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I would like to start a discussion specifically on solid stream/smooth bore nozzles. I am interested in what size nozzles are being used as well as different stack tip configurations and why you use them. My department uses the following:
15/16" on 1 3/4" lines.
1 1/4" on all 2 1/2"s including high rise.
I would really like to here from departments using the (1 1/4" x 1/2") and (1 1/4" x 1 1/8" x 1") stack tips for hand line use.

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Replies to This Discussion

We use 15/16 for 1 3/4 and 1 1/2 for 2 1/2. Does anyone have any stats on the survivability of victims with sb vs fog nozzles? I have to do a class on using smooth bores for some of our narrow minded people and I want to be able to give some info when they ask why we use them other that saying cause the chief said so!
We use 1 1/4" on all our 2 1/2" lines. On our Engine, we have an "apartment load, San Francisco Load" that has a 15/16" on the 100' of 1 3/4". That's at my vollie house. We just did some flow testing at work using different tips (1",
1 1/8", 1 1/4") on our 1 /34", 2 1/2" & 3". I don't have the flows that came up with but as soon as I can get them I'll post them here. I was having to take an aerial ops class--I'm an engine guy at heart and it killed me to see them finally test the smoothbore vs. fog.
A lot of folks are using 1 1/4" tips on their 2 1/2" smoothbore? Can you guys really move that on an interior attack?
Try using a 1 1/8" tip, and run it at 40 PSI nozzle pressure. It is about 70 lbs nozzle reaction and puts out 240 GPM. It works out to 5 psi per length friction loss. Easier to move, good GPM, great stream. No NR. Inch and 1/4" is a bit much for moving inside!
We use 15/16 on our 1 3/4 lines.
We use 1 1/8 on our 2 1/2 lines.
Bro
I should of answered the question before offering opinions! Anyway, we use 15/16" on 1 3/4" lines and 1 1/8" on the preconnected 2 1/2". Spare 2 1/2" nozzles are lightweight Akron playpipes with stacked tips. We always start out with the 1 1/8" tip anyway, so the Chief buying the extra tips was a waste of money. I will say that the play pipes do not put out the stream that the Akron 1400 series shutoff does. It is also heavier by a couple of pounds.

One thing I did see in this blog was one of the brothers using a nozzle on a 3" hoseline. NFPA states specifically that 3" is supply hose. It is very dangerous to put a nozzle on. I have personally witnessed the tragic results of this practice. Don't do it. If you have to flow over 325 GPM, put the 3" into a master stream.
Russ: It's not my call on the 3". For some reason they had us train on putting it into service as an attack line the other week with a 1" tip. That worked like a bus wreck, I'm not sure why they had us do this. As of right now, the 3 inch is being used as supply but who knows in the near future. I'm going to talk to a captain tomorrow about all this. I'll let you know what I find out.
One of the questions I am often asked in regards to moving a 2 1/2" interior is how labor intensive it is. The answer here is training, if you train with it you can do it. Some tips we found that work for us is:
Start low .....Like Russ said start off at 40 psi NP. It think most people against using a 2 1/2" have had a bad experience with a line over pressured. Hose line... we have found that using the rubber coated nitrile (wash and wear) hose is lighter and moves around corners and obsticles better than the fabric coated hose. Russ I am a fan of the Akron 1400 myself.. good tool.
Bob
I think everyone here is on the "same side" as far as the nozzle debate. The question this blog should be asking is how to go about convincing everyone else, including the most important people...the folks who set policy. Jay Comella ( sorry Jay if I mis-spelled your name) had a great article in FE and he did just that, and was able to effect change. We can't and should not do away with combo nozzles. They have their place. I just want a choice, and to stop folks from cooking themselves. All be safe
Russ

Bob Shovald said:
One of the questions I am often asked in regards to moving a 2 1/2" interior is how labor intensive it is. The answer here is training, if you train with it you can do it. Some tips we found that work for us is:
Start low .....Like Russ said start off at 40 psi NP. It think most people against using a 2 1/2" have had a bad experience with a line over pressured. Hose line... we have found that using the rubber coated nitrile (wash and wear) hose is lighter and moves around corners and obsticles better than the fabric coated hose. Russ I am a fan of the Akron 1400 myself.. good tool.
We use 15/16 SS on the 1&3/4 finish (fogs on the crosslays) and 1&1/4 inch SS on 2&1/2. We generally don't have an issue advancing the line. It gets into a safe place dry, is charged, knocks down the bulk of fire then advanced. While the first engine has only 2-3 on the line, the next engine is paired if a 2&1/2 is off giving the line 4-6 men. The first 2-3 get the line inplace and hit the fire then the help arrives to advance the line. As for flow, if I'm going to lug a 2&1/2 I want flow and the 1&1/4 basically doubles the flow of the 15/16.

What gets me is seeing guys use a 1 inch tip on 2&1/2. They lug the line around for only 35-40 GPM. Use a bigger tip with less NP (as mentioned by Russ).

Before we had enough cash to make the whole bed 2&1/2 we out 100 feet of 2&1/2 on the end with the nozzle to make the line more managable.

Chicago has a tactic to increase the nozzle pressure to 80 PSI on a 1&1/4 inch tip when the lineis stationary and tied off making it a kindof master stream.
Depending on which manufacturer you believe, at 50 psi a 7/8" SB should flow around 161 gpm and 15/16" will give you about 182 gpm. Of course, it's always best to do your own testing...

The standard formulas for nozzle reaction are:

NR (lbf) = 1.57 x d squared x NP (smooth-bore), or;

NR (lbf) = 0.0505 x gpm x square root of NP (combination fog/straight or automatic nozzles)

(These are from Paul Grimwood, "NR" is nozzle reaction, "d" is tip diameter, and "NP" is nozzle pressure)

Our department carries both 7/8" and 15/16" tips on 1 3/4" lines. I prefer the 15/16" for its higher flow but, in reality, most people probably never notice the difference.
We use 15/16" also on our 1 3/4" lines, but have not yet changed from an adjustable on our 2 1/2" lines. (It is a newer style that has a 250 gpm rating so that is a positive.)
Joseph R Polenzani said:
Depending on which manufacturer you believe, at 50 psi a 7/8" SB should flow around 161 gpm and 15/16" will give you about 182 gpm. Of course, it's always best to do your own testing...
.
I'd just note that the above number come from physical science, and therefore never change, if your testing shows something different, check your measuring gauges.

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