Reminder about unavoidable OOAs

[Xman]

Well, I had a scary experience yesterday which could have been a whole lot worse.
I was diving at the Alderman Islands off the east coast of New Zealand. We had already been down for 1 dive, and I had switched tanks and was preparing my gear for the next dive. When I opened my valve to turn on my air I heard a the air fill the hoses, then heard a rush of air as though the tank o-ring had gone. That lasted for less than a second before there was a loud bang. I quickly shut off my air, and had a look to see what had happened.
My first stage (Scubapro Mk20) had blown itself in half. The lp end (swivel end) had blown clean off the hp end. I can't stop thinking how that would have been underwater. I know there are a number of reasons other than poor gas management why you would end up OOA, but I had never seriously considered that one. I trust my dive buddy and feel sure that we would have coped had this happened underwater, but I am glad I didn't have to find out the hard way. Thinking, if it blew between breathing out and breathing in, I could well have breathed in a mouthful of water. Controling the coughing, and sorting myself out to share air with my buddy would not have been pleasant.
Lessons learned:
*You never know when a gear failure might leave you OOA with no warning.
*Don't trust swivel first stages.

 

[gle]

When the swivel blew, did it allow air to escape? In other words, would it have turned you into a bottle rocket?

 

[Xman]

Yes, when the swivel blew, the air was coming out as fast as it would be if you had no reg on the tank and opened the valve.
For clarification: the first stage blew apart literally. It ended up in two seperate parts. The LP swivel with primary and alternate regs and inflator hose blew off and was completely seperate to the rest of the first stage (which remained attached to the tank).

 

[Diver0001]

Have you contacted Scubapro about this yet? I bet they'd be very interested in inspecting your reg.

R..

 

[liberato]

It's always good to be reminded that hardware failures do actually occur and that one has to be prepared. I am pleased that it happened topside so that it only becomes an interesting cautionary tale you will be able to tell and re-tell.

 

[Xman]

Have you contacted Scubapro about this yet? I bet they'd be very interested in inspecting your reg.

R..

No, not yet but I am definately going to. I've never een heard of this happening before. Anyone else out there heard of a first stage failing in this way? Pretty scary stuff.

 

[Xman]

Here is a picture of what my first stage looks like now that it is in 2 parts-

 

[Tom Smedley]

Xman - Did the bolt that holds the two parts together shear off or did it work itself loose? This is a catastrophic failure point and the bolt is usually held in torque with LockTite. It will be intersting to know what happened to it.

 

[Chuck Tribolet]

Thinking, if it blew between breathing out and breathing in, I could well have breathed in a mouthful of water. Controling the coughing, and sorting myself out to share air with my buddy would not have been pleasant.

It's less likely than you think that you would have breathed water through the hose. Remeber you would have had to suck it through hose, which would have been more
difficult than sucking air, and would have taken a second or so. And you would have
had to suck the second stage open. Go try breathing through the second stage now,
while the reg is in two pieces.

These failures are more likely when you turn the tank on (highest tank pressure).

I'm with Tom: Did it break or come unscrewed?

When was the reg last serviced? If, say last week, that's NOT who you want to look
at the failed reg. In any event, get a competant neutral third party to look at it
BEFORE it gets sent off to the manufacturer. And get real closeup pictures of any
thing that broke.

 

[Diver0001]

No, not yet but I am definately going to. I've never een heard of this happening before. Anyone else out there heard of a first stage failing in this way? Pretty scary stuff.

I've seen something similar happen with an aqualung calypso but in that I case it was clear that the A-clamp was loose. If it really "broke" off then it's obviously much more serious.

R..