Helium deaths

[webfusion]

co2

mrcHans:
Exactly. You will exhale CO2, but the concentration does not rise. Actually, as you run out of oxygen, it falls.

Is that what CO2 detectors are designed to do -- measure the decrease in the concentration? I have never seen that mentioned in the specifications on these things ---
http://www.ferret.com.au/articles/08/0c011108.asp

 

[MRC_Hans]

Is that what CO2 detectors are designed to do -- measure the decrease in the concentration? I have never seen that mentioned in the specifications on these things ---
http://www.ferret.com.au/articles/08/0c011108.asp

I don't expect so. In most situations, the problem is the opposite, that is, you are breathing in an atmosphere with oxygen in it, so as you use up the oxygen and exhale CO2, the level rises. The helium (and other gasses) situation is special in that you have an atmosphere that is a priori devoid of oxygen, so all the oxygen you have is what is already in your lungs and blood-stream (the latter is a surprisingly high amount, enough to keep you alive, if not conscious, for many minutes). Thus as this store of oxygen is used up, you exhale less and less CO2. Technically, the amount of CO2 outsside you will rise, if you are somewhere with a given amount of gas, but the change will normally be negligible.

Hans

 

[webfusion]

## said in a high squeeky voice ##

OIC. thkx mr chans.