GrumpyOldGuy
Contributor
Keep in mind, if you run OOA the air in the tank will "expand" also, not just the air in the lines. (Yeah, we both know "expand" is not really the right word since the tank is rigid 
)
)
Question about a situation
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AfterDark
Contributor
Those are all right on. My alone comment was in the context of this bring the solo
divers site, so I naturally assumed one would be well...solo therefore alone at 50' without air. Been there done that from 70-75 ft and it does take up most of your attention.
MitchFtLaud
Contributor
I'm far from the oldest salt here, or have I logged the most dives. But, I started diving back in the late 80's and although most of my time was spent with US Navy divers, not recreational, we practiced all kinds of skills and using the air in our bladder to assend was one of them. I can't remember anyone getting a lung infection and I've done this dozens of times, perhaps even a hundred.
I agree that in an OOA it is probably best to leave the reg in, hope for a few more breaths and leave the BC alone. Actualy, the positive lift may help you use less air from exertion, and as long as you don't run away, hitting the surface a bit positive isn't a bad thing.
But for those curious, our drills were more set up to use the BC inflator hose to inflate the BC and breath from it, this was back before the days of safe seconds, so if your second stage froze up, it was your best option after buddy breathing. I also, just happend to practice this in my pool a few months back, playing around with a new BC and noticed that I didn't have to remove my mouth from the inflator hose to exhale any more, it seems a vent has been designed in now.
For those who want to try it, it's fairly simple. Inflate to neutral, press exhaust button while taking in a breath (still neutral), release button and exhale (going negative). Add air and go again.
Please don't take this as an endoresment, I'm not prepaired to defend it's practice, it's just what I learned thirty years ago, so take it at face value please.
I agree that in an OOA it is probably best to leave the reg in, hope for a few more breaths and leave the BC alone. Actualy, the positive lift may help you use less air from exertion, and as long as you don't run away, hitting the surface a bit positive isn't a bad thing.
But for those curious, our drills were more set up to use the BC inflator hose to inflate the BC and breath from it, this was back before the days of safe seconds, so if your second stage froze up, it was your best option after buddy breathing. I also, just happend to practice this in my pool a few months back, playing around with a new BC and noticed that I didn't have to remove my mouth from the inflator hose to exhale any more, it seems a vent has been designed in now.
For those who want to try it, it's fairly simple. Inflate to neutral, press exhaust button while taking in a breath (still neutral), release button and exhale (going negative). Add air and go again.
Please don't take this as an endoresment, I'm not prepaired to defend it's practice, it's just what I learned thirty years ago, so take it at face value please.
DevonDiver
N/A
I can't find the link about the bacteria risk inside BCDs, it was posted here on SB.
Perhaps, I am lucky, but I've never dived with a regulator yet that went from full air delivery to zero. There's always some 'fumes' to suck on the way up.
It isn't just air expansion in the hoses that can give you that 'little extra'. The reduction in pressure when you ascend can make air available because you are demanding it at increasinlgly lower pressure/density. The key to OOA survival is making an immediate ascent. That relies on several things:
1) Well trained, instinctive response.
2) Lack of confusion and no need for problem solving.
3) Immediate awareness of buddy location (know where they are before your air goes, so you won't need to calculate if you can reach them or not).
4) Direct, vertical access to the surface.
OR
1) Immediate access to an alternative/redundant air source (buddy or pony). The problem with reliance on a buddy is that they may not be able to provide that immediate access... which could otherwise delay your decision to CESA.
I've read some interesting articles that stem from military training, specifically pilots. I've seen simular theories regarding martial arts training. The only way to guarantee fast/immediate reaction is to have a pre-set and ingrained response to a specific problem. Adding more options and alternatives decreases reaction time, by providing choice and consequently requiring problem solving/decision.
Wherever possible, emergency procedures should be clear-cut and consist of a single response.
Perhaps, I am lucky, but I've never dived with a regulator yet that went from full air delivery to zero. There's always some 'fumes' to suck on the way up.
It isn't just air expansion in the hoses that can give you that 'little extra'. The reduction in pressure when you ascend can make air available because you are demanding it at increasinlgly lower pressure/density. The key to OOA survival is making an immediate ascent. That relies on several things:
1) Well trained, instinctive response.
2) Lack of confusion and no need for problem solving.
3) Immediate awareness of buddy location (know where they are before your air goes, so you won't need to calculate if you can reach them or not).
4) Direct, vertical access to the surface.
OR
1) Immediate access to an alternative/redundant air source (buddy or pony). The problem with reliance on a buddy is that they may not be able to provide that immediate access... which could otherwise delay your decision to CESA.
I've read some interesting articles that stem from military training, specifically pilots. I've seen simular theories regarding martial arts training. The only way to guarantee fast/immediate reaction is to have a pre-set and ingrained response to a specific problem. Adding more options and alternatives decreases reaction time, by providing choice and consequently requiring problem solving/decision.
