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UTD Z-side mount with isolatable manifold

Discussion in 'Sidemount Diving' started by eelnoraa, Jul 29, 2013.

  1. mathauck0814

    mathauck0814 Assistant Instructor

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    Jim - that's all fine and well, but largely incompatible with the UTD system here. You don't get a choice of hose configurations and the wing won't support steel tanks of any size. I agree that if I were to sidemount, I'd go with a system more configurable a la your own. The UTD system with its soft manifold is something else entirely.
     
  2. DevonDiver

    DevonDiver N/A

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    I see little need for the manifold system, unless you are restricted by adherence to UTD's dogma.

    The positive: It provides access to gas, even after shut-down.

    The caveat: Sidemount divers are trained to 'feather breath' (at all levels) and/or 'reg swap' (at technical levels) to access gas in a shut-down/malfunctioned regulator.

    The negatives:

    (1) Big block of metal at the top of your spine (why there??!!?? why not in front, where it is accessible to the diver?!?)
    (2) A multitude of addition failure points within a life-support system.
    (3) Loss of true redundancy.
    (4) Excessive cost.
     
    tracydr and ajtoady like this.
  3. TSandM

    TSandM Missed and loved by many. Rest in Peace

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    You have to understand the REASON for the Z-system. Andrew wanted to build a system that would permit easy mixed-team diving, utilizing essentially the same protocols as the basic DIR ideas. This means a diver is always breathing the long hose, and donates the long hose. In most of the usual ways of setting up sidemount, half the time the diver is NOT breathing the regulator he would donate. So the initial UTD sidemount setup involved a non-isolatable, low pressure manifold, which has a great many problems. Not only do you have a lot of connections behind your back, if ANYTHING downstream of the manifold fails open, the only way to stop the loss of gas is to disconnect BOTH QCs, and fumble for a spare regulator somewhere.

    The isolatable manifold allows you to continue using one of your two standard regulators, and you can turn off the valve to the other tank, so you're not really much worse off than you are in a "standard" sidemount setup. You still have the IP problem, which requires that you keep the tank you are not breathing turned off, so that in the event of a gas loss emergency, you could be shutting the isolator, shutting the offending tank, AND turning on the tank you need to use, which is two more steps than in "traditional" sidemount.

    It's better than the original, but you have to decide whether the ability to maintain the long hose/bungied backup system with the reflex long hose donation is worth the additional complication and additional expense.
     
    tracydr likes this.
  4. DevonDiver

    DevonDiver N/A

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    Some people could interpret this to mean that UTD don't have a protocol for air-sharing during deco :wink:

    Of course, we know they do. We know it's quite feasible to deal with air-sharing when the long hose isn't being breathed.

    I'm not UTD trained, do they specify a 'breakaway' or 'cutaway' clip on the long hose for the purpose/provision/capability of air-sharing back-gas during deco (when the reg is clipped off/not in the mouth)?

    Or a protocol for response if a team-mate incorrectly gas switches and/or shows signs of ox-tox? Other agencies tend to recommend a 'rip-and-replace' response in that scenario. So...long-hose air donation from the clip..

    If my prediction is true, I see little compelling reason why they couldn't simply modify a mixed-team response based on existing air-sharing deco protocols, rather than the decidedly un-K.I.S.S. solution that they opted for..

    In context to the OP's original question - opt for the enormously expensive 'Z-manifold' if you, or those you dive with, have no knowledge of deco air-sharing procedures; or no capacity to perform them... and/or are unwilling or unable to use a break-away stowage clip on the long-hose.
     
  5. HenrikBP

    HenrikBP Solo Diver

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    I believe you would always donate what you are breathing, so if on a deco bottle, you would donate the deco reg from your mouth. The donor would go onto back gas via necklace back-up reg.
     
  6. DevonDiver

    DevonDiver N/A

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    So they don't donate from the long-hose? :wink: Say it ain't so...

    What's the difference between donating from the mouth with a 40" deco hose from the left-side...and a 40" sidemount hose from the left-side?
     
  7. eelnoraa

    eelnoraa DIR Practitioner

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    I think Henrick is right, donor donate what he/she is breathing, long hose or deco reg, then donor goes on to backgas. I think the difference is with backmount DIR, the back gas is on all the time, so donor just pick up the necklace, gas supply is there already.

    In tranditional side mount, do you keep the tank you are NOT breathing on or off? If off, do you stow the 2nd stage? If off and stowed, the donor donates what he/she is breathing, then he/she has to go the the "off" tank, turn it on, deploy the stowed reg. If in a real emergency case, it seems to be more steps that I like.

    I agree with AG's setup is meant to fit into team diving. So this makes me thinks that if the tranditional side mount divers are more in the mind set of solo divers, self proficient and less team oriented?
     
  8. rongoodman

    rongoodman ScubaBoard Supporter ScubaBoard Supporter

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    Both tanks are always on, and in my case, if I'm breathing the necklaced reg(left tank) the other one is clipped off to a shoulder D-ring. If it's on a long hose, anticipating gas sharing, the bolt snap is attached by some type of break-away.
     
  9. DevonDiver

    DevonDiver N/A

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    It's normal to leave both regulators on, for most agencies. Turning regulators off is pretty specific to the UTD Z-manifold.

    When setting up sidemount with the intention to closely replicate (and thus more easily match protocols with...) back-mounted technical configurations; the left-side hose will be on a short hose, routed behind neck and stowed in bungee necklace. The long hose routed 'hog' up from the right-side and clipped off when not being breathed.

    The sidemount diver would typically donate the long-hose. If breathed at the time, the donation would be identical to back-mount. If not breathed at the time, they would disengage the bolt-snap (hence, breakaway connection) and donate.

    I teach my sidemount courses with a 40" left-side regulator hose (the same as I have for my deco tanks). I ensure the regulator is detachable from the necklace. That way, should a mixed-team back-mount diver get confused between 'from the mouth' or 'from the long hose' donation, they can take either and immediately access gas. Either way, I have an immediately accessible regulator to switch to.... and because I am well practiced at regulator swapping (a core sidemount skill, repeated every 20bar consumed on every dive), this poses no problems. I can swap the receiver onto my long-hose once they have recovered composure from air-depletion.

    This is, typically, the same protocol that most technical divers would follow if sharing air during deco.

    I've never encountered a problem air-sharing on sidemount and do dive in mixed teams. I am very team orientated and train my student to be so also. Sidemount students (non-UTD) grasp it pretty quickly. Backmount divers grasp it pretty quickly (when learning deco/tox procedures) too...

    Sidemount air-donation is simply: Donate the long-hose.
    Backmount air-donation is simply: Donate the hose being breathed (the long hose).
    Decompression donation is simply: Donate the hose being breathed (not the long hose).
    Ox-Tox symptom donation is simply: Donate the long-hose (in most cases).

    That small distinction between long-hose donation breathed/stowed (a 4" variance in location) shouldn't cause undue complication (to any competent diver). If it does, then intelligent configuration of the short hose covers the contingency of confusion.

    If someone comes to me and signals OOA, they'll get my long-hose and receive gas.
    If someone comes to me and snatches the reg in my mouth, they'll get whichever hose.... and receive gas.
     
  10. mathauck0814

    mathauck0814 Assistant Instructor

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    Team diving isn't the "problem" being solved, most agencies discuss team diving techniques - and frankly for an open circuit team the GUE standard has solved the team diving question; but rather mixed team diving. I've spent countless hours with our local UTD instructors (including Andrew himself) attempting to understand this and it is horribly misguided. Once you realize that mixed teams are a bad idea, this system doesn't have a real application.
     
    xdjio and PfcAJ like this.

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