What FyredUp said above.
There are two things that our department should change that I got from Grimwood's Eurofirefighter.
The first is: stop using the booster reel (40gpm) and use the 1 3/4 inch hose at 100gpm and 50-75 psi
and the second one is: use more modern nozzles that allow us to do effective 3D attacks.
And from what I hear and see we'll get there some day in the near future.
Edit: We use the 1 3/4 inch because that's the smallest line we have, apart from the booster reel. The next hose size would be 2 3/4 inch.
The more tactics you know and train on, the more situations you can adapt to... Sometimes we have manpower out the wazzoo, other times we are WAY short. Having a medium to big hitter on the front line that can get a knock may be the answer for us... But I whole heartedly agree, testing and evaluating your needs will lead to the right solution...
Side note, I think our 1 and 3/4 is a whole lot closer to conquest's 1.89. Stuff might as well be 2"...
We had a pole barn fire a couple of days ago fought entirely with 2 inch lines. We were flowing at the peak of the fore 800 gpm, 2 lines with the 1 1/4 inch slugs flowing 300 gpm each and another with a combo tip flowing 200 gpm. Knocked down a ton of fire pretty quickly flowing class A foam from the 2 lines flowing 300 gpm.
Again the beauty of the 2 inch showed though immediately the first line off only had 2 guys on it and they were immediately flowing 200 gpm, they were easily able to move the line. Once we established our water supply they went to 300 gpm and as more FFs arrived we added the other 2 lines. Most of the time all of the lines were operated with 2 FFs.
So I went out and retested our lines today, seems we never got our chart updated after we switched to the Conquest. Numbers were a little off. Our 400' 250 GPM 1 3/4" line is 210 PSI PDP and the 250' 160 GPM 1 3/4" line is 90 PSI PDP.
Glad this thread caught my attention.
The difference between Pauls approach and Rays approach boils down to just ONE thing. Paul's approach works very well on compartmentized fires. Rays approach works well on..............ALL fires(structural).Now I've been around long enough to have played in both camps. You use a line that doesnt flow enough you will be chasing all nght. Use the RIGHT line and the Fire goes out and you go home. T.c.
Originally Posted by Fireeaterbob
We are currently testing the 2" hose and are loving it. Getting around 175 gpm with a 200' preconect TFT dual-force nozzle and only pumping 100psi @ the pump. 8lbs heavier(charged) than 1 3/4" per 50' slightly higher nozzle reaction but well worth the added GPM's. Its half the friction loss of 1 3/4"
We just bought new hose and rebuilt/replaced our nozzles. We had old TFT handline nozzles which we rebuilt with the Dual Force Tips on both the 1 3/4 and 2 1/2 lines. Very cost effective move to update the nozzles. We also have 100' trash lines on 2 of our engines and a 3rd 1 3/4 line on our third engine that we went to the Midforce dual pressure nozzles. We also just replace all of our 1 3/4 handline with Mercedes KrakenExo. It has a very low friction loss (6.9 psi @ 100 gmp per 100') and a high kink resistance. The hose is labled as 1 3/4 but has a bowl diameter of 2 1/8. We start the the flow @ 100 psi pump and adjust from there. With this set up, we are flowing between 180-200 gpm.
Wait, what? You're flowing 175 gpm but it's 32 lbs heavier (in 200 ft) and has higher nozzle reaction? So where's the gain over 1.75"? Lower engine pressure and RPM's. So it's harder on the crew but easier on the engine? Seems like there should be more gain to me. We flow 180 from our 200 ft. 1.75" lines at 150 psi and a nozzle reaction of around 70 psi (manageable by 1 FF).
Originally Posted by PCFR 823
We use 2 1/2" for commercial high rise fires, with 75ft lengths. We're considering trying 2 1/2" off the standpipe and the lead length being 2". It's still in the planning stage and we haven't tested this yet. As a side note, we use 1 3/4" for residential high rise also 75ft lengths. Not sure if we're planning to change that to 2" at this time.