Where's the deuce n a 1/2 ?

[Jason762 2]

Sounds like the difference between a 1 1/2 and 1 3/4 debate they had years back.  For us I don;t think running all 2's would help us cause of man power.  We usually only have 2 guys per line.  Can 2 handle a 2" ok?

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2 people can handle a 2" line, BUT there are several things to be aware of:

-they will take a bit of a beating on the line

-with only 2 people there is no one to chase kinks, which can be extremely detrimental to an effective flow rate.

-with only 2 people there is no one on the line or adjacent to it that can watch your back i.e look what's going on around, not letting the fire get behind you, etc.

-there will be no one to halp advance the line around corners, up stairs, etc.

Of the few things I've listed, you must encounter these problems anyway with only 2 people on a line regardless of hose size. Why don't you have more people on a line? How about teaming up companies to put the first line in operation. First line placement is one of the most important things on the fireground. This needs to take priority over almost any other action, except the obvious (recue needs, exposure protection, etc.).

[CFD320 35]

Sounds like the difference between a 1 1/2 and 1 3/4 debate they had years back.  For us I don;t think running all 2's would help us cause of man power.  We usually only have 2 guys per line.  Can 2 handle a 2" ok?

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I'm a big guy and have no issue with me and any other guy on a 2" line. I have heard 2 smallish guys complain about the 2"....

There was a comment above about "throwing out" all nozzels other than smooth bore. I will be happy to show in reality that I can get more water with less reaction force out of the automatic compensating TFT tips we run than a 15/16 smooth bore. We dont use the TFT's on 2.5" 0nly 2".

Edited March 4, 2006 by CFD320

[Jason762 2]

I'm a big guy and have no issue with me and any other guy on a 2" line.  I have heard 2 smallish guys complain about the 2"....

There was a comment above about "throwing out" all nozzels other than smooth bore.  I will be happy to show in reality that I can get more water with less reaction force out of the automatic compensating TFT tips we run than a 15/16 smooth bore.  We dont use the TFT's on 2.5" 0nly 2".

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CFD,

Here is one of the main problems with the TFT, you have no idea when on the nozzle if you have an effective fire stream or not. The stream and pattern appear to be good, but in reality the nozzle is not flowing enough GPM's. The GPM's are what puts out the fire not the pressure. This problem has been documented by many big city FD's and has led them to no longer use the TFT. Many of their FF's thought they were flowing the GPM's that the nozzle is designed for but in reality they were flowing way less and many times it was of no fault of the pump operator. A kink in the hose will severely reduce your GPM (up to 30% at a 90 degree bend I believe)and with the TFT you will have no idea about this loss of GPM. With a smooth bore you will know when something is going wrong.

Also I would like to hear how you get more GPM with less reaction force out of a TFT than a smooth bore

Edited March 4, 2006 by Jason762

[CFD320 35]

CFD,

Here is one of the main problems with the TFT, you have no idea when on the nozzle if you have an effective fire stream or not.  The stream and pattern appear to be good, but in reality the nozzle is not flowing enough GPM's.  The GPM's are what puts out the fire not the pressure.  This problem has been documented by many big city FD's and has led them to no longer use the TFT.  Many of their FF's thought they were flowing the GPM's that the nozzle is designed for but in reality they were flowing way less and many times it was of no fault of the pump operator.  A kink in the hose will severely reduce your GPM (up to 30% at a 90 degree bend I believe)and with the TFT you will have no idea about this loss of GPM.  With a smooth bore you will know when something is going wrong.

Also I would like to hear how you get more GPM with less reaction force out of a TFT than a smooth bore

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First, if you cant tell you have a kink with a TFT its news to me, Ive had plenty an can always tell. Second, I will agree that if you have a pump WITHOUT flow meters you should not even consider using automatic nozzles. The MPO has to be on the ball, my engine does have flow meters and all of our operators are trained to watch flow very closely.

I am not anti smooth bore, in fact am a proponent of them on pumps with no flow meters and line over 2".

As for the second part go look at the low pressure tft flow/reaction charts on their web site....I would be happy to get together with you and flow some water, I didnt believe it myself until I did it. We ran the 1000gal (950 in reality) gal tank on 118 dry with 2 2" in operation in 116 seconds (I think its been a few years)

[Jason762 2]

First, if you cant tell you have a kink with a TFT its news to me, Ive had plenty an can always tell.  Second, I will agree that if you have a pump WITHOUT flow meters you should not even consider using automatic nozzles.  The MPO has to be on the ball, my engine does have flow meters and all of our operators are trained to watch flow very closely. 

I am not anti smooth bore, in fact am a proponent of them on pumps with no flow meters and line over 2". 

