Fog nozzles have better penetration than smoothbores?

[erics99]

I was reading a book today at work about fog nozzles, published by Fire Engineering/PennWell. In the book, it said that 100 PSI fog nozzles set on straight stream have better hitting power/penetration than a smoothbore nozzle (same GPM for both nozzles). I am curious to your opinions on this.

Also, skimming through the book, I noticed that this biased book claimed that a smoothbore line with an 1 1/8 tip (266 GPM) had a nozzle reaction of 123 LB, compared to 126 LB on a 100 PSI fog nozzle while flowing 250 GPM. However, in reality, an 1 1/8 tip has only 99 LB reaction force, while the 1 ¼ tip (328 GPM) has 123 LB reaction force.

It’s pretty sad that a book biased on fog nozzles and bashing the smoothbores can’t even get the numbers right. Anyway, I thought this might get some (non-flaming) conversation going.

[UsingAllHands]

My Favorite Subject!

Eric:

While it may be true that a combination nozzle set on straight stream, operating at 100psi may hit harder than the same GPM out of a smoothbore Nozzle at 50 psi, I can tell you from EXPERIENCE, that the line with the combo nozzle will be UNMANAGEABLE due to the extreme nozzle reaction force. And I do mean UNMANAGEABLE!

What inevitably happens when those 100psi combo nozzles are used, is that due to the unmanagability of the line at those high flows, the nozzleman will either instinctively reduce the flow by gating back the nozzle, or frantically call for "less pressure" to be pumped on the line. The result: Less GPM flowed onto the fire, and/or much more exertion required by the nozzle team. Oh, yeah, and there goes your "harder hitting stream and greater penetration, too!"

Yes, it's a shame that a biased book would also be printing erroneous information to support their conclusions.

As far as this topic is concerned, research (both here and elsewhere) will show you that there are many supporters on both sides of the fence. This could leave you confused, unsure, and wishy-washy about nozzle selection. In fact, if you read other threads in these forums on this subject, you'll see that many people just say "Whatever works for you," or "It doesn't matter what nozzle you use." Those are indecisive and inconclusive remarks that still leave you searching for the truth.

My challenge to you (and everyone else here) is to see through the B.S. When reading anything, ask yourself 2 things: First, is the author speaking from EXPERIENCE or just reguritating something they heard someone else say? (or worse...citing false info.) Second, what are the motives of the author? I remember reading articles in national publications touting the wonderful benefits of a particular nozzle, only later to notice the fine print, where I learned that the author was the V.P. of a well known nozzle manufacturer who wanted to push his crappy product.

Me? I'm just a fireman who knows the truth (from experience)
and wants to pass what I know along. I don't sell anything. I'm not looking to make any money off of anyone. I couldn't care less if nobody ever knows my name. I just like fighting fires and I know what I know. The truth is out there.

[Pride373]

I believe TFT has a study on their website in which they measure the force at which fog and smooth bore streams hit.

TFT (fog) streams hit "harder", meaning the speed at which they hit the fire is faster. Some say this would reduce the ability of the stream to evaporate before it hits the center of the fire. I say...

Who freakin cares. I'm so sick of this argument that I'm ready to go into my next job with my thumb over the coupling.

[erics99]

Originally posted by Pride373
I believe TFT has a study on their website in which they measure the force at which fog and smooth bore streams hit.

TFT (fog) streams hit "harder", meaning the speed at which they hit the fire is faster. Some say this would reduce the ability of the stream to evaporate before it hits the center of the fire. I say...

Who freakin cares. I'm so sick of this argument that I'm ready to go into my next job with my thumb over the coupling.

Nobody is forcing you to participate in this conversation.

[E229Lt]

Here we go

[Lewiston2FF]

LMAO!

Nice one Lt. Where do you find those things?

[ff7134]

Perfect.

Wait isn't that Seattle slew rising from the grave and getting beat by 2 men in bunkers one with a straight tip and the otherwith a fog????

[FlyingKiwi]

if you want some bed time reading on this and other fire related things, try http://www.bfrl.nist.gov/fris/ they have all sorts, including downloadable modeling tools, one of which is titled FIRDEMND - Handheld Hosestream Suppression Model at http://www.bfrl.nist.gov/866/fmabbs.html#FIRDEMND .

This computer simulator does the following..

simulates the suppression of post flashover charring and non-charring solid-fuel fires in compartments using water sprays from portable hose-nozzle equipment used by the fire departments. The output of the Fire Demand Model (FDM) shows the extinguishing effects of water spray at various flow rates and droplet sizes. The calculations are based on a heat and mass balance accounting for gas and surface cooling, steam-induced smothering, water-spray induced air entrainment, direct extinguishment of the fire by water and the energy transport via inflow and outflow of heat and products of combustion. This model can be complicated, but it is very powerful.

So if you want to run some test using real world and or manufacturers specs use it and see the results.

[FireCapt1951retired]

drkblram,

I know it's not popular but I aree with you. The best damn nozzel I ever used. Damn I miss it.

[mcaldwell]

I still say it depends on whether it has Red handles or Yellow handles, whether it is used by a Vollie or a Career, and how many lights you can attach to your helmet.

[hwoods]

Here's the test results.............

After serious deliberations on the subject of "What Has Better Penetration, Smoothbore or Combination?" I decided (I'm a Chief, we decide to do things) to run some tests. Here's what we got:

First we acquired a standard issue Chief Officer, (5'10", 200#, 61 years old, 45 years experience) armed with a 1.5 Handline equipped with a ball shutoff and a 1" Smoothbore tip and a Combination tip.

We then located a suitable wall (0.5 Sheetrock on 2x4 studs)

The line was charged to 100 psi, the 1" tip applied and the Chief hauled back and jammed the tip into the Sheetrock. Tip penetration was up to the pistol grip on the pipe. We then changed to the Combo tip and repeated the operation. The combo tip broke a wider area of sheetrock, but only went in about 1.75"

CONCLUSION: The Smoothbore penetrated farther.

[erics99]

Re: Here's the test results.............

Originally posted by hwoods
After serious deliberations on the subject of "What Has Better Penetration, Smoothbore or Combination?" I decided (I'm a Chief, we decide to do things) to run some tests. Here's what we got:

First we acquired a standard issue Chief Officer, (5'10", 200#, 61 years old, 45 years experience) armed with a 1.5 Handline equipped with a ball shutoff and a 1" Smoothbore tip and a Combination tip.

We then located a suitable wall (0.5 Sheetrock on 2x4 studs)

The line was charged to 100 psi, the 1" tip applied and the Chief hauled back and jammed the tip into the Sheetrock. Tip penetration was up to the pistol grip on the pipe. We then changed to the Combo tip and repeated the operation. The combo tip broke a wider area of sheetrock, but only went in about 1.75"

CONCLUSION: The Smoothbore penetrated farther.

Sounds like we have a winner!

On a serious note though...1 inch tip on an 1 1/2 line? That's a lot of friction loss to get 50 lbs on the nozzle!

[ff7134]

what about the Akron SabreJets..they are always good for discussion.

[ff7134]

I believe that a straight tip gets best penetration while wearing 3/4 rubber boots(rolled bown of course ) A leather helmet w/Bourkes and no safety glasses or goggles, and a rubber coat.

[hwoods]

For The Record.........

It was a Canvas Duck coat, Black, of course, and no reflective stripes. Friction loss was not considered because we were not flowing any water, simply seeing how far the nozzle would penetrate.......

Oh BTW Artie, nice shot.....

And... Akron Saberjets?? A hockey team, right??

Stay Safe....