handline nozzles were designed specifically for the Syracuse (NY) Fire Department when it faced serious staffing and financial issues. The goal was to remain as effective with 13 engine companies as the department had been with 18. Members realized that with 13/4-inch hose and an automatic nozzle, they could attack with very high flow rates of 200 to 220 gpm and then allow the firefighter at the end of the line to determine what flow was required by using a nozzle that could be throttled with the shutoff. By throttling with the shutoff and keeping the pressure correct with the automatic nozzle, the nozzle operator has TOTAL control over the hoseline. The real problem is that, over the years, fire departments using automatic nozzles have allowed their pump pressures to slide down to very low numbers because the streams looked good. The solution is NOT to abandon the technology but to bring the pump pressures back up to where the manufacturers recommend so that the nozzles function as designed.
Another myth of the fire service is that high pressure on hose causes it to become stiff. The hose manufacturers have not been sleeping for the past 30 years, either. They have developed new weaves and new materials that do not behave as hose did in the past. I am familiar with high-combat hose in particular, and I know that I have amazed many people by bending the hose tightly around their waist in a very small loop. They are most amazed when they discover that the pressure is set to 250 psi! Please do not assume what seems obvious: run the pressure up and see how it behaves. The problems with low pressure and kinking can be far more severe than the problems of high pressure and bending.
My final point concerns Comella’s reference to the One Meridian Plaza Fire in Philadelphia. His statement “The tragic loss of these members was caused in no small part by poor weapons selection” is in total contradiction to all testimony presented by all levels of the Philadelphia Fire Department from the commissioner on down. The Plaza fire was the ultimate example of Murphy’s Law: delayed alarm, two floors connected by an open stairwell, open framed offices in the process of being finished, an opening into the power raceway that took out both primary power feeds to the building while first-arriving crews were going up in the elevator—causing them to be trapped, backup generator systems that did not function, pressure-reducing valves on fire department connections set incorrectly at 40 psi, steel doors chained shut from the inside, and a host of other problems. The nozzles are not even mentioned as a primary cause; the pressure relief valves’ having been set wrong are listed as primary, with the result being that the nozzle streams were ineffective. The entire official report on this tragic fire is available at http://www.interfire. org/res_file/pdf/Tr-049.pdf. I implore readers to take the time to read this report so that they have the facts of what happened. It is a gross misstatement of the facts to explain the deaths of three firefighters by a simple statement regarding the selection of nozzles.
Fire departments all over the world are using fog nozzles to fight high-rise fires on a daily basis. To use the One Meridian Plaza fire as an example of why smooth bores are somehow superior is simply inaccurate.
The evolution of the fire nozzle is very clear. First came smooth bores, then fixed fog, followed by selectable fog, and then automatic fog nozzles. The latest advancements have been in dual-pressure and low-pressure automatic fog nozzles. Each of these evolved as the technology and capabilities evolved to solve the operational problems of past designs. Each fire department needs to ask the following: Were all of these advances in technology wrong and ill-advised? Does it really make sense to jump back 150 years of development? If so, somebody needs to tell the police department to adopt muzzle loaders; after all, they were smooth bores, too!
Stewart G. McMillan
President
Task Force Tips, Inc.
Jay Comella’s argument for replacing 11/2-inch handlines with 13/4-inch handlines for interior firefighting in an effort to increase target flows from 125 gpm to 150 gpm and higher was presented in a logical manner, and his arguments may have appeared convincing to a minority. His discussion concerning friction loss, nozzle reaction, and achievable flows from various hose and nozzle configurations confirmed much of what we already know (or should know) about tactical options in relation to handline flow rates. However, his reasoned approach became blatantly flawed by a total belief in one type of nozzle, a smooth bore. “It is the only kind of nozzle that should be taken into the most hostile work environment on the face of the earth—the interior of a burning building,” he says.
There are literally volumes of learned scientific research that clearly demonstrate the physics associated with water-fog patterns in cooling the overhead, and this research is supported by much practical experience. Why is it that authors such as Comella repeatedly fail to address such research in their “call to arm”? The combination nozzle is used by three-quarters of the world’s firefighters—they can’t all be wrong!
