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The most famous carbon dioxide absorber

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Re: The most famous carbon dioxide absorber

#71

Post by OutOfHere »

mppm wrote: post #70
londons_explore wrote: post #37

Anyone selling house-size CO2 absorbers to keep CO2 in my house to more like pre-industrial 200ppm rather than the 800ppm that's more common of house air in cities?

Honest question: Why would you want to? The average CO2 concentration in your lungs is something like 20,000 ppm, so it doesn't matter much whether ambient CO2 is at 200ppm or 800ppm. Other aspects of air quality do matter, but I'm highly skeptical about the value of capturing CO2 in your house.

Are you not familiar with any of the research linking high CO2 with harmed cognition and harmed alertness? It is manifest at as low as 800 ppm, certainly at 1000 ppm, and personally even at 600 ppm for me. There is good reason to want the preindustrial level that humans lived with for almost their entire history.

Re: The most famous carbon dioxide absorber

#72

Post by OutOfHere »

kimixa wrote: post #69
teekert wrote: post #63

Earlier quoted context omitted.

If you own a CO2 sensor you know that even at 5000 it’s not “easily detectable”… I know what is said about cognitive abilities and CO2 but I guess that’s hard to feel yourself. Moreover I doubt those results. Humans start to die at 10%, that’s (if I’m not mistaken) 100.000 ppm. Ive had a CO2 sensor for years, take it with me usually. In the beginning I was quite shocked, but I’m starting to doubt all the bad things s…

Air you breathe out is around 40 thousand ppm (and higher during exertion), and the air in the lungs isn't completely replaced every breath - I doubt there's much measurable difference at the actual alveoli at the levels we're talking about. You'll probably get more of a difference if you're breathing deeper and faster, or just got up to get a coffee or similar. And interestingly there are studies that show that brea…

High CO2 most definitely impairs cognitive performance as shown in many studies, and also backed up by substantial personal experience.

Re: The most famous carbon dioxide absorber

#73

Post by mppm »

OutOfHere wrote: post #71
mppm wrote: post #70

Earlier quoted context omitted.

Honest question: Why would you want to? The average CO2 concentration in your lungs is something like 20,000 ppm, so it doesn't matter much whether ambient CO2 is at 200ppm or 800ppm. Other aspects of air quality do matter, but I'm highly skeptical about the value of capturing CO2 in your house.

Are you not familiar with any of the research linking high CO2 with harmed cognition and harmed alertness? It is manifest at as low as 800 ppm, certainly at 1000 ppm, and personally even at 600 ppm for me. There is good reason to want the preindustrial level that humans lived with for almost their entire history.

Yes, I've seen such research, but I am highly skeptical, to put it very mildly. This actually being the case is simply implausible from the physiological perspective, considering the very high (and constantly changing) concentration of CO2 in the lungs and in the bloodstream. Early research with Navy submariners was consistent with this -- no detectable impairment below 1% (10,000 ppm) and clear impairment at 3-4%. Later long term studies with 0.5% exposure (5,000 ppm) also found nothing. I put the recently popular research showing cognitive impairment as low as 600 ppm in the same mental niche as vitamin megadosing -- underpowered, low quality research with no basis in human physiology.

That said, CO2 can often serve as an easily measurable proxy for stuffy air, which can contain particulates, formaldehyde and other organic exhalations which may actually have some effect (psychological, if nothing else). But this just calls for ventilation and air filtering, not CO2 scrubbing.

Re: The most famous carbon dioxide absorber

#74

Post by OutOfHere »

mppm wrote: post #73
OutOfHere wrote: post #71

Earlier quoted context omitted.

Are you not familiar with any of the research linking high CO2 with harmed cognition and harmed alertness? It is manifest at as low as 800 ppm, certainly at 1000 ppm, and personally even at 600 ppm for me. There is good reason to want the preindustrial level that humans lived with for almost their entire history.

