12 ms·

Rising CO2 levels may trigger cognitive impairment, says new study

161 points by conse_lad 6y ago

deleted 6y ago
[deleted]
graeme 6y ago
This does not appear to be a new study on the effects of CO2. It only mentions there will be more indoor co2 as a result of combustion? Scihub didn’t work for this one so I can’t be sure. I’m quite interested in this topic, and there are a small number of studies indicating the issue may be real. However, it is unclear this adds to them. IF the issue is real it is nonetheless useful to know what this study measures.
- pas 6y ago
  It's open access: https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2019GH000237 https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/201... It doesn't seem to be a trial, it's more like a deduction (basically model fitting) from available data.
wh-uws 6y ago
This one of those things that sounds silly but is actually very easy to test and see it can be a real issue. Tom Scott did a great video on it a while back https://youtu.be/1Nh_vxpycEA https://youtu.be/1Nh_vxpycEA Do yourself a favor and get an air quality monitor like an awair https://getawair.com/ https://getawair.com/ and monitor the levels. Making sure they are good in whatever indoor areas you spend a good amount of time in is a night and day difference cognitively.
- zbrozek 6y ago
  Anybody know of something similar which doesn't exfiltrate data from my home?
  - detaro 6y ago
    For CO2 specifically, one offline option is the "CO2Meter RAD-0301", also available as "TFA Dostmann AirCO2ntrol Mini" and possibly other labels. They have an unofficial USB interface too: https://news.ycombinator.com/item?id=22764488 https://news.ycombinator.com/item?id=22764488
  - ohm 6y ago
    IQAir AirVisual Pro works offline. It's expensive though.
  - Lammy 6y ago
    Open your windows at least a few inches. Let some breeze through. Don't worry about the AQI number :)
- throwquestion24 6y ago
  Testing is fun. But what do you do then? Open the windows? Remove the cars from the freeway down the street?
  - jaggederest 6y ago
    Anything that moves the air is fine. And yes, opening windows would be a sensible thing to do in that context. That said, I'm not sure I buy the thesis as a whole. As far as I am aware, last time this came up, the Navy has done pretty detailed tests on CO2 concentration as a result of submarine warfare and found no significant impairments up to 1200ppm.
  - Arainach 6y ago
    Opening the windows is a solid choice. I keep a CO2 monitor in my office. So long as I keep the door open, levels usually stay below 800ppm, but if I close the door they can climb rapidly within an hour or two. I have a CO2 meter tied to an alarm to remind me to open the window if they get too high. I probably should have it set to 800, but I found that to trigger too often so I upped it to 1200. I use a RAD-0301, which works fine as a monitor and an alarm by itself, but which I connect to a Raspberry Pi for dashboard purposes using the code shared here: https://news.ycombinator.com/item?id=22764488 https://news.ycombinator.com/item?id=22764488
  - kevingadd 6y ago
    If you have central heat/ac your thermostat might have a switch to convert it from 'auto' to 'on'. You can combine that with turning off the heat/cooling such that it's just a house/apartment-wide fan. I do that at night before going to bed to deal with poor airflow in my bedroom and according to my CO2 sensor, it works. It works correctly even if I leave it set to cool or heat, the thermostat still controls whether it's actually heating or circulating air. Likely what you have is the same.
  - Lammy 6y ago
    I wish there was a freeway down the street. Then the cars would be here and gone instead of idling in our local streets for fifteen minutes waiting to merge. Here's a real-world study of before and after they tore down two exits of the Central Fwy and built the horrible Octavia Blvd that necessitated a bunch of sidewalk closures and keeps killing cyclists: https://archive.sfcta.org/sites/default/files/content/Planning/CentralOctaviaCirculationStudy/Final%20Report%20Executive%20Summary.pdf https://archive.sfcta.org/sites/default/files/content/Planni...
- xoa 6y ago
  I don't know about the awair specifically, but it's worth being cautious about cheap air quality monitors. There seems to be little good standardized testing of them, and sometimes even major brands can have abysmal accuracy. See for example the EPA study "Evaluation of Emerging Air Sensor Performance" [1], some of them have very low or even zero correlation with reference monitors. It'd be nice to see some more uniform independent lab testing and marking standards there, or maybe there already are? I've rarely been able to find comprehensive evaluations however. At least it does look like the EPA is looking at them more, last year there was a very interesting webinar overview [2] of research being done on them. There are plenty of fully dumb plain monitors too, but since you picked a smart IOT one I'd personally really want to make sure it'd work LAN-only and supported a wide array of integrations. From a quick glance it's not clear the Awair does that, and it does not have HomeKit support for example. ---- 1: https://www.epa.gov/air-sensor-toolbox/evaluation-emerging-air-sensor-performance https://www.epa.gov/air-sensor-toolbox/evaluation-emerging-a... 2: https://www.epa.gov/research-states/low-cost-air-quality-sensors-webinar-archive https://www.epa.gov/research-states/low-cost-air-quality-sen...
- jack12 6y ago
