One dead, one missing (since found), 300 foot dive - Lake Michigan

[broncobowsher]

What are you aiming for?

Sounds like someone is despite to point fingers.

 

[Cert1967]

What are you aiming for?

Hello Marie,

Aiming for? What would I be aiming for? You are implying something, what is it?

@Renee3420 asked a simple question and I pointed him to resources that might assuage his curiosity. Each point of contact listed will release all available publicly discoverable information in accordance with their administrative procedures and applicable law. Some of the information is available from official government web sites for free. Other sources may require a FOIA request and a small fee.

FOIA benefits are well established as in the public benefit. Wisconsin FOIA was codified - from memory - in the mid-80s.

I am simply pointing out that ownership structures are often more complex than they appear on the surface - and for good reason.

DAC may have full ownership of the Alma, but then again, they may not.

If you are interested in the history of Wisconsin Public Records - a good starting point would be the below referenced Marquette Law Review article.

https://scholarship.law.marquette.e...ferer=&httpsredir=1&article=1913&context=mulr​

This topic is in the 'Accidents and Incidents' section of SB. Ownership and financial considerations are often important factors to review in accident analysis.

 

[Brad_Horn]

However in the context of this scenario/incident (rebreather accident at 300ft), iI think it's clear that WOB and gas density at that depth (J/m) could have an impact

Sure

From my point of view a CCR has a higher WOB than OC, because your lungs act basically as a pump. You are using your lungs to move gas through the exhalation loop, exhalation counter lung, scrubber and back through the head, inhalation counter lung and inhalation loop. This in it self causes a higher WOB than OC. Next you have the position of the counter lungs which can adversely affect your ventilation effort. (static lung load).

Not quite.

Based on the rEvo rebreather user manual http://www.revo-rebreathers.com/wp-content/uploads/2016/02/Manual_rEvo_III_CE_2014_v05_ENG.pdf "Work of breathing: at 100m depth, 4° Celsius, 75 RMV (3liter tidal volume), using 2.7kg Sofnolime 797, using any trimix or heliox (PPN2 <= 4.0 bars) <2.45 J/liter in horizontal position and <2.75 in vertical position."

So when scooting the WOB of the unit would have been in the order of 2.45J/L, increasing suddenly to 2.75J/L if the divers went vertical to ascend and swim up the line. Assuming issue with scooter/set. 2.75J/L being the maximum allowed WOB for CE. The exact WOB of the sets for this dive being an unknown variable based on the specific gas density of the divers diluent gas as plumbed in.....
This is assuming that the default DSV wasn't swapped out for a BOV. As certain ones like those by GolemGear/IQsub would as I understand it have significantly increased the sets WOB.

There are rebreathers available that offer near half this WOB, near comparable with the best OC regs. And there are rebreathers available with twice this WOB. Assuming the same trimix/heliox as used on this dive.

Of course that all might be irrelevant noting the 75min scrubber duration the rEvo user manual notes as a limit for 100m 4'C dives.

 

[cerich]

This topic is in the 'Accidents and Incidents' section of SB. Ownership and financial considerations are often important factors to review in accident analysis.

is there anything that leads one to believe it's relevant to this accident? Because from what I have heard from various sources is not in any way pointing that way,and the actions of the captain more than professional and commendable

 

[Marie13]

is there anything that leads one to believe it's relevant to this accident? Because from what I have heard from various sources is not in any way pointing that way,and the actions of the captain more than professional and commendable

I've heard the same. This is my local charter op. For those of you who don't know, Double Action is owned by the same folks who own DRIS. If that doesn't tell you anything, I don't know what does. You know how Mike operates the dive shop/online shop. Why would the charter op be any different?

I guess some people just want to point fingers. Whatever happened, it happened deep below the surface. The boat didn't leave divers in the water, drifting for hours, or run them over. The Alma's captain is very safety conscious. I've dove off the Alma several times.

 

[rjack321]

A police report is not an accident report. Although I'm sure the publication of a couple of witness statements taken out of context would add another 23 pages of speculation and second guessing to this thread.

 

[ChuckP]

I wish there was some international association that reviewed all scuba fatalities or even major accidents and accumulated the data into some public report so that whatever could be learned from the incident was out there.

Out of due respect for the family, loved ones and those affected by this - I hate to see the speculation.

I do love reading about the re breather aspects and particulars but I think it belongs in the re breather thread, not here.

 

[altaskier]

I wish there was some international association that reviewed all scuba fatalities or even major accidents and accumulated the data into some public report so that whatever could be learned from the incident was out there.

Doesn't DAN do this to a certain extent?

 

[rjack321]

Doesn't DAN do this to a certain extent?

DAN co-authors review other people's reports and the editor compiles them into pithy lessons learned.

They dont do any investigations (interviews of witnesses, examination of gear, autopsies, toxicology, testing breathing gases etc) of their own.

 

[michael-fisch]

There is a guy in France diving regularly in the 200M range using a double "home-made" rb with axial scrubber.

Then I stand corrected, although I cannot understand why anyone doing that sort of diving would use a suboptimal scrubber design and survive. Trying to suck gas at 21Bar through 8" of 797 Sorb is extremely hard work. Even if you use the CD Grade coarse sorb the WOB is still very high.

Michael