There is a "new" concept entering the fire apparatus world, the vacuum tanker. I'm using the term "new", loosely because any of us familiar with the oil field know about vacuum trucks. As a matter of fact, back in my younger days in West Texas, we commandeered vacuum trucks to supply water for large pasture and cotton burr fires.

Vacuum tankers take the tried and tested concept of the vacuum pump to fill and discharge water, and marry it to an NFPA compliant chassis, specifically built for the fire service and can include a fire pump. For many rural departments that already have dwindling memberships and tight budgets, the vacuum tanker can be one way to do more with less.

At a conventional water supply fill site, ( pond, stream, dry hydrant, etc) a department will tie up a pumper, and possibly manpower, which could be used at the fire, to fill tankers. Pumpers are limited in the distance they can be away from the water in order to achieve or maintain a draft. The suction hose connections must remain air tight or you will loose your draft and water supply.

With a vacuum tanker, basically one man can set up and supply water. The limitations of distance to the static water source are only dependent on the amount of hard suction you are able to deploy. Getting water does not depend on airtight connections, and it has been documented that two different sizes of hard suction were duct taped together and water was still able to be provided. Most fill rates average 1250gpm or better.

Utilizing a tanker shuttle? Anyone who uses conventional tankers knows when making turns, or sudden stops, water spills from the overflow. Vacuum tankers are a closed system. there is no spillage. At the dump tank or portable pond, a conventional tanker usually relies on gravity to dump. A few may have a jet dump to speed up the flow of water. But as the level in the water tank drops the pressure of the flow drops, slowing the dump time. A vacuum tanker can overcome this problem. It can be utilized to dump by gravity, or the tank can be pressurized which cuts the dump time almost in half, and the flow rate is not affected.

Depending on how a tanker is configured, Utilizing a conventional tanker in a nurse operation, necessitates using a fire pump to pressure the water to the pumper. A vacuum tanker is able to nurse utilizing the vacuum pump, and even though there may be a fire pump installed, the tank pressurization is usually more efficient.

The cost factor is another consideration smaller departments look at. Surprisingly enough, there is not much difference in the cost of a conventional tanker and a vacuum tanker. Many of the differences come from the options added or removed just as in any apparatus. Also just as in any apparatus, there are many, many different companies which build this type of equipment. This is the one area where a department must be vigilant. Ensure that the builder follows NFPA 1901. The specifications spelled out during the bidding process, and closely examined during the intermediate and final inspections can mean the difference between being able to utilize the apparatus when needed, or constantly having to put it in the shop.

There is no such thing as a "one size fits all" apparatus, and a vacuum tanker will not fit everybody's particular department operations or conditions. But this "new" kid on the block just might make the difference between not having enough resources at the fire, waiting for water to have the resources, or being able to do both.

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My department has had vacuum tanker for ten years now I belive. It's nowhere near a "new" thing in the fire service, although it may be becoming more popular. We love ours, and that we can get water from anywhere. Good post though
Oldman,

The vacuum trucks used where I call home are used for transporting hazardous materials from the oil patch. Like yourself, we've been dealing with suck trucks for years. Santa Barbara had the infamous nitric acid release after a guy driving one of these trucks sucked up the contents of a 55-gallon drum, I believe it was cupric acid or something like that... anyway, the new stuff reacted with the HNO3 (nitric acid) and eventually ripped a longitudinal tear along the bottom of the vacuum truck, spontaneously releasing the trucks entire load onto the freeway. A resulting red cloud of fuming nitric acid spread over the city during late afternoon traffic in the downtown area.

I suppose I should mention that on this particular incident, no one was figuring on a complete tank rupture involving what we thought was a bullet proof vehicle, the "Vacuum Truck". The responders were wrong and learned the important lesson to always face your apparatus pointing away from the incident. You ever see a CHP police cruiser going 90mph backwards?