  Anyone getting an air quality monitor specifically because of an interest in CO2 needs to be a bit wary, a lot of them claim to have a CO2 sensor but are actually just predicting CO2 levels based on other sensors designed to measure human occupancy. CO2 sensors are/were very popular for HVAC systems to use as a proxy reading of human occupancy levels and general air quality to meet air quality requirements. Now more modern (cheaper) air quality sensors are available which measure a mix of VOCs exhaled by people instead of CO2 but have an output mode that emulates the reading from a CO2 sensor at a similar occupancy level so that HVAC systems wouldn't have to redesign their control systems / formulas, usually marketed as "equivalent CO2" (or eCO2) readings. Because they're called eCO2 sensors while being cheaper and lower power than real CO2 sensors, many air quality monitors have been using them and then surfacing their readings as "CO2 levels" under the mistaken belief that they can use the sensor to measure CO2. But it won't measure environmental CO2 at all, just predict the amount of CO2 the humans in a room would typically generate. Which is all you need for air quality monitoring, but just be aware you're not actually measuring CO2 if that's what you're curious about. There are monitors with real CO2 sensors, but you'll want to look for a teardown to see what sensor is actually being used before you purchase. The Awair 2 seems to have a real NDIR CO2 sensor (Telaire T6703), for example: https://wiki.liutyi.info/display/CO2/Awair+2+inside#Awair2inside-CO2Sensor:AmphenolTelaireT6703-5K https://wiki.liutyi.info/display/CO2/Awair+2+inside#Awair2in...
- totetsu 6y ago
  Kurtis Baute's full experiment from Tom's video was very interesting. He tried to seal himself in a green house with plants to generate oxygen for a few days. https://youtu.be/PoKvPkwP4mM https://youtu.be/PoKvPkwP4mM
- throwaway9d0291 6y ago
  If people want a more flexible, less crazy expensive option, it's fairly straightforward to build a WiFi-connected sensor with an ESP32 devkit [0], an off-the-shelf sensor like the SCD30 [1] and ESPHome [2]. This is simple to assemble, will give you fairly good, repeatable readings, auto-calibration that performs pretty well and an open-source platform with full access to your data rather than a proprietary cloud application. Full cost should be ~$70, I'd expect assembly and flashing to take ~1h the first time. The most complicated thing you'll have to do from an electronics standpoint is solder on the pin header to the sensor, other than that it's just jumper wires and flashing over USB. No need for adding resistors or capacitors or anything like that. If you're not comfortable with soldering, I _think_ the evaluation kit for the SCD30 [3] comes with pre-assembled headers. There's also a third-party variant [4] that comes with a cable header you can break out [5]. I strongly recommend that you use the SCD30. I've tested a variety of sensor components from a variety of manufacturers and the SCD30 was by far the best performing. Other sensors have problems with auto-calibration in a residential environment so either give nonsense readings or drift without periodic manual calibration. However if you want something _really_ cheap, you can replace the SCD30 with the ~$20 MH-Z19 and the total price will be ~$30. The auto-calibration on these is utterly terrible however, so you'll need to manually calibrate it with fresh air every couple of months to compensate for drift. And as others have warned, beware of retail products. A lot of them have fake "CO2" or "eCO2" sensors that don't measure CO2 but try to guess it based on other measurements. These are completely useless and are not at all indicative of actual CO2 levels. [0]: Purchase: https://octopart.com/esp32-devkitc-32d-espressif+systems-92405929 https://octopart.com/esp32-devkitc-32d-espressif+systems-924..., info: https://www.espressif.com/en/products/devkits/esp32-devkitc/overview https://www.espressif.com/en/products/devkits/esp32-devkitc/... [1]: Purchase: https://octopart.com/scd30-sensirion-89692236?r=sp https://octopart.com/scd30-sensirion-89692236?r=sp, info: https://www.sensirion.com/en/environmental-sensors/carbon-dioxide-sensors/carbon-dioxide-sensors-co2/ https://www.sensirion.com/en/environmental-sensors/carbon-di... [2]: https://esphome.io/ https://esphome.io/ [3]: https://octopart.com/sek-scd30-sensor-sensirion-101025983?r=sp https://octopart.com/sek-scd30-sensor-sensirion-101025983?r=... [4]: https://www.seeedstudio.com/Grove-CO2-Temperature-Humidity-Sensor-SCD30-p-2911.html https://www.seeedstudio.com/Grove-CO2-Temperature-Humidity-S... [5]: https://www.seeedstudio.com/Grove-4-pin-Female-Jumper-to-Grove-4-pin-Conversion-Cable-5-PCs-per-PAck.html https://www.seeedstudio.com/Grove-4-pin-Female-Jumper-to-Gro...
inamberclad 6y ago
Finally, a good explanation for the state of the world! On a realistic note, this is a cause for concern for astronauts on the ISS. They experience chronic, significantly elevated ppCO2 levels (4 torr, vs 0.3 torr at sea level), which cases headaches and fatigue, and possibly what's known as the "space stupids," where very high-key, detail oriented people start messing up checklist items and don't perform nearly as well as they should.
- Tade0 6y ago
  I was wondering why remote work is sometimes so difficult for me, even though I've been doing it for years. Turns out I needed to let in some fresh air more often. Getting to 1000ppm of CO2 is remarkably easy in a room with 25 cubic metres of volume.
  - realharo 6y ago
    You can buy a cheap sensor, like the MH-Z19B, connect it to a Raspberry Pi Zero W (or just about anything else), and set a reminder to open the windows once the value rises above some threshold. Or just buy a finished product for this somewhere I guess.
    - hckr_news 6y ago
      Interesting thanks for the heads up
balnaphone 6y ago
