Diving 32% Nitrox with "Air" Algorithms

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Some of the older computers did not have a labeled conservatism setting. Instead they let you set the altitude to "one or two mountains" to add a cushion to NDLs.
Aqualung i300 and i300C have a binary conservative factor option. If set to on, the computer adds 3000 ft to the current elevation, shifting the algorithm "one mountain" to the conservative side.
 
there are respected diving medicine professionals that advocate diving EAN on air tables/settings
They should be struck off!!! and anyone who respects them needs a brain implant

Quite why anyone would go to the expense of nitrox training and computer purchase only to subject them to misuse is beyond me.

If there is a dive incident that results in a subsequent hearing of some sort having mis programmed you computer and effectively given false information, is going to cast doubt on your character and mental capability to say the least.
 
They should be struck off!!! and anyone who respects them needs a brain implant

Quite why anyone would go to the expense of nitrox training and computer purchase only to subject them to misuse is beyond me.

If there is a dive incident that results in a subsequent hearing of some sort having mis programmed you computer and effectively given false information, is going to cast doubt on your character and mental capability to say the least.
When I do three or 4 consecutive dives in a day (all passed 100 feet, often with a little deco here and there), I always set my Fo2 at 1% less than actual.

This is my safety factor and if the chamber operator ever asks me about it, I will tell them I did it to ensure that I was being "safe". I figure they will probably treat me nicer if I can give them a good laugh, right up front.
 
1% is like driving at 29.7 mph in a 30 zone. Setting your computer to air when diving on nitrox is more like the equivalent of causing a traffic jam and the resultant reckless overtaking.
 
Some of the older computers did not have a labeled conservatism setting. Instead they let you set the altitude to "one or two mountains" to add a cushion to NDLs.

Ha, Oceanic computers give you one mountain, 3001-4000 ft.

Aqualung i300 and i300C have a binary conservative factor option. If set to on, the computer adds 3000 ft to the current elevation, shifting the algorithm "one mountain" to the conservative side.
So just curious...... How is lying to your computer about the actual altitude you are diving really much different than lying to your computer about air vs 32%? .......since both lies are intended as false info to create more safety and conservatism. ?
 
So just curious...... How is lying to your computer about the actual altitude you are diving really much different than lying to your computer about air vs 32%? .......since both lies are intended as false info to create more safety and conservatism. ?
Maybe it still knows the correct oxygen exposure? Not that it matters in your scenario, but I am struggling here.
 
Holy-thread-argument! :giggle:

I read through some of this thread, but not all of it. Interestingly I was having this conversation with DAN, in the interests of diving more conservatively, they recommend (as part of other items) diving with two computers running the same algorithm, but one is set to air, whilst the other is set to your actual nitrox mix. That way you can dive within the NDLs of air, but still have the OTU / CNS tracking / MOD warnings for Nitrox, and have an accurate log should there be an issue afterwards.

Personally, I found that just setting your GF-Hi to about 1/3rd less when using EN32, resulted in a similar end SurfaceGF as to what it would have been had you dived on air, with your original GF-Hi settings. I'm sure there are some mathematical calculations to get an exact idea in the background, but since I mostly dive based on the SurfaceGF value, it wasn't really worth more research. I still dive with two computers but mostly just for redundancy, I set them both to the ENX mix I'm diving (usually 32%) and set my GF-Hi to about 45 instead of 70.

Want more conservatism? Try the rebreather, and not only have a mobile nitrox blending machine always ensuring you're on the best mix, but do your safety stop on pure O2 (oxygen flush).
 
Holy-thread-argument! :giggle:

I read through some of this thread, but not all of it. Interestingly I was having this conversation with DAN, in the interests of diving more conservatively, they recommend (as part of other items) diving with two computers running the same algorithm, but one is set to air, whilst the other is set to your actual nitrox mix. That way you can dive within the NDLs of air, but still have the OTU / CNS tracking / MOD warnings for Nitrox, and have an accurate log should there be an issue afterwards.

Personally, I found that just setting your GF-Hi to about 1/3rd less when using EN32, resulted in a similar end SurfaceGF as to what it would have been had you dived on air, with your original GF-Hi settings. I'm sure there are some mathematical calculations to get an exact idea in the background, but since I mostly dive based on the SurfaceGF value, it wasn't really worth more research. I still dive with two computers but mostly just for redundancy, I set them both to the ENX mix I'm diving (usually 32%) and set my GF-Hi to about 45 instead of 70.

Want more conservatism? Try the rebreather, and not only have a mobile nitrox blending machine always ensuring you're on the best mix, but do your safety stop on pure O2 (oxygen flush).
For anyone with a computer that has adjustable GF's, there is no point in using air instead of actual O2. I can see it for computers that have limited conservativness settings, but even then I think there are better ways.
 
https://www.shearwater.com/products/teric/

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