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Fiona Sharp death in Bonaire

Discussion in 'Accidents and Incidents' started by JohnnyC, Oct 18, 2019.

  1. skippy311

    skippy311 Angel Fish

    # of Dives: 25 - 49
    Location: Korea
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    Ar dheis Dé go raibh a hanam

     
  2. Kinasi

    Kinasi Angel Fish

    # of Dives: 1,000 - 2,499
    Location: Germany
    6
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    What does that mean?
     
    skippy311 likes this.
  3. wedivebc

    wedivebc CCR Instructor ScubaBoard Supporter

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    It's Irish. Google it.
     
    skippy311 and ChuckP like this.
  4. Dan

    Dan Orca

    # of Dives: 500 - 999
    Location: Lake Jackson, Texas
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    On the right hand of God was his soul
     
    skippy311 likes this.
  5. DiverLaura

    DiverLaura Dive Equipment Manufacturer

    # of Dives: I'm a Fish!
    Location: From the edge of the deep green sea
    847
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    Last dive of trip after a number of tech range dives, correct?

    Any chance she was doing a washout dive (high PPO2 deco at the deep stops) and combined with the PPO2 spike at depth, Hyperoxia simply bit her in the ass? (I've read through the entire thread and didn't see it mentioned).

    For folks wondering what I'm talking bout, there was a practice in my generation of tech divers (early to late 90's) to run -very- hot deco especially after a series of dives when flying home was in the cards OR you felt a little subclinical niggle. Perhaps a deep dive to crush the bubbles and then hot deco at the 70-80' stop to 'wash' them essentially self treating. PURE speculation just tossing it out there, but it wouldn't be the first time the practice killed a very very experienced diver.
     
  6. dmaziuk

    dmaziuk Regular of the Pub

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    Hmm. 70-80' would be about at the bottom of the wall near Buddy's.
     
  7. Peter69_56

    Peter69_56 Divemaster

    # of Dives: 500 - 999
    Location: Australia
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    A question for you, have you ever had a CO2 hit? Are you speaking from experience or from what you know?

    I am not trying to be smart ro have a go at you, but I ask for the following reason.

    I have never had a CO2 hit but have had a caustic hit. I have however had a friend who had a CO2 hit from a canister that had come loose in his breather. His description to me was the following. "I felt something was wrong, just didnt feel right. I cleared the loop with DIL. This seemed to sort me so I continued on. A little while later I knew something was wrong and signaled to my buddy (his instructor) that I was aborting. At that stage I couldnt think properly and developed a huge migraine. I had only to swim maybe 15m to the shot line. I couldnt even get my head right to bail. It was only that my buddy was there who helped me switch, and helped me through the deco stops. I had such a blinding headache I could not function at all and just wanted to roll up into a ball". It wasnt until I got back on the boat, and was on O2 for some time before I regained some sort of functionality".

    Now they are his words and his experience, so to say someone could not have died from a CO2 hit think is wrong. I can see from his experience where someone could easily stop functioning and just give up. Specially if a solo rebreather.

    I agree the BOV gives you a chance to swap over, but it doesnt mean you have the ability or capacity to with a CO2 hit. From the description above, I would suggest my friend would not have been able to change over. With my caustic hit, I could have but would not have wanted to breath from a contaminated BOV, hence why I have a BOV but also a reg on each bailout tank as well as an LP line.

    Thats my thoughts anyway.
     
    InTheDrink and rjack321 like this.
  8. Peter69_56

    Peter69_56 Divemaster

    # of Dives: 500 - 999
    Location: Australia
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    And there is the rub. You are dumping from the loop because as you ascend, the loop volume grows, but at the same time the PPO2 drops so you have to add oxygen. So you are adding gas and dumping gas at similar times. If your unit is badly designed and the oxygen add outlet is near the dump or relief valve you can be adding oxygen and dumping it at the same time if you dont do it right.
     
  9. Peter69_56

    Peter69_56 Divemaster

    # of Dives: 500 - 999
    Location: Australia
    1,536
    628
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    So true "There but for the grace of GOD go I"
     
    BenjaminF likes this.
  10. RainPilot

    RainPilot OC/CCR Instructor Trainer Staff Member

    # of Dives: I just don't log dives
    Location: UAE
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    GENERALLY speaking, the dil will be added on the inhale side and O2 on the exhale. This is to allow the O2 to mix on its way through the machine, avoiding localised spikes (If you, for example, breathed very rapidly and O2 was being added just before the mouth, you could be breathing next to pure O2 as the machine tried to raise the set point)

    This design is to avoid the issue you mention, as well as to allow you to immediately get the "good gas" if you need to do a dil flush in case of a hot loop composition. Thats not to say all units are like that, but it is a pretty constant design paradigm in the industry.
     
    BlueTrin, fsardone and The Chairman like this.

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