CESA over Shared Air Ascent: Which is Best

[ReefHound]

The reason a buddy breathing ascent is considered dangerous is that most people lack competence, and a certain phenomenon that has happened all too many times - diver runs out of air, buddy breathes from 100 ft up to about 15 feet, amid the stress and then the relief that the "crisis" is over, decides "I can make it from here" and does a CESA from there, but with all the other things going through their mind, holds their breath.

Explain to me how a diver that has eased his stress to the point he feels the crisis is over is going to blank out and hold his breath on a CESA from 15 feet but in the immediate panic of being OOA is going to have the presence of mind to not hold his breath on a CESA from 100 feet?

 

[Tigerman]

The reason a buddy breathing ascent is considered dangerous is that most people lack competence, and a certain phenomenon that has happened all too many times - diver runs out of air, buddy breathes from 100 ft up to about 15 feet, amid the stress and then the relief that the "crisis" is over, decides "I can make it from here" and does a CESA from there, but with all the other things going through their mind, holds their breath.

I still dont understand where buddy breathing comes from. The trained way to share air is two people breathing from two second stages from the same tank...
If you can do a buddy breathing from 100 feet to 15 feet and decide to do a CESA from 15 feet youve also seriously missunderstood the "emergency" part..

 

[DeepSeaExplorer]

CESA is the option of last resort since there's no guarantee it will be successful.

 

[Darnold9999]

CESA is the option of last resort since there's no guarantee it will be successful.

From 25' .... seriously?

 

[24940]

From 25' .... seriously?

How deep do you think you need to be to embolize? Where do you draw the line?

What about your buddy? 25' depth 10' vis and he has no clue where you are. Is CESA the best option in that case? For that matter, why is it a BETTER option under ANY situation, except for a complete CF dive.

Lost my buddy
OOA

Yeah, CESA looks pretty good at that point, but I have seriously screwed the pooch to get to that point.

 

[Darnold9999]

How deep do you think you need to be to embolize? Where do you draw the line?

What about your buddy? 25' depth 10' vis and he has no clue where you are. Is CESA the best option in that case? For that matter, why is it a BETTER option under ANY situation, except for a complete CF dive.

Lost my buddy
OOA

Yeah, CESA looks pretty good at that point, but I have seriously screwed the pooch to get to that point.

The response was to "there is no guarantee that it will be successful". If you can't CESA from a max 25' dive and guarantee you can do it successfully (assuming no overhead) what the h e double hockey sticks are you doing diving. There is an extremely small risk that you will embolise even breathing out the whole way, however you have exactly that risk on a normal ascent at 30 feet per minute so no added risk using CESA.

We have figured out that you are invested in CESA as never the best option and, I am invested in making the choice depending on the situation. In the initial situation you set up I will use CESA. (Keeping firmly in mind that I wouldn't be in that situation - I always carry redundant air.)

You want to keep adding conditions to try and make air share the obvious choice then feel free I assure you at some point I will go to my buddy before CESA, not yet though. In the situation you just posed, my mythical "competant buddy", I am sure, will come to the surface looking for me if I disappear heading straight up blowing bubbles. Unless they weren't paying attention, then how competant a buddy were they??? Which is my point. CESA from very shallow - extremely low risk. Relying on a buddy, perhaps higher risk unless you KNOW that your buddy can and will provide air with no fumbling, no issues. Some people know that, I don't.

 

[24940]

The point was that "there is no guarantee that it will be successful". If you can't CESA from a max 25' dive and guarantee you can do it successfully (assuming no overhead) what the h e double hockey sticks are you doing diving.

Since I am confident in doing CESA from over 100', should I ask the same of people who are not comfortable doing it from 90'?

No, the point of this thread and the poll is this: Given the choice under the given scenario, sharing air and conducting a relaxed ascent is better than CESA. I have not read one single reason for concluding anything else. Perhaps I missed it?

 

[DeepSeaExplorer]

From 25' .... seriously?

I wasn't responding to your post directly, just the poll in general.

 

[MauiScubaSteve]

CESA is the option of last resort since there's no guarantee it will be successful.

As taught by PADI;

1. Normal ascent
2. Alternate ascent
3. Controlled emergency ascent
4. Buddy breathing
5. Buoyant emergency ascent

If you read the entire thread you can possibly deduce the reasoning for this order (in PADI's eyes).

No matter the agency, buoyant ascent is the option of last resort. Last resort is when you are going to pass out before reaching an air source (buddy or surface), so you drop your weights and do not vent BC, so your non-breathing body might be resuscitated and sent to the chamber.

Please re-read the section on low on/out of air procedures in what ever OW manual you were trained with.

 

[bfw]

Explain to me how a diver that has eased his stress to the point he feels the crisis is over is going to blank out and hold his breath on a CESA from 15 feet but in the immediate panic of being OOA is going to have the presence of mind to not hold his breath on a CESA from 100 feet?

Relief at the perceived end of a crisis can be a powerful cause of carelessness and loss of mental focus.