The reasons Comella gives to oppose fog nozzles demonstrate a complete lack of awareness—or a misunderstanding—of “new-wave,” “pulsing” fog applications used to counter fireground hazards associated with flashover, backdraft, and smoke explosions. These innovative approaches are based on original Swedish concepts and have evolved throughout parts of Europe, Australia, and the United States since 1984. It is no coincidence that those who have adopted these water-fog application techniques have never lost another firefighter to the various forms of extreme fire behavior in 19 years! As a firefighter, I have advanced high-flow smooth bore handlines into burning South Bronx, New York, tenements during the 1970s and have compared this experience with that of combination nozzles’ offering the versatility of straight stream/fog patterns in London tenement fires during the 1970s-1980s. Over a 30-year career, I have come to the logical conclusion: The combination nozzle offers the best of both worlds!
Paul Grimwood
www.firetactics.com
Jay Comella’s article had many important tips for engine company operations. However, some key points were omitted, and others were misleading. Years ago, the dangers of surge pressure with smooth bore nozzles, especially when using several water lines, were cited as a safety hazard. The automatic nozzle was introduced to help prevent firefighter injuries. Many fire departments had staffing levels drastically reduced, and lighter hose became a practical way to reduce back strains. Along with safety, effectiveness was evaluated. The bulk of a community’s fire problem was in dwellings or apartments. Both are small compartments, and the practice of using 13/4-inch hose and automatic nozzles became standard. Fire service leaders failed to realize that large open spaces still existed in many other occupancies. Economics and budgets drifted toward equipment geared to the “greatest potential” for fire. Therefore, the emphasis shifted to a lighter and more automatic system for hoseline and nozzles.
His article contained an error in the review of the deadly One Meridian Plaza high-rise fire. The crew that perished was assigned to the Ventilation Group. Their deaths were related to becoming lost and not giving an accurate description of their location. The lesson learned from these line-of- duty deaths is to know your reference point at all times and be able to communicate it!
Another fact from the Meridian Plaza fire is that the 92-foot 2 240-foot open office space was unsprinklered, which was critical to fire growth. Comella also failed to mention that convenience stairs connected the 21st and 22nd floors, which had a sizable effect on the rapid spread and extinguishments efforts. Comella failed to cite time, distance, and flow limitations of a six-inch standpipe. Without a doubt, ventilation, system malfunction, and human limitations had an impact on the strategy at Meridian Plaza. It is estimated that approximately 6,000 gpm were needed for containment of one floor. This “target flow rate” would be impossible in an offensive posture with any size mobile handline.
William Shouldis
Deputy Chief
Philadelphia (PA) Fire Department
Jay Comella’s article was well researched and presented factual and detailed information. It presented excellent comparisons on nozzle selection, friction losses, water flow, and options to consider for improving operations in different types of buildings. As a supporter of smooth bore nozzles, 21/2-inch hose, and improvements in the fire service that help firefighters do their job more efficiently and safely, I thought the article was very helpful to the fire service. It presents many facts and ideas that will help us think about positive changes. In addition, it allows for excellent discussions in classroom settings for those of us involved in the training of young or prospective firefighters.
Jim Connors
Captain, Engine 5
San Francisco (CA) Fire Department
Jay Comella’s article was one of the best articles written for engine company operations. It was well researched and easy to read. Even though he had to use his own department as an example, he is straight and to the point. We can and should learn from these common and (in Oakland’s case) devastating tactical errors. This scenario is a nationwide problem. Many departments still insist on using 13/4-inch hose with combination nozzles (untested) for commercial fires or standpipe operations. How many more firefighters do we have to kill before we change our tactics and tools?
Mark Wesseldine
Rockland County (NY)
Fire Training Center
Injury and Death Rates
In reference to “Reducing the Firefighter Injury and Death Rates, Part 2” (Roundtable, February 2003), I am disappointed in the manner in which the research was conducted. Chief John “Skip” Coleman’s statistics are misleading to readers who assume (as most do) that polls are given to populations large enough to produce accurate results. If the reader had skipped the first paragraph of the article, the statistics may have caused outrage and shock over the lack of preventative measures to reduce firefighter risk, “[Stations that] provide firefighter survival training: 9%.” Out of fire stations all over the nation, only 9% provide survival training? As a firefighter with a vast knowledge of the operations of many surrounding stations, I can assuredly say that many more than 9% of the stations train their firefighters in survival methods. However, the first paragraph states the polled population that the second paragraph fails to, “Here are the answers from 21 respondents.” Twenty-one respondents? There are more than 240,000 firefighters (not including volunteers) in the United States alone. Of those 240,000, only 21 were polled. Comparing one number with another, I am certain that I am not the only one who would find something sketchy about those statistics.
