Two Dives, Two near Emergencies, Lessons Learned

I had two dives today, in beautiful Port Elizabeth South Africa, and things didn't go as well as one would hope. I wanted to share my experiences, and the lessons I learned from those experiences.

First Dive:

Max planned depth 29 m
Actual dive depth 25 m.

I hadn't slept well the night before, and I suffered for it. My buoyancy control was really off, and my breathing was horendous. We had planned to do a blue-water ascent at 70 bar or NDL, whichever came first. We had lost the rest of the buddy teams, so we had taken on the divemaster as our third. This was all discussed ahead of time, so no big deal. Actually, I am not sure why the divemaster didn't have a dedicated buddy team to be with, and I will suggest that tomorrow during my next dives. At 1100 PSI (just over 70 bar - my gauge is imperial), I signalled time for me to ascend. My buddy, and the divemaster, ascended with me. We did a deep stop (required by the divemaster's computer), and at 1:30 into the safety stop, my tank went below the IP. I have an unbalanced second, so there was sufficient warning, and I signalled, and did a normal ascent as per my training for a low on air situtation. I was still breathing air from my tank, and able to inflate my BCD when I surfaced. I wasn't at all scared during the whole incident but it did make me really think about the things I had done wrong, and the things I had done right.

Things done wrong in my view:

When I noticed my breathing was off, I should have adjusted my end-of-dive pressure to compensate. I was in a thick wetsuit, and with my buoyancy being off a little as well, I should have predicted that I would use a lot more air than planned doing a safe ascent. Next time: If factors come into play that may increase my ascent time, adjust the end-of-dive pressure.

I was too busy watching my depth guage at the safety stop to glance at my SPG. I should have been watching it more vigilantly. I was fortunate that I got the warning from my unbalanced second when I was close to being out of air. Next time: Watch my SPG more closely during my ascent, and stop

Things done right in my view:

I maintained very close contact with my buddy, and the divemaster throughout the dive. Had I actually gone OOA, an alternate air source would have been right there. I think the close contact helped me to stay calm during the situation.

I followed my training to the letter, and did a normal ascent when I was low on air, ignoring the rest of the safety stop as it would have put me in greater jeopardy.

Things I am not going to change:

I am going to continue using an unbalanced second with a balanced first. I normally watch my SPG pretty well, so the time I would need warning would be exactly when it happened, at the safety stop, when I had just enough air to safely ascend from the stop. With an unbalanced first, the warning would have come way to early, and with a balanced second, it wouldn't have come at all.

Second Dive

Planned Max Depth 15 m
Actual Max Depth 12.5 m


My breathing and buoyancy were much better on this dive. It was like I was a whole other diver. I continued to stick close to my buddy. At 0:25 into the dive, his primary second stage started taking on water so he switched to his air-2 octo. What I saw was him trying to breath off of his octo while is primary was freeflowing (a usual consequence of putting your primary aside to quickly switch to your octo). I assumed he was in trouble, and despite practising handing over my octo many times, I tried to hand him my primary. He got the situation under control, and refused it. I put it back in my mouth, and we ended the dive.

Lesson Learned:

As it is my automatic response to hand over my primary, I will practise this as my air sharing technique from now on. No point in practising something one way when your in-built response, which is just as good, will be what you are doing anyways. A big advantage of handing over your primary, is that you don't have to fiddle with it to get it in the right position for the other diver. My octo is always in a place where I can immediately reach it without thinking, so it would have been fine.

Sometimes it is the troublesome dive from which we learn the most and grow the most as divers. It sounds like that was the case here. I congratulate you on you responses and refletions. I would note equipment issues, both the malfunctioning regulator in dive 2 and new and unfamiliar exposure gear worn by you in dive 1. I think more familiarity with the equipment used, and a pre-dive check of it- at the shop or in a pool, may have eliminated some of the issues that affected the dives. Keep learning, stay active, and be safe.
DivemasterDennis

I think the big lesson from the first dive is that, when you are in conditions or using equipment that is unfamiliar to you, the first dive should be a very easy and conservative one (which, in my mind, a 90 foot dive involving a blue water ascent is not). I've been enough places now to know that we are all beginners in new environments, and the ocean loves to play with people who have overestimated their capacity

As far as the second dive goes, I'm a little unclear about what happened. Were you using rental equipment that was configured differently from your gear at home? Do you normally use an Air2 or bungied necklace? If the latter, it's not difficult to convert a rental setup to a bungied backup arrangement -- just bring along some shock cord and fashion a fisherman's knot necklace, and hang the reg on the short hose around your neck, and breathe off the "octo". If the dive op has used a lousy regulator for octos, or detuned them badly, then that won't work, but it isn't going to be fun using the octo in an emergency, either.

