Nozzles, Hoses and Pressures

[WTFD10]

First off, this is not meant to be a debate about which types of nozzles or hoses are better. I'm just curious about what other Ohio departments use currently and why you use it.

On your initial attack line for a SFD, do you use 1 1/2" or 1 3/4" hose?

Which type of nozzle: combo/fog or smoothbore?

What is your usual pump discharge pressure for this type of line?



We use 1 3/4", fog nozzles and a PDP of 120 PSI. Nobody really knows why other than it's what we've always used/everybody else uses it.

I would like to see us try a smoothbore on one of our preconnects because I think the lower PDP required will make a more manuverable attack line while still flowing good GPM.

[Weruj1]

We run all 1 3/4 with combination nozzles on them. We had the new one (s) firm Akron I think the combo SB/Fog........Saberjet ? what a pain in the rear. All 2.5 attack lines are smooth bore.

Pressures ? we have no actual psi, usually around 110-120, or when someone says gives more or give us less.

[firenresq77]

We use 1 3/4" with combo nozzle. Usually depends on who's operating the truck, but usually we set it around 100-110psi and then adjust per the attack team.

All 2 1/2" lines also have combo nozzles. I would like to try to get a couple smoothbores (1 for 1 3/4 and 1 for 2 1/2) to try out and see how they work.

[pfd3501]

Right now we use 1-3/4 lines (pre connect cross lays) with combo nozzles

If we hit our FEMA grant and/or some private sources come through, we may be able to add CAFS to our front line engine. Then we would use smooth bore nozzles with CAFS

[ff7134]

1 3/4" with Akron SabreJets at 100 PSI.


Come on Josh....its just a pain in the butt for us "Old Timers"
who are use to the Bail opening and closing the knob. I have gotten use to them now after alot of training.

Plus your a A.C. you shouldn't need to worry about how to shut off the nozzle anyways

[firenresq77]

We tried the Akron's, too and did not like them. Would be way too complicated for some of the folks to figure out......... Not saying it's the right reason for not doing it, but that's why we didn't get them.

[Weruj1]

well that doesnt mean that I dont like to put out fire.......used one on a training burn .........my opinion wasnt the only reason we pitched em ........LOL ............others did not like them either, however I am glad they work for some departments !

[WTFD10]

Originally posted by firenresq77
Would be way too complicated for some of the folks to figure out

We would have the same problem I'm afraid.

Hey Jeff, how's the nozzle reaction at 100 PSI while using the SB? I think with a regular SB it would be pretty strong.

[WTFD10]

Originally posted by ff7134
Plus your a A.C. you shouldn't need to worry about how to shut off the nozzle anyways

He would if he got sprayed by his crew because they couldn't shut the line down

[ff7134]

Moe,
Yeah the SB has some kick....as long as the guy on the knob is ready and they have a good backup its not bad. Some of the guys call for the pressure to be dropped but most don't bother because if you switch back to fog then you have to call for the pressure to be adjusted again.

We initially didn't like them but the Chief made us keep them on the trucks and after alot of training on with them we got so we really like them. It takes all of the guess work out of which line to pull. We should be getting our 2.5" Sabre's soon.

I can see it now Josh soaked and 2 newbies on a "wild line".

[Weruj1]

I can only imagine how much fun that could be !

[jaybird210]

Being an arrogant know-it-all, I'm going to butt in here (mostly just 'cause Josh likes to come butting into the Illinois forums.... )

If youse guys are running combos on 1 3/4" or 1 1/2", are these low-pressure fogs? Cause if they are conventional, you are way under-pumping them at PDP of 110-120psi. Is that a big deal? Only if....

I'll explain: I have in my hand a fog rated at 125 gpm. That rating is with 100 psi at the nozzle. If I've got 200 feet of 1 3/4", I have to compensate at the pump for friction loss through the hose. (Illinois State Fire Marshal says 33psi per 100'. We KNOW this to be wrong by way of flow testing. But that's another story). If I pump at 110psi PDP, there may only by 70psi or less at the nozzle. Is that a big deal? It depends on a couple of things: IF you are not expecting 125gpm, no problem. If you ARE, you could have trouble.

