Nitrox tables

[Nomaster]

You're response is not annoying at all. I think you're right. I just have a brain fart I have to deal with and get used to this. It is important to know all this. Eventually it will stop looking like Japanese arithmatic to me, some day.

You've got a lot of good advice from Larry and Kraken too, I like both, understanding what the gas laws and the tables say allow me to trust the computer, without the understanding it's all magic; magic can kill.
I haven't looked at Larry's link to his computerized table tutor software yet, just finished reading this thread.
Like Kraken, I like playing with the formulas and the gas laws... but then, I enjoyed studying chemistry for years too.
Some of us are stranger than others, I guess.
I'm going to have to activate my check card one of these days,
it's a real pain not having instant access to things I want now...
it's cheaper though.

Tom

 

[The Kraken]

Pilot,
I've been diving that very same computer over 5 years. I've come to trust it and it's never failed me, but that doesn't mean that it can't.

And, yes, you can set your Data Max up to and including EAN50 (50% O2). I've even gotten in the habit of making an air dive in the Nitrox mode simply by setting my mixture to 21%.

Set your percent O2 in the pre-dive mode and when you select a depth, it will give you your NDL.

 

[pilot fish]

You've got a lot of good advice from Larry and Kraken too, I like both, understanding what the gas laws and the tables say allow me to trust the computer, without the understanding it's all magic; magic can kill.
I haven't looked at Larry's link to his computerized table tutor software yet, just finished reading this thread.
Like Kraken, I like playing with the formulas and the gas laws... but then, I enjoyed studying chemistry for years too.
Some of us are stranger than others, I guess.
I'm going to have to activate my check card one of these days,
it's a real pain not having instant access to things I want now...
it's cheaper though.

Tom

Thanks for your help. I'm not a figures person but I realize I need to have a better understanding of it.

 

[pilot fish]

Pilot,
I've been diving that very same computer over 5 years. I've come to trust it and it's never failed me, but that doesn't mean that it can't.

And, yes, you can set your Data Max up to and including EAN50 (50% O2). I've even gotten in the habit of making an air dive in the Nitrox mode simply by setting my mixture to 21%.

Set your percent O2 in the pre-dive mode and when you select a depth, it will give you your NDL.

Yes, I see that now. I've made one nitrox dive in my AOW cert so I now know how to set my 02 rate and the dive planer will give me my new NDL. You guys have been very helpful. thanks

 

[pilot fish]

I've even gotten in the habit of making an air dive in the Nitrox mode simply by setting my mixture to 21%.]]

huh?

 

[The Kraken]

When you set up the Data Max for Nitrox dives, you have to manually input the O2 percentage for your next dive. I just leave my Data Max in the Nitrox configuration and set the O2 percentage at the 21% default. Remember, natural air is 21% oxygen, 78% nitrogen, and 1% mix of other gasses.

 

[pilot fish]

When you set up the Data Max for Nitrox dives, you have to manually input the O2 percentage for your next dive. I just leave my Data Max in the Nitrox configuration and set the O2 percentage at the 21% default. Remember, natural air is 21% oxygen, 78% nitrogen, and 1% mix of other gasses.

OK, I'm real confused. I set my data max to 32%, lets say, then dive that blend. I then do another dive as an air dive but leave the Data Max set at 32%? How does that help? It only gives you shallower depths in dive planner but longer NDS time? Am I reading you correctly? What is nitrox configuration? Is that the 02 setting higher than 21%? You are making me feel sooooooooooooooooooooooo dumb

 

[scubatoys]

When you set up the Data Max for Nitrox dives, you have to manually input the O2 percentage for your next dive. I just leave my Data Max in the Nitrox configuration and set the O2 percentage at the 21% default. Remember, natural air is 21% oxygen, 78% nitrogen, and 1% mix of other gasses.

And actually, there is a setting in the Set 2 area of the computer, called "FO2 50" which you can toggle on or off. When on, you must set your O2 percentage for each dive after diving nitrox, or else it will default to a 21% for nitrogen loading, but 50% for O2 loading... to try to keep you safe on both sides since you didn't tell the poor computer what the next gas was...

If you toggle this feature off, it will always default to your last dive settings as long as it was recent enought that the computer is still on... So for example, if you know you are always going to get the same mix tank after tank, Set FO2 50 off, and then you can just set it before the first dive of the day, and the settings stay for your repetitive dives.

 

[Nomaster]

OK, I'm real confused. I set my data max to 32%, lets say, then dive that blend. I then do another dive as an air dive but leave the Data Max set at 32%? How does that help? It only gives you shallower depths in dive planner but longer NDS time? Am I reading you correctly? What is nitrox configuration? Is that the 02 setting higher than 21%? You are making me feel sooooooooooooooooooooooo dumb

Now you begin to see why you have to learn the gas laws, the formulas, and how it all applies. Once you understand all of this good stuff, you become master of the computer rather than it being your master. You are on the road to creating a useful tool out of what could have become a dangerous monster.
In most cases, you change your O2 percent to match your dive, in some cases, after you understand what's going on, you may make decisions that change your safety margins, hopefully (usually) to the more conservative side.

Tom

 

[DandyDon]

gulp, yeah, yeah, what he said. I'm wayyyyyyyyyyyyyyyyyyy over my head.

No you're not. You have an instructor, your materials, your compueter, and us. Just don't try to understand everthing in 30mintes.

BTW, some of these guys have the idea that you are new to scuba. I asked a Mod to move this to Basic Scuba forum, but he chose New2Scuba. You said you have 95 dives didn't you? It would help in these discussions if you'd update your Dive Info - see Quick Links above.

You know that your Pleagic/Oceanic computer will adjust for altitude. It would aslo help these discussions if you'd list your location in your Profile - see Quck Links above. I cannot join in this part of the discussion, as I live at 3300 feet.

And how well do you know your computer? Very well, or - :11: do you bluff with the cheat sheet? Once you set it on a Nitrox setting, if Deflaut is on, and you don't reset it for every dive until it powers off, it'll track N2 at 21%O2 but track Ox at 50%O2 and lock up for 24 hours. I turn my Defalut off on my Oceanics, yet - still reset on every dive, unless I'm diving the same mix from a bank tank for days.

And don't forget my invatation to post an Intro, if you'd like. Click the first link in my Sig below, then Post Thread, to do so. :colgate: