More Deco Questions

[Hootis]

I was having a conversation with an intelligent gentleman who is new to rebreathers(and contemplating their use), but not new to extremely deep (500 ffw) high altitude (6200') dives. The conversation revolved around some of the many rebreather options, and the pros and cons of each of the designs. One of the questions he had, I did not have the answer to. The question was what is the effect of "rebreathing" the off-gassed decompression gasses during ascent. I have not thought about this, and began to wonder myself.....what are the effects? Aside from loop flushes, is the inert gas fraction increasing while ascending, as the gasses are off-gassed from the diver? Is this a negligable effect?

[rbdave]

The amount is Negligible and the breather maintains your 02 levels which is important.

Cheers

Dave

[Hootis]

You know...I read that question again, and it was totally moronic. The PPO2 is being measured by the O2 sensors and maintained by the solenoid, and the inert gas being off gassed is the same as the gas in the mix, therefore the PPN2 (or He) is simply dictated by the depth. The volume would increase on ascent (both in the loop and body tissues) hence the bubbles. I must have been tired.