From wearing COVID-19 masks? https://jamanetwork.com/journals/jama/fullarticle/2764955 https://jamanetwork.com/journals/jama/fullarticle/2764955 Quote: > Oxygen concentration inhaled by healthy subjects wearing a surgical mask covering an N95 respirator decreases to about 17%, and the concentration of carbon dioxide increases to about 1.2% - 3% in a short period of light work (2-3). Although participants did not show any obvious changes in physical function and did not have any discomfort ratings, the average carbon dioxide concentration inhaled was far higher than the limit of 0.1% of indoor carbon dioxide concentration in many countries. With prolonged mask wearing, untoward reactions may gradually appear. In another long-term study, after wearing an N95 mask for 12 hours the CO2 concentration of subjects increased to 41.0 mmHg, far higher than the baseline value of 32.4mm Hg at the beginning of the test (4). The subjects mainly reported headache, dizziness, feeling tired and communication obstacles. In real life, the situations and time of wearing masks are much longer than the above experimental research settings.
- Reason077 6y ago
  That's for an N95 respirator combined with a surgical mask. Most of us are just wearing surgical-type masks, and I doubt they make any difference to oxygen levels. (If they did, I'd be very worried about surgeons!)
- empath75 6y ago
  You can take the mask off for a while if you're starting to get uncomfortable, but yes, it's probabaly not good to wear masks all day long, which is why the lockdown is important.
- 11235813213455 6y ago
  on the other hand, lockdowns have reduced CO2 emissions in significant levels The solution is not rooms with air-filtration-conditioning or whatever, there are natural processes for that, the long term solution I see is just a reduced economic activity like during lockdowns, focused on essential sectors (so not luxury, entertainment, ..)
  - 6y ago
trekrich 6y ago
maybe i should stop eating beef now!
nudq 6y ago
I know you hate this kind of logic. But... If rising CO2 levels trigger cognitive impairment, you should be wary of everything else you think is triggered by rising CO2 levels. Because you, and all scientists, and all politicians, and Greta: You're cognitively impaired.
downerending 6y ago
TLDR: They seem to be talking about global levels over time and also mention that indoor levels can be higher, depending on how well air is exchanged with outdoor air. Probably good to be thinking about the latter, and in my well-insulated place, I often leave some windows cracked to help with this. Over periods of centuries, presumably evolution would ameliorate most or all of the problem with global changes.
- empath75 6y ago
  "evolution would ameliorate most or all of the problem" is a funny way of saying that "a lot of people are going to die younger (or have fewer children) because of this". That's the only way evolution works.
  - downerending 6y ago
    It doesn't need to be a lot younger or a lot fewer. The effect will almost certainly be virtually undetectable, especially when compared to many other evolutionary forces (e.g., diet, particulates in air, lack of exercise, social policies, etc.). If you want to improve global quality of life, CO2 levels are almost certainly not the right place to start.
  - throwaway3999 6y ago
    Natural selection is only a subset of all evolutionary processes, which are much broader than that.
- konschubert 6y ago
  CO2 levels are rising far quicker than any possible evolutionary response.
non-entity 6y ago
I feel like my cognitive ability has dwindles the past few years and while there are for sure much bigger factors playing into that, I wonder how much these environmental factors are a part of it.
- bpodgursky 6y ago
  Rising atmospheric CO2 is a very real concern, and I am very concerned about the long-term mental effects of atmospheric CO2 rising into the 900+ range. But short-term, the effects of any rise from 350 to 400ppm outdoors is going to be vastly dwarfed by indoor factors (in some poorly ventilated buildings like old schools, PPM can rise to 2000+). It's far more likely that what you encountered was due to poor ventilation than due to overall global CO2 rise.
ck2 6y ago
given the current demonstration of half the population's response to a worldwide-pandemic, there is going to be zero done about CO2 levels or climate-change in general, people are just going to watch the atmosphere boil off over centuries while the 1% move higher into their penthouses and crank the a/c
mlvljr 6y ago
Is the model on par with what https://news.ycombinator.com/item?id=23101077 https://news.ycombinator.com/item?id=23101077 discusses in terms of quality, though?
KingMachiavelli 6y ago
I see a lot of people wanting to monitor CO2 levels. But what's the cheapest remediation option for an individual if the outside air is also pretty bad whether other pollution or just high CO2? The questions I have are: is it more effective to scrub the CO2 or just to increase the partial oxygen pressure? What are the options for each. Given that oxygen tanks are existing medical device, I would assume that just supplementing oxygen is the easiest way to offset the CO2. Or is the CO2 harmful even in high oxygen environments? The study does mention "[Studies] like Satish et al. (2012) and Allen et al. (2016) are part of a growing body of scientific evidence pointing to CO2 as a pollutant—not just a proxy for ventilation rate—with direct detrimental impacts on the cognitive function of humans in schools and offices."
- frank2 6y ago
  >is it more effective to scrub the CO2 or just to increase the partial oxygen pressure? In all nuclear submarines (which stay submerged for months at a time) and spacecraft I know about, designers have chosen to scrub CO2. I think they have no choice but to scrub CO2 because CO2 has important effects on the body (e.g., increasing acidity of the blood) that cannot be counteracted by any concentration of O2. On subs, I think they react the CO2 with calcium hydroxide. On spacecraft, NASA has used lithium hydroxide (because lithium weighs less than calcium). The hydroxide gets used up during the mission. then NASA switched to some complicated system that does not use up a reagent.
- maxk42 6y ago
  CO2 is such a small proportion of the atmosphere that I have a hard time imagining its active mechanism for cognitive impairment is the displacement of oxygen. It seems you would have to scrub the CO2. Luckily, the easiest way to do this even in a big city is just to open a window.
