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Discussion Starter #1
Hi

I was reading the other day about an experienced diver that got bent at Chuuk and sadly passed away.

In the accompanying article, it mentioned she and her buddy had been to 42 mtrs for 43 minutes (or was it the other way around?) and I get the impression she missed 11 stops.

BSAC 88's don't cover it and I've tried a few other methods to try and work out their deco schedule, but failed miserably - any answers here?
 

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Platinum Member - I wish...
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Suunto Dive Planner does it with 3:03 total dive time, which would indicate 140 minutes of Deco but not sure what profile thats using.

My Buhlmann table doesn't do 42mtrs for 43mins either
 

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Team peanut butter (rescue diver)
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Putting a 42m dive for 43 mins into ideco, on 30 / 85 (Buhlmann ZHL 16/c) on air gives a total time of 126 mins, i.e. a total of 82mins of stops (at 8 different depths). There are other schedules you could do but there's no way I'd want to be missing that amount of stops!
 

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TTFN
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Depends what gases they used so who knows but ....

42m for 43 minutes on air with no deco gas on 100/100GF Buhlmann ZHL16 (none of which is that sensible but is probably similar to what most Dive Computers gives):
12m 3mins
9m 7mins
6m 51mins
total 106mins

20/30 Trimix and 50% deco gas and 20/80GF Buhlmann ZHL16 gives:
24m 2mins
21m 2mins
18m 1mins
15m 3mins
12m 4mins
9m 6mins
6m 36mins
total 98mins

Or CCR with 18/40 Diluent, 20/80GF and 1.3 setpoint gives:
21m 1min
18m 1min
15m 2min
12m 3min
9m 4min
6m 21min
total 77mins
 

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Team peanut butter (rescue diver)
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On a unit assuming a 20/30 mix that would still give a total in-water time of 73 mins on Buhlmann 30/85 (set point of 1.3). Bear in mind that for this type of diving BSAC 88 tables are completely inappropriate.
 

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I don't really understand what answers you are looking for with this thread?
Are you looking for a deco plan for a dive to 43m?
Or are you looking to analyse an incident without having the benfit of any information to hand?
 

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Cake Monitor
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If you have a curiosity about what her deco schedules would have been, why didn't you just ask about deco schedules specifically, instead of bring this incident into it.

Even if this person's friends had figured out that might be why someone was asking the question, it would have been a lot more sensitive to their feelings than saying it outright.

For me, it's the difference between learning useful lessons and voyeuristic interest.
 

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I read it as the OP simply being curious about a hypothetical run time from a real world incident. Nothing wrong with that IMHO.
If he hadn't given the question context (incident), the dive police would have been on him within 5 posts asking why he wanted to to a dive he was incapable of planning.
 

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Discussion Starter #12
If you have a curiosity about what her deco schedules would have been, why didn't you just ask about deco schedules specifically, instead of bring this incident into it.

Even if this person's friends had figured out that might be why someone was asking the question, it would have been a lot more sensitive to their feelings than saying it outright.

For me, it's the difference between learning useful lessons and voyeuristic interest.
I've never incurred a deco penalty even though I am qualified to. The article sparked my curiosity as to what kind of Deco schedule this kind of dive would produce.

There was no voyeurisitc intent or morbid curiosity. Apologies if this came across.
 

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Cake Monitor
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If he hadn't given the question context (incident), the dive police would have been on him within 5 posts asking why he wanted to to a dive he was incapable of planning.
I've been told that discussions on here about incidents involving the death of a friend can be pretty upsetting, but if there was a good reason for bringing the incident into the query I guess that's fair enough. I'm just glad it's not one of my mates being discussed.
 

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aka Chimp 1 or Mavis...
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As the instigator of that sub-forum (ILADFT), that is the reason for it being there so that others can learn although the discussion of dead individuals is a hard-one to judge. It is made easier if relatives can partake in the discussions as sometimes they want answers too.

However, back to the OP, I think it could have been phrased a little better especially as some of the crucial information such as "backgas" and deco gas mixes play a massive part in the calculation of deco schedules and was missing. Hey ho...we got there in the end though.

Regards
 

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I've been told that discussions on here about incidents involving the death of a friend can be pretty upsetting, but if there was a good reason for bringing the incident into the query I guess that's fair enough. I'm just glad it's not one of my mates being discussed.
It isn't a person being discussed - it is a deco schedule. That is well within the limitation of incident discussion, in my opinion. No-one is criticising the dive, the diver, or speculating on the incident - it is a query on deco, but cased on a real dive. The report of the dive mentioned some specifics of the schedule and that is what is being elaborated on. The fact it was an tragic accident is a sidebar.
 

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I've been told that discussions on here about incidents involving the death of a friend can be pretty upsetting, but if there was a good reason for bringing the incident into the query I guess that's fair enough. I'm just glad it's not one of my mates being discussed.
What do you mean you have been told? Of course it's upsetting!
The point is, the OP didn't question the skills/behaviours/etc. of the unfortunate diver. He asked a question around deco theory from a report he had read.
 
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aka Chimp 1 or Mavis...
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Chill....
 

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