7 ms·

I've heard some people can (train themselves to?) tell when the CO2 level rises in the room. Has anyone here managed to? If so, do you have any tips on how (or

I've heard some people can (train themselves to?) tell when the CO2 level rises in the room. Has anyone here managed to? If so, do you have any tips on how (or whether!) to do this, and/or what it feels like (if it's possible to give any vague explanation in text)?

zahrc 4y ago
It feels stuffy. I get headaches and get tired. When you open a window it’s almost like instant relief
- JohnBooty 4y ago
  Yeah the thing we've casually called "stuffy air" forever is, essentially, 100% equivalent with high CO2 levels. There are some other situations where non-"stuffy" air might have too much CO2, I guess. I guess you could pump CO2 into a room with cool, dry air. But barring a contrived situation like that, stuffy=CO2.
quakeguy 4y ago
That’s called grandpa-tells-you-to-go-sleep Syndrom, it is harmless usually.
afusalan 4y ago
> I've heard some people can (train themselves to?) tell when the CO2 level rises in the room. Has anyone here managed to? If so, do you have any tips on how (or whether!) to do this, and/or what it feels like (if it's possible to give any vague explanation in text)? The best indication is feeling sleepy. Once you become sleepy go outside and take deep breaths, then you understand the sensation difference between O2 and CO2.
- dataflow 4y ago
  Unfortunately that doesn't seem to work for me. Right now my room has > 1200ppm CO2 (due to closed doors/windows) but I don't feel sleepy at all, or any differently (that I can discern) from when it's < 600ppm. Do you know if it needs to be significantly higher for that feeling to kick in? If so, approximately how much?
  - colechristensen 4y ago
    Have a meter going and look at it. I’d describe it as a feeling in my lungs as i breathe I can start to feel above 800ppm. The air feels heavy maybe? I think some people are more sensitive to it than others.
    - OJFord 4y ago
      Have you tested yourself by concentrating on your breathing a bit and then guessing the level before you look at it? I'm not disbelieving, just curious.
  - afusalan 4y ago
    Hmm, I've never had the device to measure the levels tbh. I can say I'm fairly sensitive to air as i do breathwork regularly. 1200 ppm sounds a lot, maybe that's coming from not just CO2 in the air but maybe dust particles, smoke, food vapour, or chemicals such as odor, ozone, perfume, house cleaning products etc.
  - JohnBooty 4y ago
    Unfortunately that doesn't seem to work for me. Right now my room has > 1200ppm CO2 (due to closed doors/windows) but I don't feel sleepy at all It's a very gradual difference. If you're doing something interesting at 1000-2000ppm you probably won't feel sleepy, but it will probably be harder to focus on something you don't find stimulating and you'll be more inclined to feel sleepy.
    - dataflow 4y ago
      Interesting, I guess I can try to see if I can notice that. Thanks!
- pistoriusp 4y ago
  I always assumed that this was somewhat natural, but it may just be my upbringing. I grew up in a warm country without air conditioning, so open windows were the only way. Then moved to a cold country and noticed the sensation. I put 1-1 together. In my case my face, specifically my forehead, feels warm. Not to the touch, but more to the nerves. I think it may be different for different people.
rwmj 4y ago
At KVM Forum 2019 [1] there was a particular theatre where the enclosed space with many people and lack of ventilation was very obvious. I felt dizzy and sleepy a few times at lectures there (and nowhere else). No training needed! Edit: It was the room shown in this picture: [2] [1] https://events19.linuxfoundation.org/events/kvm-forum-2019/attend/venue-travel/ https://events19.linuxfoundation.org/events/kvm-forum-2019/a... [2] https://locations.filmfrance.net/location/lyon-convention-centre-amphitheatre https://locations.filmfrance.net/location/lyon-convention-ce...
quantum_magpie 4y ago
I can't say anything about training it, but beside the usual sleepiness, at >1000 ppm I get a feeling of swelling eyeballs and tingling teeth/dentures. I've been this way as long as I remember.
dzhiurgis 4y ago
I’m not very sensitive to it but I start getting stuffy nose, especially overnight.
JohnBooty 4y ago
Has anyone here managed to? If so, do you have any tips on how (or whether!) to do this I have, basically. The easiest (only?) way to do this is simply to have a CO2 sensor, and pay attention to it. You'll quickly learn to intuitively correlate what you're seeing on the sensor with what you're experiencing. After a while you'll be able to vaguely approximate the CO2 levels without even looking at the sensor. Of course, you won't be able to pinpoint an exact CO2 level, but you'll be able to tell when it's e.g. > 1000. You've already been doing this your whole life, of course. You've already been distinguishing between "fresh" and "stuffy" air. "Stuffy" air is just our colloquial term for air with undesirably high CO2.
- dataflow 4y ago
  I've been trying that; I do have a sensor. I can probably guess the CO2 level with decent accuracy, but that's not because I feel any different—but rather because I know how long I've been in the room with closed doors/windows. With respect to "stuffy" vs. "fresh" air, I don't know whether my sense of it is the same as others'. What I would call "stuffy" is probably affected by humidity, dust, odors, plants, etc. and not just CO2.
  - JohnBooty 4y ago
    With respect to "stuffy" vs. "fresh" air, I don't know whether my sense of it is the same as others'. What I would call "stuffy" is probably affected by humidity, dust, odors, plants, etc. and not just CO2. That's fair. I'm not sure if I'm really sensing CO2 levels, or if I'm wholly reliant on those proxy factors that you mentioned. I know that when my wife turns on the gas oven downstairs I can definitely feel a difference even if I wasn't aware she was turning it on and the CO2 meter confirms the CO2 spike. But even then, maybe I'm just "sensing" it via proxy factors like smell. In practice it probably doesn't matter all that much. Those proxy factors are really good proxies. It's hard to think of real-world scenarios where they wouldn't be.
- lucb1e 4y ago
  Don't you think those 'experience correlations' are based on proxy parameters? Temperature being one of the main ones I would expect. I don't experience water as fresh unless it is cold, for example.
iofiiiiiiiii 4y ago
I have the unfortunate pleasure of being very sensitive to CO2 levels. At around 800-900 ppm I get a general feeling that something is abnormal. If it goes to 1000 ppm then I can usually tell that I am not thinking well anymore. It is a similar feeling to being slightly drunk - for example, I start a thought but find it difficult to carry it through to the conclusion. Before I got a CO2 meter, I could always tell within hours when my building's flaky central ventilation fan had failed because I simply felt something was off. Unless you are similarly cursed/blessed, just get a CO2 meter. I could not imagine learning this, it is like learning to feel temperature.

