Janos

Doing the same drill as Mark I managed to keep my ppO2 up by running minimum loop volume and injecting O2 before the ADV kicked in. The caves were very much at a constant level, so going hypoxic didn't really concern me. And at 8m it would have been hard to go hyperoxic.

When I first got the HUD, [url=http://www.rebreatherworld.com/rebreather-dive-computers-rebreather-electronics/7088-janos-dives-shearwater-electronics-his-kiss.html#post68860](Report HERE for those interested) I dived it without a mask on, and then I stirred up the silt as much as I could and put my head inside the resulting cloud. I could see the HUD fine. I am reasonably confident I would always be able to see the HUD in any diving conditions.

However, it's always useful to experience events such as Mark's as it shakes the confidence and reading about it on Rebreather World is of course the next best thing.

Janos

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