Thank you all for discussing this with me.
I am Deco trained, not that it would have made any difference in this situation if anything it made it worse.
bottom line is as soon as i knew we might have a deco obligation on a non deco dive I should have immediately rescued my wife and ended our dive to satisfy or avoid the pending obligation.
Some background.
all the diving in Coz is deep followed by multi levels up. so it is typical for a computer to show deco at depth then clear 1/2 way through the dive.
What made this dive special was the medium loading of the longer compartments, I had not accounted for it in my thinking and was complacent with the shorter stuff burning off a few minutes after leaving depth.
I accept my mistakes, I made a decision for my buddy, not knowing what her computer was saying about her profile and we were outside the yellow band safety.
As an instructor there is a larger issue than the mistakes I made on that dive.
we use tables based on algorithms, we use computers based on the same algorithms, all of these algorithms are based on guesswork and experimental evidence that the guesses are mostly right for most people. there is nothing specific about any table or computer that will keep you personally safe on any one dive.
we teach that if you exceed a limit by 1-4 minutes that you do an 8 minute safety stop, we did over a 20 minute safety stop and still had 5 minutes on one of the computers.
my wifes air consumption was much better than mine that trip because I had a chest cold normally it is the same. I assumed she had much more air than me. had we not had the medium loading and this had been the first or second dive of the day we probably would have been back on the boat with ~500# making the same decisions I made that dive.
I had 3 watches two on one arm all by the same manufacturer there is no good reason for them to be significantly different, yet there was some variation.
it is faith and magic we put into these devices (a table is a device too). we bet our lives on them, we take it as Gospel that if you exceed a limit by this much you do this, and if by that much you do that. only because it has worked in the past most of the time even if not always.
healing with leaches worked for a long time, and if you need a blood thinner it would still work, but we have moved on. when are we going to get computers that actually take into consideration the person actually diving.
I really do appreciate the comments and I have been here too long to care that some of you are willing to call me stupid. I read past that to see if the comments are useful to others. Bash me all you like, I still love to dive and teach safe divers all that they need to know. including the mistakes that can be made.
my wife learned from this experience also she was embarrassed to be sucking O2 at the back of the boat, she hates to be embarrassed and she will not do it again.
The weighting issue was only hers, I gave her some weight and she was fine at 10ft, but we do not usually get our weight set to have empty tanks and do a stop at 10ft. that is in the realm of 2 mistakes/failures.
I believe it may have been possible that we were a little narced but that would be an poor reason and not an excuse for our actions. by the way one of the divers on our boat that had about the same profile mentioned later when we were explaining why we were down there so long, said "oh I never looked at my computer" BANG!!!!
Put that comment in the "strangest things I heard on a dive boat" thread.
I've only seen that a couple of times, before shipping them to the chambers. Ran out both times too.
