Breathing from BC

[InTheDrink]

Doubler, I take your point. But if I might elaborate a bit...

I think there's an important distinction to make first off. I am not suggesting exhaling back into the BC. I am exhaling into the water. So there would be no CO2 build up, from rebreathing as such.

The logic I have about the procedure is simply that there is air in my BC. If I have no other means of getting air, then this is a means. Particularly in a CESA. As your air expands during your ascent, you could take a breath from your BC as you ascend. This could help you not exceed a safe ascent rate. Or in the event that you're too deep to make it to the surface on your existing breath, give you that valuable air.

I'm happy for you to shoot this down as I don't want to have something in my 'armoury' that's not viable - that, I can see, is dangerous. But at the same time, I don't see a failure in my logic. In terms of the effect of fear in a real situation - I agree, this is totally different to a controlled environment. However, surely this is the reason we practise? So that the panic can be mitigated by understanding available options and by having drilled it.

J

 

[Nemrod]

To breath from the BC you do not exhale back into the bladder. You hit the inflator, take a breath, exhale through your mouth or nose into the water--not into the bag. This is not a practical solution for anything. It was widely discussed during the 70s BEFORE people used octopus regulators. The BC, a horsecollar type, came into limited use about 1972. Most did not initially have power inflators but soon a power inflator was common. Immediately there was all sorts of discussion about using it to breath from. Obviously as soon as the octopus came into wide use in the 80s there was no reason to breath from a BC. A single tank rig now has a single first and two seconds. If your primary fails you have a octo second, if neither work then that means your first stage has failed in which case your power inflator will not work either.

Since I weight to have no air in my BC or only a puff or two there would be no air in my wing to breath typically if I were OOA. If you are weighted and at depth with exposure suits etc and were OOA then there will be some air in your BC, a breath or two might be available in a CESA, good luck with that.

N

 

[InTheDrink]

A single tank rig now has a single first and two seconds. If your primary fails you have a octo second, if neither work then that means your first stage has failed in which case your power inflator will not work either.

Power inflator? not relevant surely? I'm talking about pressing your BC purge. Dumping/venting gas. Nothing to do with first stage. Or second stages.

Or am I missing something?

 

[don Francisco]

J
In a real emergency, the last thing you want to do is waste time or mental effort with an unreliable technique. You want to be focused, decide your best option, and execute it seamlessly. You have enough time to effect a plan, but not enough to fool around.

In order to have any possible, however farfetched, need of the BC plan two things would have to happen. First you'd have to be out of sight or out of range of your buddy, and than while in that condition experience an out of air situation. Assuming you're disciplined enough not to breath your air down to zero while alone, we're talking about a rare catastrophic event during that narrow time span between when you found yourself alone and when you dealt with it.

I hate to say it, but if you managed your dives that poorly, how can you expect to manage your self-rescue?

Remenber the army way: KISS, keep it simple and straightforward (polite version).

 

[Nemrod]

Power inflator? not relevant surely? I'm talking about pressing your BC purge. Dumping/venting gas. Nothing to do with first stage. Or second stages.

Or am I missing something?

Yes, the last paragraph of my previous post.

We used to actually do this stuff, for example, the Fenzy even has it's own bottle and you can be sure people tried breathing from them, like I said, good luck with that.

N

 

[InTheDrink]

Well Nemrod, that's kind of a trite response given that you made a totally irrelevant statement about power inflators. nevermind.

DF, I agree, it would have to be a catastrophic incident. I haven't had one of those but I've had nearly one where current went from moderate to having to hold on to wall for dear life. Then my primary failed. This wasn't catastrophic cos I was near my buddy and guide. Altho I was upstream from them. Had I been down stream there is no conceivable way I could have got to them. I also had an octopus.

But it did make me think about contingency plans. I've never run OOA from poor gas management.

 

[Nemrod]

We used to practice breathing from the power inflator before the octopus was in common use, the earliest concept of the integrated octo/inflator.

You will find being OOA and with a couple of breaths of air in the BC challenging to utilize. What confused me was you guy talking about CO2 build up? If you inhale from the bag, exhale into the water there would be no CO2 build up. So, therefore posts previous to mine led me to believe that you were trying to breath from the inflator and exhale into the bag and then vent it. Otherwise how would you get a CO2 build up??

Since I have actually done ALL of these combinations in the water, at depth, I will stick with what I said, good luck with it, lol, adios.

N

 

[InTheDrink]

ok, lol too. Sorry if I got prickly

 

[InTheDrink]

Final point and I'll leave you in peace then

My initial thought with breathing from a BC was this was not something that you'd want to be trying to do when in a serious situation, task loading under a lot of pressure.

However, in the pool (yes, I know) I was surprised how easy this was - to the degree that it seemed a viable option in an emergency.

It does sound, however, from those out there that HAVE done it at depth and in adverse scenarios that it's not quite so easy under stress. So I'll draw the relevant conclusion that you'd hope there'd be better options. And like I said, not something I ever want to have to do in the wild. Sorry for letting this drag on and thanks for the input. I'm just trying to learn but I do need to challenge rather than just lapping it up irrespective - hope that makes sense.

Thanks,
J

 

[boulderjohn]

The logic I have about the procedure is simply that there is air in my BC. If I have no other means of getting air, then this is a means. Particularly in a CESA. As your air expands during your ascent, you could take a breath from your BC as you ascend.
J

But you do have another means of getting air as you ascend--your tank.

Your tank is not out of air. It is just so low on air that your regulator cannot supply it at the pressure you need. Air mut come to you at approximately the same pressure around you. As you ascend and the pressure decreases, your regular will be able to give you some air.

You are taught to keep your regulator in your mouth during a CESA. This is one good reason for it.