Previously I had thought the maximum concentration of CO2 for human health to be given by the ‘Pettenkofer CO2 level’ with a maximum of 1000 ppm.
But according to this post
a growing body of research suggests CO2 levels as low as 1,000 ppm could cause health problems, even if exposure only lasts for a few hours.
Therefore it looks like a lower value than 1000 ppm would be healthier for the human body. Is that so?
What would be the target CO2 level inside a passive house? Since outside it is in the range 3-400 ppm. So with more ventillation we could get closer to 3-400ppm, which is Nature’s default (which shouldn’t be bad?)
Perhaps 750 ppm would be ideal — is there any research on that, either cognitive or related to blood vessels.