Rebreather "Round Up"

[Chuck_Northrup]

A few years back I was on the Nautilus Explorer for the annual "Pseudo Tech" trip and we conducted a hypoxia experiment. I usually share the results with my RB students to show the importance of monitoring PO2.

We used the same set-up you describe with a couple of differences. We had a PO2 monitor (which the "guinea pig" could not see) and also an oximeter to read the 02 in the bloodstream. A mask ensured the test subject could not "cheat" by breathing through the nose.

The experiment began with about 50% in the loop and within 8 minutes it had been breathed down to 8% when the subject "blacked out". The interesting thing was his blood was still 98% saturated with 02. :o

The subject "felt fine" and was more or less lucid up until the point of passing out. The moral of the story is "ALWAYS KNOW YOUR PO2"

There are some people in the RB circles who advocate not only hypoxia exercises with students but hypercapnia exercises as well. :-\

As far as I know there are no training agencies that endorse this. ;D