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0 pointswcoenen2mo ago0 comments

> Noticeable cognitive impairment starts in the 700-1000ppm range

The US navy failed to detect such effects in submarine crew, even at much higher levels like 10,000 ppm.

Another reason to be skeptical is that exhaled breath is 4% CO2 (40,000 ppm!). Therefore a few thousand extra ppm in the inhaled air should not make much of a difference to the homeostasis mechanisms in our bodies.

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progbits2mo ago

See my sibling comment for meta-analysis that disagrees with you. Would love to see citation for those navy experiments.

wcoenenOP2mo ago

Citation for a 2018 study with submarine-qualified sailors: https://pubmed.ncbi.nlm.nih.gov/29789085/

hinkley2mo ago

Have you ever met a submariner? These are not normal humans. That’s some serious cherry picking of data.

hinkley2mo ago

Back in the 00’s I worked at a place where we were still ignoring WLB and would work until seven a couple nights a week on average. But the building AC shut off at 6. A few of us noticed that the later it got the worse our decisions and the worse the bickering and we eventually got to the policy that anyone could declare Deciding done for the evening when they realized we were just tired, hot, and stuffy. Every minute past about 6:15 got worse, particularly in summer.

I’m sure the CO2 was part of it but lack of circulation also means increasing temperature, especially with a bunch of people in a small meeting room. Long meetings themselves are a problem and any excuse to call it early is probably worth it even if it’s not entirely true.

_yb2s2mo ago

I don’t need to look at studies in other people, I notice and feel the effects directly at high CO2 levels, such that I can tell when it it too high before checking the meter.

I’d need to look at the study, but I also suspect the submariners would be used to high CO2, and also not experienced enough in doing focused creative or knowledge work for impaired abilities there to be detectable.

Ey7NFZ3P0nzAe2mo ago

Med resident here.

Please consider the possibility that you can accurately detect increased CO2 (it increases your breathing rate almost instantly for example) without it causing impairement.

_yb2s2mo ago

Even if you are right and there is no objectively measurable impaired abilities, the things I can detect directly are themselves extremely undesirable.

I feel irritable, and fatigued/sleepy when CO2 is high. Increased breathing rate by itself activates an undesirable sympathetic nervous system response, that anyone can notice immediately with deliberate breathwork.

Also, it seems likely to me that the same poor air exchange that leads to high co2 causes respiratory disease to spread more rapidly, and with a higher initial viral titer.

j / k navigate · click thread line to collapse

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progbits2mo ago

See my sibling comment for meta-analysis that disagrees with you. Would love to see citation for those navy experiments.

wcoenenOP2mo ago

Citation for a 2018 study with submarine-qualified sailors: https://pubmed.ncbi.nlm.nih.gov/29789085/

hinkley2mo ago

Have you ever met a submariner? These are not normal humans. That’s some serious cherry picking of data.

hinkley2mo ago

_yb2s2mo ago

I don’t need to look at studies in other people, I notice and feel the effects directly at high CO2 levels, such that I can tell when it it too high before checking the meter.

Ey7NFZ3P0nzAe2mo ago

Med resident here.

Please consider the possibility that you can accurately detect increased CO2 (it increases your breathing rate almost instantly for example) without it causing impairement.

_yb2s2mo ago

Even if you are right and there is no objectively measurable impaired abilities, the things I can detect directly are themselves extremely undesirable.

Also, it seems likely to me that the same poor air exchange that leads to high co2 causes respiratory disease to spread more rapidly, and with a higher initial viral titer.

j / k navigate · click thread line to collapse