Cafs ?

[LeatherHed4Life]

I know a little bit about CAFS but Im wondering about flow through a 1" booster line.

Is the booster capable of flowing more than an 1 3/4 line? Is there a reason dept's use cafs with an 1 3/4 vs a booster line?


Thanks

[The nots so new FNG]

I know a little bit about CAFS but Im wondering about flow through a 1" booster line.

Is the booster capable of flowing more than an 1 3/4 line? Is there a reason dept's use cafs with an 1 3/4 vs a booster line?


Thanks

First - yes, a 1" line can flow more than a 1 3/4 if you pump it at a high enough pressure and the 1 3/4 at a low enough pressure. That said, for any given pressure in both lines, you get more from the 1 3/4 than the 1".

Second - for why we use 1 3/4 not booster lines. We always plan for losing CAFS which means either simple foam solution or plain water. I don't want to be interior on a structure fire with simple water in a booster line. This is also true for fire flow calculations. I asked about this soon after I got on and the answer was yes, CAFS can multiply the effectiveness of water but you plan for not having it. If you go with the basic water flows, you just put the fire out that much quicker with that much less water damage using CAFS.

[LeatherHed4Life]

First - yes, a 1" line can flow more than a 1 3/4 if you pump it at a high enough pressure and the 1 3/4 at a low enough pressure. That said, for any given pressure in both lines, you get more from the 1 3/4 than the 1".

Second - for why we use 1 3/4 not booster lines. We always plan for losing CAFS which means either simple foam solution or plain water. I don't want to be interior on a structure fire with simple water in a booster line. This is also true for fire flow calculations. I asked about this soon after I got on and the answer was yes, CAFS can multiply the effectiveness of water but you plan for not having it. If you go with the basic water flows, you just put the fire out that much quicker with that much less water damage using CAFS.

so the CAFS can be operated at different line pressures?

Im talking about a standalone system with no pump and approx 90 gal tank. will a booster line suffice for interior attack?

the obvious answer is no, but im looking for additional info that could prove otherwise

[The nots so new FNG]

so the CAFS can be operated at different line pressures?

Im talking about a standalone system with no pump and approx 90 gal tank. will a booster line suffice for interior attack?

the obvious answer is no, but im looking for additional info that could prove otherwise

First, yes CAFS can run different pressures. We have 50psi smoothbores and 125psi combo nozzles we have run CAFS with. Most of the time its the 125psi combo's we use.

As for the second part, we actually have one of these as well on our heavy rescue. Its a 100 gal water/foam premix tank with a small 6000psi gas bottle/reg. Attached to is is 150' of cloth 1" line and a smooth bore nozzle. The idea is that if our heavy rescue rolls up to an MVA with fire before a pumper, it can do something to protect any victims. (and actually, 100 gallons of CAFS can do quite a bit if used properly). I believe it uses a 75-80gpm nozzle so you have a little over a minutes worth of CAFS.

I would NOT use this for interior attack unless it was a last ditch effort to try and make a save (or buy time to make said save). There simply isn't enough foam/water backing you up to do it safely. Our attack engines booster tanks are 1000 gal or 10x this.

[neiowa]

First, yes CAFS can run different pressures. We have 50psi smoothbores and 125psi combo nozzles we have run CAFS with. Most of the time its the 125psi combo's we use.

As for the second part, we actually have one of these as well on our heavy rescue. Its a 100 gal water/foam premix tank with a small 6000psi gas bottle/reg. Attached to is is 150' of cloth 1" line and a smooth bore nozzle. The idea is that if our heavy rescue rolls up to an MVA with fire before a pumper, it can do something to protect any victims. (and actually, 100 gallons of CAFS can do quite a bit if used properly). I believe it uses a 75-80gpm nozzle so you have a little over a minutes worth of CAFS.

I would NOT use this for interior attack unless it was a last ditch effort to try and make a save (or buy time to make said save). There simply isn't enough foam/water backing you up to do it safely. Our attack engines booster tanks are 1000 gal or 10x this.

You using a fog nozzle with CAFS?

[The nots so new FNG]

You using a fog nozzle with CAFS?

Yep.... Automatic nozzles that unscrew for a slug tip though we also use them as straight stream nozzles.

Not my call so it is what it is.

I should add the skid mount CAFS unit has a differnt smooth bore nozzle on it. Just our front line pumpers use the combo nozzles.

[neiowa]

Order a 15/16" tip @ $60 for the shutoff and you've got the industry std nozzle for dry CAFS.

The automatic nozzle/tip likely will make a fair chock.

[KB1OEV]

Its a 100 gal water/foam premix tank with a small 6000psi gas bottle/reg.

According to the instructors in a foam class I took recently, when foam is mixed with water in a tank, it lasts for 24 hours before it begins to break down and become less effective.

You might get better results by keeping a jug of foam next to the tank and dumping it in just before its to be used. Should only take a few seconds to do.

[The nots so new FNG]

According to the instructors in a foam class I took recently, when foam is mixed with water in a tank, it lasts for 24 hours before it begins to break down and become less effective.

You might get better results by keeping a jug of foam next to the tank and dumping it in just before its to be used. Should only take a few seconds to do.

In our case - we are following the manufacturers directions as well. I am guessing we are using a differnent concentrate that doesn't break down like the one you describe from your foam class. I don't have the details so I can only speculate.

As for the 2nd suggestion - its a pressure vessel so opening the lid isn't as straightforward as your suggest. On a rapid intervention device, speed is important and futzing with this for a few minutes negates its value. The lid is not quick to open/close.