Yes, I've seen such research, but I am highly skeptical, to put it very mildly. This actually being the case is simply implausible from the physiological perspective, considering the very high (and constantly changing) concentration of CO2 in the lungs and in the bloodstream. Early research with Navy submariners was consistent with this -- no detectable impairment below 1% (10,000 ppm) and clear impairment at 3-4%. L…

It is me who is skeptical of extremely healthy test subjects in their early 20s being used to define what's healthy for the population at large. As for vitamin dosing, there is most certainly an optimal dose and form of each vitamin, somewhere between its lower and upper limits.

Offices have high ventilation but also high CO2, and the effect shows clearly in a meeting room, putting people to sleep.

Re: The most famous carbon dioxide absorber

#75

Post by immibis »

headsupernova wrote: post #67
teekert wrote: post #63

Earlier quoted context omitted.

If you own a CO2 sensor you know that even at 5000 it’s not “easily detectable”… I know what is said about cognitive abilities and CO2 but I guess that’s hard to feel yourself. Moreover I doubt those results. Humans start to die at 10%, that’s (if I’m not mistaken) 100.000 ppm. Ive had a CO2 sensor for years, take it with me usually. In the beginning I was quite shocked, but I’m starting to doubt all the bad things s…

I've found the same. And thinking it through, I can't come up with a mechanism for how a few more CO2 molecules bopping around in a sea of nitrogen and oxygen changes anything about how my lungs exchange the CO2 in my body with air around me. These counts are ppm, nothing!

If there's twice as much CO2 in the air, twice as much CO2 goes from the air into your blood.

Re: The most famous carbon dioxide absorber

#77

Post by teekert »

OutOfHere wrote: post #72
kimixa wrote: post #69

Earlier quoted context omitted.

Air you breathe out is around 40 thousand ppm (and higher during exertion), and the air in the lungs isn't completely replaced every breath - I doubt there's much measurable difference at the actual alveoli at the levels we're talking about. You'll probably get more of a difference if you're breathing deeper and faster, or just got up to get a coffee or similar. And interestingly there are studies that show that brea…

High CO2 most definitely impairs cognitive performance as shown in many studies, and also backed up by substantial personal experience.

Double blind personal experience?

Re: The most famous carbon dioxide absorber

#78

Post by teekert »

immibis wrote: post #75
headsupernova wrote: post #67

Earlier quoted context omitted.

I've found the same. And thinking it through, I can't come up with a mechanism for how a few more CO2 molecules bopping around in a sea of nitrogen and oxygen changes anything about how my lungs exchange the CO2 in my body with air around me. These counts are ppm, nothing!

If there's twice as much CO2 in the air, twice as much CO2 goes from the air into your blood.

CO2 enters the blood in the body, it comes out of the lungs. If you breath too hard you loose too much CO2 and your blood pH will go up. That’s why you breathe into a bag when hyper ventilating, to keep that precious CO2 in.

Re: The most famous carbon dioxide absorber

#79

Post by kragen »

kragen wrote: post #50
londons_explore wrote: post #37

Anyone selling house-size CO2 absorbers to keep CO2 in my house to more like pre-industrial 200ppm rather than the 800ppm that's more common of house air in cities?

You'd only need a few hundred grams of triethanolamine if you regenerate it several times a day (with a vent to outdoors), but there are probably some spill risks and maybe mist. Soda-lime is cheaper but requires inconveniently high temperatures to regenerate, which probably result in unwanted emissions requiring mitigation as well as too much energy use. Regular lime (without the soda) avoids the emissions but takes…

A caution I should have thought to include: if you do this to remove the carbon dioxide you exhale, you need to make sure you have enough ventilation that you don't asphyxiate. In the absence of carbon dioxide to tell you to seek fresh air, you won't notice the oxygen levels dropping; you'll just get stupid, then lose consciousness, then die. Homemade rebreathers have a high fatality rate. I don't think such good sealing is likely at the scale of an entire house unless it's literally underwater or something. But keep it in mind.
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