A recent article about a Lake County, Florida fire truck accidentally laying 1200 feet of firehose down the middle of the Florida Turnpike and causing damage to a number of cars made me want to post about the old days when I still did that sort of thing.

The hose that runs from the fire hydrant to the fire truck is called supply line. Most supply line is 3 inches or more in diameter, and in Central Florida, it’s usually 5 inches. (Orlando uses 4 inch, but that is because they typically have fire hydrants that are close together).

First, a bit of engineering.

The reason for this is hydrodynamics and friction loss. The average water main pressure is about 65 psi. At 1,000 gallons per minute, a 3 inch hose loses 80 pounds of pressure every 100 feet of hose length due to friction between the moving water and the hose itself, while a 4 inch diameter hose loses 20 pounds of pressure, and a 5 inch hose loses only 8 pounds. That means, if you want longer hose lays with high flow, the larger the diameter of your supply line, the better.

There is a lot of math involved in being the driver of a fire engine. You need to be able to calculate your friction losses in your head, rapidly, and remember that the lives of the guys in the burning building depend on you getting it correct. When you are flowing 2,000 gallons per minute through half a dozen different hose lines a 2 in the morning at a burning strip mall isn’t the time to realize that you are math deficient.

5 inch supply line has what is called a “sexless coupling” meaning that there is no male or female end, the couplings are interchangeable. This allows you to start laying from either the fire to the hydrant, called a reverse lay, or from the hydrant to the fire, called a forward lay. There are advantages and disadvantages to both, but we won’t talk about that in this post.

My fire truck carried 1200 feet of 5 inch diameter supply line. That means with standard hydrant pressure, I could get a bit more than 800 gallons per minute into my engine without having to put another fire engine at the hydrant to boost pressure.

The problem with this is twofold:

  • 5 inch hose is heavy. Each 100 foot section weighs a bit more than 100 pounds without water in it. Filled with water, that increases to over 1,000 pounds.
  • 5 inch hose is bulky. The hose itself lays flat, but the couplings are a pain. The hose has to be loaded on the truck in a specific way, or it won’t come out of the truck correctly.

In Practice:

Both of these issues mean that 5 inch is a pain in the ass. It’s worth it, but that is not much consolation when you have to lay and reload 1200 feet of it. Anyhow, if loaded correctly, that hose comes out of the truck like a scalded dog. Like so:

I sympathize with the guys that this happened to. I once laid all 1200 feet of my supply line without meaning to when I was on the way to a large multi alarm fire. We hit a bump, the hose began laying out, and I dumped all 1200 feet in the middle of the road.

There was another time that the water department had removed a hydrant without telling the fire department. I arrived at a fire at 2 o’clock in the morning with the assignment of “secure the water supply.” I decided to do what is called a reverse lay.

So I began laying my supply hose at the fire, and headed to where I thought the closest hydrant was. 1,000 feet later, I arrived at where the hydrant was (or so I thought) and it was no longer there. After the fire was out, the other guys on the engine were not happy with me at all as we loaded all thousand pounds of hose back onto the truck.

The reason for that, is the hose is loaded by the driver backing over the hose as firefighters standing on the back of the truck lift it and load it back on the truck. The driver doesn’t do a thing but drive, the firefighters load the hose. I wasn’t a popular guy that night…

For those who are interested, the amount of hose and other equipment carried on the engine I was assigned to for the last six years of my career as a firefighter was pretty impressive. We had:

  • 1200 feet of 5 inch supply line
  • 300 feet of 3 inch supply line
  • a single 30 foot piece of 5 inch supply line in the side running board
  • a 250 foot length of 2 1/2 inch line preconnected to a smooth bore nozzle (cross lay)
  • a 300 foot piece of 2 1/2 inch line preconnected to a gated wye
  • a pair of 1 3/4 inch line that were 200 feet each, with nozzles connected to them (cross lays)
  • a 100 foot long 1 3/4 inch “trash line” on the front bumper
  • another 200 feet of 2 1/2 inch line, and 300 feet of 1 3/4 inch line in the storage compartments.
  • a “high rise pack” with another 200 feet of 1 3/4 inch hose in it.