- graeme 6y ago
  Our best option in a high pollution area is to live in a building that has made a good internal filtering system. I think it’s extremely difficult to setup in an individual house. However, the outside air will not be high co2. That’s equal enough worldwide. I’m in a city and it’s about 450 ppm outside. Higher than global average but still fine for ventilation. If you also measure particulates, you can get a sense of whether simply opening a window is sufficient.
learc83 6y ago
The navy has extensively studied performance in high CO2 environments on submarines, and found that it has no impact under levels much higher than you're likely to get indoors. This study found no impact on decision making at 15000 ppm https://pubmed.ncbi.nlm.nih.gov/29789085/ https://pubmed.ncbi.nlm.nih.gov/29789085/ That's 10x higher than you're likely to be exposed to in a poorly ventilated conference room.
- swsieber 6y ago
  From the study, emphasis mine: > we were unable to replicate this effect in a submariner population Please don't over-generalize paper results.
  - whatshisface 6y ago
    What's biologically different about submariners? Mostly male, I guess, but anything else?
    - dmoy 6y ago
      Physically more fit, pass certain psych screenings, etc. It's not exactly a good random sampling, they filter candidates very aggressively.
      - learc83 6y ago
        It's not a good random sample, but they were exposed to C02 levels 10x higher than what you'd be exposed to even in a poorly ventilated conference room.
        loopz 6y ago
        Were they exposed to out in the woods situations with conflicting goals and outcomes, or mainly just following routine and script?
        deleted 6y ago
bubmiw 6y ago
Icons for the left are now saying boycott tesla and other anti climate change statements. The right i highly doubt will ever support a quick transition to clean energy. Hope this doesn't turn into a fringe political issue now
- hackissimo123 6y ago
  Who is saying boycott Tesla?
  - bubmiw 6y ago
    Robert Reich and his circle https://twitter.com/RBReich/status/1260255145310339073 https://twitter.com/RBReich/status/1260255145310339073
- mleonhard 6y ago
  The Twitter post you link to says "Tell @elonmusk to close his factory until health experts say it's safe." That is not an anti-climate-change statement.
TheAceOfHearts 6y ago
I'm really sensitive to high CO2 levels, so ever since I was young I had a habit of opening all the windows in my classrooms when I arrived. I feel stuffy and uncomfortable until I get fresh air. It always bugged me that nobody else seemed to notice or care. After it was recommended here on HN, I bought this CO2 meter [0] and I've been very satisfied with my purchase. It reminds me to open the window and that has had a tremendous impact on my health. I've gotten to the point where I now keep the window slightly open at all times. I'll share an anecdote which would appear to support the hypothesis that higher CO2 levels affect cognition. I play Heroes of the Storm and my performance in the game becomes notably worse as CO2 levels rise. It's not a huge thing, but I start to make more mistakes and my decision-making gets worse. This is important because at my skill-level (top 100 to top 250 globally, depending on my activity levels) it only takes one mistake in the late-game to throw the match. I've had the CO2 meter start beeping in the middle of a match, and after opening the window I've managed to turn things around because I can think with greater clarity. [0] https://www.amazon.com/gp/product/B001PDGFR8/ https://www.amazon.com/gp/product/B001PDGFR8/
- yowlingcat 6y ago
  Wow. That's incredible. Do you notice the same difference with other tasks?
  - NotSammyHagar 6y ago
    Could it be (to the op) that your body has some different oxygen/co2 processing ability? I encourage you to get and oxygen sensor (the kind you put on your finger) that measures your bodies o2. Your description sounds like what I've been reading about people who have covid-19 and their bodies don't detect that don't have enough oxygen.
    - TheAceOfHearts 6y ago
      This response worried me so I went out to purchase a pulse oximeter yesterday. I've tried it a couple times, before and after various activities, and the number is usually at 99 or 100. The lowest number I've measured is a 97, but that was after wearing an N95 mask for an extended period of time; and I was able to quickly get that back up to 100 after taking a few deep breaths. But these measurements have all been taken while my CO2 meter showed a value of less than ~600ppm, so I'll have to run a few experiments with closed doors and windows to check if higher CO2 levels have an impact. I've also made a note to discuss this topic with my doctors, just as a precaution.
cryptica 6y ago
I wonder if that's why people seem to have gotten less intelligent over the past few years (IQ scores seem to confirm this). I thought it was because of social media but maybe high CO2 is to blame. I would never have thought that the movie Idiocracy would become reality; it seemed so ridiculously far-fetched at the time... Even with its 500 year timeframe... Now it looks like it may actually happen for real in only a few hundred years. I wonder if I watched that movie again today if it would come across more as a drama than a comedy.
thecleaner 6y ago
Given how COVID-19 situation is playing out in the world, I would say the cognitive impairment has already started.
arnejenssen 6y ago
CO2 is "food" for plants and trees. Maybe a higher CO2 level can sustain reforestation of desert areas causing an increase in CO2 absorption?
- nelaboras 6y ago
  There is no lack of CO2 for plants. Deserts have very different reasons for existing (and usually growing).
mleonhard 6y ago
Original article: https://cires.colorado.edu/news/continued-co2-emissions-will-impair-cognition https://cires.colorado.edu/news/continued-co2-emissions-will...

