Analyzing An Odd Dive

[soltari675]

I went diving to a large quarry last Saturday. I was with a new group I never met, but had a lot of fun. My buddies were another diver just visiting the area and an experienced diver working on his DM certification. I believe he just has to lead a few dives now to finish. The group also had a couple classes going, OW and AOW. It was over 100 degrees that day, so needless to say, being underwater where below the thermocline was around 58 degrees was a priority.

If anyone has read my posts before I am a pretty confident diver. I don't panic easy. I am very focused on my buoyancy, breathing, etc. I can't get enough of diving. Every chance I get to be in the water I am there. This day was odd for me though.

The first dive was good. The water was very clear and blue. Impressive for a quarry. Vis was easily 30+ feet. The quarry owners have run heavy line between underwater attractions in some places, making it easier to find and see more things during a dive. I found it odd that the other visiting diver often used the line to pull himself along and maintain depth. The DM commented once that he thought it was impressive I never used the ropes and swam next to them on my own. He said I would use less air if I used the line instead of just swam. (my consumption rate based on my computer was averaging 0.78 which I think is ok?) I also found that odd. I thought the idea was not to use other stuff to move alone. But despite this we had a great dive. Saw stuff, came up happy near the dock. All was good.

The second dive is where my problems happened. We did a longer than usual surface swim to where we wanted to descend. Again, it was over 100 and because of the temperature below the thermocline I had a 5mm, hood, and gloves. But we got there and descended. All was good. I was letting cold water into the suit to cool off faster and I was fine. But then we get lost. We're following the soon to be DM and it becomes clear all we are seeing is the bottom of the quarry. No problem. After a while though I start freaking out a bit. No reason. Just a feeling that we needed to be elsewhere. We are at 80 feet, so I decide it is possibly narcosis. I motion to everyone to ascend and see where we are. After 20 minutes, it's clear we have no idea where we are. I saw the same underwater shack three times. We begin a slow ascent, and at 20 feet the feeling hasn't gone away. I am still at the edge of panic. At 15 feet we stop for a safety stop. My brain is telling me to surface. That stopping is a horrible idea. But I focused. Made sure my breathing was normal. Checked my regulator to make sure I have it set to dive so I am getting plenty of air. I think about each piece of equipment and assuring myself that all of it is working fine so I am in no danger, and manage to keep myself hovering at 15 feet and then slowly ascend.

We find ourselves a long ways from the shore and way off from where we intended. The DM isn't comfortable descending again, so it's a loooong surface swim. Again, very hot. We did descend to 15 feet about half way back to make the swim easier, but after 2 minutes, the DM came back up and didn't want to do it again. I was done for the day after that.

The strangest thing to me was the panic. Can't quite figure it out. Even thinking it over I can't think of anything that would have made me panic. Nothing was wrong safety wise. I had plenty of air and gear was working perfect. Any outside opinions?

 

[Bubbletrubble]

What was your underwater work rate when you experienced the panic?
Feeling anxiety at depth can be a symptom of narcosis.
It's also possible that CO2 retention played a factor in inducing your panic-like episode.
FYI, CO2 retention can either amplify narcosis or increase the likelihood of narcosis at shallower depths than usual.

 

[Cave Diver]

Co2 would be my first guess as well.

 

[soltari675]

I was relaxed. We were going at an easy pace. When I felt the panic and ascended to our safety stop depth I focused on my breathing and it was normal. Slow, long breaths, but still felt panicked. Perhaps I was breathing abnormally at 80 feet and didn't realize it? Not done it before, but maybe..

 

[Bubbletrubble]

Make sure that you've ruled out a reg problem.
If the cracking pressure is set too high on the 2nd stage, this could lead to a sense of not being able to get enough breathing gas and CO2 retention.
(Since you haven't mentioned any issues with getting "enough" air, there's a low likelihood of this.)

Lots of different factors can affect diver narcosis.
Were you more tired than usual? (More specifically, did you sleep well the night before?)
Were you properly hydrated? (I'd be willing to bet that you were sweating a great deal on the surface beforehand.)
There have been a few reports that being in cold & dark water, having a hangover, conducting a rapid descent, or beginning the dive with a little anxiety (for whatever reason) predispose a diver to narcosis.