My point here is that after the incident and before the truck could be moved, the remaining contents had to be removed and the tank tested for residual contents. The "expert" and I use this term very loosely asked a firefighter for his firehose to squirt water into the tank to see if there was any residual materials. The firefighter, so the story goes, said sure... and walked away to notify his Captain what was going on. By the time they got back, the expert, who we will call "Buba", had squirted water into the tank and it did indeed confirm the presence of HNO3 with the release of a vapor cloud that hit the guy in the chest and face. I believe he died within a week due to respiratory and burn complications.

So... this is why I don't 'trust' vacuum trucks. Of course I know that some are used to handle septic systems but that too, in my opinion sucks... :D

So here's some questions:

1. Are you concerned with prior vacuum truck usage?


2. Do you have to test to ensure total decontamination of any hazardous substances from inside or outside the vessel?


If the vessel can be rendered clean and tested to ensure compliance, then you have a pretty sweet truck to help you with water supply delivery and storage. Nice post.

CBz
Sounds like a great improvement. Are they available on just straight tankers, or engine-tankers as well?
I approve this new ambulance.
The apparatus can be configured as straight tankers just for hauling water, or with a fire pump for fire suppression duties as well. Ours is on a four door chassis with a 1000gpm pump and cross lays. For ISO credit it is a tanker, but the setup allows us to vacuum water and fight fire at the same time. The manufacturer is designing a brush truck using the same principle, which aught to be interesting.
I would not advocate using a septic truck or other previous service truck for fire service use. They would not be NFPA compliant and most are not baffled. There are several companies which manufacturer vacuum trucks strictly for fire apparatus use which meet 1901 standards.

Ours has warnings on the tank not to introduce anything into the tank with a pH lower than 4, or higher than 8. Aluminum and acids or caustics can cause a catastrophic failure as you described. Unfortunately, with our legal system today, the liability of converting the old milk or fuel truck to use as a fire service tanker is much too great. The same would apply to a vacuum truck.

Could one be cleaned and certified that it is safe? Probably, but I would look at having a new tank assy. installed on a chassis that I know hadn't had anything else in it. But that's just me.
Maybe a hose attachment which could be placed over the patients face. It would definitely give a new definition to the phrase; "suck face". ;>
Oldman I can answer one of your questions. Because of my oilfield experience around vacume trucks I can consider myself an expert of some sort. You can have them cleaned and certified clean but what most of them will do is just fill them with hot water and let the steam to most the work. When they get the walls and the cieling dripping real good (his terms not mine) then you drain the tanker and jump in there and use the power washer to get the rest of it out of there. After its done they take it and fill it up with clean water drive it around for a bit then dump the water and test the water if its safe for drinking. Then you get a nice little sticker and your clean. Some fuel trucks can not be cleaned because of the potentness of the fuel like jet fuel and the lenght of time they are used hauling it.
Oldman,
Having used vacuum tanks for years in handling livestock I have a few issues. While new machines tend to work great, as the things age you are forever working on seals (on all openings, valves, pump, etc.). While you can usually get the thing working, in an emergency situation how much time is too much. In our area the recent trend is to larger (3000 gal. +) tenders. With a vacuum set up the added weight of a vacuum tank can limit tank size. Just my concerns, might be just the ticket for some Depts.
I find this interesting because we built a few "vacuum induction" units for the fire service; Xenia, OH and Oneida, IL to name a couple. And that was back in the late 80's.
I worked for a company as manufacturing manager for IME, Inc. out of Galva, IL. We were big in the business at the time.
The problem that we had was that the vacuum side of the pump could suck water super fast. The discharge side was the problem. We could not get the gpm up. We started looking at a dual pump set up.
It was interesting. Where I wanted to R and D though was the hi-floatation sprayers. I always thought that they would be great for field fires.
Anyway, this is an interesting topic, since it was being done on a limited scale some 20 plus years ago.
An apparatus that vacuums and discharges simultaneously would almost have to have a dual pump. I know of 4 other vacuum tankers in my area that cannot do both. My truck has a 1000gpm PTO fire pump separate from the vacuum pump which pulls a little over 1200gpm.

The hi-flotation sprayer does sound interesting.
Could you tell us the manufacturer who is designing the brush truck?

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