Wesley Skiles' widow suing over rebreather

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Not that I understand rebreathers, but what would be the significance of the air diluent bottle being drained? Is that potentially relevant if it occured during the dive?
 
Got a bit distracted by all this flush / do not flush talk and may have missed some posts but have you seen this report on Deep Life?

www.deeplife.co.uk/or_files/RB_Fatal_Accident_Database_100725.xls

It has a list of RB accidents from 9th April 1949 to 4th September 2012.

The entry about Wes says:

This statement:
The data on the sensors shows only a marginal failure: only just under the 8.5mV limit. However, this error is not sufficient to cause hypoxia.
is utter nonsense. Anyone with any real rebreather experience will know why.

---------- Post Merged at 11:44 AM ---------- Previous Post was at 11:42 AM ----------

Not that I understand rebreathers, but what would be the significance of the air diluent bottle being drained? Is that potentially relevant if it occured during the dive?

It could be a number of reasons which may or may not be connected to the accident.
 
Not that I understand rebreathers, but what would be the significance of the air diluent bottle being drained? Is that potentially relevant if it occured during the dive?

The "air dil" is something that could be breathed that would sustain life. My understanding is the way Wes's rig was set up was there was no way for him to get to it.
 
several absolutely wrong statements...

The comment about voting logic is to support their design that doesnt use voting logic...

the comment about the HH resetting the po2 to 0.4 is incorrect.. if the controller resets for any reason po2 is set to 07. ata

regardless of manufacturer's minimum voltages... the initial test shows the sensors were reasonable in final measurement (no information on responsivness of sensor). Before the sensors were sealed in a vacuum bag by the coroners office (not something the manufacturer would do), they had ok readings at points tested.

The location of the ADV on the Optima allows the diver to easily pull Dil from the cylinder (priority over loop), the inspired gas wount be what the sensors are showing at the time... Its not a design flaw, just a choice....

the "LOC" could also be hyperoxia as well.
 
I keep going back to hyperoxia. More than likely the sensor with the highest Mv rating would have eventually been voted out. Perhaps what's happening is the two laziest sensors are under-reporting the actual loop PO2. The O2 solenoid fires, and eventually the actual PO2 climbs while being under reported by the handsets (except on the good sensor which would have been voted out anyway). Uh oh...

Now a Dil flush would have been important to validate the sensors, perhaps he doesn't have any/much left. Maybe he does figure it out and began using SCR mode. That could explain the absence of Dil. He needed a large source of Dil, or an OC bailout but apparently he left those options at the dive shop. He'd have little choice but to breathe off the ADV for as long as he has gas with the loop PO2 being essentially unknown. At a certain point, the only choice was to risk the ox-tox or take the drowning. He runs out of Dil and takes a huge slug of O2 via the manual add button.

Bad things follow...
 
I keep going back to hyperoxia. More than likely the sensor with the highest Mv rating would have eventually been voted out. Perhaps what's happening is the two laziest sensors are under-reporting the actual loop PO2. The O2 solenoid fires, and eventually the actual PO2 climbs while being under reported by the handsets (except on the good sensor which would have been voted out anyway). Uh oh...

Now a Dil flush would have been important to validate the sensors, perhaps he doesn't have any/much left. Maybe he does figure it out and began using SCR mode. That could explain the absence of Dil. He needed a large source of Dil, or an OC bailout but apparently he left those options at the dive shop. He'd have little choice but to breathe off the ADV for as long as he has gas with the loop PO2 being essentially unknown. At a certain point, the only choice was to risk the ox-tox or take the drowning. He runs out of Dil and takes a huge slug of O2 via the manual add button.

Bad things follow...


We can't assume the dil was run out during the dive.. if the MP is out and above the body the ADV will continually freeflow (unless it is severely detuned or the ADV is disabled - which it wasnt) quickly depleting the gas..


unfortunately there can't be a 100% certaintly of the health of the cells.. The coroner's office vacuum sealed the cells causing cell #1 to leak electrolyte.. on the original inspection of the rig when exposed to air, cell #1 read 0.21, cell 2 was voted out and cell 3 read 0.18.. when the cells were checked with a cell checker cell #1 was low in air and across the board.. in fact the values presented would not have allowed the cell to calibrate so, it can not be a representation of that cells status during or immediately after the dive.. cell #2 (which was voted out on the surface ( a .03 variation would easily do it) ) reached the expected numbers for the working setpoint (1.4), cell #3 during the cell test what should have been a 1.4 would only have measured 1.3.. these 2 are close enough where they would be considered to be agreeing and would be part of the average.. (with these 2 cells only the avg would be 1.36 lose enough where the solenoid wouldn't be continually firing).. on the surface with the initial test the diva was vibrating as would be expected with the way the cells tested in air..

For the relatively short exposure, the po2 he was diving (even with it averaging a little low) normallly shouldn't cause a cns issue... even so hyperoxia IMHO is a much more likely scenario than hypoxia..

I am wondering if the prescription drugs found in Wes's blood and urine tox screeens would have altered his suseptibility.. 3 pain killers (opiates and narcotics) as well as a common prescription sleep aid were found in his system.. I was reading side effects of all the drugs and at least one is known to enhance the effect of drugs that produce drowsyness...
 
We can't assume the dil was run out during the dive.. if the MP is out and above the body the ADV will continually freeflow (unless it is severely detuned or the ADV is disabled - which it wasnt) quickly depleting the gas...

You make an interesting and valid point. I hadn't thought about the ADV firing after LOC because I never (and I mean never) leave my in-line shutoff in the "on position " on my ADV because IMHO the ADV is too aggressive/sensitive. BTW - I made the "it's too sensitive" comment on RBW and several people told me exactly how to solve that "problem" with a simple twist. I don't like to get too creative, so I just left it alone.
 
Only been diving the OptimaFx since Jan, and have about 50 hours on it over the summer shooting video on ocean dives. Two guys I dive with also have been diving OptimaFx CCRs for a few years already. We've all conjectured between ourselves on what could have happened to Wes. One thing we all agreed on was if you were not trained on using the OptimaFx specifically, it would be reasonable to make an uninformed mistake of going hyperoxic by surfacing and then making another hasty decent if you don't remember to drop your PO2 setpoint before you head back down. It seems not being trained on the OptimaFx coupled with the task loading of toting a very large camera system solo down from the surface would elevate one's risk. I don't even need to mention the risk of not having OC bailout.
 
Has anyone heard any news about the proceedings?

D

Sent from my GT-I9300 using Tapatalk 2
 
https://www.shearwater.com/products/perdix-ai/

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