Why can't scuba tanks be set up like a firefighter's scba?

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The pic is a newer style pack than the ones I currently wear, it has a quick fill mounted near the valve…

Now you have really made me curious. Please let me know if you find a schematic or exploded view. I can see how a two stage pressure reducer would make a lot of sense over a single stage at 4500 PSI, and even more so at 6K.

Do they actually charge these on your back? How, with a compressor on the truck or cascade bottles? Talk about hot fills! :wink:
 
Now you have really made me curious. Please let me know if you find a schematic or exploded view. I can see how a two stage pressure reducer would make a lot of sense over a single stage at 4500 PSI, and even more so at 6K.

Do they actually charge these on your back? How… with a compressor on the truck or cascade bottles? Talk about hot fills! :wink:

Some trucks are equipped with 6000psi cascades that are regulated down to 4500psi and you connect with a whip while it's on ur back. You can also connect 2 packs together in which they would equalize the pressure between the 2. For example if you have a firefighter trapped and low on air you can go in connect a whip and give him a partial fill.

Our hazmat trailer packs are equipped with the ability to fill like that. We never use it unless it is an emergency. Our standard practice is to come out and change out the bottle. All bottles are to be filled in blast container systems. We mako commercial made compressors, cascades, and bottle fill stations. Some station mounted and one mounted in a trailer for mobile operations.

With the new composite bottles they don't get as hot filling them fast as a aluminum or steel scuba cylinder would.

I will see if I can dig up some schematics when I go back on shift next time.
 
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Now you have really made me curious. Please let me know if you find a schematic or exploded view. I can see how a two stage pressure reducer would make a lot of sense over a single stage at 4500 PSI, and even more so at 6K.

Do they actually charge these on your back? How… with a compressor on the truck or cascade bottles? Talk about hot fills! :wink:

Yes, they are most definately charged on the back. These days we are using the MSA mask mount regs, 4500 pound carbon bottles with quick fill built into the pack. We are fortunate enough to have 2 rigs with 6 bottle, 6000psi cascade systems built in. Hot fills are the norm at a working fire. Here is a schematic for the MSA http://s7d9.scene7.com/is/content/minesafetyappliances/AirHawk II Parts List - EN
You'll have to scroll down some to get to where the first stage is depicted. The only piece that is coupled to the valve is the low air bell. I mistakenly called the line from the first to second stages high pressure. It is a reduced pressure line. You'll have to excuse those of us that started out with belt mount regs, compared to the old corrugated elephant snout, the mask mount hoses are high pressure.

One thing that I liked about the old belt mount regs was that if you experienced free flow, whether due to icing or submersion, one could simply close the main valve on the reg and sip air through the bypass valve. It's not impossible to do with the mask mount regs, but the act of closing the main on the second stage has the double duty of releasing it from the facepiece so it's less convenient.
 
A few years have passed, but this discussion is not dependent on dates. It is still valid.
This discussion was referenced, hence I will comment this. Bring back the dead!
How would you route your inflator hose so it's secure while still allowing you to raise your inflator?
We do not do such a thing. The wing has a rear dump.
What about the octo and primary? Think about reg recoveries and air shares.
Neck bungee has solved this since decades ago. Learn from UK sump divers.
OR: grab the 1st stage (easy!) and follow the hose.
There's also the issue of setting your unit down on the ground or on the boat bench.
That is partially true!
Don't the fire fighters face the same issue???
One could also say it's just as easy to reach your valve over your shoulder as it is behind your back
Please do 30 minutes of valve feathering and then reiterate your opinion.
 
A few years have passed, but this discussion is not dependent on dates. It is still valid.
This discussion was referenced, hence I will comment this. Bring back the dead!

We do not do such a thing. The wing has a rear dump.

Neck bungee has solved this since decades ago. Learn from UK sump divers.
OR: grab the 1st stage (easy!) and follow the hose.

That is partially true!
Don't the fire fighters face the same issue???

Please do 30 minutes of valve feathering and then reiterate your opinion.
Oh boy, I'm a different person now and not really in the mood.
Go for it and let us see pictures.

I would be humored to see the hose routing. Also a video of the firefighter-inspired pack drop of a solid wall tank +scuba unit onto the pavement from a standing position.
 
The tanks on a firefighting scba are shorter, much lighter and usually have a rubber bumper on the valve assembly, and no tank mounted regulator to worry about. "Dropping the pack" would be considered abusive to equipment, but pack removal while on air to get through openings is something that is commonly practiced.
 
One of the things I love about my SCBA versus SCUBA setups is the hose routing. On ours (last gen Scott 4500s) the hose for the mask mounted regulator (MMR) come off the primary regulator in the small of my back, is routed up the frame under the bottle, and then into the left shoulder strap and comes out of the strap about the nipple line. There is only about 18-20" of exposed hose before the MMR, and one end is firmly attached to a spot I can easily reach in pretty much any position. Our Personal Alert Safety System (PASS, equivalent to an SPG with some other features) is mounted on the right shoulder strap and while it swivels for viewing, it's not on a hose where it can go anywhere. The transfill hose, our equivalent of a secondary reg, is in a pouch on the right hip and unless you open said pouch, it's never in the way. All of this stuff is designed to be manipulated with thick gloves on in zero visibility.
 
You see a few people using inverted twins here. Often it’s because they have limited shoulder mobility for whatever reason like surgery …

Usually with a halo so you can drop them.

There is a pic of someone using such a setup in this thread Anti-snag valve-down tank mounting?
 

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