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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

#171

Post by amelius »

kingkawn wrote: post #165
microtonal wrote: post #115

Earlier quoted context omitted.

I think the issue is that the common tech requires sensors in an air-chamber. E.g. NDIR works by firing IR at a frequency that is absorbed by CO2. A sensor on the other side either measures the amount of IR light that got through (optical NDIR) or pressure/sound waves (photoacoustic NDIR). I guess that it's hard to use any existing sensors, because they are relatively large and probably water could easily get into th…

Mesh with the other Apple/et al devices in the room to take multiple samples and aggregate the results for an overall picture of the ambient co2

What if a movie theater puts an Apple CO2 meter next to an air inlet? Everybody will think the air is safe.

Re: The bottleneck might be the air in the room

#172

Post by em-bee »

hanspagel wrote: post #76

Not gonna happen in Germany. I don’t think I‘ve ever seen a windowless room here and it’s common to open all windows at once for a few minutes, just to replace as much air as possible: Stoßlüften.

when i read the article i thought that maybe this is where german ingenuity comes from.

but then germany hasn't been doing so well lately, and people who do most of their work outside should also be doing better...

Re: The bottleneck might be the air in the room

#176

Post by dgellow »

noja wrote: post #145
londons_explore wrote: post #139

Earlier quoted context omitted.

Oxygen sensors used in car catalyst systems use a different effect based on electrochemistry. I see no reason that couldn't be minuaritized to grain-of-sand size. The question is if oxygen levels are as good an indicator as CO2 levels... I suspect not.

I don’t think we actually care about co2 levels. I think we use them as a proxy for o2 levels (same as our bodies do). So your idea would be great.

What makes you think that?

Re: The bottleneck might be the air in the room

#177

Post by XorNot »

Lwerewolf wrote: post #162
londons_explore wrote: post #139

Earlier quoted context omitted.

Oxygen sensors used in car catalyst systems use a different effect based on electrochemistry. I see no reason that couldn't be minuaritized to grain-of-sand size. The question is if oxygen levels are as good an indicator as CO2 levels... I suspect not.

The ones in cars need to be heated up quite a bit in order to work, and you still need reference air. Otherwise, I'm pretty sure that CO2 isn't a problem but rather an indication of a lack of oxygen in the first place, so it technically could work... just not if you're measuring the environment itself.

This is in theory not a problem: getting an oxygen sensor to 700 degrees if it's a tiny spec on a chip is not necessarily hard or would even require a lot of power.

But...oxygen concentration is essentially indepedent of CO2. We measure CO2 at part per million levels, whereas O2 is 20% of the air.

(In that context CO2 is surprisingly toxic given that 1000 ppm can impair mental acuity).

Re: The bottleneck might be the air in the room

#178

Post by mrob »

Gigachad wrote: post #40
throw-the-towel wrote: post #25

Earlier quoted context omitted.

Use an air purifier, wear a respirator outside if you live in a polluted place.

Air purifier is good for PM2.5 and other microscopic pollutants but it doesn’t do that much for dust unless it’s particularly light dust and very close to the purifier. Dust is much more likely to just settle on the ground and be kicked back up than it is to move all the way to the purifier to get stuck in the filter.

I have an air purifier with built in particulate sensor. It doesn't provide numbers, but has a multi-color LED indicator to report PM2.5 level as good/mediocre/bad/terrible. Running a vacuum cleaner that supposedly has a good filter consistently increases the reported PM2.5 level from the first band to the second. The air purifier (or faster/cheaper depending on the weather, just open some windows) can bring it back down again.

Re: The bottleneck might be the air in the room

#179

Post by dgellow »

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.

Worst case people open windows without effect, no?

Re: The bottleneck might be the air in the room

#180

Post by XorNot »

noja wrote: post #145
londons_explore wrote: post #139

Earlier quoted context omitted.

Oxygen sensors used in car catalyst systems use a different effect based on electrochemistry. I see no reason that couldn't be minuaritized to grain-of-sand size. The question is if oxygen levels are as good an indicator as CO2 levels... I suspect not.

I don’t think we actually care about co2 levels. I think we use them as a proxy for o2 levels (same as our bodies do). So your idea would be great.

This is extremely wrong: CO2 impairment kicks in around 1000 ppm[1] possibly lower.

You can hit this breathing by yourself in an unventilated 3x3m room (literally measured in my house).

1 https://pmc.ncbi.nlm.nih.gov/articles/PMC4892924/

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