Made an out of gas ascent today

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sea_otter

Contributor
Messages
331
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Location
Pacific Grove, CA
# of dives
500 - 999
I had a bit of unplanned excitement diving today, and I thought the story was one worth sharing. After all, it isn't every day a buddy runs out of gas.

We had a team of three, I was #1, my planned dive buddy was #2, and #3 joined our team.

We were on a recreational GUE charter diving a couple sites in the Monterey Bay, which locals will know as Anchor Farm and Shale Island. While the conditions weren't great, these are both pretty easy dive sites, even in poor weather.

The Anchor Farm is a small site on a flat sandy bottom around 80 ft, where a couple giant anchors form an artificial reef. It's covered with metridium anemones and provides a home for rockfish, lingcod, sculpins, and greenlings.

While the emergency happened on the second dive, our challenges actually began on the first dive, so I'll start my story there.

After a quick check, the three of us jumped in, swam to the bow of the dive boat, and prepared to descend the anchor line. I signaled OK, received affirmative responses, and then signaled to descend. I descended, but the rest of the team lagged behind getting flashlights turned on and ready (Mistake #1 - don't accept OK if people aren't actually ready). I waited on the line about 7 ft below the surface. Visibility wasn't very good, probably 5 ft max. I had sporadic visual contact with my team, but eventually I saw them starting to descend. I momentarily lost the line while looking above me for the others. I spotted them and found the line again, being careful to keep visual contact with the line and occasional visual contact with my buddies. (Mistake #2 - I could have just grabbed the line and focused on the team.)

I reached about 40 ft and found myself with buddy #2, but I didn't see buddy #3. I figured maybe he was in a blind spot directly above me, and it'll sort itself out when we reach the bottom. We descended past 50, 60 ft. I looked up and couldn't see him above me, and I started to worry. There were a few divers below me, though, so maybe one was him, even though I definitely hadn't seen him pass. (Mistake #3 - failing to descend together, and continuing to descend after noticing a problem.)

We reached the bottom of the ocean, and there were a few other divers there. I swam close to identify each one (crappy vis persisted down here too). None of them were my missing diver. I asked #2 if she had seen #3. She shrugged. I thumbed the dive and we made our way to the surface. The ascent was slower than it should have been (particularly given we had a lost diver), progressing at about 10 ft per minute all the way from the bottom (80 ft). I signaled to continue up from 20 ft without additional stops, but my dive buddy pointed to her computer. We stayed an extra 2 minutes to complete a safety stop. After a total of 10 minutes, we finally reached the surface. With the delayed descent, search at the bottom, and the slow ascent, we were separated for almost 15 minutes.

I asked the boat crew about our missing diver, and they confirmed he was safely back onboard. They mentioned he had been struggling with buoyancy due to overweighting.

I went back down with #2. We stayed together on the descent this time, enjoyed the site, and when it was time to call the dive, I made a specific effort to properly time the ascent. I closely followed a defined schedule - 30 ft per minute to half depth, 10 ft per minute from there (with an extra minute at 20). I was quite happy with the practice of a "textbook perfect" ascent, following the schedule to the second.

We returned to the boat and chatted with #3. Most of his recent diving had been fresh water, and he had overcompensated by adding too much lead for the ocean. He didn't have any detachable weight (just a single big piece of lead and a steel backplate), so he decided to mitigate his weighting issue by draining his tanks down to 2000 PSI. Even though we're doing recreational single tank profiles, most of the divers on this boats bring a single set of doubles to use for two "single tank" dives. (In hindsight, this was Mistake #4. Gas is a terrible thing to dump when you are too heavy.)

Our second dive was planned at Shale Island. This is an oval shaped shale ledge around 55 ft. Lots of slugs, sculpins, fringeheads, and other cute little critters live beneath the ledge. The route around the "island" (it's a flat structure, with a high point of 50 ft) is about 1200 ft long and takes 30-45 minutes to circumnavigate at a slow leisurely pace. We all had enough gas for at least an hour at that depth and expected to take 45-50 minutes to circle the island. Since our planned path was a circle, we did not discuss turn pressure.