That comes to 4,000 feet of hose. Plus all of the connectors, hose tools, breathing apparatus, spare air bottles, medical equipment, thermal cameras, 100 gallons of various types of foam, a set of hydraulic rescue tools, air tools, hand tools, flashlights, a gasoline powered fan, a power saw, extension cords, 2 chain saws, 6 axes, a set of pneumatic lift bags, 2 cases of Gatoraide, 2 boxes of energy bars, and a dozen other tools. The truck itself has a 1500 gallon per minute pump, a 10 kw generator, and 1,000 gallons of firefighting water onboard. In all, there were more than 10,000 pounds of equipment and supplies on that truck.

I loved driving and working off of that engine. I did everything on that truck- I rode as firefighter, paramedic, driver, and even as the officer in charge. There are times that I miss doing it. Life was easier and less complicated then. All I had to do was put the wet stuff on the red stuff.

Categories: Glory Days


AZFloyd · December 2, 2023 at 8:25 am

The most interesting thing I have read in a while. More blog post like this, please. I live in downtown Boise. Engine #5 and Ladder #5 are always making runs. On the ladder engine is a guy who steers the rear wheels. As a former soldier, I notice how well kept the engines are kept and that they keep thier boots by the engines.

SmileyFtW · December 2, 2023 at 10:06 am

Posts like this are such a joy to read. I know virtually nothing about some of the topics you know intimately and describe so well… thanks!

Pat H. Bowman · December 2, 2023 at 10:59 am

Ah, 5″ hose. Back in the mid ’80s, I was a volunteer firefighter in a small rural village in upstate NY. We were by far the smallest department in the least populated district in the county. At that time, the entire county was standardized on 3″ supply lines and 1,000 GPM pumps. They would lay in one or two 3″ and get to work. Sometime around ’83 or ’84, we took delivery of a new engine that carried not only 5″ hose, but 2000′ of it, and had a 2,000 GPM pump. The entire county made fun of us.

So much so, that we got called in for a mutual aid call for a structure fire at a neighboring district. By the time we got there, they had it well under control, but their captain though it would be funny to get us to lay out nearly 1,500′ of 5″ from way down the hill. We did, and right as our engine pulled up, he said, “Never mind, we got it out.” They all had a good laugh at us while we spent the next few hours in the dark and cold picking up the hose.

A year or so later, I remember being in a structural fire fighting course at the county training grounds. Legendary instructor “Packi” was getting into friction losses of supply lines, a topic that was unknown in those parts at that time. He said, “You guys all like to make fun of Honeoye Falls for carrying 5″ hose, but let me run some numbers for you.” Man, did we ever feel vindicated! I don’t think it took more than about 5 years and the entire county had switched to 5″.

You’re right, though, picking up 5″ sucks. Having to lay it back out and pick it up again because some schmuck stacked it wrong is even worse. That same schmuck also charged a 1 3/4″ cross lay while it was still in the bed. Trying to get 200′ of 1 3/4″ that’s full of water out and then put it back is one of life’s little joys. He was so popular, they made him a LT.

Those were good days.

SoCoRuss · December 2, 2023 at 1:36 pm

You my brother have had a very diverse and interesting life.

Vlad · December 2, 2023 at 1:39 pm

Ahh yes, the old days of being a hose dragger medic.
Unfortunately I remember them well.
(Just yesterday I fell asleep on the couch with the TV on. Some tone on the TV sounded just like the dispatch tone and I jumped ready to head to the door. I’ve been retired for 13 fucking years!!)

