How those idiots (us) run out of air

[Tortuga68]

Dan seems to be talking about some scenario that never happened in this thread/OP

---------- Post added July 6th, 2013 at 12:53 AM ----------

Free water ascents: You need to know which way is 'Up'. Your bubbles go up...

Not always the case...

Slow your ascent as much as possible in the last 10'- I disagree with someone earlier who said they quickly ascend to check for boats. Motor boats are loud- if you hear one be prepared to get back down. When you're at the surface get positively buoyant so you're also able to be seen- if you're not, you're a speedbump

If you're referring to Dan's comments, that's not what he said. He said he would "listen... listen" then swim up quickly while twirling (looking) & staying negative so he could descend again quickly if required ( to avoid a boat).

Getting postive on the surface gives you limited options, there was a thread recently about a guy who lost both legs - in part I believe because he couldn't quickly descend again after surfacing

Dive computers also give a good indication of ascent speed

Not really, they usually lag and by the time they're beeping you can already be exceeding the recommended ascent rate. Look at a lot of rec. profiles downloaded from PDCs and you'll usually see a few ascent rate violations

 

[danvolker]

Possibly true. However, having taken a chamber ride myself for an "underserved" hit, if I were sharing air with someone with a reasonably full tank (say, 500 PSI) at 15 feet, especially with the additional control afforded by hanging on an ascent line, I would do the stop. In the very unlikely event that the SPG is over reading or something, you could CESA, but it would be pretty unlikely that would occur.

Of course, this would be a situation specific decision, and if there was panic, or lack of control of the injured diver, etc.. then I agree - surface without the delay of the safety stop.



This is of course different than blowing off a safety stop. I don't agree with you here, but again, obviously OOA with no on to share with is different from LOG and/or OOA with a buddy donating a second stage. In the scenario that the OP posted, they were sharing air on the ascent line and made it back OK (which leads me to believe that the DMs donating air had adequate gas reserves). In that scenario, a bolt for the surface, even from relatively shallow depths, does put a diver at risk for DCS and possibly pulmonary barotrauma if a panicked diver doesn't open his or her airway adequately. Sure, if the alternative is drowning, you do what you need to do to get to the big gas reserve on the surface. But the way the OP described the scenario, it doesn't sound like that was the case...

The two divers this thread is about, sound alot to me like what leads to one of the statistics--the one about OOA drownings..... I can see the two of these divers in the telling of the story, potentially having both run OOA, and easily sucked down any gas the DM had if they were in panic mode--which they probably would have been.

I am reacting to this thread as an OOA probability...not just as a low on gas- shame on me story...
I don't see these 2 as having practiced CESA's ...and with the trepidation over a "blue water ascent" I think the CESA would potentially be fatal for them.

If you have read my past posts--you know that my initial complaint would have been no gas management, a poor dive plan--all of these issues should have been impossible to be problems with the right planning.....

My reason for posting this stuff here---is that divers do need to have a sense of what to do in a Clus@@#F(** scenario, if they get themselves into one....this is what a CESA is for, and it is relevant to discuss how they would best survive the OOA for both of them which could be moments away if both are at 250 psi at 50 feet deep... I see this as problem solving they lacked....Of course they should never have gotten to this point in the first place.

 

[doctormike]

I am reacting to this thread as an OOA probability...not just as a low on gas- shame on me story...
I don't see these 2 as having practiced CESA's ...and with the trepidation over a "blue water ascent" I think the CESA would potentially be fatal for them.

If you have read my past posts--you know that my initial complaint would have been no gas management, a poor dive plan--all of these issues should have been impossible to be problems with the right planning.....

Right, you are making some good points, and I think that the issue of gas management, poor dive planning, and DM reliance has been pretty well covered in this thread.

I guess my point is that there are lots of variables to consider in any real world situation, and the good thing about debating them here is that less experienced divers can use this discussion to make decisions in the future.

I would caution against implying that one should definitely blow off a safety stop, or that one should never blow off a safety stop, or any dogmatic statement like that when there are scenarios in which you would do one or the other. Even re-reading the OP and his follow up posts, I'm still not sure exactly what the pressures and depths were towards the end of the dive, so that's why some room for decision making is a good thing, and that's what makes it a useful discussion (e.g. free ascent, SMB, direct ascent, try to find the ascent line, look for boats, look for shore, etc...etc..). You and I don't know how much gas the DM had (or each DM had, actually), and that's why there are different approaches based on the specifics, which is what I was saying in my last post...