If I am using more air than usual I keep a sharp eye on that pressure gauge the last 10 min of the dive. Guess I am just chicken huh?

TSandM:

I think the big lesson from the first dive is that, when you are in conditions or using equipment that is unfamiliar to you, the first dive should be a very easy and conservative one (which, in my mind, a 90 foot dive involving a blue water ascent is not). I've been enough places now to know that we are all beginners in new environments, and the ocean loves to play with people who have overestimated their capacity

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I think you are mostly right about this. All the equipment is mine, and I had practised with it in the Quarry at home. I also practised the blue-water ascents with the same equipment. However, I was apprehensive about diving with "Insta-buddies", and I hadn't gotten enough sleep the night before. I think I would have been fine if I was more fresh, but, in the condition I was in, I should have skipped the first dive, and I definitely should have ended the dive early when I had so much trouble with breathing and buoyancy. I will definitely take heed of your advise to do an easier dive the next time I go somewhere unfamiliar. I could only get in 4 dives on this business trip, so I didn't want to skip the first one. And, yes you are reading correctly. I started off partly agreeing with you at the start of this paragraph, and ended up fully agreeing with you by the finish, but I am not going to edit it out. That was my train of thought.

As for the second dive, my buddy had the Air2 (shouldn't have mentioned it in my post as it wasn't really relevant). He had just had his second stage serviced at the manufacturer, so it was really strange that it was leaking water. Because of the initial second stage freeflow, initially, it looked like a more serious situation than it was. I was using normal second stages on my own regulator set. I was more just commenting on how I had planned during practise to share my octo, but instead ended up trying to share my primary. If that is what comes natural to me, I ought to practise it that way, and maybe get a bungeed octo necklass.

Ah . . . I thought you were saying that you normally donate the primary, but for some reason were diving a setup that wasn't designed for that. If your first reflex is to offer the primary, by all means set your gear up to do that. It works real well.

And, BTW, if I saw my buddy switching to his Air2 while his primary reg freeflowed, I'd offer him a regulator, too -- No way to know if the original problem was a freeflow or not, but if it is, he's got about 90 seconds before he's out of gas altogether.

Thanks for sharing your learning experience so that others may learn from it.
Although not fun, these are usually the types of dives we learn the most from.

Keep Diving! Dive Safe!

So yea, good info and good read. Thanks

windapp:

I I was more just commenting on how I had planned during practise to share my octo, but instead ended up trying to share my primary. If that is what comes natural to me, I ought to practise it that way, and maybe get a bungeed octo necklass.

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If you have decided that you want to donate your primary, then I do strongly suggest going to a bungeed alternate. The reason I switched from the standard setup for my recreational gear to a long hose primary with a bungeed alternate was reading a story of a woman who drowned when she went OOA and then discovered that her buddy's alternate had come loose and from its moorings and gotten trapped behind him. Standard octos come loose a whole lot, and the second after you have donated your primary to your buddy is not the best time to realize it has happened to you.

Thanks for sharing your experiences with us.

Just a few comments:

• If you are ever in a low-on-air situation, consider sharing air with your buddy before you go completely out-of-air. There are a number of good reasons to do this. By all means initiate your ascent without delay as well. Doing a shared air ascent should be a relatively comfortable, routinely practiced skill.
• I've seen several examples of regs malfunctioning right after servicing/overhaul. Usually, this is the fault of the reg tech. This is why I only overhaul my regs when necessary, i.e., when they show a decrease in performance, and not according to the overly conservative guidelines recommended by reg manufacturers.
• Keep in mind that SPGs are not always very accurate on the low end and can malfunction (needle can stick, gauge "zero" might not correlate with an empty tank). For this reason, I recommend building in some conservatism to your gas-planning, e.g., plan to surface with no less than 300 psi. You should also be testing the full travel of the gauge needle in your pre-dive checks.
• Task-loading can turn routine, "ingrained" actions (such as checking one's remaining gas supply) into things that you completely forget about. Expect it whenever there is something "new" on a dive, e.g., colder water, new site, new buddy, different exposure protection, greater depth, new drysuit, strong current, etc. Make your dive plan more conservative to accommodate increased task-loading.
• If your "instinctual response" is not consistent with your training, then you need more practice. This really isn't an issue of whether a long hose primary + necklaced backup is better/worse than a short primary + octo. It's a matter of practice so that the appropriate response is given in an emergency situation.
• If you haven't read NWGratefulDiver's gas management essay, I highly recommend it.

Have fun and dive safely out there.