I think I read something about the sub having a CO2 scrubber which would mean their bodies wouldn’t feel the lack of oxygen due to what you explained, but I know nothing about this.
This is a good question! Not sure which precise units they had and in what quantity, but given the size of the Titan (no way they can support liquid regenerative system with their size and energy reserve constraints), they would have had canister containing solid CO2 adsorbent with a fan (example).
Without the fan, it’s not going to be very effective since CO2 has to actually pass over the solid. Passive diffusion is not going to move the same volume of CO2 over the solid even if the solid was removed from the housing. Even if they didn’t run out of battery, The solid has a maximum capacity - about 7.5 kg for the unit linked above. Even with reserve capacity, an average human exhales ~0.97 kg of CO2 per day.
O2 to CO2 exchange via respiration is mole for mole (you do lose a little mass in carbon and water just by breathing!). Atmospheric CO2 is 0.041% (410 ppm) and O2 is a hair under 21% and that’s the standard to which life support systems are held. Humans lose consciousness at around 3.7% oxygen, but experience hypercapnia at >6% CO2. (Physiology nerds - I converted from the partial pressures in mmHg to % of 1 atm for comprehension)
So in this hypothetical scenario, hypercapnia would definitely precede loss of consciousness due to anoxia.
I think I read something about the sub having a CO2 scrubber which would mean their bodies wouldn’t feel the lack of oxygen due to what you explained, but I know nothing about this.
This is a good question! Not sure which precise units they had and in what quantity, but given the size of the Titan (no way they can support liquid regenerative system with their size and energy reserve constraints), they would have had canister containing solid CO2 adsorbent with a fan (example).
Without the fan, it’s not going to be very effective since CO2 has to actually pass over the solid. Passive diffusion is not going to move the same volume of CO2 over the solid even if the solid was removed from the housing. Even if they didn’t run out of battery, The solid has a maximum capacity - about 7.5 kg for the unit linked above. Even with reserve capacity, an average human exhales ~0.97 kg of CO2 per day.
O2 to CO2 exchange via respiration is mole for mole (you do lose a little mass in carbon and water just by breathing!). Atmospheric CO2 is 0.041% (410 ppm) and O2 is a hair under 21% and that’s the standard to which life support systems are held. Humans lose consciousness at around 3.7% oxygen, but experience hypercapnia at >6% CO2. (Physiology nerds - I converted from the partial pressures in mmHg to % of 1 atm for comprehension)
So in this hypothetical scenario, hypercapnia would definitely precede loss of consciousness due to anoxia.