Who here has done a real life CESA and what was your experience?

[InTheDrink]

Hang on while I compose my reply.

 

[InTheDrink]

First: Let's take a current that has gone from being mild/moderate to being very strong in a matter of seconds. You, like everyone else, is hanging, both hands to the wall, trying to keep your mask on.

Second: Then you have an OOA because of kit failure (let's take a free flow. That's probably the most common although not what happened in my situation)

If you are the person at the back, and having the regulator fail/free flow and the current prevents anyone from approaching you, you are:

a) OOA, through kit failures, not poor planning/gas management
b) not in reach of a buddy thru environmental reasons

Web Monkey - you don't own the ocean. You can minimise risks, to be sure, but don't think that every accident is because people screwed up. That's beneath you.

 

[InTheDrink]

Anyhow, it's all getting off topic.

I'm just happy people have done CESAs from depths that I didn't know was feasible and should I ever need to, which will hopefully be never, will be confident that it can be done (and I'll practise in the meantime). It's important to know. Like everything else, getting tunnel vision in any particular area isn't helpful, so adding an extra escape route to your plan is a good thing. It doesn't mean it's your SOP.

 

[InTheDrink]

Web Monkey, the other thing is:

Merry Christmas.

John

 

[Web Monkey]

First: Let's take a current that has gone from being mild/moderate to being very strong in a matter of seconds. You, like everyone else, is hanging, both hands to the wall, trying to keep your mask on.

Second: Then you have an OOA because of kit failure (let's take a free flow. That's probably the most common although not what happened in my situation)

If you are the person at the back, and having the regulator fail/free flow and the current prevents anyone from approaching you, you are:

a) OOA, through kit failures, not poor planning/gas management
b) not in reach of a buddy thru environmental reasons

Web Monkey - you don't own the ocean. You can minimise risks, to be sure, but don't think that every accident is because people screwed up. That's beneath you.

If you read the "Accidents and Incidents" section on SB, you'll need to look long and hard to find any instances where the problem could not have been prevented by following training, using good judgment and good buddy skills. There are a few and they involve medical problems and bad gas.

Just about all the rest start out with small problems that are ignored, lapses in judgment, buddy separation, ignoring training, diving outside of conditions that the diver was trained for and other preventable causes.

As for your scenario above, unless the dive was planned as a "ripping current while stuck to the wall" dive, I'd say that you shouldn't be hanging on to the wall, you should be drifting with your buddy, in which case OOA is nothing more than an inconvenience for a few seconds while you share air and surface normally.

I'm not DIR or a SCUBA God or anything else impressive sounding. I am however fond of breathing on a regular basis and choose to maintain this habit by closely monitoring my air supply and staying close to my backup air supply (my buddy). If my buddy vanishes, I'm heading up, and he does the same.

My attitude as well as that of the others with a low tolerance for "running out of air" is usually caused by a desire to prevent injury and death and not just some weird personality quirk. There's nothing like a little touch of near (or actual) death to drive home the need to follow training and use good judgment.

Terry

 

[islandwheels]

I appreciate that what you say might be achievable in theory, but in practice, in really, really lovely water with 30m+ visibility, do people really stay so tight? I'm curious because I've never seen that in warm, clear waters. In cold, muddy waters, yes, you are like a hawk on your buddy.

Then there's rapidly changing environmental conditions, which you guys know more about than I, but 5m separation in benign conditions can be safe, but if conditions change all of a sudden (change in channel current in this instance), there's no time to react.

Anyway, I'm not making my point or question clear: my point really is, yes theoretically I could learn to stay so close to my buddy this eventuality could never happen. But this would have a very negative impact on my enjoyment of diving. I don't want to always be THAT close in warm clear water on the off chance conditions might rapidly change. And therefore, I'm keen to understand where the limits of CESA kick in. If I'm at 40m and it's not reasonable to expect to do a CESA from there without repercussions, then I'll stick real close to said buddy for that part of the dive, no matter how warm or clear. But at 10m, it appears that I have every chance of being able to make it out fine if the warm stuff hits the fan.

