No gas -- what do you do?

[TSandM]

I had a big spider crawl out of my reg mouth piece just before testing it, prior to a cave dive, that was in the jungle in Mexico

I think I would never dive again.

Well, a few accounts of second stage failures where it would simply stop providing gas. All the other failures -- breathing wet, mouthpiece off, etc. -- would be clear indications to switch to own backup. It was the idea of being "out of air" and having the REFLEX to go to one's own backup that I was questioning, and clearly I am not the only one who would not use that strategy.

The comment to which I was responding was in the Tech diving forum, not the solo forum. I have no issue at all with the idea that a tech diver should go for his own backup first; redundancy and self-rescue is a large part of the gear configuration and the problem-solving strategies for technical and overhead divers. I do not agree that this principle is valid for recreational single-tank divers.

 

[DevonDiver]

For recreational diving, I believe that the REFLEX action should be to seek the AAS from your buddy. Once you have secured air, then you can begin the process of analysing the problem and problem solving. If your own AAS can provide gas, then you can switch back to it and complete a normal ascent.

I am a firm believer in the need for in-grained, instinctive, reactions to OOA issues. It is a proven fact that reaction time is inversely proportional to the number of options that need to be considered. This is documented within sports science and widely used within military training.

Whilst an OOA emergency may not have the split-second cruciality that would face a fast-jet combat pilot, or an olympic Judoka in a medal match.... it still remains a very time-sensitive emergency scenario. Fast reaction is imperative. Resuming your air supply quickly is everything. For that reason, I always advise a K.I.S.S. approach to OOA emergency management.

 

[biker pat]

I was once in that situation.
One a line decent at 15 meters I felt my air supply was getting weak.
Checking my pressure gauge confirmed something was wrong.
I signaled my buddy Mike, a master diver that I was out of air.
Same time i pressed the purge button on my octopus to find out that no air. So logically I did not try to breath of my own octopus. Meanwhile Mike had handed me his Octo. He checked my tank valve, but that was open and no leak.
We than did a buddy accent with a 3 min stop at 5m.
On the surface I inflated my BCD by mouth.
Did I panic... yes, but controlled, I was worried but knew exactly what to do.
Even if my buddy had taken to long, I would have dropped my weights and surfaced.

Did I learn something Yes... train, train and train again for all these situations that do never happen....

How could this happen? A faulty first stage from the dive center... now I have my own equipment and take care of it, coz it is my life.

I am very happy I have very experienced diving friends, who dont bend the rules....

 

[waterpirate]

This past season I had a "crack develop" in the body of the oceanic regulator I was using which made it deliver no gas. Purging it delivered gas, but not by breath. All of this took place on the boat while I was pre-breathing the long hose. Other than getting heat stressed in my dry suit while I changed out my primary second with a loaner, no biggie. My solution, switch to bungeed back-up if in water.
Eric

 

[String]

Is anybody else aware of a failure mode in any reg other than an upstream regulator, that will cause a 2nd stage to stop delivering gas?

Ive seen it twice. Once was put down to debris in the hose but im not really sure i believe that given the size hole and filters.

Diaphragm torn means it delivers gas but pretty much 100% water too and thats the most common one ive heard of. Have also heard of the actual spring/level in second stage getting loose to the point it wont open properly.

As i said, very very rare but can happen.

Would anybody else go for their own backup reg, before requesting gas from a buddy? (NOT talking about people who carry pony bottles here.)

Because sadly people aren't trained to think of that. Most rec agencies would probably rather bolt 'n' pray!

My own take is i go for my backup reg (even on singles although im usually on twins). Failing that i'd go for someone elses. I would not ever CESA.

 

[DA Aquamaster]

Well, a diaphragm failure is going to cause you to take on water . . . in that case, I WOULD go to my alternate reg. I was talking about a sudden and complete lack of delivery of gas to the mouthpiece. Can anybody think of a failure that will do that, and not deliver water instead?

Okay, Thal, I posted while you were writing. There's one.

Here is what I have personally seen with dive buddies or customers bringing regs in for repair:

1) The lever becoming obstructed by ice formation in the second stage while ice diving preventing the lever from lifting the seat off the orifice and resulting in a failure to deliver nay gas. (This was doubly fun as it was in a FFM - underscoring the need for an octo and a back up face mask if you are diving a FFM.) This did not used to be a issue with metal cased second stages but with plastic cases and plastic air barrels it is much more common.

2) The tabs on a lever spreading and allowing the poppet to jump past the lever, making it impossible for the lever to lift the poppet and seat off the orifice, again creating a failure to deliver gas.

3) Loss of the retaining nut on an unbalanced dual adjustment design second stage, causing loss of the lever and a failure to deliver gas.

4) gravel in the second stage blocking movement of the lever and causing a failure to deliver gas.

So...it can happen, not often, but perhaps enough to make it worth your while switching to an octo if the buddy's reg is not immediately available.

Something to consider though is that in this type of failure, you usually discover it just after you have exhaled and gotten nothing back, so you don't want to exhale whatever you have left in your lungs clearing the octo, so train to make the switch and clearing via the purge.

Flooded regs can happen just as quickly due to a cracked case, torn diaphragm or folded over/failed exhaust valve and again bailing out to the backup second stage will resolve the problem.

 

[MXGratefulDiver]

This is so wrong!!!!! :shocked2: And now because of you I will never be able to go diving without checking for the presence of a cockroach in my regulator... and maybe wondering if I did it properly during the dive... fortunately my next dive will be during winter, no chance for the bug to survive in subzero weather.

Guess again ... I think a cockroach might possibly survive a nuclear holocaust.

Around here we don't get cockroaches in our regs ... but I have seen a spider crawl out of one once ... :shocked2:

... Bob (Grateful Diver)

 

[Muddy MO]

You can signal your buddy at the same time you pop in your secondary reg... If that reg also doesn't work, your buddy should now be ready with one you know does.

Same thing I was thinking

 

[knowone]

.

Something to consider though is that in this type of failure, you usually discover it just after you have exhaled and gotten nothing back, so you don't want to exhale whatever you have left in your lungs clearing the octo, so train to make the switch and clearing via the purge.

Flooded regs can happen just as quickly due to a cracked case, torn diaphragm or folded over/failed exhaust valve and again bailing out to the backup second stage will resolve the problem.

Yep.
Very good.

 

[40Fathoms]

I'm all for trying your own secondary, but my first instinct would be to get a reliable source air secured, then try other options. So, I'd signal my buddy, and make getting his/her secondary a priority, then try my own secondary. My DM trainer always said "as long as you have air, there are no problems, only stuff you need to figure out how to do".