161 points by conse_lad 6y ago

deleted 6y ago

[deleted]

This does not appear to be a new study on the effects of CO2. It only mentions there will be more indoor co2 as a result of combustion? Scihub didn’t work for this one so I can’t be sure. I’m quite interested in this topic, and there are a small number of studies indicating the issue may be real. However, it is unclear this adds to them. IF the issue is real it is nonetheless useful to know what this study measures.

pas 6y ago
It's open access: https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2019GH000237 https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/201... It doesn't seem to be a trial, it's more like a deduction (basically model fitting) from available data.

wh-uws 6y ago

This one of those things that sounds silly but is actually very easy to test and see it can be a real issue. Tom Scott did a great video on it a while back https://youtu.be/1Nh_vxpycEA https://youtu.be/1Nh_vxpycEA Do yourself a favor and get an air quality monitor like an awair https://getawair.com/ https://getawair.com/ and monitor the levels. Making sure they are good in whatever indoor areas you spend a good amount of time in is a night and day difference cognitively.

zbrozek 6y ago
Anybody know of something similar which doesn't exfiltrate data from my home?
- detaro 6y ago
  For CO2 specifically, one offline option is the "CO2Meter RAD-0301", also available as "TFA Dostmann AirCO2ntrol Mini" and possibly other labels. They have an unofficial USB interface too: https://news.ycombinator.com/item?id=22764488 https://news.ycombinator.com/item?id=22764488
- ohm 6y ago
  IQAir AirVisual Pro works offline. It's expensive though.
- Lammy 6y ago
  Open your windows at least a few inches. Let some breeze through. Don't worry about the AQI number :)
throwquestion24 6y ago
Testing is fun. But what do you do then? Open the windows? Remove the cars from the freeway down the street?
- jaggederest 6y ago
  Anything that moves the air is fine. And yes, opening windows would be a sensible thing to do in that context. That said, I'm not sure I buy the thesis as a whole. As far as I am aware, last time this came up, the Navy has done pretty detailed tests on CO2 concentration as a result of submarine warfare and found no significant impairments up to 1200ppm.
- Arainach 6y ago
  Opening the windows is a solid choice. I keep a CO2 monitor in my office. So long as I keep the door open, levels usually stay below 800ppm, but if I close the door they can climb rapidly within an hour or two. I have a CO2 meter tied to an alarm to remind me to open the window if they get too high. I probably should have it set to 800, but I found that to trigger too often so I upped it to 1200. I use a RAD-0301, which works fine as a monitor and an alarm by itself, but which I connect to a Raspberry Pi for dashboard purposes using the code shared here: https://news.ycombinator.com/item?id=22764488 https://news.ycombinator.com/item?id=22764488
- kevingadd 6y ago
  If you have central heat/ac your thermostat might have a switch to convert it from 'auto' to 'on'. You can combine that with turning off the heat/cooling such that it's just a house/apartment-wide fan. I do that at night before going to bed to deal with poor airflow in my bedroom and according to my CO2 sensor, it works. It works correctly even if I leave it set to cool or heat, the thermostat still controls whether it's actually heating or circulating air. Likely what you have is the same.
- Lammy 6y ago
  I wish there was a freeway down the street. Then the cars would be here and gone instead of idling in our local streets for fifteen minutes waiting to merge. Here's a real-world study of before and after they tore down two exits of the Central Fwy and built the horrible Octavia Blvd that necessitated a bunch of sidewalk closures and keeps killing cyclists: https://archive.sfcta.org/sites/default/files/content/Planning/CentralOctaviaCirculationStudy/Final%20Report%20Executive%20Summary.pdf https://archive.sfcta.org/sites/default/files/content/Planni...
xoa 6y ago
I don't know about the awair specifically, but it's worth being cautious about cheap air quality monitors. There seems to be little good standardized testing of them, and sometimes even major brands can have abysmal accuracy. See for example the EPA study "Evaluation of Emerging Air Sensor Performance" [1], some of them have very low or even zero correlation with reference monitors. It'd be nice to see some more uniform independent lab testing and marking standards there, or maybe there already are? I've rarely been able to find comprehensive evaluations however. At least it does look like the EPA is looking at them more, last year there was a very interesting webinar overview [2] of research being done on them. There are plenty of fully dumb plain monitors too, but since you picked a smart IOT one I'd personally really want to make sure it'd work LAN-only and supported a wide array of integrations. From a quick glance it's not clear the Awair does that, and it does not have HomeKit support for example. ---- 1: https://www.epa.gov/air-sensor-toolbox/evaluation-emerging-air-sensor-performance https://www.epa.gov/air-sensor-toolbox/evaluation-emerging-a... 2: https://www.epa.gov/research-states/low-cost-air-quality-sensors-webinar-archive https://www.epa.gov/research-states/low-cost-air-quality-sen...
