The US Navy's submarines are run with CO2 levels varying from 300-11,300ppm.[1] The military did plenty of studies in the 60s and 70s and failed to find significant cognitive effects in environments as high as 4% CO2.[2]
> Thus, CO2 at 40,000 ppm for 2 weeks did not affect performance on multiple tests of cognitive function in physically fit young airmen, a population probably not unlike submariners.
> A number of studies suggest that CO2 exposures in the range of 15,000-40,000 ppm do not impair neurobehavioral performance. Schaefer (1961) reported that 23 crewmen exposed to CO2 at 15,000 ppm for 42 days in a submarine showed no psychomotor testing effects but showed moderate increases in anxiety, apathy, uncooperativeness, desire to leave, and sexual desire.
> In a 5-day exposure of seven subjects at a CO2 concentration of 30,000 ppm, Glatte et al. (1967) reported no effects on hand steadiness, vigilance, auditory monitoring, memory, or arithmetic and problem solving performance.
> CO2 exposure did not affect performance on the tracking task or any of the six RPM subtests (Storm and Giannetta 1974).
There's also an argument from biology. When sitting around, people exhale 4-5% CO2. That's 40,000-50,000ppm. An extra 2,000ppm is far less than the variance across a typical breath, and it won't increase ppCO2 in the blood stream nearly as much as standing up and walking around. If CO2 hurt cognition as badly as these studies claim, then even minor physical exertion should turn people into drooling idiots.
It's for these reasons that I am extremely skeptical of the recent claims about CO2 impairing cognition.
Maybe I'm missing it but it seems like most of the studies I click on there see an effect at CO2 levels that are much less than tens of thousands ppm.
Gwern has this to say about the Navy studies-
"they often were not using sensitive tests of higher cognitive functioning, a broad array of different measurements, and very small sample sizes; I suspect a meta-analysis grouping tasks by domain with some correction for ceiling effects might turn in a very different conclusion than their fairly sanguine conclusion that there are no cognitive impairments <40000PPM and <25000PPM is a perfectly safe limit. (Oddly enough, I came across this book on an anti-global-warming site; apparently Satish et al 2012 is really just global warming propaganda scare tactics, because the Navy has proven that CO2 is perfectly safe.)"
I mean the Navy has a very vested interest in saying "submarine CO2 levels are fine" which makes me suspicious from the outset. If other studies corroborated their claims I'd find it more believable.
If what you say is true then there is an almost unprecedented level of being wrong and conspiracy in the current accepted rules and limits for CO2 in indoor air quality. Not to mention the fact that Wikipedia is dead wrong. That seems unlikely.
"The National Institute for Occupational Safety and Health (NIOSH) considers that indoor air concentrations of carbon dioxide that exceed 1,000 ppm are a marker suggesting inadequate ventilation."
It would be quite bizarre for NIOSH, a division of the CDC to be 15-40x off on how much CO2 is acceptable indoors. I'm assuming like most government regulatory bodies they looked at many studies and formed a consensus about what is safe using the available literature.
There's a big difference between seeing high concentrations of carbon dioxide as indicative of poor ventilation and seeing high concentrations of carbon dioxide itself as detrimental to cognitive function.
If it's not CO2 the real cause might be even more interesting, if a real negative effect does exist (which it seems to do, given the recent studies). I find it interesting that
1) they disagree based on the tests/methodology used
2) no one seems to be acknowledging the military research from back then (which I have to say, I didn't know about myself).
Re 2: Military research gets ignored all the time despite (because?) it often outpacing academia by decades. Not sure exactly why this happens, just wanted to note this phenomenon isn't specific to CO2 levels and cognition.
Maybe, Military has strong incentive to conclude that CO2 level not affecting the soldier's intellectual and physical activities so they don't need to spend extra cost for submarine to keep the CO2 level low.
The Military has very little cost constraints. If they can show that CO2 impacts negatively the performance of troops they will get funding as needed. They are not run like corporations at all.
I think the military has a strong incentive to not have submarine crews with impaired intellectual and physical activities so they can perform as designed.
Yes. The question of CO2 and the difficulty reconciling Satish with practically all other CO2 studies has been a question of interest to ggreer & me since it was first raised on LW years ago: http://lesswrong.com/r/discussion/lw/nk0/what_is_up_with_car...
Was just reading that through and idly wondering, if that was the only experiment getting such a result, and there is nothing obviously wrong with the methodology, was there anything else by accident in the tank or gas lines they used for the CO2?
Not the first explanation I would reach for. (What would have to be in those tanks? Nitrogen would be very noticeable and wouldn't do anything, oxygen would presumably help rather than harm, and so on.)
It isn't submarine crew sitting in those conference rooms.
Not to mention the dreaded so-called "open-spaces". The tasks are completely different and no one gets half a year time off the tub. So the studies you cited are irrelevant.
In fact, inadeqate air quality was one of the three main reasons (two other being interruptions and commute time) that drove me to exclusively remote work 10 years ago. It took a lab-grade CO2 detector and some references to half-century old health standards to make the first step, but it worked.
2 hours in a meeting room is just plain exhausting, I'm 100% certain than I am more willing to compromise or walk out with shitty decisions by the end of it.
Thank you for linking some studies! This is very interesting to me, since I have noticed CO2 levels having a major effect on my work routine.
There is a CO2 sensor on my desk for 10 years already. Generally it is around 650 ppm during a working day but occasionally the building's ventilation system's power trips and air movement suddenly decreases. This causes CO2 levels to rise fast - once they hit 900-1000 ppm, I can definitely feel a decrease in my ability to focus and think clearly (and yes, I feel it even before looking at the numbers, ha!).
Obviously silly single anecdote but subjectively the link is very strong for me!
PS. On a sad note is that I remember the days when coming to work in the morning meant the CO2 level was at 350 ppm. These days clean air is 450 ppm in this city!
What if people are just dumber in crowds? I can imagine that as a psychological effect of heightened social awareness/interaction. Part of our cognitive capacity goes to that.
The US Navy's submarines are run with CO2 levels varying from 300-11,300ppm.[1] The military did plenty of studies in the 60s and 70s and failed to find significant cognitive effects in environments as high as 4% CO2.[2]
> Thus, CO2 at 40,000 ppm for 2 weeks did not affect performance on multiple tests of cognitive function in physically fit young airmen, a population probably not unlike submariners.
> A number of studies suggest that CO2 exposures in the range of 15,000-40,000 ppm do not impair neurobehavioral performance. Schaefer (1961) reported that 23 crewmen exposed to CO2 at 15,000 ppm for 42 days in a submarine showed no psychomotor testing effects but showed moderate increases in anxiety, apathy, uncooperativeness, desire to leave, and sexual desire.
> In a 5-day exposure of seven subjects at a CO2 concentration of 30,000 ppm, Glatte et al. (1967) reported no effects on hand steadiness, vigilance, auditory monitoring, memory, or arithmetic and problem solving performance.
> CO2 exposure did not affect performance on the tracking task or any of the six RPM subtests (Storm and Giannetta 1974).
There's also an argument from biology. When sitting around, people exhale 4-5% CO2. That's 40,000-50,000ppm. An extra 2,000ppm is far less than the variance across a typical breath, and it won't increase ppCO2 in the blood stream nearly as much as standing up and walking around. If CO2 hurt cognition as badly as these studies claim, then even minor physical exertion should turn people into drooling idiots.
It's for these reasons that I am extremely skeptical of the recent claims about CO2 impairing cognition.
1. https://www.nap.edu/read/11170/chapter/5#47
2. https://www.nap.edu/read/11170/chapter/5#54