AbyssalPlains
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Running out of air.
What really creates an OOA scenario?
- Thread starter psychocabbage
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OOA is caused by bad gas management or is the end result of equipment malfunction. It should never happen.
On the other hand, being without air can happen for a variety of reasons and can be the precursor to any number of bad scenarios if the diver is not prepared.
A second stage could depart from the mouthpiece, for example. Not a big deal to resolve, but it takes composure and the reality of being without air can be a strong contributing factor to panic.
A tank valve might be only partially on, delivering plenty of air on the surface, but starving the reg at depth. Another easy to resolve issue that kills most every year. Again, not really OOA, but without air.
Free Flow is the most common reason I have seen for being without breathable gas. If you have never experienced a full on free flow at depth, it can be a stressful time. It's noisy and the there is a genuine sense of urgency. If you are at 60' and are 'winding down' your dive with 1000psi when this happens, you will have about one minute till your tank is drained. Chances are, you will spend 20-30 seconds composing yourself before beginning ascent, so there is not much gas left for a safe ascent. OOA is a real possibility in this situation, but this need not be the case.
To my knowledge, free flow is not much of an issue in warmer water, but I have seen no less than five, dive ending free flows in the last year.
On the other hand, being without air can happen for a variety of reasons and can be the precursor to any number of bad scenarios if the diver is not prepared.
A second stage could depart from the mouthpiece, for example. Not a big deal to resolve, but it takes composure and the reality of being without air can be a strong contributing factor to panic.
A tank valve might be only partially on, delivering plenty of air on the surface, but starving the reg at depth. Another easy to resolve issue that kills most every year. Again, not really OOA, but without air.
Free Flow is the most common reason I have seen for being without breathable gas. If you have never experienced a full on free flow at depth, it can be a stressful time. It's noisy and the there is a genuine sense of urgency. If you are at 60' and are 'winding down' your dive with 1000psi when this happens, you will have about one minute till your tank is drained. Chances are, you will spend 20-30 seconds composing yourself before beginning ascent, so there is not much gas left for a safe ascent. OOA is a real possibility in this situation, but this need not be the case.
To my knowledge, free flow is not much of an issue in warmer water, but I have seen no less than five, dive ending free flows in the last year.
I agree. Many divers lack a good grasp on their situational awareness.
Short of a sudden and un-foreseen mechanical failure, OOA is preventable if a diver stays alert and has a good grasp on his/her situational awareness.
I would have to agree. Every OOA (including precariously low on air) situation I've seen has been diver error. It comes in many flavors, but even the bare minimum of planning coupled with basic attention to detail would have prevented each and every OOA I've seen.
Equipment malfunction, on the other hand, is always there in the background. It *could* happen at any time, but proper planning and execution preclude significantly dangerous situations from developing. You always have backups for all critical systems. In traditional diving, your buddy carries these, and in other types of diving, you may need to manage your own backups.
I have encountered numerous equipment malfunctions while diving, including twice having yoke valve face O-rings blow. Still, I have never had any equipment malfunction end in an OOA situation. I prepare for it anyway, of course.
I've had one OOA myself, and it was a freeflow. The great thing about that is that you do have time to sort it out; within seconds (if that long) I had two regulators being offered to me.
I've read about at least one OOA due to debris clogging a dip tube in a rental tank.
But it seems as though the majority of them that people write about are due to lack of vigilance -- simply not checking gauges, or occasionally remaining at depth due to the unwillingness of a buddy or DM to surface with a new diver.
I've read about at least one OOA due to debris clogging a dip tube in a rental tank.
But it seems as though the majority of them that people write about are due to lack of vigilance -- simply not checking gauges, or occasionally remaining at depth due to the unwillingness of a buddy or DM to surface with a new diver.
MConnelly2
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An empty tank. That was easy.
Sorry, had to do it or I wouldn't be able to sleep tonight. To be serious, though, which does pain me to do, it is 100% human error. Anybody here who has served or worked underway will understand this already, but it's an odd concept to grasp - anything bad that happens is your fault.
Out of air? Should have managed your gas better.
Regulator fell to pieces? Should have done the proper Preventative Maintenance.
Lost? Should have paid more attention.
Dive boat left while you were still underwater? Shouldn't have dove with idiots.
Absolutely unpredictable, uncontrollable, catastrophic failure of your equipment that nobody could have reasonably expected to occur? Still, you should have used equipment not susceptible to such.
In short, no matter what the issue, it IS STILL all your fault.
Sorry, had to do it or I wouldn't be able to sleep tonight. To be serious, though, which does pain me to do, it is 100% human error. Anybody here who has served or worked underway will understand this already, but it's an odd concept to grasp - anything bad that happens is your fault.
Out of air? Should have managed your gas better.