We descended the anchor line, doing a better job of staying together, and we ventured out around the shale reef. Most of the dive was uneventful, but I did notice that #3 was not diving as well as he normally would. I noticed little stuff, like him struggling with horizontal position and occasionally reaching out to touch a rock. I attributed it to the overweighting and refrained from mentioning it. It didn't even cross my mind that it could be a sign of stress (Mistake #5). At one point, I saw him fiddling with his valves. Instead of immediately asking what was going on, I thought "hey, good idea. Let me do a quick flow check to make sure I can comfortably reach my valves." (Mistake #6). At that time, I had no idea that he was specifically checking his isolator, wondering why his SPG wasn't moving.

Shortly thereafter, a little over 40 minutes into the dive, #3 turned to me to signal low on gas. I was confused, and I gave him an exit signal pointing in the direction of the boat. I knew we weren't very far from the anchor. He said no and gave me a thumb to end the dive now. I reached into my pocket to pull out an SMB, but as I was doing so, he signaled out of gas. I stopped what I was doing with the SMB and immediately gave him my long hose. I unclipped my SPG to check gas and show it to him; we had 1200 PSI in my doubles, plenty more than what we needed for minimum gas. Seeing the SPG and receiving the affirmation that we had plenty of gas and plenty of time dissolved all stress of the moment. (This step of showing the SPG to your buddy isn't taught by GUE, at least not in recreational classes. I am really thankful that my cave instructor had drilled it into my process flow - she tends to appear in my head any time I'm having trouble underwater.) I shot the bag and we started up. (I debated asking #2 to take care of the bag, but she didn't volunteer after seeing mine was already half dangling out of my pocket. I should have at least handed it to her after it was deployed. Mistake #7 - use the whole team.)

We made a safe and relatively uneventful ascent sharing my gas. I did struggle a little bit with buoyancy as we neared the surface, realizing later that I had forgotten to bring a two pound weight I normally wear on my hip. (Mistake #8 - I didn't even bother to check because I normally have enough reserve gas in my doubles where I can get away with diving a little underweight.)

We reached the surface with 900 PSI in my tanks, and we chatted about what happened. #3 said his SPG was stuck at 2000 PSI, but his right tank was empty. Sure enough, I checked the isolator, and it was fully closed. (Mistake #9 - This was checked pre-dive, but instead of opening it all the way, he accidentally closed it all the way. And Mistake #10 - We had been sitting on opposite ends of the boat, so there was no buddy visual confirmation on the pre-dive valve check.) While it would have normally been pretty obvious to blame a closed isolator, his SPG had been reading a few hundred PSI off in the past few weeks and really needed to be replaced, so he assumed it was to blame and worried more gas than intended was drained after the first dive attempt (Mistake #11 - getting complacent about fixing equipment). He didn't think of checking his own necklace in the moment, and neither I nor my other teammate had any idea what was wrong until we reached the surface.


Everything worked out fine in the end, and we all smiled and laughed afterwards. Nonetheless, I thought it was an interesting story worth sharing how a bit of complacency, communication gaps, and mixing up lefty loosy righty tighty can add up to some major problems. I am thankful that my training and practice kicked in when I needed it.
 
Thanks for sharing, I never thought of showing a SPG after giving a reg: that seems a good technique to reassure the OOG diver. Thank you.
 
Isolator valve strikes again.

I'm not a huge fan of the indicator valve knobs, but it's a quick sanity check for isolators on if they're open or closed
 
I don’t think there is a good reason to close them in normal usage except if you do a drill.

Also it’s worth checking mentally your sac rate by looking at your SPG to see if your gas usage seems in line with expectation.

