What is the deepest you can do an OOA?

[Crazy Fingers]

130ft is about 40m

Using a sensible ascent rate of 10m/min you'd need to be able to hold your breath, begin to swim vertically and maintain that for around 4 minutes. Im sure a very small % of people can do that but i seriously doubt many can maintaining a normal ascent rate therefore reducing the chances of a bend.

Then add in (i) stress of the situation and (ii) the fact you're likely to have less than half full lungs at the time and its something very few people are going to be able to complete safely.

Id be amazed if it can be done safely by most people from even 1/3 of that depth maintaining a sensible ascent rate.

Yeah, but remember that the Navy tables were based on a 99% (or is it 99.9%?) chance of a healthy young man not getting bent at an ascent rate of 60 feet/min. Being that I am not out of shape, young, and healthy, If I go OOA from depth, am really feeling the lung burn, I ain't gonna go 30 ft/min, that's for sure. I'll take my 1% chance of getting bent vs. my 99% of drowning on a 4 minute ascent.

 

[all4scuba05]

It isn't that sh_t never happens to them ... it's that they've considered what might happen, weighed alternatives, and planned for more appropriate responses. Well they failed to plan for the fact that someday their buddy might not be available. I did a 90' wreck dive with an instabuddy. I rely on my pony as backup before relying on a stranger that might not be there if I need him. I specifically mentioned that scenario and all they talk about is that planning and team skills will always get me to the surface. What scenario are they talking about? Because if it's mine then they aren't planning correctly.

CESA is your last option in an emergency ... not your first one.If it was my first one I wouldn't have a pony.

Proper planning and monitoring of your gas supply will keep you from having a gas emergency in all but a tiny fraction of a percent of all the dives you will ever do.That tiny fraction is why I have the pony. I planned that dive with the best Nitrox mix and figured out my time at depth with the amount of air in my tank. I don't have a problem with planning.

Choosing an appropriate dive buddy will eliminate virtually any need for CESA. In the case of having to dive with a buddy of circumstance, alternatives would include either maintaining a conservative (shallow) dive profile or taking an alternate air source. If I were traveling alone in a case like that, I'd probably make arrangements to sling a pony and dive solo ... it'd reduce the risks.On a 90' wreck dive it makes no sense to dive at 50' just because I'm with an instabuddy. I bring my pony. Always have on deeper dives.

In other words, there are way more options than the ones you're allowing for. Either through misrepresentation or ignorance you are ignoring the most viable ones...

... Bob (Grateful Diver)

Are you reading all my posts? Because you're stating things that I should do when I already said I do them. I started this post wanting to know what the deepest CESA was(without getting sick). I don't plan on making it my solution for all emergencies.

 

[all4scuba05]

Please come up with a scenario where a dive resulting in a CESA was not the result of someone screwing up.

Why don't you go ask all those who have done it and see how many you have disrespected. You've been here long to have read the one about the clogged tube on a solo dive. That was from a well respected diver here.

 

[Soggy]

Why don't you go ask all those who have done it and see how many you have disrespected. You've been here long to have read the one about the clogged tube on a solo dive. That was from a well respected diver here.

I don't recall that one. Could you provide a link?

 

[Soggy]

Why don't you go ask all those who have done it and see how many you have disrespected. You've been here long to have read the one about the clogged tube on a solo dive. That was from a well respected diver here.

Do you mean this? If so, please step back a moment and think about why he had to do an emergency ascent. Was it just "because" or did he screw up somewhere? The answer is pretty obvious. I think Bill would even fess up to where he screwed up.

He describes it in more detail here. Please tell me you can see all the bad mistakes that were made.

 

[Footslogger]

At my age now the answer would be "much less" ...but in th early 70's I did an OOA from 125'. Damn near blacked out before I hit the surface but I made it. Lungs and legs were in much better shape back then.

 

[dbulmer]

All4scuba05,

Soggy has not disrespected anyone - what he states is that to get to the point of having to do a CESA you have gone through a sequence of events that could have been nipped in the bud earlier through appropriate action from both the potential casualty and his/her buddy. The ole adage Prevention is better than cure has been advocated by many a diver on Scubaboard and elsewhere. The CESA is an option but as NWG has already pointed out it's the last option for reasons NWG has already stated.

If you have a good buddy who is aware and communicates regularly, risk is reduced - if you dive with instabuddies then you assume more risk as you are dealing with an unknown factor. It does not mean that an instabuddy is automatically unsafe just that it's more risky until you are more aware of the diver's ability.

On a 90foot wreck I won't be diving with an instabuddy - the option not to dive is always there. I say all this not to chide or chastise but to point out that you can often shape the way Murphy might strike in most cases before he gets a chance to kick arse. Think of it as cheating Murphy

 

[captain]

All4scuba05,

Soggy has not disrespected anyone - what he states is that to get to the point of having to do a CESA you have gone through a sequence of events that could have been nipped in the bud earlier through appropriate action from both the potential casualty and his/her buddy. The ole adage Prevention is better than cure has been advocated by many a diver on Scubaboard and elsewhere. The CESA is an option but as NWG has already pointed out it's the last option for reasons NWG has already stated.

