Re: Aquatic Plants Digest V1 #192

Hoa wrote:

>Does anyone know how much volume the 5lbs of CO2 will occupy at atmospheric
>pressure?  I wonder if the scenerio above happened while the windows were
>closed, would it suffocate people in a small house or apartment?

The volume of the gas in the container can be calculated if you multiply the
volume of the container with the pressure of the gas in the container (in bars)
(1 bar = 14.5 lbs/in2). My regulator doesn't have a high pressure gauge unfortunately, so I don't know for sure what's the pressure inside the smaller bottles, but the ones here in our lab are filled with about 60-70 bars. If the volume of the container is, say 2.5 liters, that will make 175 liters of CO2.
Let's assume a small room with a floor area of 10 square meters (107 sqare feet). The rooms are usually about 2.5 meters high, so this room will have a volume of 25,000 liters. If you add 175 liters of CO2 to that room, there will be a CO2 concentration of 0.7 percent. No problem.

Even at higher CO2 concentrations, there wouldn't be a problem, as CO2 stimulates the respiratory drive very much. You would feel very much 'out of breath' and open a window or leave the room. CO2 concentrations of 5 to 7 percent are already almost intolerable without being actually dangerous at all (there's still plenty of oxygen).

CO2 is not to be confused with carbon monoxide (CO) which is a very dangerous gas, as it occupies the oxygen binding sites of the hemoglobin in red blood cells (100 times more tightly than O2) and can kill you very quickly.


|                       |                                 |
|Michael Irlbeck        |  u7211aa at sunmail_lrz-muenchen.de|
|Dept. of Physiology    |  mik at physiol_med.uni-muenchen.de|
|University of Munich   |                  CIS:100277,343 |