Nitrox Question

[DandyDon]

OC-1 is Oceanic right? You got a manual but didn't really study is well huh? Whatever other good computer aids are out there, you must know how your make and model works as they differ.

For Oceanic & Aires: The reasons why probly have more to do with lawyers than safety, but if you set to Nitrox without turning Default off, then you have to reset it for every dive until it resets 24 hours after your last dive. Otherwise it will track 50% O2 for O2 loading but in many models - 21% O2 for N2 loading. You have to understand and control your computer, not just dive it and see what happens. (I think Oceanic computer owners typically turn Default off as soon as possible and never turn it back on but do make sure your FO2 setting is correct for every dive.)

Here is an online copy of your manual, and it is kinda nice to have a copy stored on your computer: http://www.oceanicworldwide.com/pdf/12-2761-r02 Eng.pdf Overview for FO2 Settings and 50% Default starts on page 86.

 

[SeaCobra]

Thanks, I just wrote that down in my log book for reference in the future.

Wasn't the MOD formula part of your nitrox course? In the NAUI nitrox book there is an appendix with all of the formulas listed in one section for easy reference.

Jeff

 

[DandyDon]

Thanks, I just wrote that down in my log book for reference in the future.

Oh your computer does all that for you.

Have you tried the Sim dives? Good practice.

 

[ScubaSteve]

Oh your computer does all that for you.

Have you tried the Sim dives? Good practice.

While that may be true, it is a good practice (and often a required practice) to calculate the MOD for the gas tested BEFORE leaving the dive shop and writing it on the tank. I for one would rather not have to carry my AI computer, regs etc. into the shop just to calculate the MOD when knowing the formulas (that you needed to know to pass the course anyways) will get you there easier.

 

[String]

Please forgive a nitrox newbie question, but am I understanding this right? Did we exceed the nitrox safety levels with the second dive even though both dives did not individually exceed the safe depth levels? We again dove nitrox a few days later at Moorea but had no such problems there. We also weren't as deep.

We need the exact % O2 in the mix, the maximum depth of the dive and what the computer was saying.


It could be a computer fault or more likely as i suspect a user error entering it into the computer. Checking the correct nitrox % is displayed should be part of your predive or buddy check immediately before getting in. A lot of computers will after a set surface time go back to nitrox 21% for safety reasons.

 

[ianr33]

I've had an Aeris (Oceanic) computer for years. Overall it's great but there is one thing I don't like about it. Once submerged there is no way to check what O2% it's set for. Really good idea to double check the O2 setting immediately before descending.

 

[Cave Diver]

I've had an Aeris (Oceanic) computer for years. Overall it's great but there is one thing I don't like about it. Once submerged there is no way to check what O2% it's set for. Really good idea to double check the O2 setting immediately before descending.

Yeah, some of the computers out there have some funky settings. I've only heard about the liquivisions, never actually played with one, but my understanding is that they are customizable to the point that you can actually decide what settings you see on the home screen. Sort of like dragging frequently used icons to your PC desktop. I like the idea of that, if it's accurate.

 

[Jax]

I've had an Aeris (Oceanic) computer for years. Overall it's great but there is one thing I don't like about it. Once submerged there is no way to check what O2% it's set for. Really good idea to double check the O2 setting immediately before descending.

To have a computer reset to some "safe" setting (like 50%) would seem to promote complacency --

For me, I'd rather know that it's up to ME to set my computer, and any failure on my part is just that . . . . not someone who is trying to make a computer think for me.

Fortunately, I can set my Uwatecs to 'expire' nitrox settings in various time periods, or not at all, as is my wont.

 

[ScubaSteve]

For me, I'd rather know that it's up to ME to set my computer, and any failure on my part is just that . . . . not someone who is trying to make a computer think for me.

It IS up to you to set your computer. That is the point. No matter whether it defaults high, low or the same makes no difference because it is not the computer's responsibility to ensure that the information has been entered correctly. If you (the operator) enter it correctly every time then there is no safety issue no matter where it defaults.

 

[Jax]

:w-t-f: