Quote: (Originally Posted by
Drmike)
On some deep and/or long rebreather dives the limiting factor can quite often be the amount of bail out gas a diver can physically carry below the deepest/furthest staged gas point.
Optimising the tanks one carries to ensure max gas volume of breathable gas available to the diver at depth has to be balanced against the potential to overburden the diver with too many tanks making access to gear more difficult and creating more drag and too large a profile. Obviously if you have to carry tanks you want to make sure they all are, if possible, breathable at depth.
The process of optimising/minimising the gas (number of tanks) one carries can lead to such things as running wing inflation off one of the bottom bail tanks (instead of carrying another separate air (not breathable at depth) tank for wing. This however still leaves the issue of suit inflation. Obviously its not possible to run suit inflation of trimix also so this has got me thinking about running the suit off the off-board O2 tank.
(Often offboard O2 is needed on long/deep cave dives to supplement on board O2supply and provide redundancy)
Has anyone much experience using O2 for suit inflation?
If its possible then the diver would carry all bottom trimix bail tanks (one being plugged in as off-board dil for the same reason as the need for off board O2) and one offboard O2 tank.
Anyone know of any potential issues? Has there been any research done on this?
Dr Mike,
This was the subject of a discussion recently and one member of the group brought up the issue of potential skin bends. Skin is by definition resident in one or more of the tissue compartments. The salient question is whether skin resides in a tissue compartment that can be supersaturated and therafter off-gass at a rate that matches the rest of your profile.
I have not seen any studies on the impacts of suit inflation gas on overall decompression - would be a really interesting project for a thesis...
oh well ... just my 2c worth.
Dive safe
Nick