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Training my sense of CO2 ppm

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Re: Training my sense of CO2 ppm

#2
people on supplemental oxygen sometimes get CO2 problems; the oxymeter shows good numbers but they're acting drunk or feeling poorly otherwise.

Apparently its sneaky and cumulative; a few moments wont do much but as time goes on you get fizzier.

Re: Training my sense of CO2 ppm

#4

I've bought [1] and coupled it with Zabbix using [2]. Now I have a pretty realtime graph and a strong reasoning to air my room more often. [1] https://www.tfa-dostmann.de/en/product/co2-monitor-airco2ntr... [2] https://codeberg.org/pf-monitoring/airco2ntrold

Not sure if they still make them with speakers that sound like life support monitors in the hospital, but if the beeping is too annoying you can just open the back and break off the speaker with pliers.

Re: Training my sense of CO2 ppm

#5
Is there any kind of CO2 scrubbing that's at all practical for home? I'm curious what the effects would be of going below ambient/outdoor levels, especially since those are rising (if slowly).

Re: Training my sense of CO2 ppm

#6
I have a qingping air monitor lite, which was around $70.

It also measures PM10 and PM2,5 which helped me show that my wood furnace is indeed leaking something sometimes when I noticed it smelling weird.

Re: Training my sense of CO2 ppm

#7
I think the elephant in the room is calibration of the CO2 detector.

When I looked into this a few years ago, I couldn't find any accuracy guaranties for CO2 meters marketed for households / greenhouses.

The closest thing I could find were laboratories that could test CO2 meters in chambers with known CO2 concentrations. But IIRC the pricing for those labs was prohibitively expensive.

- There were literally no guaranteed accuracy bounds for the meters I looked at. So they could be off by 3x reality for all I know.

- Their calibration systems relied on an assumed CO2 concentration for outside air. But even if the calibration system ensured that the meter would report the right number for that CO2 concentration, there was no information about how accurate the calibrated meter would be at other CO2 concentrations. Nor information about how the meter's numbers would be off when the CO2 levels observed during calibration differed from the level assumed by the calibration logic.

These limitations might not be a problem for some applications. But they could be an issue when people want to relate their meters' readings to the numbers used in various research publications.

Re: Training my sense of CO2 ppm

#8
I feel terrible above like 900/1000ppm but I’m sure it’s also a good proxy for whatever other garbage and voc’s are in the air. When my monitor reaches 800 I’ll throw my window exhaust fan on for a few hours to circulate the air in my home.

Re: Training my sense of CO2 ppm

#9

I think the elephant in the room is calibration of the CO2 detector. When I looked into this a few years ago, I couldn't find any accuracy guaranties for CO2 meters marketed for households / greenhouses. The closest thing I could find were laboratories that could test CO2 meters in chambers with known CO2 concentrations. But IIRC the pricing for those labs was prohibitively expensive. - There were literally no guaran…

I own an Awair unit, and as far as I can tell it attempts to calibrate itself based on outside atmosphere having 400 ppm... but that value is constantly going up and is now like 415, so I figure my unit must be at least a few percent off.

Re: Training my sense of CO2 ppm

#10
post #5

Is there any kind of CO2 scrubbing that's at all practical for home? I'm curious what the effects would be of going below ambient/outdoor levels, especially since those are rising (if slowly).

From some (personal) research I did several years ago, I think good ventilation is by far the biggest concern.

A well-sealed, occupied room can build up significant CO2 levels pretty quickly. In my particular case, one person, not exercising, could bring CO2 above 800ppm (reported) in just a few hours.

So I think lack of ventilation causes way, way more excess CO2 than is caused by recent increases in atmospheric CO2. At least in my suburban neighborhood; maybe it's a lot worse in a dense city.

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