Outside you get to enjoy low-CO2 air of 415ppm. Inside, in an 'insulated' and sealed apartment, CO2 levels will exceed 1000ppm in a few hours, which has negati

Outside you get to enjoy low-CO2 air of 415ppm. Inside, in an 'insulated' and sealed apartment, CO2 levels will exceed 1000ppm in a few hours, which has negative consequences for human cognition and sleep quality. I'd recommend buying a CO2 monitor for your home and keep a window slightly ajar permanently, and at least airing out your house/apartment for a few hours each day. This is another major problem with fossil fuels - with higher atmospheric CO2 levels, it becomes harder to ventilate buildings. We need to bring more external air in to achieve the same effect, which also means higher heating/cooling costs.