Best Supply Line Size???......

[neiowa]

It may be the only way to go in your district and with your resources, but LDH doesn't come without its drawbacks. I also fail to see how hook up is any quicker.

OK so twice with this. Name the drawbacks.

If you're installing hydrants (or replacing) are you installing Storx hydrants or antiques? Storz are same price as steamers.

[nameless]

OK so twice with this. Name the drawbacks.

If you're installing hydrants (or replacing) are you installing Storx hydrants or antiques? Storz are same price as steamers.

I know the drawbacks, the point is to have the people knelling at the feet of the LDH god to admit that LDH isn't some magical hose that has all of these advantages with no trade offs.

If you commonly put a pumper on the hydrant and/or have short lays LDH won't give you an appreciable benefit.

If you don't have PD or fire police on your heels to shut down the road, LDH can be damaged by cars trying to drive over it.

If you dont have attack rated LDH you can't put as high pressures through it as 3inch lines.

If you lay 1 line of LDH vs. 2 lines of 3 inch if there is an issue with the LDH you have no water. If one of the lines of 3 inch is messed up, you shut it down and still have 1 line and some water until secondary water is made.

You can shut down one of the 2 lines when the fire is controlled, pick that up and leave the single line for overhaul allowing your companies to get back in service quicker.

3 inch can be moved once its charged, and is less likely to shut down the road for incoming units.

I'd venture to say it'd be close to impossible (if not impossible) to find an engine out there that doesn't have at least 1 inlet and outlet that'll accommodate 3inch line without using adapters. Where as not every engine has storz connections or adapters.

Hose left in the supply bed after the lay can be used for large caliber handlines, "blitz" monitors, or other monitors. An engine with LDH either has to make room for 2 1/2 and 3 inch in the bed or loose flexibility by picking one or the other.

As said before LDH is heavier per length.


See what looking at it objectively does for us? Now if I was in an area that wasn't well hydranted, I'd take the trade offs for LDH. But when you have good hydrants that are 300-600 ft apart, the LDH isn't worth the trouble. The dual 3" have their drawbacks, but they have a lot of benefits when used in the right environment.

[Bones42]

I know the drawbacks, the point is to have the people knelling at the feet of the LDH god to admit that LDH isn't some magical hose that has all of these advantages with no trade offs.
- definitely not kneeling at the feet of a LDH god.

If you commonly put a pumper on the hydrant and/or have short lays LDH won't give you an appreciable benefit.
- true, but we don't put pumpers at hydrants.

If you don't have PD or fire police on your heels to shut down the road, LDH can be damaged by cars trying to drive over it.
- we used to use 2 1/2" for supply. Got run over many times by cars. Since switching to 4" and 5", we have had 0 run over by cars.

If you dont have attack rated LDH you can't put as high pressures through it as 3inch lines.
- true. Of course, have not needed (and can't see a reason for) more than 150psi in it so I don't see this as an issue.

If you lay 1 line of LDH vs. 2 lines of 3 inch if there is an issue with the LDH you have no water. If one of the lines of 3 inch is messed up, you shut it down and still have 1 line and some water until secondary water is made.
- true. And if those 2 3" lines are from 1 engine and the engine has a problem...you still have no water.

You can shut down one of the 2 lines when the fire is controlled, pick that up and leave the single line for overhaul allowing your companies to get back in service quicker.
- Been a long time in timing the difference between packing 800' of 5" compared to 800' of 2 1/2", but really don't remember it being much at all. And only have to pack it 1 time as opposed to 2 times.

3 inch can be moved once its charged, and is less likely to shut down the road for incoming units.
- true.

I'd venture to say it'd be close to impossible (if not impossible) to find an engine out there that doesn't have at least 1 inlet and outlet that'll accommodate 3inch line without using adapters. Where as not every engine has storz connections or adapters.
- majority of engines in my area have the Stortz adapters already in place on their discharges. We also have towns in my area that decided to have their hydrants on different thread standards than others. (and I assume your talking 3" with 2 1/2" couplings)

Hose left in the supply bed after the lay can be used for large caliber handlines, "blitz" monitors, or other monitors. An engine with LDH either has to make room for 2 1/2 and 3 inch in the bed or loose flexibility by picking one or the other.
- and if you lay all the 3" for your dual supply lines, now you don't have hose for that handline/monitor/etc. Sounds like bad hose bed planning to me. But, I can see your point.