I too was a FF that could move up to the front seats and play water or radio jockey.
It was much easier in the old days whey you could ride on the tailboard and hump hose. A couple of accidents (not in my dept but somewhere in the US) took that option away.
We had 5” that had male/female couplings like the attack lines. Since we couldn’t ride and load, you broke all the couplings, walked out the water and dragged the sections back to the truck. What fun! 🙄

Nothing makes the ED staff cheer up like bringing in a chest pain pt while you’re wearing the bunkers/boots you had on in the fire and tracking soot and wet insulation around.
Makes it stink like a house fire for an hour!

Grumpy51 · December 2, 2023 at 3:46 pm

LOVE ME SOME LDH (large-diameter hose)!! SE TX, early 80s. C-shifter, 5″ hose ALL the time!! That speed is about right too (to prevent the coupling from bouncing off the pavement).

Racking it was another story (as you stated above)…….

Anonymous · December 3, 2023 at 4:07 am

Details omitted for persec, but in Marion county FL there was a rural fire station that was closed for whatever reason. Friend is a former paramedic with firefighters, now nurse. I asked them could I reopen it as a volunteer station, given that the equipment was already purchased and present. They said there is no such thing as volunteer firefighters anymore, the station leader was a government paid position, and government says only government allows government to declare who shall fight fires.

Anonymous · December 3, 2023 at 4:18 am

Rereading that, “paramedic” is probably incorrect, what I know is they rode around in an ambulance, before they became a nurse. But I don’t want to single them out in blog-public.

Wild, wild west · December 3, 2023 at 8:47 am

Years ago, 1970’s, I was a volunteer fireman in a small town in Missouri, and very small town at that, less than a thousand people. Our two trucks were equipped with hose reels on each side and 3″ hose in the bed with a couple of large diameter rigid hoses on the side to hook up to hydrants if one was close enough. In those days, there was little to no training, and we thought hydraulics were something tractors used. You basically showed up and did the best you could with those who showed up, and quite often by the time the truck made it to the fire, the structure would be fully involved and the best you could do was pour water on the adjacent houses to keep them from burning down too. If the fire was very far outside the city limits, forget it.

Thus it was late one night we got called out and arrived at a house fire to find the roof and walls already collapsing, obviously a total loss and nothing much to be done about it. But we poured water on the blaze, put it out and stuck around for a while to check for hot spots. Then we put the truck up and
adjourned to the local beer joint.

Several beers later, meeting adjourned and a few of us decided to swing by the fire on our way home to check for hot spots and sure enough, there was a small one in one corner. Now what? We really didn’t want to go get the fire truck, that would have been a lot of work for a few embers and we probably shouldn’t have been driving our own cars, let alone a fire truck. So, we formed a circle, unzipped our pants and put the embers out with our own personal equipment, some of it probably 5″ hose, only not in diameter……

And small towns being small towns, the next morning, the story was all up and down Main Street and the neighbor who saw us was raising hell with what passed for a city council and the mayor actually said he was gonna fire us. Fire us? How you gonna fire somebody who ain’t getting paid in the first place? And then what ya gonna do for a fire department? Everybody who wasn’t there said they’d all quit if we got thrown off the department, so it didn’t take long for that to blow over and we enjoyed the notoriety for quite a while afterwards.

Paulb · December 3, 2023 at 6:08 pm

It’s funny, I just looked and Goodyear doesn’t list the Goodyear 6″ collapsible bunkering hose we use for ship-to-ship fuel transfers in the 3rd world in unprotected water. They’re not legal to use in the US, as they don’t have a conducting wire for reinforcement and static electricity management. The weight is about the same, 100lbs + the flanges, which are about 80lbs each being aluminum (not legal for use in the US again, we require all steel) with a steel ring for inch and a quarter bolts. Good for 225psi but we’d limit them to 60psi.
are the 5″ suction hoses collapsible, or wire-reinforced? I wouldn’t like to think about a car crossing one. Drive the struts through the hood of the car, lol.

    Divemedic · December 3, 2023 at 7:19 pm

    Collapsible. Here is a picture. The top, yellow one, is the one with the sexless coupling. (The coupling is called a Storz coupling.):

    The hose is certified for 450 psi. Supply hose is tested each year at 200 psi.

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