Strange event, no air

[tursiops]

That is their current recommendation. Since most computers recommend 30 FPM, PADI's recommendation is in effect 30 FPM.

Their current recommendation is explicit: go no faster than 60, or slower if your computer requires it. And do safety stops.

 

[johndiver999]

Wow, thanks for the story. Something I have never hear of. Is it possible someone placed two orings on the valve face somehow?

If that were me, I also would not have been too freaked out, but I would be going directly to the surface, with zero consideration for stops.

I guess if your buoyancy is right and you feel confident, I see no problem in doing a safety stop, solo in the dark with no air... I guess., LOL

I think in that situation, I would immediately press the up button (on the BC) and tried to get slightly positive, perhaps before I even tried an alternate second stage. I'm sure I would be very unhappy if the inflator also gave me no air into the BC and I would be kicking and swearing.

 

[crofrog]

I broke some rules, I let my buddy get off. And this being the second time I have had an event while group diving where the group decided to leave me . Along with my buddy. That is on me, my fault.

I’d say it’s the other way around. Your buddy is at fault. You have to stay together and if someone stops you have to stop too.

 

[BRT]

Wow, thanks for the story. Something I have never hear of. Is it possible someone placed two orings on the valve face somehow?

If that were me, I also would not have been too freaked out, but I would be going directly to the surface, with zero consideration for stops.

I guess if your buoyancy is right and you feel confident, I see no problem in doing a safety stop, solo in the dark with no air... I guess., LOL

I think in that situation, I would immediately press the up button (on the BC) and tried to get slightly positive, perhaps before I even tried an alternate second stage. I'm sure I would be very unhappy if the inflator also gave me no air into the BC and I would be kicking and swearing.

I have seen people use an extra o-ring to get a tank to seal.

 

[Cthippo]

Thanks for posting.

I am always curious what the actual failure points are in equipment and you did an excellent job explaining what went wrong. Appreciated!

 

[2stroketony]

I am going to post this in Basic, if it needs to be moved, please do. So then, I was diving a just serviced (by me) G250, brand spanking new Mark 11 (around 50 dives since new) and new DGX BCI on a night dive in Cozumel, Paradise Reef. Shallow, maybe 30 feet, 40 maximum maybe. Dive was going well seeing the usual critters and on the look for the elusive octopus. Nothing unusual. Nitrox 32% mix, regulator performing wonderfully for previous four days. I found a little critter and began to photo and of course, my group moved a little off due to the current. I decided they (and buddy) were getting too far so I left the critter and began moving their way, not that far. Noted my spg was reading 1200 psi so I wanted to group up before ascent. Then no air, none. Just like that. The last breath, I may have noted a flutter but thought nothing of it. Hmmm, well, hmmm. A moment of disbelief, third dive of the day so I did want to do a bit of a safety stop. Am I imagining this? Inhaled again, absolutely nothing. Okay, let's not delay switching regs like in my other event (not going into here from a few years back, much deeper though) so I went to my BCI, got one little bit of a breath and nothing. Started up. Got to 15 feet, now about a minute since last full breath. Checked my Shearwater, it was in safety stop and was counting down. Tried to inhale again and got another little bit of air. Now about a minute and half since last good breath. I wanted some air really bad by about then so now at 2 minutes approximate since last breath I decided to surface and hit the surface I would say at 2:15 since last breath. Hit inflator button and very little to nothing. Spit reg out and clipped it off, took some sweet breaths, orally inflated and just hung there a moment resting and ventilating and mulling the event over. Boat swung over and picked me up. Tank was at 1000 psi on the boat. Double checked with another regulator with both spg and AI, 1000 psi! No doubt. Oh, yes, we did check the valve to be full on and it was. No roll off, no partial valve. And with the reg removed air flowed from the tank as normal.

It being dark now I did not see anything wrong and after turning the tank valve on and off the regulator began to function again but with a huge spg drop with each cycle. So I get back to the room, toss the reg aside and grab my Mark 17E and G260 set for the next day of diving and went to eat. Next day after dives complete I got back to looking into what went wrong. Guess what I found? Two things actually. One, the LP regulator hose was loose and the O-ring was partially extruded but not leaking. Then I looked at the regulator sintered filter to see if there was some sort of crud or FOD. Yep, there it was, a destroyed tank O-ring was completely shoved into the cone of the sintered filter obscuring the inlet of air.

So, there was an O-ring on the tank and it passed pre dive leak check. Pre dive spg check there was no unusual spg drop or indication nor during the 45 minutes in the water until the sudden no air event. So where did the O-ring come from, well, beats the cxxp out of me because it was NOT in there before the dive. The tank O-ring was in place before, during and after event. My two guess are that the O-ring may have come from the previous tank when the crew blew out the cap and that it was not seen in the dark when the regulator was installed and then somehow getting into the filter cone? Or, at the fill station an O-ring was accidentally shoved into the valve during fill and was in the valve dip tube and that the "flutter" I noted on the last good breath was that O-ring being shoved into my regulator filter. Or, I am at a loss.

