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The bottleneck might be the air in the room

blog.mikebowler.ca

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Re: The bottleneck might be the air in the room

#461

Post by Gigachad »

OutOfHere wrote: post #212
Gigachad wrote: post #154

Earlier quoted context omitted.

For the purposes of indoor ventilation monitoring you can calibrate by occasionally exposing the sensor to fresh air. Either taking it outside or just the room not having people in it. The sensor will treat the lowest reading it gets as 400ppm since this is what outdoor air is. A sensor mounted in the office will get calibrated every night when the office is empty.

The outdoor CO2 is rising every year. It is not fixed at 400 ppm. The calibrations you speak of are fake. A good sensor can be expected to remain within 10% of reference for ten years.

If you want to make measuring CO2 your obsessive compulsion then sure, buy a lab grade instrument. If you want to get a practical reading of the air quality that is more than good enough, affordable, and looks nice on your bedside, the ikea one is a great option.

Re: The bottleneck might be the air in the room

#462

Post by sarchertech »

josephg wrote: post #295
throw0101a wrote: post #217

Earlier quoted context omitted.

> There are so many rooms, classrooms, movie theaters and other places with poor ventilation where you just feel dizzy, or fall asleep, not knowing it was just due to lower oxygen levels in your blood. Raising awareness is the only real solution. Not wrong, but it is perhaps worth noting that there are already standards for proper ventilation. Generally you're looking at 5–10 cfm/person (2.5-5 L/s), depending on the…

Should… Whenever I travel, I bring a CO2 meter with me. It’s amazing how often the air is bad. Often in unexpected places. My meter hit 3100 in an uber once. I didn’t even notice until I got to my hotel room and looked at the data log. It was a fresh, hot day outside. The uber had windows closed and AC on. I bet he had no idea - but he was driving with significant cognitive impairment. Takeoff and landing in planes a…

He’s not driving with significant cognitive impairment. Submarines and the ISS routinely operate at 5000 ppm. 60 years of studies and almost a century of operating submarines has shown no impairment at 5000 ppm.

Then all of the sudden Satish 2012 comes along and shows serious cognitive impairment at 1000 ppm. The only studies that have replicated this involved Satish. Studies without Satish as a coauthor fail to replicate their findings.

If you think about it for a second, the levels of impairment Satish shows don’t make sense at all. You’d expect to see differences on SAT scores of hundreds of points between test centers with good ventilation and bad. You’d expect to see massive differences between regions where AC is more or less common. Or even between seasons.

Re: The bottleneck might be the air in the room

#463

Post by mathgeek »

wongarsu wrote: post #246
mathgeek wrote: post #221

Earlier quoted context omitted.

The evolved response to CO2 is part of the human body’s ability to filter and remove CO2 via the respiratory system. AFAIK we don’t have similar capacity for Nitrogen because it’s not a primary waste product of that system.

Dissolving CO2 in water creates some carbonic acid (H2CO3) that will decompose back to water and CO2 when the CO2 concentration drops. Blood has a fair bit of water, and carbonic acid is much easier to detect than oxygen or nitrogen gas We evolved to detect CO2 because that's by far the easiest thing to detect that's still a reasonable proxy for the performance of our respiratory system

We evolved to detect CO2 because it was an evolutionary advantage over those who didn’t.

Re: The bottleneck might be the air in the room

#464

Post by XorNot »

teravor wrote: post #460
XorNot wrote: post #456

Earlier quoted context omitted.

I'm not implying permanent effects. The studies involved show a marginal reduction in cognitive reasoning on standardized tests. Which is the point: if you're in a room trying to do deep work, that's likely a problem. I suspect submarines are all over the place here: you might be exposed to higher levels routinely but you also have regular access to chemical scrubbers and decent ventilation. I'd be fascinated to know…

apparently those scrubbers are less efficient the lower the co2 is (also need to move much more air which ruins stealth). iirc submarines are routinely exposed to multiple thousands.

It does look like this has been studied: https://pubmed.ncbi.nlm.nih.gov/29789085/ and found no significant effects.

So quite possibly an adaptive response?

Re: The bottleneck might be the air in the room

#465

Post by wodenokoto »

deanc wrote: post #13

I’m not saying this isn’t a legitimate concern but this really seems to have exploded amongst the tech community as the next obsession. I see this pop up on X every few weeks. Is the concern about this really based on actual science? Is there empirical data proving people are less productive or are damaging themselves as a result of heightened CO2 levels? And I don’t mean observational epidemiology studies.

The level at which it is a concern might be skewed, but if you’ve ever sat in a room with “thick” air, trying to concentrate you know it is a real thing and just opening a window and a door for a few minutes to create a draft helps tremendously.

Re: The bottleneck might be the air in the room

#466

Post by [deleted] »

fuzzfactor wrote: post #432
prodigycorp wrote: post #197

Earlier quoted context omitted.

Your comment actually has me convinced that this isn't an issue. I've been a recirculation dude for my entire life, I literally don't drive any other way.

In the 1970's when factory A/C started to get widespread adoption in other than very expensive cars, it was common for more than one US automaker to almost standardize on a dashboard system of levers or knobs. At the extreme was "MAX" which most people didn't realize was "recirculate" unless they read the owner's manual in those cases where it was well documented. The next notch over was "NORM" which as the name impl…

[deleted]

Re: The bottleneck might be the air in the room

#469

Post by fingerlocks »

jerlam wrote: post #441
josephg wrote: post #295

Earlier quoted context omitted.

Should… Whenever I travel, I bring a CO2 meter with me. It’s amazing how often the air is bad. Often in unexpected places. My meter hit 3100 in an uber once. I didn’t even notice until I got to my hotel room and looked at the data log. It was a fresh, hot day outside. The uber had windows closed and AC on. I bet he had no idea - but he was driving with significant cognitive impairment. Takeoff and landing in planes a…

Cars have a "make the air bad" button, the recirculation button. Some people always have it on. I wonder if it's a factor in road rage.

Sounds like you need to change your cabin filter.

Re: The bottleneck might be the air in the room

#470

Post by josephg »

fingerlocks wrote: post #469
jerlam wrote: post #441

Earlier quoted context omitted.

Cars have a "make the air bad" button, the recirculation button. Some people always have it on. I wonder if it's a factor in road rage.

Sounds like you need to change your cabin filter.

Perhaps a lot of people should change their cabin filters.

Air quality should be good everywhere. But its not. You can't tell if you don't measure it.

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