If your sac rate seems to be 0, 10 minutes in a dive, either you became a fish or your isolator is closed. In this case, the diver made the conscious decision to dive with a faulty SPG so he couldn’t know his gas consumption …
 
In this case, the diver made the conscious decision to dive with a faulty SPG so he couldn’t know his gas consumption …
Small correction - he made a conscious decision to do an easy recreational dive with a SPG that was accurate but not precise (e.g. 100 PSI low, consistently). I suspect that's a risk most of us would be willing to take. I can also easily understand the thought process in jumping to the wrong conclusion (I knew it had a minor problem, so now it's easier to believe that it has completely failed in an unexpected manner).
 
Thank you for the writeup! I hope you don't mind if I ask a followup question...

The ascent was slower than it should have been (particularly given we had a lost diver), progressing at about 10 ft per minute all the way from the bottom (80 ft). I signaled to continue up from 20 ft without additional stops, but my dive buddy pointed to her computer. We stayed an extra 2 minutes to complete a safety stop. After a total of 10 minutes, we finally reached the surface. With the delayed descent, search at the bottom, and the slow ascent, we were separated for almost 15 minutes.

What was going on here? I know GUE has its own ascent protocol, which I guess you were intending to follow (on the second dive at least), but a) why so slow under the circumstances and b) given that ascent protocol, why the pointing at computer and stuff from your buddy? It can't reasonably have been an NDL issue so I'm guessing it was that the computer indicated a safety stop, but isn't that outside the normal ascent procedure?

he decided to mitigate his weighting issue by draining his tanks down to 2000 PSI

That's ... a choice. 😯
 
Small correction - he made a conscious decision to do an easy recreational dive with a SPG that was accurate but not precise (e.g. 100 PSI low, consistently). I suspect that's a risk most of us would be willing to take. I can also easily understand the thought process in jumping to the wrong conclusion (I knew it had a minor problem, so now it's easier to believe that it has completely failed in an unexpected manner).
Well if that’s the case he made a bad decision to not abort the dive when the needle didn’t move.
 
Isolator valve strikes again.

I'm not a huge fan of the indicator valve knobs, but it's a quick sanity check for isolators on if they're open or closed
If I understand correctly, the diver checked the position of their isolator during the dive and apparently decided it was open (or turned it to what the diver believed was the open position). A Vindicator wouldn't have helped there.

I recall an instance in cave class where I was helping my teammate with a simulated reg failure, and I decided my teammate had erroneously closed the isolator, so I helpfully "opened" it. I had inadvertently closed it. I have manipulated my valves hundreds of times--flow checks before and during dives, shutdowns and diagnoses during simulated failures, etc.--and for whatever reason, this time I had a brain fart and turned my teammate's isolator the wrong way. Fortunately, in a team of two there are two brains at work, and in a team of three, yet another, so the likelihood of an error like mine not being caught is low. But still. It's a bit unsettling to find that a diver can have done this a hundred times and still make a mistake turning a valve the wrong way.
 
Sounds interesting. I am surprised that you took 10 minutes to ascend from only 80 feet after spending less than a minute on the bottom. The guy will be dead on the bottom by then, might as well just stay down, I suppose.

I am also surprised about the protocol followed when someone gives a low on air sign. I would immediately ask to see the gage and show them mine, not do other stuff. If there is a problem that requires an immediate ascent, I want everyone to know what kind of resources we each have, although a stuck gage could give a bad reading.

Anybody who has no ditchable lead and dumps air from their tanks (on the boat) to make themselves lighter (because they are too heavy to dive) is not someone I would choose to dive with. I find it humorous that people might think "buddy" diving with someone like that is safer than diving alone.

The apparent widespread practice of carrying no ditchable/adjustable lead is still amazing to me; an old school weightbelt would have addressed this issue easily, rather than encourage people to dive less safely.

Glad to hear you all made it back from 55 feet with 3 sets of double tanks and only a little trouble, sounds like the training really kicked in.
 
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