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CO2 cartridge

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Dec 24, 2002
what would happen if you took a CO2 cartridge, filled up a balloon and breathed with it. would that build up your CO2 tolerance?
sounds like a really bad idea

I think that CO2 aproaches toxic levels at a partial pressure of about 1.5 psi (I'll look this up or someone else can post if they know) -- you are talking about jumping to a much higher level all at once. It sounds like this would probably be unpleasant at best, assuming you can clear the C02 from your lungs before your saturated CO2 level gets too high. My guess is that there is a serious risk of injury or death if you cannot expel the C02 quickly enough.

Someone on the site is bound to know the gory details of CO2. Maybe I'll look this up as well.
Did a little research

ok, here's a summary from a little research that I did. If anyone spots some errors, please feel free to correct them. For example, I am not a chemist so when I found references to "%" of a gas, I am unsure whether it is expressed in terms of mass, molar equivalent etc. This will screw up some of the conversions that I use below, but not by a whole lot. At any rate, here's what I think I learned:

- The amount of CO2 in out ambient atmosphere is negligible (about 0.03%)
- The volume of C02 produced is approximately equal to the amount of O2 consume (i.e. each molecule of O2 'lost' is converted to a molecule of CO2).
- During normal breathing, we use about 3 kPA of O2 (i.e. at atmospheric pressure, the air going in is about 21% O2 and the air going out is about 18% O2)
- This means that the air in our lungs, just before exhalation, is normally about 3% CO2 (the ambient CO2 is negligible).

Each % of gas in the composition corresponds pretty closely to 1 kPA partial pressure of that gas at sea level. In other words, "%" of gas and kPA partial pressure for that gas are essentially interchangeable at sea level. At any rate, here's a table of physiological effects:

CO2 kPA* Effect (from http://www.cisatlantic.com/trimix/AQUAcorps/mix/CO2Summary.htm)

Normal (0-4 kPA): May experience mild to moderate dyspnea

High Normal (4-6 kPA): Dyspnea, anxiety (a decent breath-hold will get you to this point -- I sometimes get a flash of paranoia at the end)

High (6-10 kPA): Impaired mental capability (I would be surprised if you could voluntarily hold your breath much beyond this point -- the lowest SAO2 level that I have ever heard of with voluntary apnea was about 40%, which corresponds to 0.6*21% or a CO2 level of about 12% -- i.e. 12 kPA)

Very High (11-15 kPA): Severely mental impairment, discomfort nausea (ok, so some guys can get to the low-end of this range voluntarily, and I think that vigorous anaerobic effort and the accompanying O2 debt can temporarily exceed your ability to ventilate and drive you up in this range)

Super high (16-20 kPA): Loss of consciousness (the likely outcome of zumaz's proposed experiment)

Over the top (> 20 kPA): Uncoordinated twitching and convulsions (another possible outcome of the proposed experiment)
Apart from the enormous risks of breathing 100% CO2, I am not sure if cartridges contain pure CO2. They might contain contaminations etc. cause they are not manufactured to serve for breathing.
Just like there is a difference between industrial oxygen and medical oxygen.
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