As for the second part go look at the low pressure tft flow/reaction charts on their web site....I would be happy to get together with you and flow some water, I didnt believe it myself until I did it.  We ran the 1000gal (950 in reality) gal tank on 118 dry with 2 2" in operation in 116 seconds (I think its been a few years)

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I'm not sure if we are on the same page here. Are you saying you can always tell when there is a kink if you are the MPO or when you are on the inside. As an MPO I would have to agree with you, yes you should be able to tell, but on the inside I have to say no, you would not be able to tell unless it was such a severe kink it cut your water supply completely or close to it. Otherwise you would still have a line that felt hard, had a good pattern. and appeared to be flowng adequate GPM based on the whole design behind automatic nozzles.

[Jason762 2]

How about a 2 inch handline less weight easy to handle

200' of 2" with 15/16 tip = 240 gpm  PP approx 100psi

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DC2T,

How did you come up with this number? Using the formula GPM=29.7xsq root NPxDiameter of the orifice squared you get around 185 GPM from a 15/16 tip at 50 psi. At that flow you lose approx 27 psi per 100 feet (friction loss)leaving about 46 psi for the tip. Close enough to the 50 psi needed at the tip.

Now say you were able to get 240 GPM from a 15/16 tip, you certainly couldn't do it with a pump pressure of 100 psi. At 240 GPM you lose approx 46 psi per 100 fet of 2" hose leaving approx 8 psi for the nozzle based on your statement of flowing 240 gpm at 100 psi PDP through 200' of 2". Not sure how you got this?????

Edited March 4, 2006 by Jason762

[Guest alsfirefighter]

As far as TFT, I agree with Jason, that is a downfall of automatic nozzles is it will maintain a stream if the GPM's are not correct.

CFD, I can also show you articles written by those whom have done tests that say your right and wrong. I came from a department that used nothing but TFT and I never cared much for them, and they still seemed to need a lot more muscle power to control then when we finally bought a few smoothbores.

When is the last time you've had those automatic nozzles calibrated?

How many of you know that they even have to be calibrated?

No calibration on a smoothbore. Better penetration, solid stream of water, no little drops, and if you have newer smoothbores, some are much lighter then having the oversized stream selector found on many TFT models.

One final thing, the 1 1/2 compared to 1 3/4 is nothing compared to the benefit you can get from going up from 1 3/4 to 2". 2" with a smoothbore is not that difficult for 2 persons to handle with good technique, and experience, which comes down to training with it.

[IzzyEng4 427]

To Jason to answer your question about why we have 2 guys on a line. It usually depends on what time of day, manpower is the issue since my department is a vollie department. So that would be a major consideration. Plus the fact that our running rules are a bit different than some. We have 5 engine companies, 3 are single engines company an the other two have the ladder at one house and the squad/rescude at the other engine company house. So if it is in the middle of the day, we try to split up the companies but that sometimes dowsn;t work for us. This issue is being addressed now since this is becoming more of a problem in the last few months. If it is a night, like most volunteer fd's we get too many people and we can assign them to specific assignments.

2 inch might work for us, but we'll obviously have to train a lot on it.

Also to ALS, just to let you know, I wasn't comparing the 1 3/4 water to a 2.5. I was comparing the discussion how 1.5" and the 1 3/4 comparison is like the 2" to 2.5" discussion. That's all. Sorry if I confused you on that.

[STAT213 332]

Ok, all you smooth bore fanatics...

I agree fully that the smooth bore has its place, and is a great nozzle. How 'bout foam? Can't do it with a smooth bore, right? What do you feel are the advantages to having a smooth bore vs. the ability to flow foam? From what I have been taught, (I am talking about Class A foam here) adding foam to your water gives a huge advantage. So, add that to the discussion...

[Jason762 2]

Ok, all you smooth bore fanatics...

I agree fully that the smooth bore has its place, and is a great nozzle.  How 'bout foam?  Can't do it with a smooth bore, right?  What do you feel are the advantages to having a smooth bore vs. the ability to flow foam?  From what I have been taught, (I am talking about Class A foam here) adding foam to your water gives a huge advantage.  So, add that to the discussion...

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I don't know of any FD's using Class A foam reguraly(in this area). If any one is let me know how it is working out, for us, it is not a consideration at this time. I have heard they are having great success with it in Europe but I have not had the time to do any research on it. Who's using it in this area?

[Guest SQUADco119]

FYI- combo nozzles are great never had a problem with them in my expierence but smooth bore nozzles are always a solid stream, combo nozzles are always broken up even if it appears to be solid its not as solid as the (solid bore). Hey who cares what u use i think its more important how you use what your using that. Every fire calls for different actions i will ive seen 1'3/4 do wonders knock down more fire faster cuase its munuverble and you can have multople with less manpower. that doesnt mean you wont need the big guns sooner or later.

[DMA327 12]

While a smooth bore nozzle on an inch and 3/4 is great for maneuverability and enables you to knock down some descently advanced fire, you will not be able to knock down a fire such as Hudson was talking about without a 2 1/2 because of the excellent penetration and force of a 2 1/2 especially with a smooth bore nozzle on it

[IzzyEng4 427]

There is a right time and place for Class A foam. Too many departments use it wrong. And of course you have to you an adjustable / fog nozzle for it.