zahrc 4y ago

It feels stuffy. I get headaches and get tired. When you open a window it’s almost like instant relief

JohnBooty 4y ago
Yeah the thing we've casually called "stuffy air" forever is, essentially, 100% equivalent with high CO2 levels. There are some other situations where non-"stuffy" air might have too much CO2, I guess. I guess you could pump CO2 into a room with cool, dry air. But barring a contrived situation like that, stuffy=CO2.

quakeguy 4y ago

That’s called grandpa-tells-you-to-go-sleep Syndrom, it is harmless usually.

afusalan 4y ago

> I've heard some people can (train themselves to?) tell when the CO2 level rises in the room. Has anyone here managed to? If so, do you have any tips on how (or whether!) to do this, and/or what it feels like (if it's possible to give any vague explanation in text)? The best indication is feeling sleepy. Once you become sleepy go outside and take deep breaths, then you understand the sensation difference between O2 and CO2.

dataflow 4y ago
Unfortunately that doesn't seem to work for me. Right now my room has > 1200ppm CO2 (due to closed doors/windows) but I don't feel sleepy at all, or any differently (that I can discern) from when it's < 600ppm. Do you know if it needs to be significantly higher for that feeling to kick in? If so, approximately how much?
- colechristensen 4y ago
  Have a meter going and look at it. I’d describe it as a feeling in my lungs as i breathe I can start to feel above 800ppm. The air feels heavy maybe? I think some people are more sensitive to it than others.
  - OJFord 4y ago
    Have you tested yourself by concentrating on your breathing a bit and then guessing the level before you look at it? I'm not disbelieving, just curious.
- afusalan 4y ago
  Hmm, I've never had the device to measure the levels tbh. I can say I'm fairly sensitive to air as i do breathwork regularly. 1200 ppm sounds a lot, maybe that's coming from not just CO2 in the air but maybe dust particles, smoke, food vapour, or chemicals such as odor, ozone, perfume, house cleaning products etc.
- JohnBooty 4y ago
  Unfortunately that doesn't seem to work for me. Right now my room has > 1200ppm CO2 (due to closed doors/windows) but I don't feel sleepy at all It's a very gradual difference. If you're doing something interesting at 1000-2000ppm you probably won't feel sleepy, but it will probably be harder to focus on something you don't find stimulating and you'll be more inclined to feel sleepy.
  - dataflow 4y ago
    Interesting, I guess I can try to see if I can notice that. Thanks!
pistoriusp 4y ago
I always assumed that this was somewhat natural, but it may just be my upbringing. I grew up in a warm country without air conditioning, so open windows were the only way. Then moved to a cold country and noticed the sensation. I put 1-1 together. In my case my face, specifically my forehead, feels warm. Not to the touch, but more to the nerves. I think it may be different for different people.

