Bottom Timer/Wrist Computer Question

[ucfdiver]

Are you saying that you know GUE T1 divers who were not taught ratio deco?

Now whether people want to use it after being taught it is a personal choice. Each person has to make their own personal decisions in how they want to dive and take personal responsibility for their diving. I have to respect your right to do so.

I think what I'm saying is-

"but it's clearly not being taught to all C2/T1 students as the primary means of dive planning."

:blinking:

This was seen during a recent debate over ratio deco or pre-cut tables.

The few GUE C2 divers I know use Ratio Deco on average depth. Not in NFL caves (they're Mexico peeps), but I'm not sure how that matters much.

What would you guys who use ratio deco as the primary means of dive planning be doing for a 150min dive @ 90ft? I bet the dive profiles have more to do with it than geographic region, but admittedly my expsosure to ratio deco has been AG's online course, and divers who were taught it in t1 but don't actually use it to plan dives.

 

[Blackwood]

What would you guys who use ratio deco as the primary means of dive planning be doing for a 150min dive @ 90ft? I bet the dive profiles have more to do with it than geographic region, but admittedly my expsosure to ratio deco has been AG's online course, and divers who were taught it in t1 but don't actually use it to plan dives.

For something that far off the map I'd use Vplanner. Rainer and I are planning a 2 hour dive at 80, and even for that RD is punishingly long.

I'll ask Nick how they run long cave dives.

 

[carrielsal]

I wear +2.5 reading glasses, but I still need readers in my mask to read my Viper Air in gauge mode.

 

[Rainer]

What would you guys who use ratio deco as the primary means of dive planning be doing for a 150min dive @ 90ft? I bet the dive profiles have more to do with it than geographic region, but admittedly my expsosure to ratio deco has been AG's online course, and divers who were taught it in t1 but don't actually use it to plan dives.

You do realize RD does have limits, right? I mean, this is covered in GUE/UTD classes (even AG's online one). For profiles far outside those limits, you're taught to consult software.

 

[Scott L]

And was RD not at least taught in your GUE/UTD classes?

all i've taken is fundamentals. and it wasn't covered.
it was covered in friends' courses. but not as a primary planning tool

It was not covered in my F class (12/09) although if it was I probaly would have not absorbed being half asleep from 12 hour days. :shocked2:

 

[Rainer]

Min deco (RD for recreational profiles) wasn't covered in your GUE-F class? That's rather shocking.

You weren't taught how to use average depth in place of max depth with NDL/MDL tables (and how to adjust this average based on the actual profile)?

If you're not using a computer and you're not using average depth, what are you using? Max depth only? I'd pass...

It was not covered in my F class (12/09) although if it was I probaly would have not absorbed being half asleep from 12 hour days. :shocked2:

 

[ucfdiver]

You do realize RD does have limits, right? I mean, this is covered in GUE/UTD classes (even AG's online one). For profiles far outside those limits, you're taught to consult software.

I asked a question about cave profiles over on UTD's website when I purchased the ratio deco classroom and got an answer from one of the instructors that involved spending half the day on deco and oodles of rock bottom gas, when the common deco algorithms called for <30 minutes. I haven't checked their website in a few weeks however, they probly have added 5-10 more courses by now, maybe one's a ratio deco specialty for caves

But to answer your question, I do realize it has limits. Anyone who's seen how the algorithms work, or a graph of tissue loading over time as modeled by either of the two common algorithms realizes that linear relationships break down rather quickly, thus resulting in ratio deco breaking down. Now, if memory serves me correctly, there are maximum stop times implemented with UTD's version of ratio deco that try to compensate for this. I think ratio deco has it's place. Unfortunately for a lot of the dives I do (about 3-4 a month) they're too far outside the range that ratio deco covers....at least at the level where I understand it. AG did the pit on ratio deco (I think?), but I don't think dives like that are outlined in any course, and I'd be willing to bet were a educated guess based off of years of dives and learning his body.

all i've taken is fundamentals. and it wasn't covered.
it was covered in friends' courses. but not as a primary planning tool

How did fundies handle repetitive diving in your course?

 

[lamont]

Do you have any GUE or UTD training? If so, how to use average depth to generate RD profiles should have been covered. It's limitations and relevant work arounds would have also been covered. Your discussion of pure Buhlmann profiles in this forum is rather frightening as well...

He's discussing Buhlmann dissolved phase gas loading, which is the underpinning of every modern decompression algorithm (VPM/RGBM/etc). Discussion of decompression still starts with Buhlmann loading and nobody who seriously studies decompression science ignores Buhlmann completely.

The position by some that Buhlmann and dissolved phase gas loading have been done away with completely is fairly frightening.

 

[LiteHedded]

How did fundies handle repetitive diving in your course?

ummmm
about that...

 

[limeyx]

My Vyper has been working since 2004. Been through a few other computers, but the Vyper has been rock solid reliable over the years.

Same here. Had it fail with low batt on one dive as I think it had been left on wet.
Battery usage is really low in gauge mode