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Accident on Southern Cal Oil Rigs Dive

Discussion in 'Accidents and Incidents' started by Hatul, Nov 11, 2017.

  1. KevinNM

    KevinNM DIR Practitioner

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    I went diving on my pony once. I had no problems, but realized that this could have been very bad. It's easy to do if they are similar second stages and both back mounted.
     
  2. CuzzA

    CuzzA Solo Diver

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    That is a very unfortunate update. One we've heard before. I agree with everything Mr. Powers stated with the exception of unequivocally not diving at 1.6 ppo2. Nevertheless, visually differentiating your primary reg from your pony is absolutely critical. Attached is a picture of the yellow mouth piece on my pony reg. Not to mention I necklace that reg. There is simply no way I could mistake the two regulators. My pony bottles also have vindicator knobs.

    Cheap risk mitigation. $3.50... Standard Neon Yellow Long Bite Regulator Silicone Mouthpiece

    20180403_203715.jpg
     
    Last edited: Apr 3, 2018
    dberry, kelvkwok and infieldg like this.
  3. Marie13

    Marie13 Great White

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    Location: Great Lakes
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    Since I took old pony reg to be part of SM regs, I put my old yellow octo second stage onto pony. Just using what I had, but it really makes sense after reading the accident update.
     
    CuzzA likes this.
  4. johndiver999

    johndiver999 Barracuda

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    I find it unlikely that using 32% for 9 minutes at 130 ft is going to cause someone to pass out. Possible, but unlikely.

    Was the pony bottle worn as a stage bottle or mounted on the main tank? The position of the tank would seem to be relevant in the chance of getting the regulators mixed up.

    What is the basis for demanding that a pony contain air not nitrox? I can see where it would make things safer if diving in depths that could possibly exceed the nitrox depth limits, but that is not common to all dive sites. What's so bad about a pony with nitrox that it should never be used?
     
  5. CuzzA

    CuzzA Solo Diver

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    Ask yourself this. What benefit is there to putting nitrox in a pony bottle?
     
  6. boulderjohn

    boulderjohn Technical Instructor Staff Member

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    I would say very highly unlikely--to the point that I would very nearly discount it.
    The general thinking on a pony is that if it is to be an emergency resource, it should be breathable at the deepest depth to which it might be needed. There is no reason that it could not be a suitable blend of nitrox, but some people choose to have a different philosophy.
     
    shoredivr likes this.
  7. boulderjohn

    boulderjohn Technical Instructor Staff Member

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    I am not going to speak for pny bottle users in general--I don't use one myself--but there would be a minor benefit with a nitrox blend in the case of a diver going out of air and needing the pony. If a diver were to get into such a fix, that diver would likely be at or beyond NDLs, in which case the lower nitrogen percentage would have a benefit upon ascent.
     
  8. CuzzA

    CuzzA Solo Diver

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    I suppose, but if you're matching your MOD with the dive how much nitrogen are you really cleaning up? For example a planned dive to 130 ft. at 1.4 ppo2 is what, 28%. Is that extra 7% going to make that much of a difference for the ascent and safety stop? Not trying to be argumentative. Honest question.

    Edit to add: Personally, I'd rather not have to think about what is in the pony. I also don't want to be constantly dumping and adding gas for different dives. Fill it with air and forget about it.
     
  9. johndiver999

    johndiver999 Barracuda

    # of Dives: 500 - 999
    Location: Gainesville FL
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    Those are reasonable reasons for using air, but they don't seem so serious or essential that they constitute a justification for someone saying "NEVER use anything but air".

    "Don't jump in the water with a tank filled with something you can't use in an any emergency" makes sense (if you are not a technical diver), but the admonishment to NEVER put anything but air in a pony seems to providing a simplistic rule that is not applicable everywhere - and probably entirely irrelevant to the accident which occurred. So that is why I raised the issue.

    What if your (air) pony leaks down between dives? Is it better to top it off with an equalizer hose with a little nitrox or add no more gas if no compressed air is available on site - might be an example where using nitrox could make sense.
     
    CuzzA likes this.
  10. raftingtigger

    raftingtigger Divemaster

    # of Dives: 500 - 999
    Location: Woodland, CA, USA
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    Johndiver999. You are thinking, and taking into consideration the dive and circumstances. I agree with your thinking. That said, in my case I don't want to have to think about what is in my pony (except test for CO), and want it usable at any depth. Mine always contain air as a result. Of course I reserve the right to change that for a specific dive.
     

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