jack12 6y ago
Anyone getting an air quality monitor specifically because of an interest in CO2 needs to be a bit wary, a lot of them claim to have a CO2 sensor but are actually just predicting CO2 levels based on other sensors designed to measure human occupancy. CO2 sensors are/were very popular for HVAC systems to use as a proxy reading of human occupancy levels and general air quality to meet air quality requirements. Now more modern (cheaper) air quality sensors are available which measure a mix of VOCs exhaled by people instead of CO2 but have an output mode that emulates the reading from a CO2 sensor at a similar occupancy level so that HVAC systems wouldn't have to redesign their control systems / formulas, usually marketed as "equivalent CO2" (or eCO2) readings. Because they're called eCO2 sensors while being cheaper and lower power than real CO2 sensors, many air quality monitors have been using them and then surfacing their readings as "CO2 levels" under the mistaken belief that they can use the sensor to measure CO2. But it won't measure environmental CO2 at all, just predict the amount of CO2 the humans in a room would typically generate. Which is all you need for air quality monitoring, but just be aware you're not actually measuring CO2 if that's what you're curious about. There are monitors with real CO2 sensors, but you'll want to look for a teardown to see what sensor is actually being used before you purchase. The Awair 2 seems to have a real NDIR CO2 sensor (Telaire T6703), for example: https://wiki.liutyi.info/display/CO2/Awair+2+inside#Awair2inside-CO2Sensor:AmphenolTelaireT6703-5K https://wiki.liutyi.info/display/CO2/Awair+2+inside#Awair2in...
totetsu 6y ago
Kurtis Baute's full experiment from Tom's video was very interesting. He tried to seal himself in a green house with plants to generate oxygen for a few days. https://youtu.be/PoKvPkwP4mM https://youtu.be/PoKvPkwP4mM
throwaway9d0291 6y ago
If people want a more flexible, less crazy expensive option, it's fairly straightforward to build a WiFi-connected sensor with an ESP32 devkit [0], an off-the-shelf sensor like the SCD30 [1] and ESPHome [2]. This is simple to assemble, will give you fairly good, repeatable readings, auto-calibration that performs pretty well and an open-source platform with full access to your data rather than a proprietary cloud application. Full cost should be ~$70, I'd expect assembly and flashing to take ~1h the first time. The most complicated thing you'll have to do from an electronics standpoint is solder on the pin header to the sensor, other than that it's just jumper wires and flashing over USB. No need for adding resistors or capacitors or anything like that. If you're not comfortable with soldering, I _think_ the evaluation kit for the SCD30 [3] comes with pre-assembled headers. There's also a third-party variant [4] that comes with a cable header you can break out [5]. I strongly recommend that you use the SCD30. I've tested a variety of sensor components from a variety of manufacturers and the SCD30 was by far the best performing. Other sensors have problems with auto-calibration in a residential environment so either give nonsense readings or drift without periodic manual calibration. However if you want something _really_ cheap, you can replace the SCD30 with the ~$20 MH-Z19 and the total price will be ~$30. The auto-calibration on these is utterly terrible however, so you'll need to manually calibrate it with fresh air every couple of months to compensate for drift. And as others have warned, beware of retail products. A lot of them have fake "CO2" or "eCO2" sensors that don't measure CO2 but try to guess it based on other measurements. These are completely useless and are not at all indicative of actual CO2 levels. [0]: Purchase: https://octopart.com/esp32-devkitc-32d-espressif+systems-92405929 https://octopart.com/esp32-devkitc-32d-espressif+systems-924..., info: https://www.espressif.com/en/products/devkits/esp32-devkitc/overview https://www.espressif.com/en/products/devkits/esp32-devkitc/... [1]: Purchase: https://octopart.com/scd30-sensirion-89692236?r=sp https://octopart.com/scd30-sensirion-89692236?r=sp, info: https://www.sensirion.com/en/environmental-sensors/carbon-dioxide-sensors/carbon-dioxide-sensors-co2/ https://www.sensirion.com/en/environmental-sensors/carbon-di... [2]: https://esphome.io/ https://esphome.io/ [3]: https://octopart.com/sek-scd30-sensor-sensirion-101025983?r=sp https://octopart.com/sek-scd30-sensor-sensirion-101025983?r=... [4]: https://www.seeedstudio.com/Grove-CO2-Temperature-Humidity-Sensor-SCD30-p-2911.html https://www.seeedstudio.com/Grove-CO2-Temperature-Humidity-S... [5]: https://www.seeedstudio.com/Grove-4-pin-Female-Jumper-to-Grove-4-pin-Conversion-Cable-5-PCs-per-PAck.html https://www.seeedstudio.com/Grove-4-pin-Female-Jumper-to-Gro...

inamberclad 6y ago

Finally, a good explanation for the state of the world! On a realistic note, this is a cause for concern for astronauts on the ISS. They experience chronic, significantly elevated ppCO2 levels (4 torr, vs 0.3 torr at sea level), which cases headaches and fatigue, and possibly what's known as the "space stupids," where very high-key, detail oriented people start messing up checklist items and don't perform nearly as well as they should.

