• dnvtr
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    1 year ago

    Genuine question: if they’re airtight, how do oxygen and CO2 levels remain livable? Spacecraft and submersibles require oxygen supply and CO2 scrubbers to keep occupants alive.

    • baru@lemmy.world
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      1 year ago

      how do oxygen and CO2 levels remain livable?

      The ventilation system was explained.

      • dnvtr
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        1 year ago

        I suppose what trips me up is that my brain sees the concepts of “airtight” and “ventilated” to be in conflict and I am seeking further clarification than what has already been provided.

        • kugel7c@feddit.de
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          1 year ago

          The idea is that air exchange mostly happens through a heat exchanger, so the air leaving the house warms up the air that is entering the house, for this to actually work all other parts of the place need to be airtight, because otherwise your heat escapes.

          • dnvtr
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            1 year ago

            I guess this is just a looser interpretation of “airtight” than what I’ve previously experienced in life. In my experience, “airtight” means “zero exchange of air in or out”, but this setup is a controlled process where the only place air exchange occurs is through the heat exchanger. However, from these descriptions, it’s not the same sort of “airtight” as what I’m accustomed to. Not trying to say that anyone is incorrect, just that it’s different from what’s familiar to me and that’s why I was confused.