Quote: (Originally Posted by
Marc T)
Thanks for this interesting and very complete answer.
The initial idea was a more general self questionnemnt about the effect of diluent pollution when using a Rebreather versus on OC ( less diluent used - less pollutant in the loop and in the body)
It could be of course the contrary in case of O2 pollution with a progressive increase pollutant level inside the loop during the dive ( using industrial O2 grade is very common in France when personnal use
)
Marc
If it is pollution from the oxygen supply I suppose another gas we should look at would be Argon rather than carbon monoxide. However as we are taking about a small volumetric amount 5% in a 1 to 1.5l/min metabolic uptake I think the lung tidal volume alone would compensate for even a 5% argon or (diluent) by volume in the bag. In a fully closed circuit oxygen rebreather using passive addition maybe be at increased risk but flushing technique prior to assent should resolve.
Industrial oxygen manufactured by synthetic zeolite PSA or VPSA plants produce around 95% oxygen with say around 5% concentrated of diluent gases the major being Argon. Oxygen for breathing normally is from a liquid fraction plant were the oxygen percentage is >99.9% and the certifiction is better but we have PSA plants for field hospitals, and oxygen generation at 95% in the military working well. 3000 Meters up a mountain in Afganistan was the exception!! Deco using high Argon concentrations is a sure way to get bent but 5% is a pretty small percentage. Iain Middlebrook