Tuesday, September 4, 2012

Journal Entry 19: The Smashed Tactical Box


...And Some Damn Good Advice


Ron Kanterman (September 2012)
Guest Blogger; Deputy Chief Jim Murtagh (Ret.), FDNY

My guest blogger for Journal Entry #19 is Jim Murtagh. I met Jim in 1974 when I was a freshman at John Jay College in New York City and he was an adjunct professor and company offer on the upper west side of Manhattan. Jim has been a friend, advisor, professor and mentor during my entire career and to this day, as in the last 38 years, I welcome his commentary on anything I do. This piece was a note to me, however I modified it for the reading audience so it would look more like an editorial piece.  

Jim spent 35 years in the FDNY and retired in 2000 as a Deputy Assistant Chief of Department. He rose to the rank of Deputy Chief in record time, about 12 years and was a chief officer longer then he was all other ranks put together, over his career. Not an easy feat in the FDNY. Jim is a wealth of knowledge and has taught fire operations, strategy and tactics all over the United States. He is also an accomplished author and has produced an invaluable body of work.

The following are his thoughts and comments on my last feature article “New Fire loads, New Tactics; Smashing the Tactical Box.” Once again, Jim lends his expertise and life time of experience to all of us here. Enjoy the read.

Ronnie K

Bread & Butter-Not So Fast………………….
Under the subject heading of “Bread and Butter” fires, you talked about using 2 1/2 inch lines with a smoothbore nozzle in a house, staffing permitting of course. Then you went on to talk about the fact that maybe we should look at these new residential fires as commercial fires; and that the new fires are producing more BTUs. I agree with the second half of this statement, but not the first half.

I have found in the course of my career at FDNY that a 2 1/2" hose is not appropriate for fighting interior fires in multiple dwellings, housing projects, and tenement buildings. The obvious conditions which make this size hose inappropriate is the weight of the hose when filled with water (the larger diameter making it more difficult to handle in tight spots) and the back pressure at the nozzle due to the greater flow. However what's not obvious is the difficulty moving the line into the desired location once it is charged. Once the hose begins to discharge water it requires a significant effort to control; more than the effort provided by the nozzle person, and often more than a standard nozzle team (nozzle and back up firefighter). The weight of the water and the friction resistance of the hose rubbing along the floor, around the newel posts, corners of the walls and other obstructions makes it too difficult to advance. On a safety note and even more importantly, it’s too difficult to back out (retreat) when that option is required or mandated. My personal experience as well as the experience of thousands of New York City firefighters found that 2 1/2" hose gives you greater "knockdown power" but once you are in a confined space (hallway, doorway, vestibule, etc.) it limits your ability to control and move the hose line in most directions except straight ahead. In addition, because of the weight of dry 2 1/2" hose, there will be some delay in getting the line into its first operating position. This may give the fire time to intensify and expand in to additional areas of the structure. This presents the hose team with a threefold problem; (1) working harder to get the line into position (2) difficulty or the inability to manipulate or move the hose rapidly and (3) while they are attempting to move the line, the fire is getting away from them and maybe presenting new dangers (failure of ceilings, walls, floor or other building systems). (RK-Chief Ken Scandariato, Norwich (CT) FD has said; “Remember that we don’t fight fire fight, we fight time.”) If the building is of light weight new construction, failure under moderate conditions is probable. Structural failure may be also be caused by delays in getting the line into operation or caused by the significant punch of the stream. These are real possibilities.

My career included work in highly residential areas of New York City, 1 and 2 family homes, mid-size multiple dwellings and high-rise multiple dwellings, what we all call “Bread and Butter” areas. (RK-Jim did the 5 Borough tour over his 35 years.) In 1982 I had a fire on the top floor of the six-story multiple dwelling. The fire was in the rear apartment and at that time I was the Captain of Engine 48 in the Bronx. I had four very able-bodied and very talented firefighters stretch three lengths of 1 3/4" hose followed by four lengths of 2 1/2" hose up to the apartment door. When we began to enter the apartment on the sixth floor we opened the line and got a good flow of water and then the pressure dropped significantly. The Motor Pump Operator (MPO, driver, engineer, chauffer) was well experienced and knew how to provide an adequate water supply.  I immediately notified him that we were getting inadequate water pressure and flow as I sent the “door position” firefighter down to check the line for kinks or obstructions which may have been hampering the water delivery. My MPO advised me that he was pumping approximately 150 PSI and that if I want to go higher he could but I would have to order him to do so. The firefighter I sent to get the kinks out reported back relatively quickly and told me there were no kinks in the line and that it was in good condition. I ordered the MPO go to 200 psi.  While we did get a slight improvement it was inconsequential, so I ordered the MPO to go to 250 PSI. At that pressure, we got a reasonably good stream and started to advance. As we advanced, we experienced a burst length and had to back out.  Fortunately for us, the Battalion Chief had ordered a second line onto the floor and they were able to replace us and extinguish the fire. This is, as you know, is standard operating procedure to have a backup line in position when a hose line is put into operation.

