This is a fascinating example of best practices versus actual application. A bit like the joke that every software developer knows how that woman who is crying as the guy puts all of the blocks through the square hole feels when watching how users actually interact with an interface. I believe that Air Quality Engineer is an actual title and these people are right that if you want your house to breathe, you should give it a pair of lungs, which is to say install a heat exchange and be pulling in fresh air that you also filter at a constant rate and also aggressively seal off your crawl space so that any exhaust fans from the house aren't drying up any bad vapors in case their demand is greater than the heat exchange, etc. These are all perfectly reasonable, but the problem is that in the real world, somebody in such a house will tightly close up a bedroom and then burn a bunch of incense in it or paint a bunch of Warhammer miniatures or use a ton of nail polish or whatever, and while the rest of the house is breathing fine, that one room will be a gas chamber. Old houses solve this problem by just not being able to be converted into gas chambers. Really old houses like the ones in Scotland where the entire roof is made out of heather and is permeable to smoke to such an extent that you don't even need a chimney are one of the most aggressive examples. Or look at traditional skin-covered dwellings where there is always a smoke hole in the top and a flap left open for intake, even on the Great Plains in freezing temperatures and high winds.
Yea it always feels like hubris to me when we decide that we've absolutely, positively figured it out and we should ignore millennia of tacit knowledge and just seal ourselves in plastic bags WHAT ARE YOU A SCIENCE DENIER?!
People in open offices excrete many gases and particles, which are difficult to measure. It is not well known which excreted gases and particle cause drowsiness and headaches. CO2 is easy to measure, so CO2 is often chosen as a somewhat random measurement of air quality, which has some correlation with drowsiness. CO2 is actually supposed to be quite healthy, so we would benefit from much more CO2 in the air.
What's the root of your comment about LDL only being bad if you look at it sideways? I thought there were quite large epidemiological studies showing a strong correlation between high LDL cholesterol (or maybe high LDL:HDL ratio) and heart disease? (I'd love this not to be the case, btw, as I've had "high LDL" since my first health tests, 30+ years ago, and I'm not dead yet...)
Basically, there doesn't seem to be any evidence for the lipid-heart hypothesis. There is just as much evidence that LOW ldl is associated with Bad Things (tm), e.g. all-cause mortality. But of course this evidence is also epiodemiological, aka very weak. Maybe useful for hypothesis generation, but not enough to prove anything.
The big one is; CVD in the modern sense was nearly unknown around 1900. They actually had an "epidemic" around that time. Yet people were eating tons of saturated fat like beef & butter back then. Almost nobody in the US was eating olive oil back then, and PUFAs had just recently been invented. Crisco was yet to enter the market.
How do we square that with the LDL->CVD hypothesis? It just doesn't.
And the mechanisms they claim just don't hold up either. There are so many holes, the holes are structural and always have been.
Personally, I subscribe to Tucker's "LDL is only bad if it carries oxidized linoleic acid" hypothesis. I did a test for that specifically, and my count was extremely low despite having very high LDL (due to a high-fat diet).
Thanks for posting. I recently was having similar issues of feeling stuffy in my office. I bought an air quality monitor and nearly every day I go above 1,000ppm CO2 in the afternoons. My monitor thinks >1,000ppm is instant death, so it beeps incessantly. I’ll have to look more into this!
Hmm, it is known that humans breathe out volatile organic compounds (VOCs) and I think that's actually how we detect stale air (I don't think humans can detect CO2 directly which is why coal miners needed canaries?). So it could be those compounds that cause the headache. Then why does the correlation between CO2 and VOCs break down in your old bedroom? Maybe the large VOC molecules get stuck in the stone walls or something like that?
You can't smell CO², but our lungs do detect it, and in fact we need it to breathe – you don't breathe if the CO² level in the air is too low, whether there's enough O² in it or not. Coal miners needed canaries to detect CO.
Oops, turns out I was wrong: it's the amount of CO² in the *blood* that determines how often you breathe. "[I]f the blood CO2 starts to rise, then your brain will drive you breathe more (either by increasing your breathing rate or breath size or both), and if your blood CO2 starts to fall, then your brain will cause you to breathe less so that CO2 levels rise again. All of this is happening at a completely subconscious level as you sit reading this. In most people the brain is ‘set’ to maintain a dissolved PCO2 of about 5 kilopascals (kPa) (or 0.05 ATA or 38mmHg depending on what units you prefer to use) in the arterial blood."
Since humans make CO2, CO2 levels in spaces work as proxy for air transfer with outside.
So high CO2 but no headaches probably rules out low oxygen level, since humans consume oxygen so low air transfer would reduce oxygen levels.
Instead most likely explanation is that there is something that gets discharged into air from new buildings but not (all) old buildings that causes problems unless enough air exchange with outside.
Back when i had asthma, it would go fully away when travelling to southern europe with their leaky walls.
I have nothing personal to offer, but have you read https://slatestarcodex.com/2018/08/23/carbon-dioxide-an-open-door-policy/ ?
I have not! Will check out, thanks.
