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What is the longest and still safe length should you have on a 1 3/4 attack line ???

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In my humble opinion, it depends on the type of nozzle you're using and the desired GPM output. 

100 psi turbo jet   ---   180 gpm--     15/16 tip 180 gpm

Shareef Abdu Nur said:

In my humble opinion, it depends on the type of nozzle you're using and the desired GPM output. 

Greg, I would not exceed six lengths, 300 feet either. The other training evolution I would recommend would be to grab a few in-line gauges and place them on your pre-connects every 50 feet if possible and at least every 100 feet to see what your actual friction losses are in those sections. You might be very surprised by what you find. Of course the simplest way is to put one in line gauge at the discharge from the hose bed and one in line gauge at the nozzle then you can get the overall friction loss for the entire stretch. And I would do this for every pre-connect on a regular basis, calculating friction loss is like reading fiction it's interesting but not very useful. Measuring friction loss is extremely useful and provides you with a real-world understanding of what you are delivering to that nozzle.

I go with 6 lengths as well, I have however heard of some companies out there preaching the use of 600 and even 800ft 1 3/4 lines.

My argument to this is that sure your engine may pump that 1 line but what about the 2nd line? What about the RIT line? No way your engine can pump those lines to there optimum operating capacity.

Whenever we go over the 300 ft length we utilize a 3 inch leader line with a water thief (1 3inch discharge and two 1 1/2 discharges) This give you the ability to pump more efficiently, pump multiple lines, and have the option to extend it with more 3 inch or add a 2 1/2, or add a 3 inch line for our blitz fire or portable master stream.

This works well for my department, and it creates options so your not backed into a corner with only one choice.

Thanks Chief..

Bobby Halton said:

Greg, I would not exceed six lengths, 300 feet either. The other training evolution I would recommend would be to grab a few in-line gauges and place them on your pre-connects every 50 feet if possible and at least every 100 feet to see what your actual friction losses are in those sections. You might be very surprised by what you find. Of course the simplest way is to put one in line gauge at the discharge from the hose bed and one in line gauge at the nozzle then you can get the overall friction loss for the entire stretch. And I would do this for every pre-connect on a regular basis, calculating friction loss is like reading fiction it's interesting but not very useful. Measuring friction loss is extremely useful and provides you with a real-world understanding of what you are delivering to that nozzle.

I think it really boils down to is what your department needs are and what are your fuel loads?

I'm in a rural department and we run 150' cross lays and blitz line as this allows us to gain access to over 75% of our calls.  If we need more, we just extend the line out. Usually we are not concerned with friction loss as our department uses variable gallonage noozles. 

I'm sure there are some engineers or chauffers out their that just cringed at me.  But if we need the gallonage....its time to go to a 2 1/2 handline.  Our working pressures depend on the fire and conditions, but we usually run about 125 psi on a 1.5 to 1.75 in handline stretch out at 150ft. 

Ive always been taught 6 (300ft) and our Apparatus utililize 200ft 1 3/4 preconnect with a Solidbore nozzle (15/16) If we need to add the 2 1/2 will be used.

I concur 300 feet. Question has to be raised, why would you need anything longer? 150feet max working length on interior, longer then its 2.5 or master streams.

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