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sr71

Akron Brass Saberjet Nozzles

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An exellent thread!

I would like to add one additional job related issue with fog nozzles and standpipe operations. In older apartment buildings with standpipes, we have found (through testing) that in some buildings, above certain floors heights, it was impossible to get the required psi that a fog nozzle requires. That was the reason we have smooth bore nozzles on our standpipe packs.

I understand that that pressure can/will be supplemented when the next arriving engine connects to the FDC. The problem is the time between the first arriving engine company operating off the standpipe system, and the arriving engine connecting to the FDC. It would be great to have the FD feeding the FDC prior to engine companies utilizing the standpipe system, but that isn't reality in my department.

Another issue that comes to mind is debris in a standpipe system. Debris in a fog nozzle can drastically effect the GPM and stream. A smooth bore nozzle is less apt to clog.

As for the debate between smooth bore and fog nozzles, it will go on forever. Is firefighter training an issue...yes, but that dosen't solve the psi issue in our older standpipe systems, only equipment will.

Welcome home, LarryALB

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Good post John.

This thread has been awesome. Some of the comments I totally agree and some I respect very much from who its coming from. But there are a few things I want to point out from my experience, training and level of personal and professional knowledge. I don't see anything here posted that couldn't be attributed as "fact" based on some article, book or other medium.

2) You have taken away my fog pattern protection (good example look at the propane xmas tree evolution) you only die once

Good point, but I for one and don't recall seeing anyone else say that every preconnect on an apparatus should have a smooth bore nozzle on it. Even if that was the case how long does it take to put a fog nozzle on it if you need it. I nkow that I have at least one on my engine on the trashline. Furthermore the xmas tree evolution is one of the very few times that I can find that I ever needed fog pattern protection and as someone stated even that has risks. Particulary with fog nozzles in regard to "fingering" that occurs."

3) Most of our fires are room and contents. (How big are these spaces normally)use the fire formular to know how much water you need.

You need as much water as you need. While I am also an advocate of using the fire flow formula, NFPA still states that the minimum target flow of hand lines for interior structural firefighting is 150 gpm. So even if the fire flow is 40 gpm, your hand line should be receiving at a minimum 150 gpm. This scenario comes down to good fire stream management not hydraulics.

4) How much wet stuff do you need to put the red stuff out.

Again I just want to point out that it takes as much as it takes. Minimum flows are minimum flows and that is what should be targeted. The pump operator cannot see inside the building to know its a room and content, he should just ensure that he as the proper PDP for the proper flow. Fire stream management. I want to overwhelm the fire and ensure I am absorbing the BTU's faster then the combustion process can give them off.

8) I'm not sure how long ago, either at Montour Falls or Emmittsburg, task force tips put on a class on the use of fog nozzles. One thing that was pointed out was about 14 to 18 inches away from the nozzle, in a straight stream application, the stream is no longer hollow, but solid with air bubbles. This does the same job as the solid stream.

Not for nothing and not to be argumentative...but a manufacturer and/or their rep is the last place I think of when it comes to getting certain "FACTS" about applications, tactics and "theories." At what point are they suppose to or going to say anything that doesn't market their product? You can't have it both ways. I have used TFT's, I have see what happens when you underflow TFT's and the stream still looks the same. This is at flow losses of over 25%! Yes TFT's when in straight stream are not a hollow stream...then again so aren't the other 95% of manufacturers combo nozzles that are the market...so what's the point? The point is that it is still the same stream made of equally sized water droplets focused into a straight stream.

Flow is what is comes down to regardless of what nozzle is on the end. Proper hand line selection. Proper hydraulics to ensure the proper flow regardless of what size room it is what is burning and so on. Proper fire stream management.

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A note on my limited knowledge of standpipe ops. We havce a few but all in basically lowrise (5 stories) buildings. But that said, I know the code used to mandate that the system be capable of maintaining 65 psi at the highest outlest. Sometime in taller buildings this resulted in having to add PRV (pressure reducing valves) at lower points and these PRV's could be adjusted. But higher up the target was only 65 psi, therefore requiring a low pressure nozzle and really 2.5" hose to eliminate as much friction loss as possible. Newer systems I beleive have higher pressures or at least the FD can require a higher pressure at the highest point. I guess my point is, you need to know what you have in your area. If you have a lot of older standpipes you should be think 2.5" with a smoothbore. And as Johnvv points out a lot of debris and scaling rust happens in these systems potentially reducing your flow even more.

And ALS is right on when he says no one should advocte not having any nozzle type available on every engine. Some situations will dictate a fog over the solid stream. Know your tools!

Lastly, while I wholeheartedly agree that all firefighters should understand the hydraulics of making a good firestream, I have to admit that I'd just rather have premarked gauges and standard (tried and tested) friction loss numbers for given discharges. It's too easy for (not a career MPO) firefighters to miscalculate at 0300 hrs. and underpump the TFT or rip the knob from someones hand with too much PSI.

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This going to be my last post on this subject because it seems more is being read into this than I have stated.

1) I have always agreed that the proper amount of water is required never mentioned 40 gpm We all know what the minium is.

2) The only reason for bringing the example of the xmas tree was, most people can actually see what is happening with the stream and fire.

3) The example of the task force tip nozzle was only that It was shown and explained how the stream becomes solid again.

4) The only experience I have had with Task Force tip is in training other Depts. I personnaly was always exposed to Akron.

5) The protection I spoke about was not letting the fire over power you on entry, thats why I gave the example of the xmas tree. Please dont read into what I have written.

6) We don't need a hydralics class at the fire scene. That was what I was trying to say. Try the nozzles with an open mind either at drill school or behind the fire house, I have done this and thats is part of the reasons for making my comments and opinions. Whether some manufacture gives you the information or not you have to try it yourself, there is, because as was said, there is to much BS and the BS meter is not always in working order.

7) I was also trying to point out and I guess i didn't get it accross that the fog nozzle can do the same job as the smooth bore with limits and you can do more that one type of operation with it. To change a nozzle during the intial attack I don't know about that.

It has been a good discusion and I hope I have been able to have some closed minds, not any one that has written their opinion, to investigate and try it for themselves.

The last thing John mentioned is a good point, but in all my years on the job and instructing since, I have very rarely had debree, I know its there and all you need is one time, but that is quite awhile. I you are working in the projects yes we did have the debrie, but for the most part its didn't show its ugly face.

Its been a good discussion and have a good day, this can go on forever

Larry

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