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On whether changes in bedroom CO2 levels affect sleep quality

gwern.net

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Re: On whether changes in bedroom CO2 levels affect sleep quality

#71

Post by graeme »

tux1968 wrote: post #46
graeme wrote: post #41

Earlier quoted context omitted.

Those scrub the air of pollutants. No way they lower co2 sufficiently though. Plants reduce co2 by growing. Which they do....slowly. By contrast a human will spike the air in a room quickly by breathing.

That's interesting, I was just linking the article because it was talking specifically about co2 and NASA recommendations. In fairness, it didn't give any hard numbers on what to expect.

I think the author of the piece just made a poor inference. Air cleaning isn't necessarily the same as lowering co2.

That said, seems there are some succulents that do most of their co2 intake at night. Those would work best for co2. But you would need....at least 30-40 of them.

Opening a window, by contrast, works extremely well, and quickly. However, this requires non-polluted outside air. Else you're exchanging lower co2 for pollutants.

https://gerrieswart.com/2018/09/06/using-plants-to-improve-y...

Re: On whether changes in bedroom CO2 levels affect sleep quality

#73

Post by simulate »

Scott Alexander (slatestarcodex) provided a meta-study and also described how reducing CO2 in his cottage reduced headaches, fatigue, and poor sleep: https://slatestarcodex.com/2018/08/23/carbon-dioxide-an-open...

After reading this, I got a Netatmo CO2 monitor like Scott and Gwern. I found that CO2 peaked in my bedroom at around 1500 PPM at 6 AM with the door closed and that I could keep it under 500 PPM with the door open or a window open.

Scott Alexander also suggests getting around 10 succulents, if you don't want to open a door or a window.

Edit: Scott Alexander also published these survey results from other people who experimented with reducing CO2 in their homes: https://slatestarcodex.com/2018/10/04/nighttime-ventilation-...

Re: On whether changes in bedroom CO2 levels affect sleep quality

#74

Post by Robotbeat »

clairity wrote: post #22
bizzleDawg wrote: post #16

I've worked on environmental sensing iot projects and have seen the cost of co2 sensors. Almost all the cheap ones are VOC sensors which infer a co2 level by assuming the VOC output is from humans (rather than paint for example). Given the cost of the device I would be amazed if it wasn't a VOC based sensor. The cheapest CO2 sensors I've seen are well over $250, even in bulk. CO2 is quite innert, so it requires very…

i’ve noticed this casually as well. i bought an airthings wave plus [0] a few months ago and the co2 and total voc readings seem pretty (but not perfectly) correlated. i live in a drafty pre-war building and my co2 peaks at around 1500-1600 ppm at night with doors and windows closed. it troughs at around 500 during the day when i have the doors and windows open (~400 is ambient from what i understand). tvocs typicall…

413ppm is now ambient. Goes up higher every year (with a small amount of seasonal variation).

By 2100, we may be at 800ppm if we continue and/or accelerate fossil burning (4 degrees C trajectory). https://www.co2.earth/2100-projections

Already a middling stuffy room, and would increase indoor levels 400ppm over today.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#75

Post by graeme »

greenleaf2 wrote: post #54

There's one big problem with this entire idea of co2 levels affecting sleep quality or humans in general: Even though there are cognitive effects of CO2, most often the CO2 levels in indoor rooms are simply a sign of low oxygen levels. In fact, there should be an inverse relationship between CO2 and oxygen in rooms. So an experiments would need to take this into account and supply pure oxygen to make up for the oxyge…

Good observation. That said, co2 and o2 should move pretty much in tandem if the source of high co2 is human breathing + limited ventilation, right?

This could potentially account for why no ill effects of high co2 were found in submarines. Presumably o2 supply there is well maintained.

Do household air quality standards include o2 levels?

Re: On whether changes in bedroom CO2 levels affect sleep quality

#76

Post by chillwaves »

invalidusernam3 wrote: post #63
skuhl wrote: post #25

Fire safety experts recommend that bedroom doors be closed at night: https://closeyourdoor.org/

The fire safety song on that site is hilarious: https://www.youtube.com/watch?v=Uu9ReCQgvv4

That was way more entertaining than I expected. Shame they don't have many views.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#77

Post by andor »

forthispurpose wrote: post #57
bizzleDawg wrote: post #16

I've worked on environmental sensing iot projects and have seen the cost of co2 sensors. Almost all the cheap ones are VOC sensors which infer a co2 level by assuming the VOC output is from humans (rather than paint for example). Given the cost of the device I would be amazed if it wasn't a VOC based sensor. The cheapest CO2 sensors I've seen are well over $250, even in bulk. CO2 is quite innert, so it requires very…

Can you recommend the lowest cost CO2 sensor that one can buy that would give reliable readings?

The "TFA Dostmann AirCO2ntrol" devices are popular in Germany. Searching for "co2 meter" on Amazon.com one of the top results is an identical looking device.

It measures with an infrared spectroscopy-based sensor, which should be quite accurate. There are a few good software packages for recording data, e.g. https://github.com/vfilimonov/co2meter.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#78

Post by DocG »

graeme wrote: post #40
DocG wrote: post #29

I was lucky to get my hands on 5 proper co2 sensors from university, while I was teaching and working. So plenty of test places. What I found: -Just a couple of hours in a office, without ventilation spikes the co2 enough to make everyone dizzy and tired by the end of the day. Keeping eye on the meter and ventilating properly, increased everyones productivity and people werent so tired by the end of the day. - Classr…

What level was it at when you started noticing those effects? And how did you measure productivity? I have a sensor and try to keep readings low. My girlfriend isn't quite convinced though, especially in winter....

Around over 2000 I think. Less than 1000 would be ideal, I think outside is around 400.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#79

Post by 05 »

dschuler wrote: post #17
bizzleDawg wrote: post #16

I've worked on environmental sensing iot projects and have seen the cost of co2 sensors. Almost all the cheap ones are VOC sensors which infer a co2 level by assuming the VOC output is from humans (rather than paint for example). Given the cost of the device I would be amazed if it wasn't a VOC based sensor. The cheapest CO2 sensors I've seen are well over $250, even in bulk. CO2 is quite innert, so it requires very…

I got an NDIR CO2 sensor on AliExpress for $20. Do you think one of those would just have low accuracy or be uncalibrated?

Just test/calibrate them outside (400-ish ppm). Even if absolute measurements are bogus, they should do just fine to figure out whether it’s time to open the window..
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