 

[TSandM]

If it had gotten better as you came up, I'd say narcosis. But it didn't.

Cracking pressure on the reg and CO2 retention is a possibility -- I had a friend who started using her brand new regulator, and couldn't figure out why she felt crummy in the water. Turned out the cracking pressure was three times what it should have been; the shop hadn't checked it when they assembled the set for her. But I would think an experienced diver would say to himself, "This reg is breathing like cr*&," before he got CO2 toxic enough to feel panicked.

Is it possible you just got spooked? That getting lost and going around in circles bothered you enough to put out a lot of adrenaline, and it stayed with you until the dive was over? I've had some apprehensive periods during dives, but luckily all of mine have resolved before the dive ended, but I can imagine somebody getting sufficiently spooked to stay that way for a while.

 

[Diver0001]

I'm jumping on the Co2 bandwagon too. Your air consumption during the first dive was about 1.5 or 2x higher than I would expect from a diver who was relaxed and breathing properly..... and that was the dive that went well.

In my experience, divers who are breathing this heavily are also breathing at the "top" of their lungs and holding a lot of dead air in the lungs. That will translate into higher than normal Co2 levels in your body, which would explain the symptoms you had.

My advice to you would be to do two things on the short term:

- make a series so shallow dives, not deeper than 30ft and work on getting your weighting and trim really nailed. You didn't say anything about that, but comfort starts with the gear fitting right and being balanced so give that some attention. When you ahve it nailed try diving REALLY REALLY slowly. Kick and glide and spending much of the time hovering.

- work on your breathing. Slow it down and focus in the start on exhaling completely before inhaling again. During your exhale you may feel the tension in your back and shoulders (or other parts of your body). The exhale is when you "release" that tension and hold that fully relaxed feeling for a few seconds as you inhale again. Working on your breathing like this will help you relax a lot more under water and it will help you slow down your breathing and improve the quality of your breathing in terms of fully exhanging the air in your lungs as you go.

Good luck.

R..

 

[cgvmer]

One good thing is you are willing to think about your dive.

 

[DevonDiver]

The strangest thing to me was the panic. Can't quite figure it out. Even thinking it over I can't think of anything that would have made me panic. Nothing was wrong safety wise. I had plenty of air and gear was working perfect. Any outside opinions?

Panic happens. It's not always narcosis, or CO2.... it can be a culmination of small factors...many of which may have been effecting your psychological comfort zones long before you enter the water.

An argument the night before with your spouse, an expected bill, problems at work, too little sleep... and pretty soon your dive starts to get 'darker'. At that point, the little things bug you... the loose fin strap, the fogging mask, the pace of your buddy.. little niggles that you normally wouldn't notice. You aren't happy with your buoyancy, you feel ungainly, normally simple tasks become an effort. This is your psychological state being degraded. Enough factors and you're soon pushed to a stretching point.... an accident waiting to happen.

You don't need an excuse to feel panic or apprehension... it's just life's little way of reminding you that you aren't superhuman... and that your ability to multi-task and expand your comfort zone is not a given thing.

We all have 'bad dives' occasionally... even on sites we've dove many times before, in conditions we are comfortable in, doing activities that we are trained and experienced at doing.... sometimes it just doesn't feel 'right'...and we can sense that the little panic worm is writhing through our normally calm demeanour.

What matters is that you didn't succumb to the underlying panic/apprehension. An important lesson learnt.

Learn to recognise your psychological boundaries, and accept that they can differ on any given day. Be prepared to abort a dive if you start to feel out-of-control or apprehensive... because on those occasions you might just be one glitch away from losing the plot.

 

[DivemasterDennis]

Or...it could be that you were with unfamiliar divers in an unfamiliar place without reference to doing any one thing in particular. It sounds like this was a new experience for you, and the stress and isolation of it may well have been the only real cause of the panic. You were also deeper than planned, it seems from your narrative. You are gaining experience with each dive, and will continue to do so. Stay active, encounter more situations, and stress declines. It's good to analyze the dive, but then move on.
DivemasterDennis