 

[Tortuga68]

The definition of a safety stop is that it's not required. If you are OOG, you should definitely 'blow it off'

 

[doctormike]

The definition of a safety stop is that it's not required. If you are OOG, you should definitely 'blow it off'

Right, and most of the recent posts in this thread are about the difference between OOG and LOG and LOG/sharing gas and OOG/sharing gas, so the devil is in the details.



But I agree, if you are actually OOG, you should not attempt to evolve gills to do your safety stop..

 

[Adobo]

The two divers this thread is about, sound alot to me like what leads to one of the statistics--the one about OOA drownings..... I can see the two of these divers in the telling of the story, potentially having both run OOA, and easily sucked down any gas the DM had if they were in panic mode--which they probably would have been.

I am reacting to this thread as an OOA probability...not just as a low on gas- shame on me story...
I don't see these 2 as having practiced CESA's ...and with the trepidation over a "blue water ascent" I think the CESA would potentially be fatal for them.

If you have read my past posts--you know that my initial complaint would have been no gas management, a poor dive plan--all of these issues should have been impossible to be problems with the right planning.....

My reason for posting this stuff here---is that divers do need to have a sense of what to do in a Clus@@#F(** scenario, if they get themselves into one....this is what a CESA is for, and it is relevant to discuss how they would best survive the OOA for both of them which could be moments away if both are at 250 psi at 50 feet deep... I see this as problem solving they lacked....Of course they should never have gotten to this point in the first place.

The problem I have with CESAs is that it is not a magic bullet and is not a good solution for *all* the various ways one can find himself in a fuster cluck.

 

[flots am]

The problem I have with CESAs is that it is not a magic bullet and is not a good solution for *all* the various ways one can find himself in a fuster cluck.

Actually for an Open Water dive, a properly done CESA is a "magic bullet".

• You get access to all the air you want
• You don't drown
• You don't get bent

If you can't do a proper CESA because of the dive conditions, then it doesn't meet the definition of an "Open Water" dive.

If you can't do a proper CESA because of lack of training or practice, then that's a training issue.

Back when dinosaurs roamed the earth, most dives ended by "swimming up", and it worked just fine. Not quite as safe as a slow ascent and a 5 minute stop, but a lot safer than "bent" or "dead".

flots

 

[Adobo]

Actually for an Open Water dive, a properly done CESA is a "magic bullet".

• You get access to all the air you want
• You don't drown
• You don't get bent

If you can't do a proper CESA because of the dive conditions, then it doesn't meet the definition of an "Open Water" dive.

If you can't do a proper CESA because of lack of training or practice, then that's a training issue.

Back when dinosaurs roamed the earth, most dives ended by "swimming up", and it worked just fine. Not quite as safe as a slow ascent and a 5 minute stop, but a lot safer than "bent" or "dead".

flots

Really? How does being proficient at CESA help you if you are entangled? How does it help you if a tank fell out of your BC? How does it help you from picking a dive that is well beyond your abilities? How does it help you assess the best way to enter and exit a dive site? How does it help you if your dive computer fails?

As far as I can tell, all CESA does is give you a last ditch solution for one very specific problem that should be completely avoidable in the first place. And its not even the right first answer for that problem.

 

[captain]

Really? How does being proficient at CESA help you if you are entangled? How does it help you if a tank fell out of your BC? How does it help you from picking a dive that is well beyond your abilities? How does it help you assess the best way to enter and exit a dive site? How does it help you if your dive computer fails?

As far as I can tell, all CESA does is give you a last ditch solution for one very specific problem that should be completely avoidable in the first place. And its not even the right first answer for that problem.

Apples and oranges, CESA implies an out of air situation with unobstructed access to the surface. All problems are never completely avoidable, if they were no one would ever have any kind of accident. What does a failed computer or making an entry or exit have to do with needing to do an CESA. It is the right answer when all other answers turn out wrong.

 

[Adobo]

Apples and oranges, CESA implies an out of air situation with unobstructed access to the surface. All problems are never completely avoidable, if they were no one would ever have any kind of accident. What does a failed computer or making an entry or exit have to do with needing to do an CESA. It is the right answer when all other answers turn out wrong.

It might help if you read the context of the preceding replies.