Tade0 6y ago
I was wondering why remote work is sometimes so difficult for me, even though I've been doing it for years. Turns out I needed to let in some fresh air more often. Getting to 1000ppm of CO2 is remarkably easy in a room with 25 cubic metres of volume.
- realharo 6y ago
  You can buy a cheap sensor, like the MH-Z19B, connect it to a Raspberry Pi Zero W (or just about anything else), and set a reminder to open the windows once the value rises above some threshold. Or just buy a finished product for this somewhere I guess.
  - hckr_news 6y ago
    Interesting thanks for the heads up

balnaphone 6y ago

From wearing COVID-19 masks? https://jamanetwork.com/journals/jama/fullarticle/2764955 https://jamanetwork.com/journals/jama/fullarticle/2764955 Quote: > Oxygen concentration inhaled by healthy subjects wearing a surgical mask covering an N95 respirator decreases to about 17%, and the concentration of carbon dioxide increases to about 1.2% - 3% in a short period of light work (2-3). Although participants did not show any obvious changes in physical function and did not have any discomfort ratings, the average carbon dioxide concentration inhaled was far higher than the limit of 0.1% of indoor carbon dioxide concentration in many countries. With prolonged mask wearing, untoward reactions may gradually appear. In another long-term study, after wearing an N95 mask for 12 hours the CO2 concentration of subjects increased to 41.0 mmHg, far higher than the baseline value of 32.4mm Hg at the beginning of the test (4). The subjects mainly reported headache, dizziness, feeling tired and communication obstacles. In real life, the situations and time of wearing masks are much longer than the above experimental research settings.

Reason077 6y ago
That's for an N95 respirator combined with a surgical mask. Most of us are just wearing surgical-type masks, and I doubt they make any difference to oxygen levels. (If they did, I'd be very worried about surgeons!)
empath75 6y ago
You can take the mask off for a while if you're starting to get uncomfortable, but yes, it's probabaly not good to wear masks all day long, which is why the lockdown is important.
11235813213455 6y ago
on the other hand, lockdowns have reduced CO2 emissions in significant levels The solution is not rooms with air-filtration-conditioning or whatever, there are natural processes for that, the long term solution I see is just a reduced economic activity like during lockdowns, focused on essential sectors (so not luxury, entertainment, ..)
- 6y ago

trekrich 6y ago

maybe i should stop eating beef now!

nudq 6y ago

I know you hate this kind of logic. But... If rising CO2 levels trigger cognitive impairment, you should be wary of everything else you think is triggered by rising CO2 levels. Because you, and all scientists, and all politicians, and Greta: You're cognitively impaired.

downerending 6y ago

TLDR: They seem to be talking about global levels over time and also mention that indoor levels can be higher, depending on how well air is exchanged with outdoor air. Probably good to be thinking about the latter, and in my well-insulated place, I often leave some windows cracked to help with this. Over periods of centuries, presumably evolution would ameliorate most or all of the problem with global changes.

empath75 6y ago
"evolution would ameliorate most or all of the problem" is a funny way of saying that "a lot of people are going to die younger (or have fewer children) because of this". That's the only way evolution works.
- downerending 6y ago
  It doesn't need to be a lot younger or a lot fewer. The effect will almost certainly be virtually undetectable, especially when compared to many other evolutionary forces (e.g., diet, particulates in air, lack of exercise, social policies, etc.). If you want to improve global quality of life, CO2 levels are almost certainly not the right place to start.
- throwaway3999 6y ago
  Natural selection is only a subset of all evolutionary processes, which are much broader than that.
konschubert 6y ago
CO2 levels are rising far quicker than any possible evolutionary response.

non-entity 6y ago

I feel like my cognitive ability has dwindles the past few years and while there are for sure much bigger factors playing into that, I wonder how much these environmental factors are a part of it.

bpodgursky 6y ago
Rising atmospheric CO2 is a very real concern, and I am very concerned about the long-term mental effects of atmospheric CO2 rising into the 900+ range. But short-term, the effects of any rise from 350 to 400ppm outdoors is going to be vastly dwarfed by indoor factors (in some poorly ventilated buildings like old schools, PPM can rise to 2000+). It's far more likely that what you encountered was due to poor ventilation than due to overall global CO2 rise.

ck2 6y ago

given the current demonstration of half the population's response to a worldwide-pandemic, there is going to be zero done about CO2 levels or climate-change in general, people are just going to watch the atmosphere boil off over centuries while the 1% move higher into their penthouses and crank the a/c

mlvljr 6y ago

Is the model on par with what https://news.ycombinator.com/item?id=23101077 https://news.ycombinator.com/item?id=23101077 discusses in terms of quality, though?

KingMachiavelli 6y ago

I see a lot of people wanting to monitor CO2 levels. But what's the cheapest remediation option for an individual if the outside air is also pretty bad whether other pollution or just high CO2? The questions I have are: is it more effective to scrub the CO2 or just to increase the partial oxygen pressure? What are the options for each. Given that oxygen tanks are existing medical device, I would assume that just supplementing oxygen is the easiest way to offset the CO2. Or is the CO2 harmful even in high oxygen environments? The study does mention "[Studies] like Satish et al. (2012) and Allen et al. (2016) are part of a growing body of scientific evidence pointing to CO2 as a pollutant—not just a proxy for ventilation rate—with direct detrimental impacts on the cognitive function of humans in schools and offices."

frank2 6y ago
>is it more effective to scrub the CO2 or just to increase the partial oxygen pressure? In all nuclear submarines (which stay submerged for months at a time) and spacecraft I know about, designers have chosen to scrub CO2. I think they have no choice but to scrub CO2 because CO2 has important effects on the body (e.g., increasing acidity of the blood) that cannot be counteracted by any concentration of O2. On subs, I think they react the CO2 with calcium hydroxide. On spacecraft, NASA has used lithium hydroxide (because lithium weighs less than calcium). The hydroxide gets used up during the mission. then NASA switched to some complicated system that does not use up a reagent.
maxk42 6y ago
CO2 is such a small proportion of the atmosphere that I have a hard time imagining its active mechanism for cognitive impairment is the displacement of oxygen. It seems you would have to scrub the CO2. Luckily, the easiest way to do this even in a big city is just to open a window.
graeme 6y ago
Our best option in a high pollution area is to live in a building that has made a good internal filtering system. I think it’s extremely difficult to setup in an individual house. However, the outside air will not be high co2. That’s equal enough worldwide. I’m in a city and it’s about 450 ppm outside. Higher than global average but still fine for ventilation. If you also measure particulates, you can get a sense of whether simply opening a window is sufficient.

