No gas -- what do you do?

[300bar]

As I just posted in another thread:

I was diving at Pt. Lobos, CA with my Assistant Instructor. We were at about 40 FSW, 15 minutes into our dive. My buddy, after signaling me, took off in pursuit of a large Eagle Ray, I was along side of him, about 2 feet back. He suddenly stopped, spat out his regulator and pointed to his mouth (signaling me to buddy-breathe). I gave him my regulator and we settled into a two-breath-each rhythm while maintaining our neutral buoyancy. We were under a very dense kelp canopy and had to buddy-breathe while traveling about 100 yards to a point where we could surface. We did so without further incident, surfaced, returned to our surf mats and to shore. Later examination of his regulator second stage showed that he had bitten off a tab from his mouthpiece and it had lodged in the regulator behind the actuating lever in such a fashion as to cut off his air supply. After some experimentation I found that in this circumstance, if I attempted to depress the purge button I could feel it stick and that if I sharply stuck the second stage it would then function.

NO alt air.
Instructor AND assistant instructor.
Nice example.:shocked2:

 

[Rainer]

You're obviously not comprehending the situation. I deployed a regulator, at which point, while my hand was on the second stage, the diaphragm cover came off (or just wasn't there already). Gas flowed while my hand was still in contact with the front of the (now bare) regulator. When I removed my hand, gas stopped. That second stage was rather useless. I finished deco on a different reg. If that's still not clear for you, please PM me.

No diaphram will cause a gas flow.
Not possible, no diaphram means the lever will not be depressed, so no gas flow.

Now run line, scooter to the exit, pull your reel, deploy Jon line or hold onto anchor line, while dumping gas, then switch to a deco bottle, all one handed. Might work for the diving you're doing; wouldn't work so well for the diving I'm doing. If I have a mouthpiece fall out, I'm simply switching regs, not doing a needless hand dance.

Had on hand on my light and the other on my alt air, so yes can be done.

 

[Bubbletrubble]

I think divers would benefit from spending a few minutes learning about how regulators work.
I learned a great deal by doing DIY overhauls on my own regs.

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.

@TSandM: Broken or severely bent lever.

 

[MXGratefulDiver]

Ask Rainer, it was his. But as he mentioned above, we don't know how it happened. We arrived at 70 feet, and when he went to deploy deco gas, there was no face plate on that second stage, nor was the diaphragm in place.

I saw that failure occur once ... to a fellow who was in the habit of not clipping off his long hose. I suspect the second stage ended up on the ground ... perhaps got stepped on ... and subsequently damaged ...

... Bob (Grateful Diver)

 

[udtfire]

pony pony pony

 

[Saltwater Junky]

Signal buddy OOA, share air and surface.

 

[Blackwood]

I deployed a regulator, at which point, while my hand was on the second stage, the diaphragm cover came off.

Or that. From my vantage point, I never saw the cover. I just saw the lever when you showed me and Kim the regulator.

I saw that failure occur once ... to a fellow who was in the habit of not clipping off his long hose. I suspect the second stage ended up on the ground ... perhaps got stepped on ... and subsequently damaged ...

... Bob (Grateful Diver)

Not this time. It was a (properly) stowed reg on a deco bottle that worked on the previous dive and when it was put on the full bottle. It probably hit the wreck we were diving, but I don't know for sure.

 

[300bar]

Ask Rainer, it was his. But as he mentioned above, we don't know how it happened. We arrived at 70 feet, and when he went to deploy deco gas, there was no face plate on that second stage, nor was the diaphragm in place.



Bubbles everywhere because he hit the lever with his finger, and there was no diaphragm to contain it the flow of gas.

That explains your problem, but IMO not what the OP asked.
Still wierd that a faceplate can get lost.
Sound like user error to me.

 

[redacted]

2nd stage failure to deliver gas is rare so I go for my buddy or my pony if solo. Any case integrity failure would deliver water. A failure of the lever or lever interface would deliver nothing.

 

[Atom]

NO alt air.
Instructor AND assistant instructor.
Nice example.:shocked2:

Considering he's been diving for a long time, it was probably before alternate air source became a standard part of the kit.

And +1 on checking your alternate while signaling your buddy to share air. There might still be a puff of air in that hose but probably not enough to cover the purging + another breath... hummm... anybody tried that?