[f5ve]

An important fact never explicitly stated in this video is that humans in a contained area will die from CO2 toxicity before lack of oxygen. Many people don't know this or actively believe the opposite.

O2 is ~20% of air, but CO2 is ~.04%. CO2 levels are much more volatile and increase rapidly in sealed spaces with humans.

[eastbound]

And, while atmosphere CO2 is 400-800ppm, while a bedroom goes up to 1800ppm in the morning (keep your doors open, it gives you headaches), submariners work at 3000ppm permanently.

[NBJack]

Consider an air monitor too. I worked in a small enclosed office, and I was surprised at times on how much the co2 levels fluctuated. When it got into 4 digits, I learned to open a window or something to encourage airflow.

[philwelch]

That fact alone (along with the CO2 levels on the ISS) has more or less convinced me that the anxiety people have over indoor CO2 levels is an irrational panic. 3000 ppm is actually on the lower side of submarine levels.

[wahahah]

How do they get the CO2 out of the sub?

[mdekkers]

CO2 scrubbers

https://en.m.wikipedia.org/wiki/Carbon_dioxide_scrubber

[sbierwagen]

(Which dumps the CO2 overboard, which is why the sub needs to constantly replenish the amount of oxygen in the air.)

[CobaltFire]

Specifically (at least in the US) amine treatment using Monoethanolamine:

https://en.m.wikipedia.org/wiki/Amine_gas_treating