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Well here are some of the replies to The first thinking1
To be Honest some are slightly worrying, at least IMO
(I figured out what this (IMO) meant after a long period of stupidness).
As I have still plenty of air left I would go and and try to bring the
diver up even if I would exceeed my no deco time for some minutes.
Once I had brought him to the surface I would go back and do some 5
minutes of deco.
anon
About the Thinking Question 1. We always have at
least one 'spare' diver ashore or in the boat.
The proper procedure would thus be to surface and
immediately send the rescue diver down to investigate.
If he isn't breathing, I'd go for him...
Pdr Egnell
You pose an interesting problem. Are there other people in the boat? It
seems there should be -- you don't wanna go wreck diving without surface
support, do you? In that case, you ought to go up as fast as is safe, and
send somebody from the boat down to rescue the guy. In any case, I don't
think you should blow deco stops, ascend too fast, or blow any other safety
rules in order to rescue another person. You're more likely to just kill\
yourself, too, with out helping the other guy.
Marina Frants
Michael WalzGo for them - but thats just my opinion -
I would rather have a bend than
leave someone to certain death.
Ian Morrison
Ok so the synics amongst us would say..."It depends who it is...!" :)
What ever ans is given is wrong!
If you leave him there and go up for help they may never find him,
If you go down for him you are putting yourself in danger. Possibly needlessly.
If one goes up and one goes down see ans to previous question...
so I refer you to the first ans... "it depends who it is!"
Cos
Did you know that there were other divers down there in the first
place? that is, if you were on a boat, were there other boats in sight
or other buddy teams from your boat??? If there was no other boat in
sight when you went down, it means that he must have been underwater
much less time than you were, however, you don't know how deep he's been.
(You did say it was a boat dive, but...)
If this was a shore dive did you see others swimming out toward the
same general area or did you see any bubbles on your way out?
Now, assuming that you went under soon after you left the shore (perhaps
because of wave action) you wouldn't have any idea.
100 bar ~ 1500 psi... Rememver that NDL time is not some magic line,
however, doing a reverse profile (even if it's just for a very short
period of time) does increase *your* chance of DCS. Assuming you're
diving with a standard AL 80 (you didn't say what size your tank was,
and without that, the pressure is meaningless), you still have about
40 cu ft (half the tank) left.
With this much air left I would have to say that without hesitation I
would go for the other diver and bring him up with me as long as he's
still breathing (you said he was breathing erratically). If it's
clear he's not breathing I'd have to think a little first, but given
the circumstances, I would probably still go for him. It should not
be a problem to bring him up and have *plenty* of air left for
the small amount of deco you will have built up, even extending it
for safety. If you're on a computer, a slow ascent will most likely
clear your compartments before you ever hit the 15' mark so a 3 minute
saftey stop would be the "standard" precaution and I'd extend it due
to the reverse profile.
As long as he's breathing, I'd do a very controlled ascent attempting
to minimize his risk of embolism and/or DCS and to keep his airway open.
If he stopped breathing, I'd probably drop his weight belt and inflate his
BC
so he would head for the surface and the crew on the boat would find
him. I would not, however, break my deco in this circumstance. It would
most likely take the crew of the boat a few minutes to bring him into the
boat anyway.
I would perform any necessary decompression time and probably extend it
by a few minutes to take care of the reverse profile effect. Now,
deepening the dive to 122 ft (from 100) could have a signifigant impact
on your required deco if you're diving the tables. I don't have my
tables handy, so I can't say off the top of my head what types of times
would be involved here, however, I never dive deep without my computer.
If you end up with a lot of deco time, you can meet your buddy at the
15' stop and have him take the diver to the surface and lower down the
spare tank to you (if required) so you can continue deco. BTW, it's
always a good idea to run over several accident scenarios like this with
your buddy ahead of time so you two will * know * what to do.
The ideal situation would be to have your buddy start ascending so
he does not go into deco, but, keep his *eyes* on you (i.e. within
visible range). That way, if necessary, he could take the other
diver to the surface, alert the boat crew about what happened,
commmence CPR, and activate the appropriate EMS via radio while you
continue your deco.
Are you at increased risk for DCS on this dive - you bet. How much
does it increase your risk. I don't think it would increase my risk
to the point that I would be willing to let someone's life slip away,
however, I am a fairly experienced deep diver and know my limits at
depths well beyond what we're talking about here. If available, I would
most likely breath pure O2 for a while after surfacing just to help
offgas the N2 and perhaps prevent any post-dive DCS from cropping up
later. This means that the O2 rig on board should have multiple
connections available and should be large enough for 2 people to breath
from at least as long as it takes to transfer the patients to an
appropriate EMS facility. A small DAN O2 tank would most likely not
be sufficient for this!!!
-Carl-
Well I think Carl has thought this through the best IMO,
However carl states that, like myself,
I am a fairly experienced deep diver and know my limits at
depths
so I think what I am trying to say is the answer is subject to experience
, don't thing that because I agree with carl,
That YOU SHOULD,
IMO you should stick to your own diving limits, and everybody is right to
the same degree, carl and myself could end up as below.
( No disrespect intended CARL).
It is interesting that no body metioned the subject of monofilament
entrapment, ie drift nets,
You go down to get him and get stuck yourself with 100bar at 37m,
now with decompression.
Whats your buddy going to do now???
That is the next question.
Answers SUBJECT Thinking_quest_1A please.
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To roads diverged in a yellow wood, and I,
I take the one less travelled by, and that makes all the difference.
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