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Unless @John Bantin is willing to share
Fiona Sharp death in Bonaire
- Thread starter JohnnyC
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mderrick
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Yep, a good example that changing just a single parameter, like descent rate, could change the whole picture.
I've done descents so fast that I wound up at depth with a PO2 that actually exceeded the calculated PO2 of the dil... depends on what setpoint was during the early part of the descent. Swimming along at 25 meters on 1.3 and then running down to 90 meters is different than jumping with 0.7 in the loop and hauling down to 90 meters. It's also possible to get to the bottom with hot dil and a reasonable PO2 if the loop PO2 is used to control the descent, assuming you don't have to flush with dil at that depth.
CuzzA
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I got similar info from an informant. Being that she made it to the 80ft. stop in a controlled manner should we assume her choice of gas was probably irrelevant as to cause of death?
We can't even assume that, with the limited information that we have.
What if she really did have a hot loop at 90m? Maybe she didn't seize at depth, but it's exposure and time. NOAA gives you 7 minutes at a PO2 of 1.65 for a single exposure, and prior exposure lowers the tox threshold later in the dive....
Very sad, following this one closely.
Wookie
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I wonder how long she spent at depth?
Dan
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Facts sent to me from an Insider:
Of course, if you have pertinent information you feel should be passed on, I am here for you. I will only pass on info at my discretion that I feel to be reliable.
This makes me wonder as she ascent to 80’, not far of the slope, she would be either in neutrally or slightly positive buoyant and she went unconscious at that bottom of the slope at that depth. Her jaw dropped, the regulator fell out of her mouth, her lung and the CCR filled up with water. She drowned, became negatively buoyant and sank to the bottom of the slope. Had she put on a gag strap, would it be possible for her to still be floating motionless in mid water and even slowly floating towards the surface, alerting the rescue class divers who happened to be in the vicinity to rescue her?
How many of you CCR divers are wearing gag strap during CCR diving?
CuzzA
Wetwork for Hire
Someone will correct me if I'm wrong, but I would dismiss the idea a gag strap would have changed the outcome. The purpose of the gag strap is largely for jaw fatigue during long deco and/or to buy time for a buddy to assist a diver that is toxing. You also have to remember that it takes a conscious human to control whether their airway is open or not. A gag strap would not do this for you and assuming you could get a perfect seal on the mouthpiece to keep water out while unconscious you would still likely embolize on the way up to the surface.
I think it's pretty safe to say that if you go unconscious while on a dive, 99% of the time you will not survive.
Exactly! Except for the last sentence.
If you read that French military rebreather study that I quoted upthread, they actually had a 94% survival rate with loss of consciousness, but that implied the presence of a gag strap AND a buddy.
Actually, this is one of the reasons why solo rebreather diving is an issue. I loved solo diving on open circuit, and I felt perfectly safe. But I almost never do that any more on CCR.
A gag strap is not a parachute that will save you no matter what. There are reasons why many very experienced rebreather divers don't use them, and reasons why few manufacturers include them as a standard. Unless someone is there to intervene, there is no reason why the hypoxia or hyperoxia that caused the LOC in the first place will spontaneously reverse itself and allow the diver to just wake up. And if you tox or become hypoxic, you aren't going to last that long even if you keep the loop in your mouth with an unbreathable atmosphere. It's not like you can just lie there for hours until your scrubber runs out, waiting for a rescue while unconscious.
So while they have their place (and I'm experimenting with one now), I don't think that people should assume that they take the place of other safety procedures.
Yes, but that's a different scenario than this one.
I'm not up on the latest from that tragedy, but in that case the gag strap might have prevented the loop from flooding on the surface, causing him to sink after he lost consciousness, presumably from DCS, right? So they might have been able to recover him and resuscitate him if he were floating and unconscious.
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