Regulator fell to pieces? Should have done the proper Preventative Maintenance.
Lost? Should have paid more attention.
Dive boat left while you were still underwater? Shouldn't have dove with idiots.
Absolutely unpredictable, uncontrollable, catastrophic failure of your equipment that nobody could have reasonably expected to occur? Still, you should have used equipment not susceptible to such.
In short, no matter what the issue, it IS STILL all your fault.
The first time I experienced a real OOA situation was at my first dive job. I had just finished my instructor class and taken my first job in St. Thomas. Another guy who had done his instructor class with me but had never been diving 6 months earlier (I had been diving for 5 years but we both went through a 4 month instructor school) took the same job as me.
Our divers were never more than 15 ft deep and we did 3 per trip. This was the second dive out and he tugged my fin and gave me the out of air signal. I thought he was joking because he had been screwing around the whole dive so I just shook my head and kept going. He tugged again and I realized he was serious. I shared air with him and signaled for him to surface (we were only ten feet down at the time). He refused to surface and breathed off of my octopus all the way back to the boat.
If we weren't supervising several guests underwater then we could have just surfaced but I didn't want to leave them all by themselves. These weren't regular certified guests, they were people with no experience that were riding underwater BOB vehicles so leaving them would not have been a good idea, especially since this OOA instructor could have done an easy ESA in 10 ft. of water.
Needless to say the dive manager was not happy with him when we got back. This is why experience in diving is essential to being a good instructor. I may have graduated from a 4 month diving school but I was one of the few there that had prior diving experience.
Our divers were never more than 15 ft deep and we did 3 per trip. This was the second dive out and he tugged my fin and gave me the out of air signal. I thought he was joking because he had been screwing around the whole dive so I just shook my head and kept going. He tugged again and I realized he was serious. I shared air with him and signaled for him to surface (we were only ten feet down at the time). He refused to surface and breathed off of my octopus all the way back to the boat.
If we weren't supervising several guests underwater then we could have just surfaced but I didn't want to leave them all by themselves. These weren't regular certified guests, they were people with no experience that were riding underwater BOB vehicles so leaving them would not have been a good idea, especially since this OOA instructor could have done an easy ESA in 10 ft. of water.
Needless to say the dive manager was not happy with him when we got back. This is why experience in diving is essential to being a good instructor. I may have graduated from a 4 month diving school but I was one of the few there that had prior diving experience.
OP
psychocabbage
Contributor
I personally check my gauges every couple of min.
Excessive? Maybe, but I know I use gas and I like to keep an avg going in my head of how much is being used constantly.
If we shore dive and are heading out, we go as far as 1/2 tank will take us. On the way back in, as we get into the shallows I am less worried about any OOA since surfacing from 12ft should not be an issue..
I would hope most here have had their air turned off during training to see how it is and realize that being OOA is not the end of the world..
Reading through the responses I want to point out again that this is a BASIC thread not advanced or tech.. There should be 0 references to caves or penetration.
We are talking Joe Blow, with C Card out on a dive with either his own equipment or some rental gear.
What exactly could go wrong with equipment? I read above about Freeflow and how fast it will drain a tank at some depth.. Interesting. but even then, you can breathe those last few breathes, remain composed and perhaps signal calmly.. Correct?
I know the diver could be the #1 factor in this equation.. had he been a better more aware diver this may not happen but we have to hope that the diver was trained and has a clue.. Sooo that leaves equipment.
* a freeflow situation (very plausible)
* tank valve popping off??? (highly unlikely)
Excessive? Maybe, but I know I use gas and I like to keep an avg going in my head of how much is being used constantly.
If we shore dive and are heading out, we go as far as 1/2 tank will take us. On the way back in, as we get into the shallows I am less worried about any OOA since surfacing from 12ft should not be an issue..
I would hope most here have had their air turned off during training to see how it is and realize that being OOA is not the end of the world..
Reading through the responses I want to point out again that this is a BASIC thread not advanced or tech.. There should be 0 references to caves or penetration.
We are talking Joe Blow, with C Card out on a dive with either his own equipment or some rental gear.
What exactly could go wrong with equipment? I read above about Freeflow and how fast it will drain a tank at some depth.. Interesting. but even then, you can breathe those last few breathes, remain composed and perhaps signal calmly.. Correct?
I know the diver could be the #1 factor in this equation.. had he been a better more aware diver this may not happen but we have to hope that the diver was trained and has a clue.. Sooo that leaves equipment.
* a freeflow situation (very plausible)
* tank valve popping off??? (highly unlikely)
how does Diving with splits, integrated octos, and quick-release harnesses cause a diver to be in a ooa situation?
and what is a quick-release harness?
and what is a quick-release harness?
jeraldjcook
Contributor
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