New Redundant Air System-Gas Choice

[Professor Nemo]

New Redundant Air System-Gas Choice



Greetings all and I hope you all have had good holidays. I need some advice from the community. I was fortunate enough to be surprised with a redundant air system for Christmas. It is the XS Scuba system and it was purchased with an Al 19 tank. Now I have to decide if I should spend the extra money to get the tank O2 cleaned so that I can fill it with the same EAN mix, (32% is what I dive with if anyone needs that information to help them better answer the question), as my primary tank or just keep air (21%) in it. I do not intend to use this system as anything other than what it is—an emergency device designed to get me to the surface in the event of an out-of-air situation. I have no interest in stage bottles at this time. So, from personal experience, is it necessary/prudent/advisable/unnecessary to ensure that both tanks carry the same mixture of gas or would the switch be ultimately inconsequential given the limited amount of time I would be using it? If this has already been addressed on Scubaboard would someone please direct me to that conversation so I don’t waste anyone’s time unintentionally.

Thanks,

Josh

 

[dumpsterDiver]

save you the trouble, people will argue forever, but air is easier, safer, cheaper and since you will not be spending much time at depth, the nitrogen absorption issue is negligible. Especailly if your shop does not have pre-mixed nitrox, you will probably need to dump the entire tank every time you want it topped off, if you use nitrox in it. Of course, if they have pre-mix you would not have to have the bottle cleaned..

 

[MXGratefulDiver]

You wouldn't have enough time on an AL19 for nitrox to be of any value or benefit. It's an emergency bailout bottle ... save your money and fill it with air. Should you ever need it, NDL is going to be the least of your worries anyway ...

... Bob (Grateful Diver)

 

[RainPilot]

I would top it off after a dive direct from leftover backgas 32% and not bother cleaning but what DD said is also valid.

 

[tbone1004]

what they said, but there should be some shops out there that bank nitrox so you won't have to O2 clean them if you want to put nitrox in there. I think EAN30 is the standard mix in your neck of the woods

 

[rongoodman]

I wouldn't bother with O2 cleaning it. Just use banked Nitrox or air, whichever is handier.

 

[Professor Nemo]

Thanks for the advice, everyone. I appreciate it.

 

[rhwestfall]

from the reasons above, air.....

also, I'd not have an emergency source that could be on a dive that could exceed MOD.....

 

[DiverDownD3]

Not really adding anything here just wanted to add an FYI since you are in Greenville. Olympus down in MHC banks EAN 30. So you wouldn't need it 02 cleaned.

 

[MasterChief D]

I'll also echo what everybody else has suggested (air is fine - the size is such that you can only use it to get to the surface, hence higher O2 % does not add any real value). The only thing I'd add, is that, given its size, I'd always make sure it's filled to working pressure (i.e. top off before the start of the dive, from a full tank, rather than at the end of the dive using left-over gas, the pressure of which will be low and won't be able to completely fill the tank).