Rebreather problem in documentary

[Mr.X]

Well it's a pity you seem to have a negative inclination toward RBs now. It was the case early on that the pool of knowledge regarding the safe operation of RBs was limited. There was a spate of accidents due to what were at the time "received wisdoms" of how things were done.

Now that it has matured somewhat and many of the fault modalities have been identified and corrected/mitigated it is less of a "crap shoot".

It is still inherently riskier than OC but IMO some rewards are worth increased risk.

Better PO2 monitoring in the form of more reliable O2 sensors will be a welcome thing!

Oh and as to your query over why they don't have the same RBs in the video. My take is that it's not necessary, they were diving autonomously so little is to be gained by having the same gear. Sure you can share spare parts if you have a gear failure whilst topside but if you didn't buy gear with a particular buddy in mind then it's awfully expensive re-buying simply to take advantage of that.

Love the condescension. SB is not RB world, or whatever it's called these days. I have a pool of experience and knowledge with RB's and technical diving since it's early incept. With that I've seen enough in the way of accidents and macho bravado to seriously doubt the benefit of human exploration into areas where it can be done better with a ROV, or not at all. It's not very pretty when you see guys you know and love come up dead, or go missing. And with a high degree of regularity. The final straw for me was when Wes Skiles died. This was shortly after I had conducted some fairly dicey, ugly penetrations in a remote area where help was not accessible for days - or if at all. On concluding these penetrations I seriously debated the idea of worth & purpose. Explorers will always argue for 'human eyes' seeing things for the first time, but IMO - it's all about ego and not really about purpose. I know many will not find my particular viewpoint favorable, but at the end of the day I am still alive among my cohort of early adopters. I consider myself only lucky even with better technology.

Your take on solo RB cave penetration - is this first hand knowledge? Funny, that parts of the penetration dives were videotaped meaning someone was holding a camera. What was the cameraman using? A KISS? So do me favor - don't talk too high from your pulpit until you see enough in the way of serious mishaps and malfunctions to make you wonder why and what for.

X

 

[Plumb bob]

Mr X, You assume an enormous amount when you complain of condescension in my post. There was no such tone when I wrote it.

Your take on solo RB cave penetration - is this first hand knowledge? Funny, that parts of the penetration dives were videotaped meaning someone was holding a camera.

Well for a start no I do not solo cave dive. I did watch all of the documentary before commenting on it. Secondly autonomous does not necessarily mean solo, it just means that they were independent of one another, certainly the fact that they were starting quite a few minutes apart indicated solo but they may have been diving much closer together later on. As to the videotaping, the main videographer was Marcus Taylor with the help of Pete Mullholland and Edoardo Pavia. No mystery there..

What was the cameraman using? A KISS?

Not sure what the videographer was using, probably OC.

So do me favor - don't talk too high from your pulpit until you see enough in the way of serious mishaps and malfunctions to make you wonder why and what for.

There is no need to experience serious mishaps and malfunctions in order to offer commentary on diving RBs. By analogy there is no need to experience motor vehicle accidents to offer advice on avoiding them.

 

[Thalassamania]

I dove my first rebreather back in the mid 1960s, a Pirelli oxygen unit and have had cause, on and off, to use ever increasingly complex RBs since. I have to share Mr.X's jaundiced eye.

A rebreather is basically a Rube Goldberg machine that, if all is put together right and all is serviced right and all is used right will keep you alive in remarkable situations and let you do remarkable things. But, and there is a huge but, if you can't dedicate damn near full time to being a a rebreather technician and pilot or can not hire one of the few full time rebreather techs that are out there for your project, then you're kidding yourself and it is not a matter of if the RB is going to kill you, it is a matter (IMHO) of when. In my view the most dangerous thing that you can do in diving is to be an experienced, infrequent, RB user with any other interests. Wes was, tragically, a prime example of that, a very experienced, far from full time RB user, with many delightful, outside interests. If you find that a poor perspective to present to someone wanting to find out about RBs, sorry ... that's just the truth, as I have experienced it.

 

[Plumb bob]

I dove my first rebreather back in the mid 1960s, a Pirelli oxygen unit and have had cause, on and off, to use ever increasingly complex RBs since. I have to share Mr.X's jaundiced eye.

A rebreather is basically a Rube Goldberg machine that, if all is put together right and all is serviced right and all is used right will keep you alive in remarkable situations and let you do remarkable things. But, and there is a huge but, if you can't dedicate damn near full time to being a a rebreather technician and pilot or can not hire one of the few full time rebreather techs that are out there for your project, then you're kidding yourself and it is not a matter of if the RB is going to kill you, it is a matter (IMHO) of when. In my view the most dangerous thing that you can do in diving is to be an experienced, infrequent, RB user with any other interests. Wes was, tragically, a prime example of that, a very experienced, far from full time RB user, with many delightful, outside interests. If you find that a poor perspective to present to someone wanting to find out about RBs, sorry ... that's just the truth, as I have experienced it.

I agree with a fair amount of what you say T. But I can't see the complexity argument as holding true across the full range of units. Yes there are some very intricate units out there but there are units at the opposite end of the continuum that are no more complex than a couple of regulators and a "vacuum cleaner" without the motor..