As said before LDH is heavier per length.
- true.

See what looking at it objectively does for us? Now if I was in an area that wasn't well hydranted, I'd take the trade offs for LDH. But when you have good hydrants that are 300-600 ft apart, the LDH isn't worth the trouble. The dual 3" have their drawbacks, but they have a lot of benefits when used in the right environment.
- and we did look at it objectively as well. And it does work for us.


Good Post Nameless.

[Rescue101]

Try your objectivity in MY area.I'll bet you'll lean heavily to LDH. Good post though.As set as YOU are for 3(fittings,tactics,etc)we're equally or more set for LDH operations. As I mentioned earlier we can lay and pump(to capacity)over a mile of LDH. Just out of our dept,never mind the like equipped MA companies. Obviously we each use what we're familar with that works best for our areas.We're not going back,we're going bigger.Oh,I'll keep the 2-300' of 3 we have for utility use but not water supply.With the system you have and the hydrant spacing,I'd probably have a split load. But that's me and over a quarter century of LDH work.As long as the water gets to where it has to be,it's all good. T.C.

[nameless]

like I said at the end of my post, its dependent on the area. At times it seems people have jumped on the bandwagon without realizing with all the benefits of LDH, you do take some trade offs compared to 3" lines.

[Rescue101]

Hope my post didn't come across that way but I still contend that a 5 will deliver more water over DISTANCE than twin three's. I like 3 OK we just never had much of it.And there aren't too many hydrants in a lot of the outskirts.Ergo the LDH. And like any system you're used to and set up for,it works very well.Same as the 3 works for you. T.C.

[neiowa]

We've used Angus 4" for years. We're switching to Mercedes Megaflow 5" starting with the Quint and phased in over the next five years. T.C.

Is the Megaflow actually a double jacket hose. Website says is DJ but specs don't read that way and no photo of hose posted.

[david15845]

I have experience using 5", 3", 2 x 3", and even 2.5" (long time ago...).

For water you know you will not run out of, use the 5". I personally think it is just as easy to repack, and being rubber not woven jacket it lays flatter and nicer than some 3" would.

For most fires though, the 3" is more than enough. A double 3" gets you what a 4" would get you, and that better be enough in all reality.

The best solution, IMO, is put at least 750 gals on your engines. Have the first engine roll to the scene and the second in company make the hydrant IF IT IS NEEDED. The first in engine will know if you need the line when they get on scene. You don't need more than 750 gallons on 90% of all structure fires. Put the 5" on your engines, use it when you really need it. That way you have it and aren't laying it all the time.

I couldn't agree more. For master streams 5 inch hose is a must. There is too much friction loss with 3 inch. The last fire we had was a fully involved house fire with exposures. The 2 adjacent houses had fire in the attic. Our 2nd engine was maxed out (1250 GPM pump) when we started using master streams. I know we were flowing way over 1000 GPM and you can't do that with 2 - 3 inch supply lines.

[CadetNoble]

JUST USE FIVE INCH =-D I hate LDH too but it has to be used

[HeavyRescueTech]

If you dont have attack rated LDH you can't put as high pressures through it as 3inch lines.
- true. Of course, have not needed (and can't see a reason for) more than 150psi in it so I don't see this as an issue.

only time I have ever considered or been to told consider pumping LDH at high pressures is when an engine is supplying a pumpless aerial, fully extended, with the stick/tower flowing water. that was the only time you would need to worry about high pressures and "attack" LDH

[MEAN15]

Who says you can't move a charged 5-inch out of your way? It can be done. Just did it about a month ago.

[nameless]

Who says you can't move a charged 5-inch out of your way? It can be done. Just did it about a month ago.

a 100 ft section of 5inch weighs about 850lbs when filled with water. Not saying it can't be moved by its labor intensive

[ChiefKN]

a 100 ft section of 5inch weighs about 850lbs when filled with water. Not saying it can't be moved by its labor intensive

I didn't find it that difficult. But we don't lift all 100 feet at once, so maybe that's the problem.

