Large Diameter Fire Hose

[PJ]

What are the pros and cons of using large diameter (5" or 6") fire hose?

[Nate Marshall]

More water, less friction loss!

This is where we need Larry Stevens. May want to email him or check his site.
www.isoslayer.com

[jj1967]

LDH is the only way to go. The initial outlay may be expensive, as it will require several adaptors and appliances, but it pays off in the long run.

LDH reduces (and in many cases eliminates) the need to relay pump or reverse lay. If I were writing the specs for a new truck I would include a five inch gated intake on each side as well as a five inch discharge on each side to maximize the capablities of the LDH.

The only disadvantage to LDH is it is heavy. Where you charge it is where it stays, and it is a pain to pick up and repack. Having said that, I would never go back to dual 2 1/2 or 3".

[OLE]

We use 4", but I wish we had 5". LDH is great! I agree if all the above plus it's not as critical to wash or to hang back up in the hose tower to dry! Stortz fittings are great too. When reloading, simply unhook stortz fittings and empty out water, straddle the engine over the hose and reload it right at the scene. Good Luck!

[Daron]

I have to agree with everybody else. Friction loss is the key. You have a hydrant that will put out say 750 gpm's at the hydrant with nothing hooked up it how much can you actually use 400 or 500 feet away at the pumper. With 3" you will lose most of it. As far as 4" or 5", the 5" will give way less friction loss than the 4" but you can fit a lot more 4" on the truck for those really long relays. I perfer the 5" myself. You can't pump what you don't have. I would rather spend a little more effort picking up less but bigger hose after the fire when there is no rush than sacriface resourses I may need to put the fire out quickly and safely. It is more expensive but not that bad when you consider only having to put one line on the ground instead of 2 and using less personel and equipment for suppling water instead of fighting fire. The strotz connections are a plus too since they are sexless and can be run in either direction. If you still plan on using a shuttle operation due to distance calculate the refill time at a hydrant with a 5" hose compared to smaller supply line.

[Capt. Zada]

Nate, you had better watch out, that brown stain on your nose may become permanent!

[HOTDOG]

Hey guys....
LHS saw all the attention that DFD was getting with his multiple personalities that he decided to try it...

Guess what his name is......


Yep...Nate Marshall. It's obvious with all the back patting and a** kissing.

Just an observation...

Be safe!!

[LHS*]

I like 7 and a quarter inch hose with 6 inch couplings, 3 psi lss at 2000 gpm.

[C. Pete Rickard]

6" How much fire you got there boy?

Evaluate your risks first and go from there. If all you need is 500 gpm the 4" should work fine.

1,400' of 4" with a 65 psi hydrant will give you 750 gpm at the end.

Need more help it's [email protected]

[Parafiremedic]

LDH, Love it. Our department likes the stuff so much we have changed the codes so that all new buildings with sprinkler systems will have 5" Storz connections for the FDC, instead of the ole twin 2 1/2" FDC's. We are also going to have all new hydrants turned 90 degrees to the road. This puts the steamer inline with the lay, instead of making the hose take up a lane of the roadway. You say the fire is the other way, no problem, just loop the hose on the sidewalk, still doesn't block the road.

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All comments are the opinion of the author, and not of any service they are a member of.

[PJ]

Thanks to everyone for all the feedback on LDH.

[CaptCraig]

Parafiremedic, that's a good idea on turning the hydrant, I'll have to pass that on. What is your standard pressure you start flowing in the 5" Stz connection on a 100'lay?

[Parafiremedic]

Originally posted by CaptCraig:
Parafiremedic, that's a good idea on turning the hydrant, I'll have to pass that on. What is your standard pressure you start flowing in the 5" Stz connection on a 100'lay?

CaptCraig, The both ideas came from our new fire marshal. Just makes you slap your forehead, and wish you would of thought of it. As for pressures, we have a fairly good water system, and we use foward lays (2nd in engine most of the time) so we don't pump the 5". Just keep an eye on the compound guage, and a foot on the 5". Most of our Hydrants are no further that 800' apart, so our longest lays are 400' (most of the time). Most of the hydrants flow around 1000 GPM, with 50 psi residual. When I worked for another department that did pump 5", we would start at 100psi, and +/- it depending on the needs of the engine at the fire, or the supply of the hydrant since the friction loss is so small. If we where pumping to an aerial, then we would need 140 psi at the turn table. In this case we would just throttle up till the aerial operator said he had enough. Kinda low tech., low brained approach, but it worked. BTW, our new deck gun's ground base also has a 5" storz connection instead of twin 2 1/2".

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All comments are the opinion of the author, and not of any service they are a member of.