Here's our deal:
We run one preconnect 150' 1 3/4" with adjustable gallonage fog. We normally have this set at 125gpm. By way of flow testing, we found we need 135psi PDP to get 100psi at the nozzle. This is easily managed with two firefighters. The other preconnect is 200' 1 3/4" with a 7/8" smoothbore. Again, by flowtesting, we found that if we pump that line at 100psi PDP, we flow about 180gpm. That's a helluva lot of firefighting punch. Best thing: one guy can manage it without trouble (remember, SB are designed to operate at 50psi nozzle pressure).

Some interesting things came out of flow testing:

1. We also were under pumping our preconnects. We were averaging about 90gpm on the fog. Again, it's okay, if that's what you are expecting, and you pre-fire plans are based on this.

2. By swithing our 200' to a SB, we designated that our first-off line for a residential, confined fire (i.e. one or two rooms and contents). Plus, it's highly manueverable. AND, it packed damn near as musch punch as our 2 1/2" with a 1" tip. DOWNSIDE: that lower pressure can lead to kinked hose. Again, not a problem if you are expecting it.

3. Our 2 1/2" preconnect is 200' also. We ended up taking off one of the stacked tips (it's now a 1 1/8"). This should flow over 200gpm. Again, 50psi on the tip. We found that we only needed 80psi PDP for this line at this flow.

Flow testing smooth bores is a piece of cake. All you need is a pitot gauge and a chart. Flowing fogs a little more complicated; you need a flow meter. Most salesmen can get one; call your local Akron or Elkhart rep and tell him you want to evaluate nozzles. You can flow test yours and see what's new in low pressure fogs.

I'll get the heck out of here now. Sorry, Josh!

[ff7134]

Not a problem Jay,

And yes they are Low Pressure Nozzles. Running it at 100psi pump pressure get the needed PSI at the nozzle.

[Weruj1]

why is everyone all up in my business ? I welcome all comers .........plus 210 I genuinely like you ! stop back anytime...

[WTFD10]

Great post Jay, thanks!

We also have the low pressure nozzles but what we are actually flowing is probably anyone's guess.

That was one of my reasons for this thread, to see what PDP other's are using. I should have included a question on dual or fixed gallonage combo nozzles and also what their department's target gpm is.

I have read in many articles that for interior attack, 180 gpm is the minimum needed for safe operations. I'm sure you can get by with less for a basic room & contents job, but it would bite you in the ***** on something bigger, commercial structures, etc. Seems like it would be better to set everything up for maximum gpm. That way your not behind the 8 ball when it hits the fan.

A flow test sounds like a good daytime drill for my dept. That way we know for sure what we are flowing. Wonder if the neighboring city dept. has a flow meter we could borrow? (hint, hint 730 )

Thanks for the responses brothers.

[Weruj1]

Moe,
We got a pitot............lemme know if you need it .

[ff7134]

Just have Josh hold the Pitot when your testing

[Weruj1]

Man this is a tough crowd !

[jaybird210]

Just make sure Joshie holds his own pitot!

(Keep your hands off my pitot, man!)

[emstrainer]

Lets do some math here ....

Needed Fireflow = L X W / 3 X %involvement

Standard SFD - 2500 SF

Working Fire - 25% Involved on arrival, 1st floor.

This is a basic formula, and we already need 200 GPM for initial Fire Attack. This does not include extension into attic or 2nd floor if in a multi story occupancy. As a company officer I want to have the needed fireflow at my fingertips, not relying on radio traffic to ask for more water. Most of you replied that you try to achieve 100 gpm or 125 gpm. I would recommend evaluating your fire flow needs. Conducting flow tests seem to be very educational. We have 200' 1 3/4" pre-connects with Akron Selecto-matic Nozzles (SM20) and 200' 2" Lines with SM30. They will flow 200 gpm and 300 gpm respectively.

We used to strive for "100 GPM" based on "We've always done it this way" attitude. I would challenge you to question "WHY" and promote change. Fire Rescue magazine has been a great source of articles on Flow Testing, and Big Water from Little Lines. You should always maximize your nozzles. You can close the bail if needed to control the reaction force.

We have also added 200' 2 1/2" Pre-Connect with Straight Tip, and 200' 2 1/2" with a 500 GPM Blitzfire for Quick Deployment of Big Water. If you are like us, Manning is a precious commodity these days. We run 3 on the engine, and only have 10 on duty per shift.
We don't have the luxury of 2 or 3 handlines from the start ...

Any other thoughts ??

Jason Kinley, Lieutenant
Xenia Fire Division