Wherever possible, emergency procedures should be clear-cut and consist of a single response.
Just a cautionary thought ...
I would be concerned about two things. First, there is always the possibility of fungus or mold growing in the bladder. All bad if spores gain foothold in your lungs. Second, if you had cleaned the bladders, to be sure to rinse completely any soaps or solvents so that you are getting completely clean gas. And of course then which gas ...
I would be concerned about two things. First, there is always the possibility of fungus or mold growing in the bladder. All bad if spores gain foothold in your lungs. Second, if you had cleaned the bladders, to be sure to rinse completely any soaps or solvents so that you are getting completely clean gas. And of course then which gas ...
LeadTurn_SD
Contributor
1+.
Using the expanding air in your BC to get an extra couple breaths during the ascent, or as a "poor man's rebreather" was mentioned and described in passing by my ex-Navy instructor in 1976, but never actually practiced in class.
I would not have it at the top of my bag of tricks when considering OOA scenarios... one reason being I really don't want to practice it.
Anyway, a 50-60' CESA is certainly in "reach" for most divers, but as already mentioned you have to start up immediately. We had to perform a 60' CESA in our basic OW class.... it requires you to go without breathing for about 1 minute, but while not the most comfortable thing ever, is not as bad as it sounds.
Best wishes.
Dsix36
Contributor
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Personally, I don't see all the fuss about a dirty bladder. I dive with trimix on almost all of my dives and will always "suck" the wing dry after the dive. No sense in wasting good helium when I can at least use it to talk like Donald Duck for a moment. The wing needs to be empty for Hotdropping on the wrecks here. I have never have any sign of lung infection and I certainly have never disinfected my wing either.
Just my thoughts. Put as much faith in it as you want, or don't.
Just my thoughts. Put as much faith in it as you want, or don't.
Greetings,
Thanks for bringing up this topic. It's a common one for new divers to talk about. "What do I do when i run out of air?" ..... The first thing you need to do is to ensure that you DO NOT run out of air. Equipment today is pretty rock solid, so that's not an issue. If you are using rental gear then get out of that habit and make the investment. If you are using poor quality gear, consider upgrading.
Next ......... Out of Air = Out of Life The standard 2 Out of Air scenarios have a limited at best result of self rescue. The CESA is a low-on-the poll method, with the B-ESA being the bottom of the poll. Practicing either one could end you up in the hospital if you do it from 50 fsw. It's an ejector seat option. You know it's there but prefer to not have to use it.
What's needed here is good management skills. Good awareness of time/depth/gas supply relationships. Learn how your gear reacts and how you need to respond.
Gas Rules ...... hard and fast
1/3 out
1/3 back
1/3 for reserve (or messing around under the exit point with enough to get up and out)
After more than 6,400 dives I live (truly) by the rule of thirds on every dive. Out of Gas is not an option. I don't care if it's a 20 foot beach dive in the cove i dive in on a regular basis or it's doing dives on the Andrea Doria in 240 fsw. 1/3 is 1/3 is 1/3
If you are overly concerned about running out of air carry a redundant supply (not extension gas) of a pony cylinder with at least 19 cuft of air in it. (19 cuft give you 15 cuft usable = 7 to 30 min of air time in no-stop zones)
Good Luck,
Thanks for bringing up this topic. It's a common one for new divers to talk about. "What do I do when i run out of air?" ..... The first thing you need to do is to ensure that you DO NOT run out of air. Equipment today is pretty rock solid, so that's not an issue. If you are using rental gear then get out of that habit and make the investment. If you are using poor quality gear, consider upgrading.
Next ......... Out of Air = Out of Life The standard 2 Out of Air scenarios have a limited at best result of self rescue. The CESA is a low-on-the poll method, with the B-ESA being the bottom of the poll. Practicing either one could end you up in the hospital if you do it from 50 fsw. It's an ejector seat option. You know it's there but prefer to not have to use it.
What's needed here is good management skills. Good awareness of time/depth/gas supply relationships. Learn how your gear reacts and how you need to respond.
Gas Rules ...... hard and fast
1/3 out
1/3 back
1/3 for reserve (or messing around under the exit point with enough to get up and out)
After more than 6,400 dives I live (truly) by the rule of thirds on every dive. Out of Gas is not an option. I don't care if it's a 20 foot beach dive in the cove i dive in on a regular basis or it's doing dives on the Andrea Doria in 240 fsw. 1/3 is 1/3 is 1/3
If you are overly concerned about running out of air carry a redundant supply (not extension gas) of a pony cylinder with at least 19 cuft of air in it. (19 cuft give you 15 cuft usable = 7 to 30 min of air time in no-stop zones)
Good Luck,
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