Try lifting five feet at at time.

[txgp17]

I didn't find it that difficult. But we don't lift all 100 feet at once, so maybe that's the problem.

Try lifting five feet at at time.

+1

Just like eating an elephant, you do it one bite at a time.

[johnny46]

I didn't find it that difficult. But we don't lift all 100 feet at once, so maybe that's the problem.

Try lifting five feet at at time.

That. Was. Awesome.

[MEAN15]

Our truck was the 4th in truck on a downtown commercial fire. Had to move 5 inch to get the truck into position.

I didn't move it by myself - there were 6 of us.

[AbduNur]

I'm reading all of these posts from guys who say they don't need LDH because 3" works fine and it boggles my mind. Does anyone here remember the Super Sofa Warehouse Fire a few years ago and all of the NIOSH reports and recommendations after the inquiry. They literally ripped that Fire Department apart from bad Command structure down to inadequate hose diameters. They also did not carry LDH(4" or 5") and for the record, 3" is not considered LDH. We as the Fire service must use LDH(4" or 5" is your preference) in order to combat friction loss and different gradient factors that are not addressed with 3" line. This is proven fact, not theory or opinion. 3" has it's applications(FDC, supplying smaller hand lines through gated valves, ladder pipe operations, etc...). But, for supplying an Engine Co for an attack, why wouldn't a person want more water? Another post here that baffled my puny Truckie mind is when did we start fighting entire structure fires off of a booster tank's capacity? One member here posted that every Engine should be at least 750 gallons and the 2nd due Engine can resupply the 1st due Engine if needed. What do you mean, if needed? I could care less if an Engine has a million gallon booster tank, we should only use the booster tank for initial attacks until a hydrant is connected by either the 1st due or 2nd due Engine. The booster tank is designed for 2 things in regards to structure attacks: 1) an initial attack while the hydrant is being connected and 2) if something goes wrong with the water source(hydrant, supply line, drafting tank, etc...) the booster tank is designed to afford an Engine Co enough water to protect themselves or get out safely. Please, this is not my opinion..This is pure fact and any Firefighter who is serious about his/her pumping skills and Enginemanship will agree that 4-5" offers less friction loss and more residual pressure than a 3" line coming off of the same hydrant. I know that LDH is heavier and more cumbersome. But, we are all full grown men/women and we have to do what's right. Please forgive me if I have offended anyone..My only intent is to ensure that every Firefighter goes home safe.

[Rescue101]

You FAILED to take one minor item into consideration. We DON'T all live in a HYDRANTED district. So there goes your supply line MUST be attached the Hydrant to fight fire theory.That's why a lot of us country folk have large(1000+) booster tanks so we can run sustained operations until the second source is established. Also the reason we run big water tankers for the non hydranted district. Some areas in the country have NO HYDRANTS whatsover: What do you propose THEY do?Sorry,your blanket statement doesn't wash. The Super Sofa incident is a somewhat poor choice of arguement as water supply lines was only a small portion of the total picture. A factor? Certainly! But NOT the coffin nail. It would be easier(and take up less space)to list what went RIGHT. T.C.

[nameless]

adbunar, stick to the ladders and we'll worry about the hose ok?


Your statements shows you've drank the LDH kool-aid while not actually weighing the benefits and downsides of LDH or MDH.

I'm serious about my "enginemanship" and know that 3inch has its uses in certain areas and that LDH does in other areas.

[BoxAlarm187]

a 100 ft section of 5inch weighs about 850lbs when filled with water. Not saying it can't be moved by its labor intensive

I wanna purchase a 100' length of 5" hose that only weighs 17 pounds when empty!

"You can't move charged LDH" is a pet peeve of mine. Using a short section of webbing that you ought to be carrying in your pocket anyway, just put a girth hitch around the hose, and then drag it anywhere you want to. Using one person, not six, move it wherever you want to.

And I think that there are some people on here that understand that there are times that 3" is applicable, and times that 5" is applicable. There isn't a "one size fits all" supply line out there. Hell, just look at Harve's county, the massive amount of fire that they catch, and the abundant use of 3" hose there (dual lines every time?!). Maybe they know something we don't?

The new engine at my VFD will be carrying both.