If you have a good buddy who is aware and communicates regularly, risk is reduced - if you dive with instabuddies then you assume more risk as you are dealing with an unknown factor. It does not mean that an instabuddy is automatically unsafe just that it's more risky until you are more aware of the diver's ability.

On a 90foot wreck I won't be diving with an instabuddy - the option not to dive is always there. I say all this not to chide or chastise but to point out that you can often shape the way Murphy might strike in most cases before he gets a chance to kick arse. Think of it as cheating Murphy

The only problem with Soggy's mentality is he's human. Sooner or later the screw up that he plans so well for will happen, I hope it doesn't surprise him, he seems to have bought into the widely held view by the safety experts that all accidents are preventable. The flaw in that thinking is the human being.

 

[MXGratefulDiver]

Well they failed to plan for the fact that someday their buddy might not be available. I did a 90' wreck dive with an instabuddy. I rely on my pony as backup before relying on a stranger that might not be there if I need him. I specifically mentioned that scenario and all they talk about is that planning and team skills will always get me to the surface. What scenario are they talking about? Because if it's mine then they aren't planning correctly.

The people you are responding to do not put themselves into the situation you describe. They planned for the problem by choosing not to put themselves in a situation where it could occur. You don't seem to be grasping the concept that many of us would not dive to 90 feet with someone we can't trust.

They wouldn't plan your dive because they wouldn't DO your dive.

That tiny fraction is why I have the pony. I planned that dive with the best Nitrox mix and figured out my time at depth with the amount of air in my tank. I don't have a problem with planning.

My idea of dive planning involves choosing an appropriate dive buddy and being properly prepared for contingencies.

One aspect of dive planning you don't seem to be getting is that if there's anything about the dive that makes you uncomfortable, don't do the dive. Going deep with an insta-buddy is one of those things that would make me uncomfortable.

On a 90' wreck dive it makes no sense to dive at 50' just because I'm with an instabuddy. I bring my pony. Always have on deeper dives.

If you always dive with a pony, then why are you concerned about having to do a CESA?

Are you reading all my posts? Because you're stating things that I should do when I already said I do them.

Well, to be honest about it, you are also stating things that say you don't quite understand what you're asking for. Then you're getting all belligerent with the people who are trying to explain it to you. If you don't want to hear the answers, then don't ask the questions.

I started this post wanting to know what the deepest CESA was(without getting sick). I don't plan on making it my solution for all emergencies.

The answer to that question is that it varies wildly ... and depends on the experience, training, physical condition, and emotional stability of the individual diver. There is no quantifiable response that applies to any but a specific individual.

... Bob (Grateful Diver)

 

[gangrel441]

All4scuba05,

Soggy has not disrespected anyone - what he states is that to get to the point of having to do a CESA you have gone through a sequence of events that could have been nipped in the bud earlier through appropriate action from both the potential casualty and his/her buddy. The ole adage Prevention is better than cure has been advocated by many a diver on Scubaboard and elsewhere. The CESA is an option but as NWG has already pointed out it's the last option for reasons NWG has already stated.

What I am reading from Soggy is that CESA is NOT an option that should be considered, and prevention is a foolproof way to avoid it. This doesn't make CESA a last option. It makes CESA an unpracticed option.

One doesn't need to be a scholar in game theory (though it does help ) to know that you should be aware of all strategies and options, so when the situation arises, you can choose the one best suited to the circumstances. If an O-ring can fail on a dive, they tell me why two can't fail on the same dive? Add to that hose failure, first-stage freezes, diaphragm explosion....it is unlikely that any of these will happen. It is very unlikely that multiple occurrences will happen to the same diver on the same dive. But unlikely doesn't mean impossible. Having an option in the arsenal that does not rely on equipment is useful, even if it is extremely unlikely ever to be used.

I would never want to practice a CESA from deeper than 60. That is not to say that if everything went to crap on a 110 foot dive, that I would just say, "Well, I'm screwed..." and sit on the bottom waiting for my lungs to fill. In such a situation, I would much prefer to know the CESA procedure from 60 and attempt it from 120 than rely on instinct, let panic take over, and bolt for the surface on a held breath at the fastest rate my fins will swim me there.

Just a quick word on some of the responses I have read on a few of the first-hand accounds posted here. For anyone who has missed the subtlety, the guys who have mentioned J-valve failures are talking about dives that happened a LONG time ago, when the only way you had an SPG is if you INVENTED one, and when the J-valve was the only indication you had that you were running low. If it weren't for these folks, we wouldn't even be diving today, let alone with ponies, SPGs, Octos....