15 liters per minute ensures CO2 won't build up during inert gas method?

[Rose57]

I've read the PPH and the mega thread on the inert gas method. The nitrogen gas method seems pretty simple. Is anything else required to ensure CO2 doesn't build up or is setting the regulator to release 15 liters per minute all that is needed?

 

[profoundexperience]

An average human respiration is ~0.5 liters and ~10 respirations per minute ~= 5 liters.

Remember also that air is already ~79% nitrogen, and only a portion of oxygen gets converted to CO2 (that's why mouth-to-mouth works).

Finally, with a smallish bag, "squeezing" all the air out of the bag before starting, "strongly exhaling" just before, and optionally hyperventilating (as recommended in the PPH)...

... CO2 should be extremely minimized and 15 lpm (from the top of the hood/bag) should be totally sufficient to purge any residual CO2.

Somewhere (I think in the PPH) they do a study and make a graph comparing 15 lpm to 5 lpm to "prove" 15 lpm is ~optimal. Have you seen that graph?

Best of luck!

 

[AutoTap]

Yep the above answer, that sounds correct iirc. I wish best luck.