Why no poor man's rebreather?

[Stoo]

I have an SPG on my OC gear. Running out of gas is still ALWAYS a concern. That's why I have an SPG and I monitor it.

Is it really though? You've been at this a while. Surely you check that your tank is full at the beginning of a dive and once in a while during the dive. I do, but not because I'm afraid of running out of gas, but to confirm that I've used about the amount that I should have. Admittedly, I wear doubles at home, but I generally do two dives on a fill

As for all the other stuff, you clearly know more about the technical aspects of RBs than I do, but as soon as I hear "injector" and "monitor" I assume that that stuff means $$.

It would be cool if you're right. Why don't you invent one? ;-)

 

[stuartv]

I think maybe you are too jaded on the subject of running out of gas on OC. In my opinion, it is ALWAYS a concern. It's not a MAJOR concern for people like yourself who are diving doubles AND have developed good habits. But, even you know that if do what looks a very benign swimthrough and something happens, it's a concern. You get entangled. It's longer than you thought and somehow a silt-out happens and viz is zero. You know that you cannot just park yourself and wait for help. You can't just park yourself and wait for the silt to settle. Why? Because running out of gas is a concern. Whether you run out sitting there, or whether you run out while trying to meet the mandatory deco that gets incurred during the time it takes to deal with the problem. It's a factor in every aspect of the dive.

I did not appreciate AT ALL the burden that weighed on the back of my mind on every OC dive (even on doubles) regarding the possibility of running out of gas until I was a few dives into diving on CCR. Then, I was swimming along the bottom next to the Spiegel Grove at 135'. My buddy and I passed two OC guys (with doubles and a slung bottle each) and I it hit me that they had pretty limited time to be where they were and I had (in a practical sense) all the time in the world. Sort of. Obviously, it's not infinite. But, the "extra" is SO huge compared to the planned use that it really feels like going from being in a small box to standing in a wide open meadow. It's like the comfort of diving doubles and have that huge amount of extra gas, but times 10. Or 100. And that different feeling - sort of a feeling of relief - was not something I expected at all out of my switch to CCR.

 

[Stoo]

people like yourself who are diving doubles AND have developed good habits.

LOL. If my buddies read this, I'm gonna catch a load of it! ;-)

It almost sounds like you want a piece of technology that will make up for poor diving habits. That would be cool...

 

[broncobowsher]

Just diving a rebreather is not a place for the poor to play. In any recreational types of diving going open circuit is the cheap way to dive. When people get cheap with a rebreather (running cells past there expire date, trying to get the last breath out of some scrubber) is when people die.

 

[njdiverjoe]

It almost sounds like you want a piece of technology that will make up for poor diving habits. That would be cool...

That is pretty much what I was thinking too when I read that post

 

[stuartv]

the development of Octopus seconds and actual BCDs made diving safer... and more expensive.

I think that kind of thing goes in cycles.

I'm just guessing that in the very early days, scuba tanks (in whatever form they existed back then) had a simple valve. Then, somebody decided having a reserve would be safer, so they invented the J valve. I'm sure that was more expensive than its predecessor. But, eventually, somebody invented a reliable SPG and the J valve was replaced with a more modern and, presumably, cheaper valve. Meanwhile, overall safety was still better than before. And overall cost was also cheaper, because you only needed one SPG, no matter how many tanks you had.

I think current CCR tech is somewhere around the J valve equivalent.

My imaginary device above was somewhat dependent on being an SCR. But, imagine if:

- O2 sensors were solid state and stone reliable
- scrubber cartridges, including the manufacturing process, were stone reliable
- CO2 sensors were solid state, and stone reliable, even in a wet and salty environment

Then, somebody put all that together in an electronics package that was as reliable as a Shearwater Perdix.

All of that seems not here yet, but within reach of the next few years.

For people who are only doing recreational dives, a CCR built on that might be comparable in simplicity to OC. Comparable - not necessarily the same. It might be comparable in reliability to OC. And it might be in the ballpark of the same cost as a full OC kit. And, for recreational divers, maybe even deemed not to require carrying a Bail Out. We're talking about NDL diving. Maybe this imaginary CCR includes an OC 2nd stage that is plumbed into the dil bottle and that is the only BO required. Thus, this 2nd stage can be donated to another diver or used by the bearer. Or maybe the CCR has a BOV for the user AND an OC 2nd stage for donation.

I don't know. It just seems like a lot of the discussion of "requirements" of CCR diving reflect assumptions that are based on the current state of the tech and are not necessarily inherent to the concept of diving a CCR.

 

[Diving Dubai]

MUCH larger commitment from the diver, in terms of time, money, and training, than does OC scuba.

I would agree. Although to refine that

As an experienced diver, the cost of the kit and the training is immaterial. Either you can afford (or can justify it) or you can't. If you really want one, you'll find the money somehow

For me It was the investment in time to clock up the hours needed to make the kind of dives I do now on OC (up to 50m - 1 hr run, two gases for Accel deco, in Blue water on a scooter in current). Roughly 2 years maybe less maybe more.

So I'd either have to skip my fav diving and concentrate in clocking up the hours, or FOMO (Fear of missing out) would click in, and I'd leave my CCR at home and jump back to the OC. Kinda pointless. That was the major stop for my decision

So that was my major rational against the decision (and I've never been shy about buying new shiney gear)

Now, If I'd have taken my OW on a CCR so that was all I'd ever known and then grown with it, that would be a different kettle of fish. We're a long way off that though - for the availability of economic rental units both at home and on vacation, that are simple enough for the average diver to jump into and dive, before they decide to purchase (if they do)

Will we ever get there? I don't know. For most people the gear is just an inconvenience allowing them to go underwater to see pretty stuff, so maybe CCR will remain in the small domain of the gearheads who need it for a specific task , or who want it because they can?

 

[stuartv]

LOL. If my buddies read this, I'm gonna catch a load of it! ;-)

It almost sounds like you want a piece of technology that will make up for poor diving habits. That would be cool...

Isn't that what an octo is?

Isn't that what a BCD is?

Isn't that what an SPG is?

According to my dad, who started diving at 14, in north Florida, including diving in the sinks and caves there, that's what all of those are. He dived for years with no octo, no BCD of any type, and no SPG. No BCD meant very precise weighting. No SPG meant that he was diving doubles and he would dive with one post turned off. When his reg got hard to breathe, he would turn that post on, let the tanks equalize, and turn it back off. And he would know that he was now at 1/2 tank. Rinse. Repeat.

He went into the Navy. He was a diver in the Navy, but he was not a Navy diver. However, his ship did assign him tasks in the water sometimes. He dived as deep as 200', on air, with double 72s, in a wetsuit, with no BCD and no SPG. Reliably.

You can ditch all that tech that is there to make up for poor diving habits if you want, but I'm keeping mine. My dad can call me a wuss all he wants!

 

[happy-diver]

I'm a poor diver.

It took more than fourty years of childhood fascination including the last ten years of reading and parts collecting

for this to become a dream come some how to fruition

Took a bit of lung fabrication to get such a beautiful neg test

in my laundry

and in here

To use after a bit of practice with ease on any dive I want


Menu Homebuilders

Complicated?
Apollo rebreathers

 

[stuartv]

Complicated?
Apollo rebreathers

Wow! That is cool. And a whole suit as a counterlung. LOL