rwmj 4y ago

At KVM Forum 2019 [1] there was a particular theatre where the enclosed space with many people and lack of ventilation was very obvious. I felt dizzy and sleepy a few times at lectures there (and nowhere else). No training needed! Edit: It was the room shown in this picture: [2] [1] https://events19.linuxfoundation.org/events/kvm-forum-2019/attend/venue-travel/ https://events19.linuxfoundation.org/events/kvm-forum-2019/a... [2] https://locations.filmfrance.net/location/lyon-convention-centre-amphitheatre https://locations.filmfrance.net/location/lyon-convention-ce...

quantum_magpie 4y ago

I can't say anything about training it, but beside the usual sleepiness, at >1000 ppm I get a feeling of swelling eyeballs and tingling teeth/dentures. I've been this way as long as I remember.

dzhiurgis 4y ago

I’m not very sensitive to it but I start getting stuffy nose, especially overnight.

JohnBooty 4y ago

Has anyone here managed to? If so, do you have any tips on how (or whether!) to do this I have, basically. The easiest (only?) way to do this is simply to have a CO2 sensor, and pay attention to it. You'll quickly learn to intuitively correlate what you're seeing on the sensor with what you're experiencing. After a while you'll be able to vaguely approximate the CO2 levels without even looking at the sensor. Of course, you won't be able to pinpoint an exact CO2 level, but you'll be able to tell when it's e.g. > 1000. You've already been doing this your whole life, of course. You've already been distinguishing between "fresh" and "stuffy" air. "Stuffy" air is just our colloquial term for air with undesirably high CO2.

dataflow 4y ago
I've been trying that; I do have a sensor. I can probably guess the CO2 level with decent accuracy, but that's not because I feel any different—but rather because I know how long I've been in the room with closed doors/windows. With respect to "stuffy" vs. "fresh" air, I don't know whether my sense of it is the same as others'. What I would call "stuffy" is probably affected by humidity, dust, odors, plants, etc. and not just CO2.
- JohnBooty 4y ago
  With respect to "stuffy" vs. "fresh" air, I don't know whether my sense of it is the same as others'. What I would call "stuffy" is probably affected by humidity, dust, odors, plants, etc. and not just CO2. That's fair. I'm not sure if I'm really sensing CO2 levels, or if I'm wholly reliant on those proxy factors that you mentioned. I know that when my wife turns on the gas oven downstairs I can definitely feel a difference even if I wasn't aware she was turning it on and the CO2 meter confirms the CO2 spike. But even then, maybe I'm just "sensing" it via proxy factors like smell. In practice it probably doesn't matter all that much. Those proxy factors are really good proxies. It's hard to think of real-world scenarios where they wouldn't be.
lucb1e 4y ago
Don't you think those 'experience correlations' are based on proxy parameters? Temperature being one of the main ones I would expect. I don't experience water as fresh unless it is cold, for example.

iofiiiiiiiii 4y ago

I have the unfortunate pleasure of being very sensitive to CO2 levels. At around 800-900 ppm I get a general feeling that something is abnormal. If it goes to 1000 ppm then I can usually tell that I am not thinking well anymore. It is a similar feeling to being slightly drunk - for example, I start a thought but find it difficult to carry it through to the conclusion. Before I got a CO2 meter, I could always tell within hours when my building's flaky central ventilation fan had failed because I simply felt something was off. Unless you are similarly cursed/blessed, just get a CO2 meter. I could not imagine learning this, it is like learning to feel temperature.