Diving 32% Nitrox with "Air" Algorithms

[inquis]

Works if you have an ancient, air-only computer. These days, just program whatever conservatism makes you happy without lying to the computer. That makes for a consistent margin if you happen to change your mix.

 

[Centrals]

None of my three different brands of dc have safety factor to play around.

 

[L13]

None of my three different brands of dc have safety factor to play around.

Any dive computer can be used with a safety factor. They all display NDL. Just limit yourself to an NDL limit greater than 0 minutes, and you have changed your safety factor.

 

[Bob DBF]

In the interest of adding "conservatism" to our diving, my wife and I when diving the tropics (mostly shore diving on Bonaire ) dive 32% Nitrox. But to increase safety, we still keep our computers set to Air. We fully understand and adhere to the 111ft MOD for 32% and we even augment that by agreeing to stay inside of 100ft max depth as a rule. We just keep our computers set to AIR to add in some more "conservatism" . We then plan and dive the AIR algorithms ....... and NEVER go below the MOD for 32% Nitrox.

Anyone else do this........or does anyone have a reason why not to do this?

No, I see no upside to having my computer lie to me. When I want to dive more conservatively, I use the information the computer gives me and modify my behavior to reduce my risk.

The problem that may come up is that you see a whale shark below you and want to get some pictures, you are at make-believe NDL and know you can violate that. The moment you start down you have no idea of your risk, and you will be in deco as far as the boat op is concerned. You could ask for copies of the pictures everyone else took.

back in the day, when nitrox computers weren't as available as they are now lots of folks dove nitrox while using air computers. I've done it.

One of my buddys still dives the "Brick".

 

[lexvil]

Youll be ok

 

[azstinger11]

Set it right, then don’t ride the NDL.

 

[rx7diver]

As mentioned above, make sure you keep track of your oxygen exposure if you are diving several dives per day over consecutive days. Easy enough to do using NOAA oxygen exposure tables.

rx7diver

 

[lostsheep]

Are all of your clocks set 10 minutes fast so that you’re not late?

 

[Centrals]

Any dive computer can be used with a safety factor. They all display NDL. Just limit yourself to an NDL limit greater than 0 minutes, and you have changed your safety factor.

It is safety practice not safety factor ie. dive conservatively.
What is the point for dc came in with GF or whatnot? I am glad I did not waste any money on those.

 

[johndiver999]

LOL, it might make sense to set one for 32 and the other air. If something weird happens, you sorta have the data that might be useful.

I had a very young buddy and we were doing something similar to described above. We accidentally exceeded the no deco limit (for air) but I was relieved to see my computer showed a good bit of more time. We started the ascent and cleared the deco on the air computer, but it was somewhat of a relief to kinda know the stop was PROBABLY more of a safety stop. Might have some value if you are diving very close together and getting comparable depth profiles.

Overall I think it probably makes sense to just punch in the right mix, have reasonable data for emergencies and just start the ascent when you have a NoDeco margin that you are comfortable with.