RonMicjan

you would normally not get co2 buildup in the loop unless you were breathing incorrectly, the pn2 on the inhale side of the loop is less than ambient air, like about 0ppm (parts per million) until the scrubber begins to break through, then you get little spikes of 1- several hundred as the scrubber nears breakthrough. so CO2 is not inducing narcosis unless you are a co2 retainer.

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