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Sounds like the nine failures of doubles. It was taught in my fundies class and reinforced by AG. It was never discussed in any of my non-GUE classes. I teach it as part of my tech classes.
Valve/manifold procedures "in the real world"
- Thread starter AndyNZ
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Fundamentals does not teach failure troubleshooting in part for the simple reason that it is a no-deco and non-overhead course. After you finish Fundamentals and you hear a bunch of racket behind your head, you swim to the surface. Simple. Decompression is taught in Tech I where you will be introduced to valve failures and troubleshooting and decompression.
cfenton
Contributor
cfenton
Contributor
ianr33
Contributor
Silt out in a cave or wreck (Caused by a non DIR diver of course
)While OK'ing the line in zero viz you scrape the ceiling.Lots of bubbles. I dont think thats an impossible scenario.
Personally if I ever found myself in that situation I would go for the isolator first. Provided I close it quick enough I SHOULD be O.K.
So, you're all alone, and you suddenly hear a racket behind your head. What do you do?
You try to determine where the racket is coming from. That includes turning your head from side to side, and reaching back with your hand to try to FEEL the bubbles (which, if they are copious enough to be a major issue, you can do, even with dry gloves). If you can determine the side of the problem, you shut that post. If you CAN'T identify the side, you close the right post, because it's been the one most in action, and most likely to fail. (Note: I would not employ this strategy if I knew, for example, that I had whacked the manifold on the ceiling few times -- then, I'd make a much longer effort to identify the side at fault, and then consider closing the isolator. You really have to give some thought to what might have CAUSED the failure.) If closing the post doesn't solve the problem, you close the isolator and begin your exit, which I would assume is an ascent.
Note that the fact that an experienced diver has had team separation repeatedly does NOT state that this is either a desirable or an unavoidable situation.
You try to determine where the racket is coming from. That includes turning your head from side to side, and reaching back with your hand to try to FEEL the bubbles (which, if they are copious enough to be a major issue, you can do, even with dry gloves). If you can determine the side of the problem, you shut that post. If you CAN'T identify the side, you close the right post, because it's been the one most in action, and most likely to fail. (Note: I would not employ this strategy if I knew, for example, that I had whacked the manifold on the ceiling few times -- then, I'd make a much longer effort to identify the side at fault, and then consider closing the isolator. You really have to give some thought to what might have CAUSED the failure.) If closing the post doesn't solve the problem, you close the isolator and begin your exit, which I would assume is an ascent.
Note that the fact that an experienced diver has had team separation repeatedly does NOT state that this is either a desirable or an unavoidable situation.
rainman_02
Contributor
Separated once.
The other wasn't a separation...it was two teams of two diving together: a lead team and a trail team both going to the same destination from the shore. Team 2 lost sight of team 1 and both teams followed the pre-briefed contingency plan.
The first was a serious situation. There was a good team discussion afterword.
The second was a non-event. There was minimal discussion afterword but it was debriefed.
It is not supposed to happen. But when you're not diving just on the internet, it can happen. Even in DIR diving and the team environment...you should be able to deal with a major problem by yourself. Or did we all forget what we learned in Rescue class (if we took it) -- self rescue is the most important kind of rescue to know.
I'm not saying you should go out and plan / practice for all kinds of multiple contingencies...but have a rational understanding of what can happen in the real world.
DIR, DIW, DWW, whatever...you should never be so dependent upon a team that you cannot self-rescue. You should also understand the limitations of self-rescue (i.e. in a true overhead environment) and know that you may just be up poop creek if you become separated from your team and have a second major malunction.
rainman_02
Contributor
As for the OP...I think it is a great question. One that is answered by higher level training (was covered in depth in my T1).
If you haven't heard of the "9 failures" -- it is a way of grouping the possible failures into manageable sub-sets.
Right Post - Fixable
Right Post - Nonfixable
Right Manifold
Left Post - Fixable
Left Post - Nonfixable
Left Manifold
Left - Sounds Like Right
Right - Sounds Like Left
*** (Unknown)
Now, these are not be-all end-all groupings, but they're there to assist in the "troubleshooting." If you understand what can fail, and what is likely to fail, then you'll find that the "most likely" place to start in an "unknown" is with the right post (unless you can hear/feel the bubbles from somewhere else).
But, within these groupings, there are still standardized procedures for valve shut-downs that cover the various failure possibilities.
Example:
Start with bubbles that sound like they're from your right post.
Signal team (if you're separated...well...uh oh)
Shut down right post; breathe it down.
Switch to backup reg.
Have team check it out (if you're separated...)
Are there still bubbles?
Shut down isolator.
Are there still bubbles?
Etc.
One thing to seriously consider whether you're with a team or not...
If it is a failure of the tank neck o-ring or the o-rings in one side of the manifold...there is nothing you can do about the bubbles until that isolated tank runs out. It will drive you up the wall...the sound of all that gas rushing out and you are powerless to stop it (but hopefully you saved the other tank of gas and are most likely on one teammate's long hose).
If you haven't heard of the "9 failures" -- it is a way of grouping the possible failures into manageable sub-sets.
Right Post - Fixable
Right Post - Nonfixable
Right Manifold
Left Post - Fixable
Left Post - Nonfixable
Left Manifold
Left - Sounds Like Right
Right - Sounds Like Left
*** (Unknown)
Now, these are not be-all end-all groupings, but they're there to assist in the "troubleshooting." If you understand what can fail, and what is likely to fail, then you'll find that the "most likely" place to start in an "unknown" is with the right post (unless you can hear/feel the bubbles from somewhere else).
But, within these groupings, there are still standardized procedures for valve shut-downs that cover the various failure possibilities.
Example:
Start with bubbles that sound like they're from your right post.
Signal team (if you're separated...well...uh oh)
Shut down right post; breathe it down.
Switch to backup reg.
Have team check it out (if you're separated...)
Are there still bubbles?
Shut down isolator.
Are there still bubbles?
Etc.
One thing to seriously consider whether you're with a team or not...
If it is a failure of the tank neck o-ring or the o-rings in one side of the manifold...there is nothing you can do about the bubbles until that isolated tank runs out. It will drive you up the wall...the sound of all that gas rushing out and you are powerless to stop it (but hopefully you saved the other tank of gas and are most likely on one teammate's long hose).
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