Poe Lim wrote:

A lot of things that indicate that we're in line on this topic.

> The mag I was referring to is the April 2001 issue of Dive (appear to be
the
> BSAC's mag). They were going to Chuuk Lagoom, with no close by
recompression
> chamber, so they devised a table based on the Australian Short Oxygen
table
> (RAN 82). Starts at 9m, run time of between 2hrs 6mins and 3 hrs 6mins.
Kit
> consisted of an AGA full face mask, several O2 cylinders, a gas switching
> block (Sarteck), a shot line with D-rings at prescribed depths and a
> commercial diving harness to suspend the diver and attaching the O2
> cylinder. One problem they had to consider was thermal protection for the
> diver, as it's a long time to be in the water. Take a look at the issue of
> you can find it.

I'll Look for it.  I've done a fair amount of research on this.  Here are
the only two links I still have in my favorites list.  I printed out things
I found most interesting as I went, so this is the best I can do on short
notice.  If you are interested enough, I can scan and send additional
information privately, but I expect you can find as much or more than I have
on line and be more certain that you're getting the latest information.
http://www.mtsinai.org/pulmonary/books/scuba/contents.htm
http://www.abysmal.com/pages/articles/inwater_recompression.html

Your description of the program is interesting.  I don't remember seeing
anything on a diving harness.  I like that idea.  On the other hand, it
sounds like, in the plan you describe, the O2 is under water with the diver.
I doubt that would be my choice.  I'd be more likely to go with surface
supplied where the bulky amount of of O2 required could be managed better.
Something you didn't mention that is clear in all of the reading I did, is
that the victim needs to be monitored.  Pure O2 at 9 meters is a CNS
toxicity risk.  This means that you have to deal with thermal protection and
gas for at least two divers, presumably only one of whom is in O2.

> I guess the choice you'll have to make is which would cause less harm;
> putting someone on O2, and getting them to a chamber pronto (assuming
there
> is a chamber whithin 1-2 hours), or trying the recompression, with its
> attendant risks.

That's not a choice I have to make.  This is my own boat we're talking about
and I live in a diver's state in a country that has Coast Guard air and sea
evacuation facilities available.  In other words, the choice is already
made.  Here's my plan.  You and others are free to advise differently
provided the advise comes with some supporting reasons for differences.
Keep in mind that the norm for my boat is to have only two divers, one of
whom is me.  I occasionally have 4 but never more that.  I am the only one
aboard I can be sure has the ability to operate the boat safely (my wife can
drive it in an emergency) and the only one on board I can be sure has any
first aid training or lifesaving training.  I'm a Boy Scout (Eagle Scout in
fact) and Red Cross first aid trained and a former Red Cross Water Safety
Instructor.  On the other hand, my wife is a former Red Cross Senior
Lifesaver (lifeguard qualified in some jurisdictions) one of my dive buddies
is a firefighter and former paramedic and another is a police officer, PADI
instructor and police dive team leader.  Most of the dives done from my boat
are what I refer to as "dead boat" dives.  By this, I mean that there is no
body aboard the boat while we are diving.  We don't do particularly deep,
high current or planned deco dives from a dead boat.  There is one or more
chambers in each or the 4 counties I normally dive in (roughly 30 miles
apart).

Scenario 1 - Victim missed a deco stop, is still conscious with no symptoms.
Solution:  Diving is done for the day.  The oxygen's there.  He/she breathes
it and is loosely monitored while I retreive the anchor and head for shore.
Once on shore, options are considered.

Scenario 2 - Victim has DCS symptoms, is still conscious.  Solution: Diving
is done for the day.  the oxygen is there, he/she breathes it and is
monitored continuously.  Coast Guard is called for assistance and evacuation
to the nearest hyperbaric facility.

Scenario 3 - Victim is believed to be a DCS victim and is not conscious.
Solution: Same as above except monitoring is more intense.  This is the
situation that will cause me to use a quick disconnect on the O2 regulator
to allow me to swap the demand second stage for a demand mask or a constant
flow mask.  In fact, the odds are high that, when I have one, I will leave a
demand mask attached to the system.  It's just as useful for a conscious
diver and is one more obvious difference between my O2 tank and the the
scuba tanks available for use on the boat.

Keep in mind that all of this started not because the risk of accident
increased but because the options for dealing with an accident did.
Previously, I had the same choices for calling in assistance but no ability
to deliver O2 immediately.

> And also the issue of liability . . .

Not an issue in this case.  For starters, I'm a private citizen, operating a
private boat for private purposes.  There's absolutely nothing commercial
involved.  I am insured for liability.  I'm also protected by a "Good
Samaritan" law that protects me from liability for assisting to the best of
my ability.  I do have a slighly increased risk because my former WSI and
Lifeguard experience carry a higher knowledge expectation.  None of this,
however, is an issue for me.  I have only one rule in this respect, if
action by me can save a life or protect someone from permanent injury, I'm
going to act.  If that exposes me to liability, so be it.  Knowing for
certain that I have saved half a dozen lives (in and out of the water) or
more without even a hint that anyone considered suing me gives me some
confidence that I'm on the right track.  Each person picks his/her own
risks.  This is one I freely and knowingly accept.

Lee