After several tests and checking the Mark 11/G250/BCI on a near empty tank the regulator was performing normally and I resumed using it. Of course having removed the destroyed O-ring. The cleaning custodian unfortunately wiped the counter and I do not have the O-ring. I guess if one dives long enough weird things can happen. It was not such a big event due to being on a shallow reef with no deco obligation. Had I been on the wall, in a deep swim through, who knows. I do look at and check my regulator prior to diving. In the dark I guess I did not see the O-ring there but that is unlikely therefore I favor the hypothesis that the O-ring was not there but was inside the tank. Because I did look, but, you know, I did not have my glasses on, it was getting dark, everyone was ribbing each other, the usual distracting fun banter we all love. So -----.

My take aways:

Check filter before installing the regulator
Check hoses tight during pre dive checks
Make sure valve is full on
Test for spg drop when cycled
XHopeX there is no FOD in the provided tank

Well, we could dive doubles always or have Y valves with two complete regulators or have an auxiliary pony bottle type system. I am not advocating for any of that. Or keep your buddy at arms length. That right there is on me because the critter was much more cute than my sorta-buddy and I wanted a good picture, which turns out the photo sucked as usual. There you go.

Nemrod

Thank the Lord you weren't too deep.

 

[Nemrod]

Thanks for posting.

I am always curious what the actual failure points are in equipment and you did an excellent job explaining what went wrong. Appreciated!

Thanks, this type of failure has really never occurred to me. I am really perplexed by how the O-ring got there and how it so completely occluded gas flow. It was certainly confusing in the moment which is one reason I futzed about for a bit to clip my camera off to free my hands so I could ensure the valve was fully on, I thought I had a roll off or the valve was not fully on. But the valve was fully on. Occam's Razor, the simplest explanation and I am not satisfied, what is the simplest explanation? Several people have told me the O-ring wadded up in the filter could not have shut gas flow off, I was and am skeptical myself. But, well, it was about a 96% shut off, not even enough to inflate my wing. Post dive, after cycling the air off, purging, and then back on, the regulator did flow but with a large needle swing.

The Mark 11 is on the bench now. I intend to take it down and check it out. However, I did return to diving the Mark 11/G250/BCI and it performed excellent for the remainder of the trip. It has about 70 dives now since purchase last spring so perhaps not a waste to do a tear down and inspection.

I do not believe that the extruded O-ring on the loose LP primary hose to regulator connection had any effect. It was not leaking. Nobody does an hour dive at 30 plus feet with a leaking LP hose connection sufficient to prevent air flow to the second stage and still have 1000 psi on the boat verified. A LP leak that was enough to inhibit air flow to the primary would have certainly been noticeable and quickly emptied the cylinder, you would think. So the loose hose is therefore a distractor to the cause.

 

[TravisD]

I have seen people use an extra o-ring to get a tank to seal.

Yikes! That's not how o-rings work, and will frequently lead to a failure. I'm not even clear how that would even work on a typical yoke valve -- I have enough trouble sometimes getting a single, correctly sized o-ring to seat in the groove long enough to get a reg on to fully seat it.

 

[BRT]

Yikes! That's not how o-rings work, and will frequently lead to a failure. I'm not even clear how that would even work on a typical yoke valve -- I have enough trouble sometimes getting a single, correctly sized o-ring to seat in the groove long enough to get a reg on to fully seat it.

Not my way of fixing it, but I have seen it work

 

[Eric Sedletzky]

I used to free dive. I am in pretty good shape for a 70 yo. I also breath hold practice while swimming laps. Of course do not tell the Y guards because that is against the rules! I say used to free dive because a long, long, time ago, spearfishing on the rigs in Louisiana I had a near SWB event, I mostly just grayed out. I had descended to about 80 feet and speared an amberjack. We had safety divers and one immediantly came to my aid. Anyways, that is off topic, I decided that was not my cup of tea, but regardless, the point is I do train to survive short periods without air. Freediving to 30 or so feet is not a big deal for me, so, OOA at 30 feet, not desireable, mostly annoying. At 60 feet or more I would have been in (big) trouble holding everything else equal and the same. For a new diver, at night, yeah, could have been bad. So adjust your considerations to match your realistic capabilities and experience. Everyone, anyone, can and will eventually panic, well, maybe not but if there is an OOA malfunction and no back up in form of a buddy or alternate system, what does it matter if you calmly die or bolt to the surface, deceased is still deceased.

Blow and Go baby!
At 60’ and suddendy no air, no buddy, no pony, at night, screw it! That would be one time at depth that I’d strongly consider dumping my weights if I had to and going for it.

Alive is fixable, dead isn’t.