This is a fascinating example of best practices versus actual application. A bit like the joke that every software developer knows how that woman who is crying as the guy puts all of the blocks through the square hole feels when watching how users actually interact with an interface. I believe that Air Quality Engineer is an actual title and these people are right that if you want your house to breathe, you should give it a pair of lungs, which is to say install a heat exchange and be pulling in fresh air that you also filter at a constant rate and also aggressively seal off your crawl space so that any exhaust fans from the house aren't drying up any bad vapors in case their demand is greater than the heat exchange, etc. These are all perfectly reasonable, but the problem is that in the real world, somebody in such a house will tightly close up a bedroom and then burn a bunch of incense in it or paint a bunch of Warhammer miniatures or use a ton of nail polish or whatever, and while the rest of the house is breathing fine, that one room will be a gas chamber. Old houses solve this problem by just not being able to be converted into gas chambers. Really old houses like the ones in Scotland where the entire roof is made out of heather and is permeable to smoke to such an extent that you don't even need a chimney are one of the most aggressive examples. Or look at traditional skin-covered dwellings where there is always a smoke hole in the top and a flap left open for intake, even on the Great Plains in freezing temperatures and high winds.
Yea it always feels like hubris to me when we decide that we've absolutely, positively figured it out and we should ignore millennia of tacit knowledge and just seal ourselves in plastic bags WHAT ARE YOU A SCIENCE DENIER?!
People in open offices excrete many gases and particles, which are difficult to measure. It is not well known which excreted gases and particle cause drowsiness and headaches. CO2 is easy to measure, so CO2 is often chosen as a somewhat random measurement of air quality, which has some correlation with drowsiness. CO2 is actually supposed to be quite healthy, so we would benefit from much more CO2 in the air.
What's the root of your comment about LDL only being bad if you look at it sideways? I thought there were quite large epidemiological studies showing a strong correlation between high LDL cholesterol (or maybe high LDL:HDL ratio) and heart disease? (I'd love this not to be the case, btw, as I've had "high LDL" since my first health tests, 30+ years ago, and I'm not dead yet...)
Basically, there doesn't seem to be any evidence for the lipid-heart hypothesis. There is just as much evidence that LOW ldl is associated with Bad Things (tm), e.g. all-cause mortality. But of course this evidence is also epiodemiological, aka very weak. Maybe useful for hypothesis generation, but not enough to prove anything.
The big one is; CVD in the modern sense was nearly unknown around 1900. They actually had an "epidemic" around that time. Yet people were eating tons of saturated fat like beef & butter back then. Almost nobody in the US was eating olive oil back then, and PUFAs had just recently been invented. Crisco was yet to enter the market.
How do we square that with the LDL->CVD hypothesis? It just doesn't.
And the mechanisms they claim just don't hold up either. There are so many holes, the holes are structural and always have been.
Personally, I subscribe to Tucker's "LDL is only bad if it carries oxidized linoleic acid" hypothesis. I did a test for that specifically, and my count was extremely low despite having very high LDL (due to a high-fat diet).
Thanks for posting. I recently was having similar issues of feeling stuffy in my office. I bought an air quality monitor and nearly every day I go above 1,000ppm CO2 in the afternoons. My monitor thinks >1,000ppm is instant death, so it beeps incessantly. I’ll have to look more into this!
Hmm, it is known that humans breathe out volatile organic compounds (VOCs) and I think that's actually how we detect stale air (I don't think humans can detect CO2 directly which is why coal miners needed canaries?). So it could be those compounds that cause the headache. Then why does the correlation between CO2 and VOCs break down in your old bedroom? Maybe the large VOC molecules get stuck in the stone walls or something like that?
You can't smell CO², but our lungs do detect it, and in fact we need it to breathe – you don't breathe if the CO² level in the air is too low, whether there's enough O² in it or not. Coal miners needed canaries to detect CO.
If that was true, divers using pure nitrogen+oxygen combo would stop breathing.
Oops, turns out I was wrong: it's the amount of CO² in the *blood* that determines how often you breathe. "[I]f the blood CO2 starts to rise, then your brain will drive you breathe more (either by increasing your breathing rate or breath size or both), and if your blood CO2 starts to fall, then your brain will cause you to breathe less so that CO2 levels rise again. All of this is happening at a completely subconscious level as you sit reading this. In most people the brain is ‘set’ to maintain a dissolved PCO2 of about 5 kilopascals (kPa) (or 0.05 ATA or 38mmHg depending on what units you prefer to use) in the arterial blood."
—https://www.divepacific.co.nz/post/carbon-dioxide-and-diving-basic-carbon-dioxide-physiology
Since humans make CO2, CO2 levels in spaces work as proxy for air transfer with outside.
So high CO2 but no headaches probably rules out low oxygen level, since humans consume oxygen so low air transfer would reduce oxygen levels.
Instead most likely explanation is that there is something that gets discharged into air from new buildings but not (all) old buildings that causes problems unless enough air exchange with outside.
Back when i had asthma, it would go fully away when travelling to southern europe with their leaky walls.
https://pubmed.ncbi.nlm.nih.gov/31667660/