My question was, where's the line. 10m? 20m? 30m? 40? And the question was answered well, mainly by people's experiences. I think it's always important to remember you're more likely to die driving to the dive site than in it. You can't manage risk out of the contract totally. So you choose where your line is. In warm, clear, tropical water, you will, I believe dive differently than in cold dark water and adapt your practises accordingly, rightly so.

Here's another question, and I'm not being facetious: do DIR divers dive in tropical waters and when they do, on a shallow, easy, simple dive - do they dive DIR/Team???

Maybe to close has a price too. On my cert dive in '82 in 60' off San Clemente off SanDiego, I remember my 'buddy' was to follow and I was to lead, after a little while I looked back for my partner and didn't see him so rose up and did a 360 sweep and he was nowhere in sight. I bolted to retrace our path looking everyway and checking every nook and cranny we had been as fast as I could, shortly after a brief pause something grabbed my leg, I turned and saw my buddy exhausted after chasing to keep up. I guess he was so close originally that I just lost him his bubbles mingling with mine. It's funny now but also now I keep my distance, especially when spearing, but knowing where they are is important.

 

[TSandM]

I appreciate that what you say might be achievable in theory, but in practice, in really, really lovely water with 30m+ visibility, do people really stay so tight?

The answer is yes. I did six days of diving in Cozumel year before last, and I dove as one of a team of three. In clear, sunlit water, and in current, you need to TIGHTEN up the team, not loosen it. If you had watched us from above, as our DM put it, you would have seen three people who were attached by invisible rubber bands -- we might slide out a little from one another, but then we'd rebound back. The worse the current got, the closer we stayed.

A long time ago, on a trip to Maui, I decided to do a personal experiment. You see, my husband was of the mind that, if the viz was good, we could be farther apart. So I let him get about 20 or 25 feet away from me, and at the end of an exhalation, I spat my reg out (since, if you are going to have an interruption in your gas supply, it's most likely to become apparent when you try to inhale.) I swam to Peter, discovering as I did it that I not only had to swim ACROSS, but also UP, since with empty lungs, I was negative. I got to him, got his attention, and asked for his reg. By the time I got it, air hunger was very strong, and I was not a happy camper. I learned a big lesson, which was that that much distance is the absolute MAXIMUM I want to be from my reserve gas.

When I dive with similarly minded and trained people, we simply don't allow that much separation to open up between us.

You can run out of gas through no fault of your own. You can have freeflows in regs that shouldn't; you can have the dip tube on a rental tank plug with debris, as someone did in Cozumel, and posted here on SB. If you have an attentive and skilled buddy, and if you have done your job as part of a team, it will be a non-event. If you habitually dive in settings where that is not possible, you should be carrying some redundant gas. A CESA should always remain the last option, and should be vanishingly unlikely, if you have given appropriate forethought to the dive.

 

[Thalassamania]

If you can show me how someone can follow all the required safety procedures including gas management and buddy skills and still run out of air and require a CESA, I'll admit that I'm wrong.

Terry

You're right. Like you my buddy is within reaching distance at almost all times. There have be situations where we've gotten separated even so, and I guess that was one of the questions:

Complete Story

Excerpt were buddies were separated:

We needed to service some current meters, tide gauges and continuous plankton recorders. The bottom's about 110 feet. It was a great day, visibility was more than 100 feet. There were immense numbers of herring in the area for their late summer spawning. Down we went through the loosely organized school to the tide gauges. It took about ten minutes to dump the data and reset the gauges; the herring cast enough shadow that we needed our dive lights to see what we were doing.

Our tasks done we were getting ready to leave, in the blink of an eye there was a snap from an eerie deep green to pitch black. Mounds of herring pressed closely in on us. I was blind. No gauges, no buddy, not even my light was visible. I raised my light and pointed it straight toward my mask. The beam burst into a million mirrored reflections off the herrings scales. I took a slow deep breath and felt myself life off the bottom and begin to ascend. Carefully I maintained slight positive buoyancy with my lungs. I could not see my gauges. I could not judge my upward progress. My field of vision was filled with the scintillations of my light reflecting off the herring that had closed tightly in upon me.

