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  > The CO2 cognition studies are almost definitely wrong. The military has done numerous studies over the decades with much much higher CO2 levels with none of the reported cognitive results reported more recently.

So dozens of studies by disinterested parties are wrong, yet the studies by a single interested party is right? If you really have good standing for believing this, I would like some more information. I am considering installing such a system.

Thank you.

1. It’s not a single interested party. What I called military studies were by at least 3 completely separate groups. The Navy, the Air Force, and NASA. There have also been studies by the EPA, and “disinterested” academic groups.

2. There aren’t dozens of positive studies. There are a handful by 1 or 2 research groups.

There was a meta analysis in 2020 looking at only the academic literature (so excluding military studies). It found that for every positive result there was at least 1 negative one.

Here’s a good walkthrough of that paper.

https://www.construction-physics.com/p/we-need-more-research...

Thank you, I will read a bit more l.

Hi. It would be interesting to read these military studies could you provide some citations or links?

Are they published in reputable journals?

If you read the comment thread I linked to, you can find links to most of them.

The real kicker for me is how absurdly high the effect is in the recent studies. You should basically see A students failing tests when the teacher closes the window.

You should see huge swings in standardized test scores based on building ventilation.

Companies with good ventilation, should absolutely dominate their markets.

And nuclear submariners operating at 10,000 ppm should basically be non functioning if there is any kind of dose dependent effect (which the studies in question say there is).

Reminder that the military held that 4 hours sleep was plenty for a century, and had data to justify it.

Yeah, I’m usually a very scientific man deferring to studies over personal feelings, but I can literally feel the mental fog clear up by the minute if I open a window on the afternoon in my study/work room after forgetting to do so in the morning.

Hell, if I have a day where I am quasi-forced to spend most of it in musty rooms, I get a guaranteed headache.

There are so many things other than CO2 that can affect your feeling of mental fog. In addition the placebo effect is very very real.

ISS astronauts are routinely living in a 5000ppm environment. If the size of the effects of these studies were real, they’d be noticeable.

The most commonly cited study shows that 1400ppm cuts basic decision making ability by 25% and complex decision making ability by 50%. The study also shows a dose dependent response.

So how are people routinely operating at nearly 5 times that level for weeks at a time with no noticeable decline?

Results this large should by very easy to detect by simply measuring the CO2 levels at multiple SAT test taking sites and comparing scores.

Even without looking, an effect this large is the kind of thing that would jump out at the College Board or any other standardized test creator anytime they’re looking through their data to normalize scores or detect cheating.

Here in The Netherlands for classrooms we have regulations that aim for a classroom to stay below 950ppm CO2. I think almost every high school kid can remember how drowsy a full, poorly ventilated classroom would get.

Like I said I’m usually a scientific man but this is such a basic thing that anyone with any daily life experience would immediately recognize this 4000ppm (or whatever) as wrong.

Humans are also quite sensitive to noticing when a room is “stuffy”, so, yeah.

What's the typical temperature change associated with opening the window?

Stuffiness is mostly a function of humidity.

The problem with these casual discussions about CO2 levels is they don’t control for other factors. Opening a window definitely wakes you up, but is it the cold breeze or the CO2?

I had some more time today, just with a cursory google I could find at least 5 studies that show cognitive decline with rising CO2 (and PM2.5, but that’s another discussion).

So yeah, my gut feeling was right. It’s probably good to not consider one negative study disproving a body of positive studies.

There’s not one negative study, there’s many studies over many years.

Here’s a good walkthrough of a meta study attempting to figure out what’s going on.

https://www.construction-physics.com/p/we-need-more-research...

The human brain is a hell of a drug.

This is why we do randomized, placebo controlled studies.

Saying “you can feel the mental fog clear” is likely a placebo effect.

As said elsewhere, there’s at least 5 studies that prove what I felt.

Studies that go against more rigorous studies done over the past 50 years.

As far as I know the army said (and still says) 4 hours is enough short term in the field not routinely.

If you’re saying they suggested soldiers only need 4 hours of sleep long term, do you have any citations for this? Links to the studies they used to justify it.

Because you can read the studies on CO2 and judge the methodology yourself.

Quite, and given that we are all humans, we should have a fair idea from personal experience.