It is true, yes, that preventative measures to reduce the risk of injury to firefighters could be improved. We are constantly looking for new ways to help prevent injury to those who risk their lives to protect others. However, using inaccurate statistics to prove your point does exactly the opposite. It reduces your credibility. In the future, please be sure to include only accurate statistics and polls in the articles. I am well interested in finding new ways to reduce health risks for firefighters, but convincing readers with unreliable information is not the way to do so.
Seth Bowie
Firefighter
Hyattsville Volunteer Fire Department
Prince George’s County, Maryland
Skip Coleman responds: I must apologize for any confusion that Bowie refers to. There was no “research” conducted in the preparation for the article. As I stated in the article ” … I thought it might be interesting to provide some statistical information compiled from combined responses to the question. Here are the answers from the 21 respondents.”
I wonder if he read the previous month’s article or this article in its entirety. Had he done so, he might have realized that no “poll” was conducted. No survey was sent out to any part of the “firefighter population.” Instead, as usual, I asked a question of the 10 or so Roundtable panel members along with any interested firefighter who got the question from FireEngineering.com. I believe we are “data-ed” to death (literally). If I simply wanted to provide “research” and statistical facts and figures concerning this issue, there are a host of reports and articles that provide such information that I could have reprinted or taken information from. Those reports and articles have been there for years. They are published every year, and we still “allow” firefighters to die in fires. It’s time we did something other than publish statistics. We know it happens, now what are we going to do about it?
I’m not sure where Bowie gets “that only 9% of the stations” did anything. I never said anything about “stations.” I did state that 9% of the persons who gave me three ways to finally reduce firefighters deaths believed that deaths would be reduced by providing survival training to firefighters.
Jay Comella’s article was refreshing and had some interesting points; however, it would be irresponsible if we didn’t ask a few questions and raise a few points. It is exciting that someone is willing to begin critically assessing the attack handline system and its components. Unfortunately, there is little mention of the primary purpose of this system, which is fire suppression.
There are two well-known nozzles in the fire service, the smooth bore or solid stream and the combination nozzle, which may be a basic spray, constant gallonage, automatic, or constant/select gallonage. This is not a complete list, however, and the article only anecdotally examines three nozzles.
As the late Chief Peter Ganci (FDNY chief of department) once asked me and Chief Al Turi (retired FDNY chief of safety), “Are people so naïve to think that in the past 100 years we couldn’t come up with a better nozzle?” There are many other types and brands of nozzles to examine. It is our responsibility to check out all the technology available. Most importantly, if the goal of a department is to establish a hose and nozzle system for effective operations, we should be clear as to what are effective operations.
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The purpose of a nozzle/hose/pump system is to achieve fire suppression. The National Fire Protection Association (NFPA) National Fire Protection Handbook defines fire suppression/extinguishment as follows: “Extinguishment can be achieved by cooling the gaseous combustion zone or the solid or liquid combustible.” Furthermore, according to the NFPA, the application rate and type of stream determine the speed of suppression with water. The rate of application is commonly referred to as gallons per minute (gpm). The type of stream refers to heat absorption. The two common ways of increasing a stream’s heat absorption is by breaking the stream into smaller droplets and increasing the number of droplets by increasing your gpm. “To be effective, the water droplet must be formed near the base of the fire or be large enough to have sufficient energy to reach the seat of the fire despite air resistance, the force of gravity, and the fire thermal column. When droplets are too small, they can be deflected by the fire plume or be evaporated before they reach the base of the fire.”
Simply put, we want a system that creates an “August thunderstorm,” “heavy drops of water,” a system that is measured not based on assumptions. We want a system that is reliable and manageable. The flow rate must be consistent and based on modern fire behavior requiring high flows. The experienced firefighter knows mobility and high flows get the job done. Any system can deliver water, but mobility is the key to getting the job done. The author is correct: Simplicity is a really good thing.
To begin with, the system is not just composed of the hose and nozzle. One cannot forget the pumping system and its part in the apparatus. The article presented a basic view of an advanced basics problem. To ignore the pump is a critical mistake—one easily made by many when first evaluating fire streams. We could write a separate article on apparatus plumbing nightmares, but here is a simple example and something you should check: What is the internal plumbing friction loss (IPFL)? We know that the term “FL” should apply to all the aspects of water movement, but it appears evident to us that this term is only being applied to FL in hose, with total disregard for the plumbing, appliances, and so on, thus the need to single out each element of FL.