learc83 6y ago

The navy has extensively studied performance in high CO2 environments on submarines, and found that it has no impact under levels much higher than you're likely to get indoors. This study found no impact on decision making at 15000 ppm https://pubmed.ncbi.nlm.nih.gov/29789085/ https://pubmed.ncbi.nlm.nih.gov/29789085/ That's 10x higher than you're likely to be exposed to in a poorly ventilated conference room.

swsieber 6y ago
From the study, emphasis mine: > we were unable to replicate this effect in a submariner population Please don't over-generalize paper results.
- whatshisface 6y ago
  What's biologically different about submariners? Mostly male, I guess, but anything else?
  - dmoy 6y ago
    Physically more fit, pass certain psych screenings, etc. It's not exactly a good random sampling, they filter candidates very aggressively.
    - learc83 6y ago
      It's not a good random sample, but they were exposed to C02 levels 10x higher than what you'd be exposed to even in a poorly ventilated conference room.
      - loopz 6y ago
        Were they exposed to out in the woods situations with conflicting goals and outcomes, or mainly just following routine and script?
        deleted 6y ago

bubmiw 6y ago

Icons for the left are now saying boycott tesla and other anti climate change statements. The right i highly doubt will ever support a quick transition to clean energy. Hope this doesn't turn into a fringe political issue now

hackissimo123 6y ago
Who is saying boycott Tesla?
- bubmiw 6y ago
  Robert Reich and his circle https://twitter.com/RBReich/status/1260255145310339073 https://twitter.com/RBReich/status/1260255145310339073
mleonhard 6y ago
The Twitter post you link to says "Tell @elonmusk to close his factory until health experts say it's safe." That is not an anti-climate-change statement.

TheAceOfHearts 6y ago

I'm really sensitive to high CO2 levels, so ever since I was young I had a habit of opening all the windows in my classrooms when I arrived. I feel stuffy and uncomfortable until I get fresh air. It always bugged me that nobody else seemed to notice or care. After it was recommended here on HN, I bought this CO2 meter [0] and I've been very satisfied with my purchase. It reminds me to open the window and that has had a tremendous impact on my health. I've gotten to the point where I now keep the window slightly open at all times. I'll share an anecdote which would appear to support the hypothesis that higher CO2 levels affect cognition. I play Heroes of the Storm and my performance in the game becomes notably worse as CO2 levels rise. It's not a huge thing, but I start to make more mistakes and my decision-making gets worse. This is important because at my skill-level (top 100 to top 250 globally, depending on my activity levels) it only takes one mistake in the late-game to throw the match. I've had the CO2 meter start beeping in the middle of a match, and after opening the window I've managed to turn things around because I can think with greater clarity. [0] https://www.amazon.com/gp/product/B001PDGFR8/ https://www.amazon.com/gp/product/B001PDGFR8/

yowlingcat 6y ago
Wow. That's incredible. Do you notice the same difference with other tasks?
- NotSammyHagar 6y ago
  Could it be (to the op) that your body has some different oxygen/co2 processing ability? I encourage you to get and oxygen sensor (the kind you put on your finger) that measures your bodies o2. Your description sounds like what I've been reading about people who have covid-19 and their bodies don't detect that don't have enough oxygen.
  - TheAceOfHearts 6y ago
    This response worried me so I went out to purchase a pulse oximeter yesterday. I've tried it a couple times, before and after various activities, and the number is usually at 99 or 100. The lowest number I've measured is a 97, but that was after wearing an N95 mask for an extended period of time; and I was able to quickly get that back up to 100 after taking a few deep breaths. But these measurements have all been taken while my CO2 meter showed a value of less than ~600ppm, so I'll have to run a few experiments with closed doors and windows to check if higher CO2 levels have an impact. I've also made a note to discuss this topic with my doctors, just as a precaution.

cryptica 6y ago

I wonder if that's why people seem to have gotten less intelligent over the past few years (IQ scores seem to confirm this). I thought it was because of social media but maybe high CO2 is to blame. I would never have thought that the movie Idiocracy would become reality; it seemed so ridiculously far-fetched at the time... Even with its 500 year timeframe... Now it looks like it may actually happen for real in only a few hundred years. I wonder if I watched that movie again today if it would come across more as a drama than a comedy.

thecleaner 6y ago

Given how COVID-19 situation is playing out in the world, I would say the cognitive impairment has already started.

arnejenssen 6y ago

CO2 is "food" for plants and trees. Maybe a higher CO2 level can sustain reforestation of desert areas causing an increase in CO2 absorption?

nelaboras 6y ago
There is no lack of CO2 for plants. Deserts have very different reasons for existing (and usually growing).

mleonhard 6y ago

Original article: https://cires.colorado.edu/news/continued-co2-emissions-will-impair-cognition https://cires.colorado.edu/news/continued-co2-emissions-will...