The hose that we thought had burst was brand-new and had only been delivered to us the day before.  We had put it on apparatus but did not pressure test it before we used it.  (It was not common practice to pressure test hose when it was delivered by the FDNY hose unit.) I contacted the Hose Unit, Safety Unit and Research and Development and told them about the burst length. As it turns out, it was not a burst length in the true sense and the hose did not break. The butt of the hose blew off the hose from the end where it was connected. They questioned me and asked me about the increased pressures and I told him that my studies had indicated that the hose was rated far beyond the pressures we used that and that there is no reason that the butt end of the brand-new hose should come off. They agreed and also agreed to do some research over the course of the next several weeks. I went out to the Division of Training and met with the hose manufacturers as well as officers from the Hose Unit, Safety Battalion, Research and Development and the Training Bureau.  We all examined the hose and discussed the problem and agreed we should do a test to see if we could repeat what had happened. We stretched hose and forced water through both the old hose and new hose.  We were not able to repeat what had happened at the fire, however one interesting thing did come from our research.  When we took an internal measurement of the butt and the new hose it was in fact 1 3/4"inches just as the manufacturer had said it would be and just as the purchase order said it was supposed to be. However when we measured the old 1 3/4" hose we found that the butt was 1 3/4" but the hose was found to be 1.96" in diameter. This small, slightly less than a quarter inch (21/100's of an inch) difference was significant enough to retard the flow of water and when pushed to achieve the 185 GPM flow, strong enough to overcome the power of the hose retaining ring used to hold the hose on to the butt.  The older hose (1.96") was the size we had been using and, we were accustomed to receiving its larger flow at fires. The fire department returned all the hose it had ordered and ordered new hose at 1.96 inches in diameter. (RK-A good lesson learned for all of us. Do you really know what the true diameter of your hose lines are?)

Several years later I found someone who had worked on the original research that was done in the mid-70s.  They tried to determine what size hose we could go to and get away from using 2 1/2" hose for residential firefighting. The FDNY recognized booster lines were totally inadequate and extremely dangerous in most multiple dwelling or private dwelling fires. It also recognized that 2 1/2" was totally improper for firefighting in residential occupancies. The 2 1/2" hose is appropriate for commercial occupancies and large-scale fires provided you don't have to move the hose around too often or at a rapid pace. (RK-The open floor plan in a McMansion may be one of those residential spaces a 2 ½ may work as mentioned in my article, but that may be it. Try everything first before you engage on the fire ground!)
About six months after the incident with the 1 3/4" we went to a top floor fire in a significantly large H type building with the fire on the top floor and in the cockloft. We  were the fourth engine on the assignment and the chief told me he wanted me to take a line up the outside of the building and then into the top floor. I directed my unit to stretch 2 1/2" hose not 1 3/4".  They of course objected and thought it was ridiculous. We were going straight up the fire escape and then into a vacant apartment, down the hallway  and out to the fire area. It was a relatively easy straight run. The line was pulled up the fire escape and into the apartment by four firefighters, working together to get the line in position relatively quickly.  Once we were in position I called for water and notified the Battalion Chief who was on the fire floor, that I had my line in position and was ready to attack the expanding fire. He looked at me and said "What do you think you are going to do with that?"  I told him I was going knock the ceiling down and put the fire out. To the amazement of my own firefighters and some of the other units that were working with us and who were accustomed to using only 1 ¾  lines, they saw the power of the 2 1/2" line with a  straight bore nozzle to hydraulically overhaul walls and ceilings (open up) and rapidly extinguishing the fire. However when we tried to move the line forward I had to ask the Battalion Chief for additional support. We actually used seven firefighters to effectively move the line to various areas on the top floor. The line operated just as I had expected and just as my past experience had proven. This was the right situation and we had ample and experienced firefighters to do what need to be done. (RK-It looks to me that you have to have the right people, trained and experienced and plenty of them!)

Ron, you can see by what I have written, I'm not in favor 2 1/2" hose in small homes and MD's.  I think it would be dangerous in buildings with light weight construction. However if you use a 2 1/2" hose from the outside it works GREAT; and much better than 1 3/4" which I see often in the pictures in our Fire Service Publications. (RK-Yes, even one of the masters agrees that sometimes transitional attack is the way to go. Another argument for another day, however??)

Foam….Really?
I began to read what you wrote about foam and I immediately began to think of high expansion foam and all of its pitfalls. Fortunately you did not talk about high expansion foam. Thank you! I believe it would be an absolute disaster in these kinds of lightweight buildings and would result in bigger fires and more dangerous conditions. However the low expansion foam that you're talking about seems to have a good possibility for being a solution to a growing problem. I do not have a great deal of experience with using foam as an attack line in residential occupancies. In fact I have never heard of it until you wrote about it in this article. So let me say "bravo" to your thinking out-of-the-box and your understanding and willing to try things which are not commonly thought about. I'm sure that this will be further looked into and researched and evaluated by many Fire Departments over the next several years. I sure hope it works.

Again, I reiterate that your article is excellent. It is thoughtful, different, and steps out-of-the-box - something we all need to do more often.

Best regards,

Jim

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