What Size and Length are Your Preconnects

Replies to This Discussion

Permalink Reply by Shareef Abdu Nur on December 13, 2008 at 5:33am

Our Engines carry 2-200 ft 1.75" crosslays(SB and fog), 1-150 ft 1.75" bumper trash line(fog), 1-250 ft 2.5"(SB)rear, 1-250 ft 1.75"(SB)rear. Our preconnects are based on our response area and we have never really had a problem stretching short. Our truck carries 1-200 ft 2.5" SB crosslay and 2-1.75" fog 200 ft.

Permalink Reply by Michael Bricault (ret) on December 13, 2008 at 2:10pm

-200 ft., 200 ft., ..... Ever wonder why most of the respondents are saying that their pre-connects are 200' in length? The answer is so simple that most of us never bother to spend the time to learn why. Our predecessors figured it out in the past, it works and we take it for granted. It is hydraulics.
-Once in a great while, someone will make the mistake of wanting to experiment with this stuff without learning the principles or lessons of the past, such as having an 1 3/4 hose line that is LONGER THAN 200 FEET.
-The hydraulics DO NOT WORK.
-The Cincinnati FD had to learn this lesson the hard way after one of their members, Firefighter Oscar Armstrong lost his life while operating a pre-connected 1 3/4 hose 350' long.
-To the admirable credit of the CFD, they were able to perform an internal investigation into the circumstances of FFR. Armstrong's death that they later made public in an effort to educate other FD's so as to prevent future deaths.
-One of the main contributing factors in the death of our Brother was discovered by the CFD to be the excessive length of the pre-connected 1 3/4 hose he was operating.
-The simple facts are that hydraulically, the 1 3/4 hose is not effective in lengths OVER 200 FEET. The stream MAY APPEAR adequate HOWEVER, there are simply not enough GPMs to overcome BTUs and raising the engine pressure is counterproductive above 135 PSI in conjunction with a typical fog nozzle. I would refer any debate on this to Andy Fredrick's in depth studies on the subject.
-Lastly, the CFD report, detailing this information, can be obtained on line. If you can't find it drop me a line and I'll email you a copy.
-If firefighters need more than 200' they should be stretching the 2 1/2" line. If they give the excuse that the 2 1/2 requires more time or manpower to stretch than they clearly need more practice to stretch and advance the line with two members.
-The rule of thumb is stretch the 2 1/2 if the fire has control of more than two residential sized rooms, if the fire is in a commercial occupancy, if the fire is of an undetermined size and location with significant smoke showing, and if the fire is below grade.
-Stay safe.

Permalink Reply by Ray McCormack on December 13, 2008 at 10:02pm

Michael - While it is always nice to keep operating pressures down, using 200' of 1 3/4 as a "standard" may or may not be based solely on hydraulics as much as hosebed depth, property setbacks and standard home dimemsions..We use 300' of 1 3/4 as our standard bed and pressures are not a problem. At the fatal fire 350' of 1 3/4 was stretched (which was an excessive amount of hose for that fire) it was not fully flaked out and it became a kinking problem. While water was being called for the hoseline was advanced into the house DRY and then the house flashed over. Firefigfhters need to know when to shorten stretches not just lengthen them.

Permalink Reply by Doug Ott on December 13, 2008 at 10:27pm

We have:
1 150' of 1-3/4" with a TFT fog
2 200' of 1-3/4" with an Akron combination
3 200' of 2" with larger TFT fog
4 100' of 1-3/4" trash line with a TFT fog (quints have it in the front bumper, engines have them in a trough on the side)

It is based on our response areas. Things get tricky with houses that are set further off the street and the driveway is too small. But that is a small percentage of our homes.
This has worked out well for us when we do have fires. A few of the drivers in our department (myself included) are in the habit of having an extra roll of 50' of 1-3/4" in a compartment and it has come in handy for extending a preconnect on occasion. We have 100' of 2" as a hotel pack and that is useful if we need to extend the 2" preconnect. Also, on some larger buildings we have had to stretch some 3" hose with a gated wye and use one of the lines off of that.

Permalink Reply by Michael Bricault (ret) on December 13, 2008 at 11:50pm

-Ray, I agree that lengths of the 1.75" hose are an issue and in some instances firefighters may be deficient in awareness regarding decreasing the length needed.
-After your post I went back and re-read the reports that I have on the issues surrounding the tragic circumstances of Oscar Armstrong and the CFD and you are correct that kinking was listed as a possible contributing factor in the eventual outcome. However, as I stated originally, as per the reports generated by the CFD, one of the main overall contributing factors in the outcome was the length of the 1.75" line, of which you and I and the CFD agree was excessive and would not allow for adequate, proper fire flow.
-Having read material by Andy Fredrick, the City of Albuquerque FD conducted an extensive evaluation concerning flows, nozzles, hose lengths and the different apparatus in service. The purpose was not to prove or disprove Andy's work but rather to validate his findings to our own people and get our people on board with the ideas Andy was espousing.
-Our findings are that 1.75" hose in conjunction with a TFT fog nozzle is operating at max capacity at 130 PSI/100 GPM and that lengths or pressures greater than these begin to produce a paradoxical effect with decreasing returns.
-With respect to your experience and observations with the 300 ft lengths of 1.75 hose I will respectfully concede the matter that we disagree on the practicality of operating 1.75" lines greater than 200'.
-Stay safe

Permalink Reply by Ray McCormack on December 14, 2008 at 11:06am

Michael Bricault Stated -After your post I went back and re-read the reports that I have on the issues surrounding the tragic circumstances of Oscar Armstrong and the CFD and you are correct that kinking was listed as a possible contributing factor in the eventual outcome. However, as I stated originally, as per the reports generated by the CFD, one of the main overall contributing factors in the outcome was the length of the 1.75" line, of which you and I and the CFD agree was excessive and would not allow for adequate, proper fire flow.
I only stated that it was to long of a stretch I never said it was it would not supply the proper flow.
The biggest problem for any engine company is to go into a home with a dry and untested hoseline.
We use smooth bore nozzles and max out our 1 3/4 lines at six lengths.