I would never and have never claimed that RBs are for everyone (and by that I don't wish to make an elitist claim, I merely think that a little fanaticism is IMO a prerequisite) as you say T, it is not a take it or leave it "flash in the pan" choice. I personally think mass encouragement of casual divers to be a potentially cynical marketing exercise. But maybe not.. Time will tell. Hindsight will be, as always, 20/20.

 

[Thalassamania]

I... there are units at the opposite end of the continuum that are no more complex than a couple of regulators and a "vacuum cleaner" without the motor.

I remember one of those units (an mSCCR) that left it's inventor prone and unconscious on the bottom in about 10 feet of water where he was, thankfully, rescued. Turned out, through a series of errors he was diving a hypoxic diluent that was mixed for use at depth. Even "vacuum cleaner" simple RBs are just waiting to do you in at most every turn.

 

[Plumb bob]

I remember one of those units (an mSCCR) that left it's inventor prone and unconscious on the bottom in about 10 feet of water where he was, thankfully, rescued. Turned out, through a series of errors he was diving a hypoxic diluent that was mixed for use at depth. Even "vacuum cleaner" simple RBs are just waiting to do you in at most every turn.

But that's an accident that is quite independent of whether you are diving an RB or on OC. There have been many hypoxic OC events as you are no doubt aware.

 

[Thalassamania]

I am aware of a few mixed gas hypoxia incidents. So in that sense there are some similar risks, that with a rebreather get raised by orders of magnitude while with O/C get simply added together. It makes the risk analysis very different in the end. I was one of the first people to recommend the use of mixed gas rebreathers in the science community, especially for rather deep dives in remote sites where it was not practical to bring in a barge full of helium. But those sorts of operations are very different from what goes on in the recreational world, especially as it pertains to professionalism and strict adherence to defined procedures and checklists. Rebreathers are not, in my view, suitable for use on a holiday lark by the general diving public.

 

[Plumb bob]

Rebreathers are not, in my view, suitable for use on a holiday lark by the general diving public.

Well depending on the definitions of those terms you may be right.

 

[Mr.X]

Mr X, You assume an enormous amount when you complain of condescension in my post. There was no such tone when I wrote it.

Well for a start no I do not solo cave dive. I did watch all of the documentary before commenting on it. Secondly autonomous does not necessarily mean solo, it just means that they were independent of one another, certainly the fact that they were starting quite a few minutes apart indicated solo but they may have been diving much closer together later on. As to the videotaping, the main videographer was Marcus Taylor with the help of Pete Mullholland and Edoardo Pavia. No mystery there.. Not sure what the videographer was using, probably OC.
There is no need to experience serious mishaps and malfunctions in order to offer commentary on diving RBs. By analogy there is no need to experience motor vehicle accidents to offer advice on avoiding them.

Bob - your vocab. use needs work. 'Pity' is not a term I would use to emphasis a difference of perspective. That said, I reiterate - SB is not RB world and will leave it at that.


Personally, I could care less what the cameramen were using + the expedition details. To me it's 'yet' another deep hole in the ground expedition with skilled mates having a go. Having been this route multiple times the taxing routine of physically/mentally/financially getting ready for expedition-class dives + shooting documentaries has gotten old. These days broadcast channels aren't so hot to sell this genre of diving footage as it's become commonplace and to the viewing public - odd, inaccessible and obscure.


The thrust of my argument is akin to Thal's perspective. I have a less-than rosy feeling about RB's based on decades of use and the # of explorer pals now gone. I don't know how long you've been on RB's, or in the tech niche, but time, experience & age will change perspective. It's more than saddening when divers you've known and appreciated die using these things. Senseless when they are crazy tech dives for stupid china plates. Over two decades RB mortalities have become a repetitive event for me & hence the somber eye.


'Autonomous' use in a interesting term. We're all self supported on these things and as Thal mentioned I do find them R.Goldberg devices too. A 'autonomous' fatality occurred on a routine RB dive here in the NE US just last year. That diver had true Joie de vivre and we had many conversations about RB's prior to his move to the AP unit. He was very cautious, articulate and smart. Yet, he's gone.


The second point is about purpose - what are we really using these devices for? And why the need for epic dives? If one has a family, kids and such the pursuit of such goals is a truly selfish one. But that's another discussion about personality types driven to excel at these types of endeavours. At the end of the day - do it enough and it will come around to bite you hard.

 

[Plumb bob]

There are a series of paintings (bear with me, there is a point) that are called " Most Wanted" They were painted in response to polling in 11 countries on what people most wanted to see in a painting. Each is unique to the country polled. Now the themes that were common are revealing of our desires. These included: Open spaces, the presence of water, evidence of animal and bird life, a diversity of greenery including flowering and fruiting plants and an opening up in at least one direction to an unimpeded vantage on the horizon or a path winding out of sight. All those desired attributes indicate the circumstances we preferred during our evolution. We Humans are hardwired, it's in our genetic make up to explore. You are just as likely to stop divers pushing the boundaries as you are stopping the incoming tide.

Each diver has the right to accept or reject any level of risk they are not comfortable with, it is not up to us to proclaim the validity of their decisions. What purpose does it serve having a "Greek chorus" wailing "You're gonna die!" whenever RBs are mentioned?

If you do not find RBs or caving interesting any more then fine that's your choice.