Does Nitrox kill brain cells?

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The MOD calculation doesn't change, whether you're calculating for 32% or for 100%.

. . .

My question is how many of you Nitrox divers were taught the formula when you were trained and how many still remember it and use it and why or why not.

Our shop won't let a tank out the door without the diver calibrating the analyzer, analysing the tank, computing the MOD and entering it into the log book, so yes, I still remember how to do it. :cool:

It doesn't matter if it's your 500th tank of 32%, every tank gets individually analysed, logged and signed.

Terry
 
Somewhere in here I'm betting there's an argument for standardized gasses...


Absolutely there is an argument to be made for standardized gasses. However, even a "standard" gas needs to be analyzed to ensure you have what you think you have. You also still need to know how to figure out the MOD for that "standard" gas.
 
It doesn't matter if it's your 500th tank of 32%, every tank gets individually analysed, logged and signed.

Of course, but do you also say to the customer, "I know this is your 500th time on 32%, and I know you have a chart, but you must use the formula to calculate your MOD. And we'll be watching, so don't take any short cuts!"
 
Of course, but do you also say to the customer, "I know this is your 500th time on 32%, and I know you have a chart, but you must use the formula to calculate your MOD. And we'll be watching, so don't take any short cuts!"

No, I can see memorizing 111 FSW & 114 FFW for 32%.

But is everyone dumping the tank before filling? What if you do an air top of 32% or a 32% top on air. For the shops doing partial pressure what if you were a shade off and ended up with 31% or 33%?

Incidentally, the shops down here have started mixing 31% to back off a shade from the 1.4 PO2 max that 32% will give you in Ginnie and Little River because of the recent accidents where divers were within that 1.4 PO2 but still toxed.
 
But is everyone dumping the tank before filling? What if you do an air top of 32% or a 32% top on air. For the shops doing partial pressure what if you were a shade off and ended up with 31% or 33%?

I said this:
For me, I test the mix, set my computer and go diving. If my tank is refilled with Nitrox and I'm not going to dive it right away, I tag the tank to remind me to test it again before I dive it.

I test every fill myself with my own tester. Logging it at the fill station only protects the shop but does nothing for me.
 
I've just done a nitrox course and they taught the formula as well as the underlying concepts. Given the potential problems with going too deep, I made it a point of memorising the formula. I am doing a nitrox dive next weekend and I have planned these dives using the formula, tables and on my comp. They all agree so I'm happy to go ahead with the dive.
 
Of course, but do you also say to the customer, "I know this is your 500th time on 32%, and I know you have a chart, but you must use the formula to calculate your MOD. And we'll be watching, so don't take any short cuts!"

We don't supply a chart, and the diver can use whatever method they see fit for calculating MOD. We're not babysitting anybody, just making sure that the user has personally verified the tank contents.

Terry
 
Incidentally, the shops down here have started mixing 31% to back off a shade from the 1.4 PO2 max that 32% will give you in Ginnie and Little River because of the recent accidents where divers were within that 1.4 PO2 but still toxed.

What incidents were these?


Our shop just makes us analyze, sign off and verify, with a sharpie written piece of tape that shows the mix % and MOD. They have a handy chart on the wall.


We did the math in nitrox class-instructor tried to take my pre-programmed graphing calculator away from me :dork2:

I keep a chart at my desk at work for those mid day brain vacations...it has the formula written on the bottom for when I get really bored.
 
Absolutely there is an argument to be made for standardized gasses. However, even a "standard" gas needs to be analyzed to ensure you have what you think you have. You also still need to know how to figure out the MOD for that "standard" gas.

A gas is only as standardized as the analizer reads when you sniff it.

It is not that hard to be off a few % when mixing and it is still up to the user to varify the true mix.
 
Just finished the SSI Nitrox class this week and we were taught to use the "Equivalent Depths - based on F02" tables (comes with the book in a separate table from the EANx dive tables and has the CNS clock on the back side, starts at 22% and goes up to 36% so kind of useless after that but good for 99% of rec diving stuff.
 
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