Permalink Reply by Art Bloomer on December 14, 2008 at 12:31pm

Ray,

I have to agree with your concept that you can work with up to 300' of 1 3/4" line, as long as you are using a straight bore nozzle. With the lower pressure requirement on 40 to 50 PSI to get the proper flow, that is about the max you can pull that size line. I have no faith any longer in most fog nozzles, in particular the "automatic" variety. If that sliding venturi gets hung up, a flow of only 50 GPm looks good and has decent reach, just far from enough water to even scare the fire a little bit. Besides the fact that most fog nobs need at least 100 PSI at the tip to get the rated flow. That equates to too much pressure at the engine. As you state....check your flow and pattern at the door, and you will know that at least you are starting out good. All members should chase those kinks....your brothers are on the end of that line!!!

KTF

Art B.

Permalink Reply by Michael Bricault (ret) on December 14, 2008 at 12:50pm

-Art, I agree with your thoughts regarding fog nozzles; I hate the damn things. The engine in my house has one cross lay outfitted with a fog, the other cross lay has a solid bore. Generally the line stretched is the solid bore.
-I couldn't agree more with the comments about stretching and flaking techniques, not chasing kinks, etc.... Seems like there is a lot of poor hose handling and a lack of supportive work taking place in favor of competition for the nozzle. Far to many young firefighters are relying on higher engine pressures to do the support work like blowing out kinks instead of performing proper stretches and chasing kinks.
-And yes.... remember that its our Brothers at the end of that line. Supporting them is a priority.
-Just a few thoughts on hose work from a Truckie.
-Stay safe

Permalink Reply by Wayne Benner Jr on December 14, 2008 at 2:25pm

I was just discussing our preconnects which I have posted earlier. The discussion was adding solid bores to our arsonal. A Sr member said he didnt want them on because they would destroy possible evidance for investigation. How on earth is this our problem as suppression. When does commen sense come into play. Ive got a fight on my hands on changing our preconnects to solid bore keeping the fogs on our trash line.
Im waiting for someone to suggest bring back the hardy gun on a booster line for interior ops :L)

Wayne

Michael Bricault said:

-Art, I agree with your thoughts regarding fog nozzles; I hate the damn things. The engine in my house has one cross lay outfitted with a fog, the other cross lay has a solid bore. Generally the line stretched is the solid bore.
-I couldn't agree more with the comments about stretching and flaking techniques, not chasing kinks, etc.... Seems like there is a lot of poor hose handling and a lack of supportive work taking place in favor of competition for the nozzle. Far to many young firefighters are relying on higher engine pressures to do the support work like blowing out kinks instead of performing proper stretches and chasing kinks.
-And yes.... remember that its our Brothers at the end of that line. Supporting them is a priority.
-Just a few thoughts on hose work from a Truckie.
-Stay safe

Permalink Reply by Ray McCormack on December 15, 2008 at 9:46am

I like a fog on a trash line. You do have a problem on your hands Wayne. I wonder what other gems have come from this Sr. members mouth. Somewhere along the line he and a lot of the fire service have lost touch with what is important. FIRE EXTINGUISHMENT! Yes, it is that simple. Bring a few SB's in and do some testing side by side inside a house.

Permalink Reply by Joseph R Polenzani on December 15, 2008 at 11:05am

Amen, Ray.

Not to take us too far off-course, but...I see a lot of departments here using the break apart SB/fog nozzles. My question is: How many times do they actually get "broken apart" at a fire? Unless the officer puts the fog tip in his pocket at the beginning of the shift (or tosses it in a corner...), it's probably going to stay on the end of the hose all day.

We see the same thing with our stacked tips on the 2 1/2". People pull the big line and then leave the 1" tip in place (210 gpm), instead of going up to the 1 1/4" (325 gpm-ish). When I was on an engine company, I'd throw the two smallest tips into the glove box or engineer's compartment and it'd usually take the other shifts a few weeks to notice and put them back. Just an idea...

FWIW, we run:

Crosslays:
150' 1.75" TFT
200' 1.75" 7/8" or 15/16" SB

Rear Preconnects:
250' 1.75" TFT
400' 2.5" 1" - 1.25" SB stack

Bumper:
100' - 150' 1.75" TFT

All of our rigs (including the ladders and towers) have pumps, tanks, 4" supply hose, and preconnects. The preconnects vary a little on the towers, due to design limitations.

The 200' seems to work well for most our SFDs, where we can park on the street or in the driveway and go in the front. However, we're getting a lot of monster (4,000 - 10,000 sf) homes now, which has forced us to rethink our standard stretch.

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