CESA Training

[Angelo Farina]

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Is it? -- These people aren't freedivers: Kate Winslet Breaks Movie Record For Holding Breath Underwater | HuffPost

The article says that she did train as a freediver for weeks. Which was my original suggestion to the OP: get some serious free diving training. When you will become able to free dive down to 30 m, a CESA from the same depth becomes trivial.
Free diving does not require special physical power: it is mostly what happen in your brains and how well you control emotions, breathing and muscles.
Getting that degree of self-control is very useful also for scuba diving: at my first diving course we were trained for 3 months in free diving before getting our first ARO pure-oxygen CC rebreather. And we got our first twinset with OC air after other 2 months of training about neutral buoyancy, trim control and hand and fin propulsion with the ARO...
So my suggestion is back to free diving. Holding your breath for 3 minutes is feasible for everyone...

 

[Dody]

By sentence:

1. probably not. it sounds like you are choosing between and AGE and DCS...
2. Has little relevance. See 1.
3. You can be comfortable and dead.

If your instructor told you any of this, he's an idiot. I'm not much for calling people out for being stupid on here, there's too much room for error, but this "logic" is just asinine.

You've moved from ignorant to a troll in my opinion. This conversation is foolish.

Science, man. Science. Not empty sentences.
1- Whether you fully inhale or not changes everything. And it is pure logic. The difference between being able to exhale for 30 or 60 seconds and only 10.
2- That’s the difference between having the ability to ascend fast and si king if you are negative.
3- I agree this one is subjective.
4- You are the troll.

 

[Dody]

The science. If you review incident reports you will be hard pressed to find CESA being recorded. I haven’t seen one incident in the last 10 years of BSAC annual reports; bearing in mind at least 1/3 BSAC members were originally trained by an agency that teaches CESA.

@Edward3c. I am sorry but I don’t understand your point. Can you please explain as if I was 6 years old .

 

[Dody]

.

The article says that she did train as a freediver for weeks. Which was my original suggestion to the OP: get some serious free diving training. When you will become able to free dive down to 30 m, a CESA from the same depth becomes trivial.
Free diving does not require special physical power: it is mostly what happen in your brains and how well you control emotions, breathing and muscles.
Getting that degree of self-control is very useful also for scuba diving: at my first diving course we were trained for 3 months in free diving before getting our first ARO pure-oxygen CC rebreather. And we got our first twinset with OC air after other 2 months of training about neutral buoyancy, trim control and hand and fin propulsion with the ARO...
So my suggestion is back to free diving. Holding your breath for 3 minutes is feasible for everyone...

I think that I agree with you. Yesterday, my instructor asked me to do ESA(SSI)/ CESA (PADI) again from 5 meters because I failed last time when I breathed before reaching the surface. Then, I realized that it was due to 2 things. 1) I did not inhale at the beginning. 2) I was negatively buoyant at the beginning. 3) I was stressed.
Once I fixed 1 and 2, CESA from 5 m was a walk in the park. Once I fixed 3, CESA from 15 meters was a walk in the park as I was able to exhale all the way without needing to breath. I did it because I l knew I could.
Now, I do understand that in real life, there might be other variables (for example not being able to take a deep breath at the beginning) but the ability to hold his/ her breath thanks to freediving is in my opinion equivalent to being able to exhale for some time without needing to breath. So it can only be a plus.

 

[Dody]

Unless I missed something, there are three risks in testing a CESA: 1) Hyperinflated lungs if you don't exhale. 2) Being out of breath, unable to continue exhaling, inhaling water and drowning. 3) Ascending to fast.
If I miss something, please let me know.

 

[Angelo Farina]

Unless I missed something, there are three risks in testing a CESA: 1) Hyperinflated lungs if you don't exhale. 2) Being out of breath, unable to continue exhaling, inhaling water and drowning. 3) Ascending to fast.
If I miss something, please let me know.

There are other dangers:
4) hitting the boat or other obstacle while ascending
5) if you are also deploying an SMB, you can get entagled in its line
6) When I have seen divers speeding for the surface "out of control" (which could not really be called a CESA, it is just an Emergency Ascent), I often did see them spitting out their reg, and inhale some water even if the lungs are not empty.

 

[Celt]

Unless I missed something, there are three risks in testing a CESA: 1) Hyperinflated lungs if you don't exhale. 2) Being out of breath, unable to continue exhaling, inhaling water and drowning. 3) Ascending to fast.
If I miss something, please let me know.

Practice and training are always a good thing once you understand it’s like practicing to run across an empty road when in reality you may have to do it at rush hour. Anything that has to be done in a hurry underwater has the potential to go badly wrong. Having time to solve problems underwater takes all the stress out of it. The minute you think “I have to get to the surface “ you’re in trouble.

 

[graham p]

I'm not sure that freediving training is the right suggestion for a CESA situation.
I've done two CESA in my limited diving experience, one on my open water training in 1998, and one when my daughtor was being trained in 2018.
When my daughtor and I did it we were on vacation and had been doing a bunch of freediving and snorkeling that week and on the way up I simply held my breath out of habit until I felt the pressure building up in my lungs, at that point i exhaled and continued up without problems.
I consider myself very lucky that I didn't get hurt that day, and think about that experience every time I dive now.I know not to hold my breath on SCUBA but the habit and instinct of breath holding just subconsciously took over while I was preoccupied with how my daughtor was handling the drill.
I think occasional practice of the CESA might not be a bad thing just to reinforce the need for a constant exhale.
Graham

 

[johndiver999]

The science. If you review incident reports you will be hard pressed to find CESA being recorded. I haven’t seen one incident in the last 10 years of BSAC annual reports; bearing in mind at least 1/3 BSAC members were originally trained by an agency that teaches CESA.

My buddy did one (for real) from 90.. He has never heard of BSAC. He dives with a pony bottle now.

 

[johndiver999]

I believe in teaching my open water divers to think. My program is described here: Open_Water+Nitrox+Drysuit-Thavmas Scuba.pdf

In addtion, as an OOG diver ascends, once the water pressure drops to less than their regs IP, they should be getting some gas.

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A regulator will normally provide an intermediate pressure of around 135 psi above the ambient pressure. That is, as along as the tank pressure is sufficiently high.

When the tank pressure drops below the normal intermediate pressure of around (135 +/- plus ambient) then the second stage will be delivered gas at whatever pressure that happens to be in the tank at that moment. We could generate some specific numbers to demonstrate this, but I doubt that is really needed.

The availability of that gas for the diver to use is simply a function of the difference between the tank pressure and the ambient pressure. As long as there is a positive difference, you can get gas from the regulator when the demand valve is opened. If you doubt this fact, simply take the dust cap off your regulator and suck.. You will get air, slowly of course, because you are sucking a very small vacuum (difference between the air pressure at the first stage inlet and the internal space of the second stage hose).

In other words, the normal IP of the regulator does not really come into play, but rather the pressure in the tank.