As fast as the dark had arrived it was gone. My eyes were momentarily dazzled. I exhaled sharply and sank back into the darkness beneath me. Another breath started me up slowly. This time, just as my head broke out of the tightly packed herring school, I exhaled gently and transformed my ascent to a hover. From my chin down and out as far out as I could see, there was a black mass of squirming fish so closely packed that there was little room even for water.

I turned to my left through about three-quarters of a rotation. I could see one of my three comrades coming up out of the herring mass, perhaps twenty feet away. She ascended about ten feet and pitched back to horizontal, leveling out and smoothly neutralizing her buoyancy. A circular shaped motion of her light indicated she was fine, had seen me and inquired as to my status with that unique economy of the underwater "OK." I brought my seemingly detached left hand up out of the darkness and responded with a circle of my light.

Suddenly, she pointed sharply to her left, arm stiff and outstretched. I swiveled my head right, and there is one of the most incredible sights I've ever witnessed. Six Giant Bluefin Tuna move toward us, in formation, they pass between us. Each fish, the size of a dinner table that would seat eight, moving fast, yet without apparent effort.. They glide past, each with a huge left eye that stutters for a tiny moment as it find me for a fraction of a second and then moves on to seek it's normal prey. We watch them almost disappear, circle to the right, and move to the other side of the herring school. They come right back by us and go left to the other side of the seamount.

The black shinny mass beneath us starts to break up, the herring resuming more normal individual distances and expanding their school upward and outward. Once again enveloping me in a darkness that slowly lightens to the deep green we saw at the start of our dive. I swam up to my teammate and joined her hover. We moved to the down line and ascended to our deep stop. Being out of the lee of the seamount now the current was rather stiff, we tied off our Jon lines, waited a minute and then ascended to our 20 foot stop.

Decompression complete we signaled the Zodiac, the Coxswain waived us off as he was already heading to pick up our other two comrades at an alternate surface float. Once we were in the Zodiac everyone was talking excitedly about the Tuna, there had been a big school of them working the herring and every one of us had been blessed with a good long view of at least several.

 

[InTheDrink]

Thanks Thal: that's the point I was trying to allude to, maybe ineffectively.

Separation is always possible. You need a backup plan. I'm just trying to work out how much of a backup plan a CESA actually is among other backup plans. That's all.

However, my questions have been extremely well answered, initially by people relating their experiences of CESA, in multiple environments, from training to 'real life', from 'no problemo' to a thirty year gap from diving as a consequence. Very valuable.

Secondly, subsidiary questions, such as why you should never need to do a CESA in the first place, have been well responded to. I hate to press the point, but I am still learning and think it would be arrogant to think that I know better than others with much more experience. One day I'll not need to qualify my statements or posts with that. Clearly there are good grounds to consider separation, in all but the worst or most unexpected circumstances, negligent (and all the consequences that come with that).

I particularly like the drill of spitting your reg and seeing just how far not very far is. I guess that gives a good approximation of what separation really means. Divergent conversation but very useful nonetheless.

As always, the input from you people is invaluable. I'll still look at CESA as an option but that doesn't change my renewed view of separation as avoidable in most (but not all) circumstances.

I still hate absolutes though. That part will never change. Surety being the realm of the fool and all that.

Thx,
J

p.s. and yes, I see the inherent contradiction in hating absolutes absolutely. This is not the SB philosophy forum

 

[Web Monkey]

Thanks Thal: that's the point I was trying to allude to, maybe ineffectively.

Separation is always possible. You need a backup plan. I'm just trying to work out how much of a backup plan a CESA actually is among other backup plans. That's all.

Thal was separated from his buddy (very cool story BTW) for a little while, but Thal did not run out of air and did not require a CESA.

CESAs are taught and practiced as an alternative to death. They're pretty safe when done properly with little nitrogen loading. They get progressively more dangerous as you absorb more nitrogen.

In any case, I've grown tired of trying to explain how an emergency procedure can be avoided by not having an emergency.

Terry