Out of air under 20 meter after 30 mintues of 10 to 25 meter drift diving
- Thread starter JerseyBoy
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C'mon, guys, aren't there enough "wows" already?
Will you help the guy out with the incident analysis and the what he should do to get better?
JerseyBoy -- one thought - you "did not check my air for the last 10 minutes", perhaps then it was low enough at the last check you might have ascended to a level above others, where you would use less air.
Will you help the guy out with the incident analysis and the what he should do to get better?
JerseyBoy -- one thought - you "did not check my air for the last 10 minutes", perhaps then it was low enough at the last check you might have ascended to a level above others, where you would use less air.
People may be able to help you come to a conclusion if you would complete your profile.
will try to answer your question for you.
Assuming you did a proper CESA, ascending at about 60 FPM or even a little faster, there should have been no problem. That statement further assumes you were still within no decompression limits. Decompression sickness would be possible but unlikely.
If you did not do a proper CESA and held your breath, you risked a lung overexanpansion injury. You are a PDI Rescue Diver. I assume you still have your book. If you do, go back to it and read the part about the four different lung overexpansion injuries.
The essence of remaining within the no deco limits is that a direct ascent to the surface is possible at any time, so long as you don't exceed the ascent rate programmed into the tables. For the PADI RDP, that ascent rate is 60 fpm. So long as you took a full minute to reach the surface, and exhaled the whole way, the likelihood is that you would have been fine.
I think you learned your lesson about checking your gas -- but there are a couple more lessons here, too. You went to the DM for gas, which implies to me that you either did not have a buddy, did not know where your buddy was, or could not reach him. You just learned why buddy teams need to stay close to one another, even when the viz is good. If your spare gas is on somebody else's back, you need to keep that back where you can reach it!
Second, if I am reading your story correctly, the DM to whom you went for gas ran out on ascent as well. What does that mean? It means that he did not retain enough reserve gas to get two people to the surface from where you were. How much gas it that? There are actually ways to calculate it (HERE is a good article on that), and a prudent diver never empties his tank more than that, because you never know when you might have to help someone else. You are not at fault for not knowing about this, because it is not taught in the recreational curriculum of many agencies. But now you know -- plan your dive; you should know what the maximum depth expected is, and you set aside enough gas to get you and your buddy to the surface from there.
Glad you were okay, and thank you for sharing your experience so that other people can learn from it. It takes a rhino hide to admit error here, sometimes.
I think you learned your lesson about checking your gas -- but there are a couple more lessons here, too. You went to the DM for gas, which implies to me that you either did not have a buddy, did not know where your buddy was, or could not reach him. You just learned why buddy teams need to stay close to one another, even when the viz is good. If your spare gas is on somebody else's back, you need to keep that back where you can reach it!
Second, if I am reading your story correctly, the DM to whom you went for gas ran out on ascent as well. What does that mean? It means that he did not retain enough reserve gas to get two people to the surface from where you were. How much gas it that? There are actually ways to calculate it (HERE is a good article on that), and a prudent diver never empties his tank more than that, because you never know when you might have to help someone else. You are not at fault for not knowing about this, because it is not taught in the recreational curriculum of many agencies. But now you know -- plan your dive; you should know what the maximum depth expected is, and you set aside enough gas to get you and your buddy to the surface from there.
Glad you were okay, and thank you for sharing your experience so that other people can learn from it. It takes a rhino hide to admit error here, sometimes.
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A free ascent of only 20m should be a fairly trivial undertaking for an experienced diver, I am assuming that it was not adequately covered in the training that you received. I do not say this lightly or to impute you abilities, there are two possibilities here, one is that you were taught a bunch of stuff that for whatever reason you fail to remember or somehow your instructor(s) overlooked some rather critical item. For the sake of having a non-flame conversation I will assume the latter to be the case. It is important that you review a complete curriculum outline to determine if there are other such gaps.
Now, as far as a free ascent is concerned: It is a fairly easy undertaking, but the risk of early practice should be minimized by someone who is trained to teach free ascents and who deploys a down line that can be used in case of problems. That likely means that you'd "rent" an instructor for a dive, unless you have a qualified (note I say qualified not certified) mentor type available.
Now, as far as a free ascent is concerned: It is a fairly easy undertaking, but the risk of early practice should be minimized by someone who is trained to teach free ascents and who deploys a down line that can be used in case of problems. That likely means that you'd "rent" an instructor for a dive, unless you have a qualified (note I say qualified not certified) mentor type available.
Mizer67
Registered
Way back in the 80's when I certified the first time, they taught us that in an emergency ascent situation, blow one bigger bubble, then stay below that bubble while you whistle to the surface. Not sure how much science was behind that, but supposedly that kept you less than 60FPM ascent.
If you stayed within NDL's, you should be relatively safe.
If you checked your air 10 minutes prior and then ran out that quick, perhaps you developed an air leak somewhere in your rig?
If you stayed within NDL's, you should be relatively safe.
If you checked your air 10 minutes prior and then ran out that quick, perhaps you developed an air leak somewhere in your rig?
DevonDiver
N/A
ThomasScherrer
Contributor
come on, many do similar things, but rare to admit it, and get smarter this way,
when you admit first of all to your self, you can lean and improve.
to thread starter, dont let them be too hard on you,
I have tried exactly the same, current and harder work load, combined with a bit deeper than normal dives
combined with alot of stuff to see and do, and you forget the most important thing, to check that gauge !
the deeper you go, the more often you must check !
the harder you work, the more often you must check !
those two combined, and you end up checking every minute or so,
this way you also get an erly warning uf the usage rate, and will have good idea when to act in good time.
free accents was practised from 6m at my OW
and from 10m at my AOW course, dont know about rescue, since I did not compleete that one yet. (will do next week)
free accent from 20m is a bit more critical due to DCS, so training and good help could be needed here,
if you know how to do it, and you know for sure you can actually perform it,
then there is nothing big to be affraight of, and less reasons to panic.
OOA mostly happen due to divers ignoring the gauge and unavareness of usage.
OOA rarely happen due to technical defects like: blown o-ring, frosen 1. stage, hose brake, 2. reg jamm
when you admit first of all to your self, you can lean and improve.
to thread starter, dont let them be too hard on you,
I have tried exactly the same, current and harder work load, combined with a bit deeper than normal dives
combined with alot of stuff to see and do, and you forget the most important thing, to check that gauge !
the deeper you go, the more often you must check !
the harder you work, the more often you must check !
those two combined, and you end up checking every minute or so,
this way you also get an erly warning uf the usage rate, and will have good idea when to act in good time.
free accents was practised from 6m at my OW
and from 10m at my AOW course, dont know about rescue, since I did not compleete that one yet. (will do next week)
free accent from 20m is a bit more critical due to DCS, so training and good help could be needed here,
if you know how to do it, and you know for sure you can actually perform it,
then there is nothing big to be affraight of, and less reasons to panic.
OOA mostly happen due to divers ignoring the gauge and unavareness of usage.
OOA rarely happen due to technical defects like: blown o-ring, frosen 1. stage, hose brake, 2. reg jamm
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