What is the difference in pressure between what is registered on the pump panel gauge and the pressure at the discharge? Look at photos 1 and 2: The pressure sensors are located after the first valve. How many 90-degree bends are in the plumbing before it hits the discharge? The pressure sensors should be located no more than four inches away from the discharge; however, unless you specify this, they will be put after the first valve. What is the friction loss created by this bad plumbing? It must be measured, or you just don’t know. Doing the evaluation is easy: Place a pressure gauge on the discharge, and flow your target flows to record the difference between the panel gauge and the discharge. This will give you your IPFL. Is it not uncommon to see 15 to 35 psi of IPFL from bad plumbing. It is very common for pumpers to have significant FL in the plumbing. To date, the most we have seen is more than 100 psi of IPFL for a flow of 300 gpm.
Comella notes in his summary of the Board of Inquiry findings regarding the line-of-duty death of Tracy Toomey that the findings were based on the “assumption” that the department’s target flow rate of 124 gpm through 11/2-inch hose was met. It is not uncommon for theoretical flow rate assumptions to be made. It is important to the fire service that these assumptions stop being made not only during firefighter line-of-duty death investigations but, more importantly, before companies make stretches into hostile fire environments. We must stop making assumptions about how much water we are delivering.
Comella makes an assumption of 38 psi of FL in 11/2-inch hose, yet he fails to specify how that number was obtained. It is accurate from a theoretical calculation, and then we have a chart on page 68. All those numbers are only relevant to the actual hose used to produce those numbers. Measured results are sure to be different on your hose and will vary based on age of hose, brand, and types of couplings used. If it was obtained by measuring this 38 psi of FL, it is only relevant to the hose that Comella was using and specifically the very hose in the tests, not the brand or type but the actual hose he was using.
Reference to this fact is made in NFPA 1961, Standard on Fire Hose, A.5.1.: “… Friction loss varies considerably depending on the construction and design of the hose, the roughness of the lining, and its internal diameter, which may be different for different grades of hose. The types of couplings can also affect the friction loss.” It is simple and important to measure this friction loss by using in-line pressure gauges, a smooth bore nozzle, and a pitot gauge or a calibrated flowmeter. This process is also explained in NFPA 1961.
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Photo 3 shows how different hose linings can be. All hose is not created the same. There is some really good stuff and some really bad. If you live by low bid, you’re getting what you paid for. The NFPA service test for hose will tell the hose won’t burst and the coupling won’t slip, which is comforting if you are using your hose like an airbag. If you are using it to deliver water, you are interested in the friction loss. Photo 4 shows some hose that had obvious delamination. The liner had completely separated from the jacket. However, it passed the service test also commonly referred to as the pressure test. It won’t flow squat, but it passed the test.
Depending on the type of nozzle you’re using, your stream may look good, but the application rate is not there. Many have blamed this on certain nozzles. We cannot blame anyone but ourselves. The problem is that most of us don’t know what we’re flowing because the items being discussed are not being tested on a large scale or being taught at the major fire academies. You must examine your hose for excessive friction loss by conducting flow tests.
Awareness of the friction loss differences in hose requires flow tests of your engine company attack stretches to be measured by using flow- meters and line pressure gauges. This should be done annually on all preconnects and any routine stretch the company encounters. The flow charts for all companies reflect the measured flows the companies need for the conditions they face on arrival. The equipment you will need includes a flowmeter, pressure gauge, and pitot. I recommend you use only a paddle- wheel style that you can calibrate using a pitot and a smooth bore.
Advanced basics: Throw out all those “hose friction loss charts” except when teaching theory, and then be very clear that theory is based on perfect uniform conditions. You must measure everything! This is not a perfect world.
We must evaluate all our hose because all hose is different, even from the same manufacturers. All plumbing is different unless you have specified sensor locations and identical plumbing configurations. Advanced basics: There is not going to be one pressure you mandate for your target flows. Every pumper requires its own unit-specific flow chart rechecked every year and every time you replace or change hose. We do not want “inaccurate pump charts.”
