Different mixes and SM

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DaleC

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Not looking for a debate about appropriate mixes, training etc... just a general question for SM divers. Is it a common (or acceptable) practice to use two different mixes in your bottles? For example: two nitrox mixes for varying depths or a trimix/air combo for dives that have a short deep component?
For the appropriate dives would a SM diver use different mixes or keep the side bottles the same and just sling additional stages?
 
Are you serious? Take a "deep mix" in one bottle and shallow mix in the other?

A- If one reg fails, you have ZERO redundancy.
B- Your tanks would be uneven.

I hope this isn't a serious question...
 
Got to switch tanks ever couple hundred psi, two different mixes would preclude you from doing that in your scenario. Also like james said, no redundancy at all.
 
It's just a question.
I don't know enough about the history of sidemounting so I thought I'd ask (if for no other reason than to understand the failure points).
 
Thanks for humouring me :dork:
I usually just think of configurations as systems to be manipulated and in this case did not consider the context that SM is usually used in. I can see how such a thing wouldn't work in cave diving where one does frequent reg switches and there is not a direct bailout route available.

Oh well, the only stupid question and all that...
 
Got to switch tanks ever couple hundred psi, two different mixes would preclude you from doing that in your scenario. Also like james said, no redundancy at all.

Most people don't switch regs that often.


I have had slightly different hypoxic trimix blends in my bottles and did plan on doing the switches so my leaner O2/heavier He would be used at the deepest portion of the dives, but both mixes were within MOD & END of the dive. The O2 was only off by 1% and the He was off by about 3 or 4 IIRC. The O2 was enough to make a difference on that dive. Using different mixes intentionally does eliminate the redundancy of independent tanks.
 
Most people don't switch regs that often.


I have had slightly different hypoxic trimix blends in my bottles and did plan on doing the switches so my leaner O2/heavier He would be used at the deepest portion of the dives, but both mixes were within MOD & END of the dive. The O2 was only off by 1% and the He was off by about 3 or 4 IIRC. The O2 was enough to make a difference on that dive. Using different mixes intentionally does eliminate the redundancy of independent tanks.

I didn't mean that literally, just that people switch every so often at a set pressure from tank to tank
 
https://www.shearwater.com/products/peregrine/

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