OUT OF AIR - Last ditch effort breath from you BCD

[redacted]

I heard somewhere that if you are out of air with no air anywhere, you could breath the air in your bcd while kicking hard to the surface. Is this common practice

Works only if you eat enough spinach.

 

[Mandy3206]

The only possible scenario that I can think of to do this is if you're diving solo, got entangled, drop your cutting devices and ran out of air (even your redundant source), then you may take the last breath before you die entangled in the depths and never be found.

I seriously doubt this guy is a divemaster, since some it's posts don't make sense at all and a divemaster should know better.

Then he got offended when the right answer is given to the stupid question asked.

 

[PaulVS]

This brings up a question I've been meaning to ask, but didn't want to sound stupid.

The last time I took a scuba course back in the 70's I distinctly remember being told that due to air expansion - at almost any recreational diving depth you could do what is now called an controlled emergency swimming ascent, slowly exhaling all the way to the surface... and you would not run out of air. Now in my PADI course I'm told that only works at less than 30'.

Assuming you you haven't exceeded NDL... is this true or not? Has anyone here tried to surface from greater than 2 ata without inhaling?

 

[JMdiver]

I've done it from 60ft and didn't have a problem.

Happy Diving
John

 

[O2BBubbleFree]

This brings up a question I've been meaning to ask, but didn't want to sound stupid.

The last time I took a scuba course back in the 70's I distinctly remember being told that due to air expansion - at almost any recreational diving depth you could do what is now called an controlled emergency swimming ascent, slowly exhaling all the way to the surface... and you would not run out of air. Now in my PADI course I'm told that only works at less than 30'.

Assuming you you haven't exceeded NDL... is this true or not? Has anyone here tried to surface from greater than 2 ata without inhaling?

I haven't, but I started a thread on your question, maybe two years ago?

My OW instructor told me that he 'know a guy' who had done one from "more than 90' down."

Also, some guys posted on my thread that there was some guy (how's that for ambiguous?) that was testing his theories on bailing out of a submarine, and basically did a CESA from some unbelievable depth, like 400'.

Maybe someone who knows more details can fill in.

Later that same day: Here's the thread I mentioned. Post #25 gives specifics of the (almost) 400' CESA.

 

[dherbman]

Now in my PADI course I'm told that only works at less than 30'.

After 30', it get more difficult to maintain the proper volume in your lungs. The deeper you go, the easier it becomes to exhale air beyond the rate at which it is expanding. The air will not expand as fast and at 30FPM ascent rate, it would be even harder, but in no way is it impossible.

 

[Damselfish]

Jeez, lighten up on the guy, lots of the posts sound like attacks. Yes it's a really stupid situation to run into and there are lots of better alternatives, but an interesting enough thing to discuss. I think doing this was mentioned in my OW as a last ditch thing. What I usually hear people say is you don't want to do it because of the nasties possibly living in the BC, and then typically someone else points out that the nasties are better than drowning.

 

[DiveGolfSki]

I heard somewhere that if you are out of air with no air anywhere, you could breath the air in your bcd while kicking hard to the surface. Is this common practice

I nice theoretical discussion. Harder to use in practice. The best solution is (1) avoid it in the first place and (2) practice emergency ascent until you get proficient with it.

Besides, I can't use the air in my bcd ... where do you think I store my cigar smoke?

 

[tjmills]

I would consider this one of the things that you keep in the back of your tiny little brain (referencing mine of course) if you were ever in a situation where you had to do a free ascent from deep. This would be a last minute decision after analyzing your situation.

Could you breath into your BCD on the way up? Sure? would it actually help or slow you down fumbling with the thing? Seems like one of those things where you have to make a last minute decision depending on your situation and depth.

Could you practice it at shallower depths? Sure but you won't get the same expansion rates and you are likely to drown trying.

Even if you don't breath into your BC, you are likely to have a little bit in there if you absolutely can't hold your breath any longer. Again, another last minute decision kind of thing. As you ascend, that air will also expand slightly and may give you half a breath but again...would that help you or just slow you down and expend more energy which requires more air?

I would almost be willing to bet that staying calm, focusing on only the task of ascending to the surface without panicing is likely to result in a higher chance of making it. Best choice is to simply not run OOA but in the case of a EXTREME equipment failure and no buddy you have to make this decision on your own. Chances are...your buddy is probably closer than the surface but if not....using energy to do something that is not propelling you to the surface is probably not going to help much.
With that said, if I didn't have a choice and was nearing the blackout point...would I suck on the BC to see....yep.

 

[HowardE]

Besides, I can't use the air in my bcd ... where do you think I store my cigar smoke?

Now this sounds like a topic for further discussion.