No gas -- what do you do?

[daniel f aleman]

Your primary second stage failure may be do to a problem with the first stage - you don't have time to figure it out while hoping that your octo works. So, you just reach for your pony...

 

[Cave Diver]

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.

I have heard (but not personally seen) a lever failure that caused a reg to quit delivering gas. IIRC, it was posted in the Vintage forum here that something was assembled incorrectly (backwards?) during a rebuild and the lever popped loose or broke causing the second stage to stick in the closed position. I *think* DA Aquamaster was one of the people involved in that discussion and mentioned seeing a similar failure as well.

 

[DevonDiver]

I've experienced diagphram failures before. They can tear or fold back on themselves.

I worked at a dive centre in Thailand that stocked an older variant of Aqualung Calypso regulators for rental and courses. They had a very badly designed 2nd stage vent, which did not effectively protect the diaghram when divers conducted a giant stride entry. The shock of impact into the water could cause the diaghram to fold back on itself. This meant that the regulator flooded constantly, preventing use underwater.

It was easy to rectify (poke the diaghram back using a spare zip-tie I kept in my wetsuit pocket). The user had the option of attaining an AAS from their buddy or they could just switch to their own AAS and breath from that.

On the rare occasions it happened, it provided a good learning and discussion opportunity.

Here is another example of a 'non-functioning' 2nd stage that I have actually encountered. A diver turned up on the boat, kitted up, did buddy check...entered the water. On descent they freaked out and sought my AAS. I was very confused about why they did this... they had air and their regulator seemed to be functioning fine. I thought it might be another diaghram issue. The diver was on my AAS and was purging their regulator repeatedly. After a while, they went back to using it...and the dive completed normally. Only after the dive did I discover that a large cockroach had crawled into their 2nd stage and, on descent, had 'woken up' and was trying to get into their mouth. urgh!

That's two examples of when a regulator 2nd stage can become 'unusable' without warning.

I would reinforce that the 'correct' reaction should be to seek AAS. However, I would also remind the divers that they could also use their own AAS providing that they still had an air supply.

 

[Atom]

Here is another example of a 'non-functioning' 2nd stage that I have actually encountered. A diver turned up on the boat, kitted up, did buddy check...entered the water. On descent they freaked out and sought my AAS. I was very confused about why they did this... they had air and their regulator seemed to be functioning fine. I thought it might be another diaghram issue. The diver was on my AAS and was purging their regulator repeatedly. After a while, they went back to using it...and the dive completed normally. Only after the dive did I discover that a large cockroach had crawled into their 2nd stage and, on descent, had 'woken up' and was trying to get into their mouth. urgh!

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.

 

[Blackwood]

Best story ever. All instructors should insert roaches into their students' regs, because wow. Fun.

 

[Belmont]

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 :shocked2:

 

[h90]

The comment was made in another thread that, in the event that your regulator stops delivering gas, you should, as a recreational diver, have the immediate reflex to go to your own auxiliary reg. I found that surprising. I am not aware of a failure mode that will cause a second stage to stop delivering gas, when the rest of the system is functioning normally. As far as I'm concerned, if my reg stops delivering gas, I'm going to signal my buddy immediately and share air.

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

I have seen a broken exhaust valve on a regulator. so it could not be used anymore.

 

[Hoomi]

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.

That would be the approach I'd take, since my backup is right there at hand. If my backup is working, it will be much easier to ascend without having the hose stretched between me and my buddy. If it doesn't work, then there will be no question that I'll need her backup for the ascent.

 

[Trace Malinowski]

I'd signal my buddy then reach into my pocket for my wet notes and credit card. Since trimix is expensive, I'm sure my buddy will ask:

(Question hand signal) Will that be MasterCard (inverted three = M), Visa (peace sign = V) or American Express (Inverted peace sign + E)?

 

[knowone]

That torn mouthpiece or missing diaphragm can cause much displeasure to the uninitiated if wedged somewhere.

Mostly Solo.

The black rectangular triangular tab thing next to the reg inlet is the tape grabber for cover off?