Question for the masters - TriMix / Manual CCR

[J-Vo]

what's the standard set up for Side winders ?

Dilout on one side identical bailout on the other.

 

[J-Vo]

@Merida Cave Diver

My buddies and I took the NSS-CDS CCR Cave TRIMIX course a couple years ago. I highly recommend it if you can find a solid instructor.

 

[Merida Cave Diver]

This is all great stuff. Where I am, (I think I mentioned this in earlier posts) the caves generally start at 40m, and other than one I’m aware of, they don’t go deeper than 70. Once I get everything dialed in then I probably won’t change much but yeah my sides will be identical AL-80s.

 

[lermontov]

Dilout on one side identical bailout on the other.

so you mean two identical mixes and no deco gas ?

 

[grantctobin]

This is all great stuff. Where I am, (I think I mentioned this in earlier posts) the caves generally start at 40m, and other than one I’m aware of, they don’t go deeper than 70. Once I get everything dialed in then I probably won’t change much but yeah my sides will be identical AL-80s.

While they’re a pain to source there, once you start penetrating more than a couple (few) hundred meters at 70M, it’s prudent to switch to something like 19L or similar

 

[rjack321]

so you mean two identical mixes and no deco gas ?

the base system for the kiss sidewinder and fathom gemini uses L and R sidemount cylinders wuth the same gas in them - just like if you were OC sidemount.

deco gases, if any, need to be carried elsewhere

 

[J-Vo]

so you mean two identical mixes and no deco gas ?

Deco bailout is carried in additional tanks.

 

[wedivebc]

Bailing to 1.6 is, in general, a very bad idea. Even moreso in a cave.

You'll find all sorts of nonsense like this in the CCR community, often attributed to "well known names" even.
It's up to you to sort out the "that sounds like a bad idea" from the useful.

Please explain why you say that. I am not referring to the cave part because I get it but open water where direct ascent is feasible? Extraordinary claims require extraordinary evidence.

 

[Wibble]

Please explain why you say that. I am not referring to the cave part because I get it but open water where direct ascent is feasible? Extraordinary claims require extraordinary evidence.

A bailout isn’t just for bailout. It’s just as valid for offboard diluent gas where you’re using it should you have problems with your diluent, e.g. flushing down the loop. Also a bailout could be due to a CO2 hit and a lower PPO2 is better. Similarly a very stressed over breathing diver bailing out would be better off with a lower PPO2 – don’t want an OxTox on top of the other grief.

From what I’ve been taught and told, a lower PPO2 for the bottom bailout is preferable to one pushing 1.4 or higher.

 

[wedivebc]

A bailout isn’t just for bailout. It’s just as valid for offboard diluent gas where you’re using it should you have problems with your diluent, e.g. flushing down the loop. Also a bailout could be due to a CO2 hit and a lower PPO2 is better. Similarly a very stressed over breathing diver bailing out would be better off with a lower PPO2 – don’t want an OxTox on top of the other grief.

From what I’ve been taught and told, a lower PPO2 for the bottom bailout is preferable to one pushing 1.4 or higher.

Do you really think the value of the lower PO2 as emergency diluent offsets the benefit of the higher PO2 when bailing out from a deco situation? Firstly if you are in a situation where you are out of diluent you might consider ascending.