The statement by Comella that his department’s target flow rate was “most likely” based on 1918 testing is an assumption. The 125 flow rate may have pertained to the primary attack line. Reference to NFPA 1410 recommends 100 gpm minimum on the primary and 200 gpm minimum on the backup line for 300 gpm total. It is unfair and disrespectful to the current and prior Oakland operational command staff to print assumptions when we just don’t know. Maybe this only references the department’s first line.
Comella is incorrect regarding hoseline handling characteristics. The FL in a hose and the pump discharge pressure have nothing to do with hoseline handling characteristics. Handling characteristics of a hoseline are based on two types of reaction force—hoseline reaction (HLR) and nozzle reaction (NR). As he stated, RF is based on flow and pressure. The FL in the hose has no bearing on RF, nor does the EDP. A higher FL hose simply means you need more EDP to get the desired flow and pressure. If the flow and pressure at the nozzle are the same, then the person on that line has the same handling characteristics as another line being supplied with a higher EDP.
As for nozzle reaction, the only way to determine this is, again, to measure it. Firefighter Paul Stein and his brother Captain (Ret.) Mike Stein, currently director of R&D for the Fire Department of New York, designed the best machine for this purpose. It measures the reaction and takes the “feels like” stuff out of our results. (See photo 5.)
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Comella is partially correct in his statement, “If hose size remains constant and flow is increased, pump discharge pressure must be increased to account for greater friction loss.” This would be based on the “assumption” you are using the same nozzle. You can increase flow simply by having a lower pressure nozzle with no change in EDP. The lower NP will account for the greater friction loss.
His desire to flow 150 to 180 gpm can be done with 11/2-inch hose with acceptable EDP (200 psi or less), provided the right nozzle is used. So to state that we must use 13/4-inch hose to get these flows is incorrect. Although we agree we should use the larger hose, to imply you can’t get the flow desired is irresponsible. Comella’s opinion seems to be based on “assumptions” regarding FL charts commonly used in the fire service. This conclusion is made based on using those very formulas to confirm his numbers.
The target flow of 150 to 180 is, again, based on what science? If you want to cool fire gases, flow water to create the heavy August rain. Go for maximum heat absorption. Flow the maximum manageable flows capable of using the technology available. The Albuquerque (NM) Fire Department targets 250 gpm on our 13/4-inch residential lines and 325 gpm on our 21/2-inch commercial lines. We use the best pump, hose, and nozzle system we could find after working with FDNY and Lewisville, Texas, and others doing nozzle, hose, and pump tests. We went for the August rain heat-absorbing, high-flow, low-reaction system.
Comella seems to focus on size of lines and tips instead of volumes of water. If 262+ gpm from a 21/2-inch line is the goal, why would you not use a 13/4-inch with the right nozzle and flow the same amount, yet have much greater handling characteristics? It is not the size that matters; it’s the flow and how you use it!
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He lists nozzles available today but fails to mention several other nozzles available. He also fails to inform the reader that solid streams, with a lower surface-area-to-volume ratio, do not have as good heat-transfer characteristics as spray nozzles and, consequently, are not as effective in absorbing heat. They are also a better conductor of electricity. (See NFPA Fire Protection Handbook, 17th Edition.)
All departments for years have been conducting nozzle testing; FDNY has done extensive testing, looking at many critical aspects of the nozzle’s primary purpose. It uses the 15/16-inch smooth bore as the weapon of choice. However, it still tests everything and takes its time. Current tests on one nozzle are in their third year. FDNY tests for things like heat absorption and cooling of ceiling gases, using thermocouplings and controlled burns. The department uses experienced nozzlemen and research and development people. When they finish a test, they do it again. They publish their work and send it through the chain of command. (See photo 6 of FDNY in burn tests checking ceiling cooling.)
The statement concerning automatic fog nozzles, specifically their being “most susceptible to failure,” is totally unfounded based on the information he provided. Show us the studies and the data to support that claim. If there are none, then the remark is an assumption.
Research needs to be done scientifically and methodically. The data then need to be subjected to field testing to confirm or reassess the results. Testing is boring and time-consuming unless you are really passionate.
Robert Halton
Deputy Chief
Albuquerque (NM) Fire Department
Editor’s note
In “Fireground Size-Up: Row Frames,” by Michael A. Terpak (May 2003), on page 88 under the heading “HEIGHT,” the first sentence should read “With building heights well within reach of fire department ladders, the use of fire department ladders to gain access to the roof is a viable option when accessibility is not a problem and you do not need them to remove building occupants.”
