I am truly sorry for the loss of Fiona. I did not know her but as a fellow diver and human I too mourn her loss.
I'm not against rebreathers. On the contrary, I think the whole concept is totally rad and cool! Full disclosure, I've never used a rebreather or taken a course for using one. However, I have read up on them extensively. I find the physics, physiology, math and chemistry facinating. I've also spoken one on one with several notable authors of rebreather books and training materials to probe a little more into the subject. I think folks with the skill, intellect and risk tolerance who use rebreathers are a special breed and I applaud them. I ain't one of those people. The three H's scare the bejesus out of me - Hypercapnia; Hypoxia; and less so, but still possible: Hyperoxia. I'll always be a simple open circuit bubble maker. My risk tolerance pegs the bottom of the chart.
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