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First clean water, now clean air

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Re: First clean water, now clean air

#91

Post by radlad »

bsenftner wrote: post #23
isp wrote: post #4

Earlier quoted context omitted.

> So if we want to do something, I think the first step is really to get visibility to the problem A sensible first step would be to very visibly display CO₂ monitors in buildings (e.g., throughout office buildings, schools, etc) Once the CO₂ levels become visible, this in itself creates an incentive to improve. Related from UK (2021): "All schools to receive carbon dioxide monitors" - https://www.gov.uk/government/n…

In Japan, it is common to see CO₂ monitor displays outside contained meeting spaces, such as theaters. My wife purchased an Aronet CO₂ monitor, and I took it with me on a business trip last week. The CO₂ while on the flight was in the 3000's range. The CO₂ at my client's office was in the mid 2000's range, as well as the hotel. Opening the hotel window the allowed 2 inches reduces CO₂ to the 600 range in 10 minutes,…

> The CO₂ while on the flight was in the 3000's range.

I always assumed they intentionally messed with oxygen in the cabin to "relax" travelers.

Anecdotally, I have often experienced a sedative effect on airplanes that I do not ever experience in land vehicles.

Re: First clean water, now clean air

#92

Post by prmoustache »

ct0 wrote: post #28
LeonM wrote: post #9

Earlier quoted context omitted.

I don't understand why you are being downvoted, you raise a good point. Based on some HN comment from a while ago I invested in a CO2 meter (they are still quite expensive for some reason). And I share the same experience, CO2 levels can raise rapidly indoors, but simply turning on ventilation or opening a window very quickly lowers CO2 contents. Using the meter I found CO2 levels in my bedroom can become quite high…

I'm starting to think that having a better night's rest while sleeping in a tent is not from the ground you sleep on, but the fresh air you've had all night.

you want to sleep below a tarp then, not in a tent.

Re: First clean water, now clean air

#93

Post by JBorrow »

steviedotboston wrote: post #90

I don't think the clear water and clear air analogy works very well. They seem to be very different cases. Keeping clean and dirty water separate is trivial and requires no more advanced technology than plumbing. Keeping clean and "dirty" air separate is impossible. We will always breathe air that includes pathogens. That isn't to say there should be efforts to improve air quality, but I think a lot of times analogie…

"Cleanliness and modern plumbing" include massive water treatment facilities, digging up every street, laying billions of miles of pipe.

Re: First clean water, now clean air

#94

Post by GloriousKoji »

anonyfox wrote: post #38
LeonM wrote: post #9

Earlier quoted context omitted.

I don't understand why you are being downvoted, you raise a good point. Based on some HN comment from a while ago I invested in a CO2 meter (they are still quite expensive for some reason). And I share the same experience, CO2 levels can raise rapidly indoors, but simply turning on ventilation or opening a window very quickly lowers CO2 contents. Using the meter I found CO2 levels in my bedroom can become quite high…

… and people make joke about us Germans need to do „stosslüften“ (opening all windows in parallel to get fresh air in fast). also, are there really people that can (or even prefer!) to sleep with closed windows?! Only with AC blasting, right?

It's way too loud if I sleep with the windows open.

Re: First clean water, now clean air

#95

Post by tesseract »

radlad wrote: post #91
bsenftner wrote: post #23

Earlier quoted context omitted.

In Japan, it is common to see CO₂ monitor displays outside contained meeting spaces, such as theaters. My wife purchased an Aronet CO₂ monitor, and I took it with me on a business trip last week. The CO₂ while on the flight was in the 3000's range. The CO₂ at my client's office was in the mid 2000's range, as well as the hotel. Opening the hotel window the allowed 2 inches reduces CO₂ to the 600 range in 10 minutes,…

> The CO₂ while on the flight was in the 3000's range. I always assumed they intentionally messed with oxygen in the cabin to "relax" travelers. Anecdotally, I have often experienced a sedative effect on airplanes that I do not ever experience in land vehicles.

Well, there's less of it, since typical airliner cabin pressure is equivalent to being at 8000ft altitude or so. Do you typically spend long durations driving in the mountains?

Re: First clean water, now clean air

#96

Post by GloriousKoji »

mypastself wrote: post #3
sergioisidoro wrote: post #2

I bought a CO2 monitor, and although the effects of CO2 in cognition and energy levels are debatable[1], it shocked me and raised awareness to how poor my indoor ventilation is. We live in a small apartment, and just being 30 min with 2 people in the room raises the CO2 ppm from 400 to >1000. Opening a window quickly lowers it. Never-mind doing some light activity like yoga or similar. So if we want to do something,…

Not to hijack your thread, but I wonder if anyone here’s built their own Raspberry/Arduino CO2 monitor? Which (reliable) sensors did you use? Did you find it more affordable than purchasing a monitor, especially if you already had unused microcontrollers lying around the house?

The microcontroller is the cheapest part! The good sensors that you want to use are in the $45 range. Look for "True" CO2 sensor that use some sort of optical technique to measure CO2. A lot of the really cheap CO2 monitors just measure VOC with some kind of metal element and approximate CO2. I like Sensirion SCD30 or SCD40.

Re: First clean water, now clean air

#97

Post by weaksauce »

radlad wrote: post #91
bsenftner wrote: post #23

Earlier quoted context omitted.

In Japan, it is common to see CO₂ monitor displays outside contained meeting spaces, such as theaters. My wife purchased an Aronet CO₂ monitor, and I took it with me on a business trip last week. The CO₂ while on the flight was in the 3000's range. The CO₂ at my client's office was in the mid 2000's range, as well as the hotel. Opening the hotel window the allowed 2 inches reduces CO₂ to the 600 range in 10 minutes,…

> The CO₂ while on the flight was in the 3000's range. I always assumed they intentionally messed with oxygen in the cabin to "relax" travelers. Anecdotally, I have often experienced a sedative effect on airplanes that I do not ever experience in land vehicles.

the oxygen levels in airplanes are not high because they only pressurize the cabin to be about a 7000' pressurization. that's roughly equivalent to a lot of mountain town altitudes... think flagstaff.

Re: First clean water, now clean air

#98

Post by Rebelgecko »

clairity wrote: post #86
fatuna wrote: post #79

Earlier quoted context omitted.

Do you have any sources on this? I'm keen to know more, but googling results in either very dry researchpapers or ads on either co2 meters or air purifiers.

here's a USDA fact sheet summarizing the effects of CO₂ at different concentrations that's more easily digestible than an academic paper: https://www.fsis.usda.gov/sites/default/files/media_file/202...

There are a number of studies that have found that CO2 levels lower than the OSHA limit of 5,000 ppm can still cause issues like slight cognitive impairment and worse sleep (however there's also a few studies that have found no or minimal impact of levels below 5,000ppm)

Re: First clean water, now clean air

#99

Post by Rebelgecko »

Lukas_Skywalker wrote: post #6
mypastself wrote: post #3

Earlier quoted context omitted.

Not to hijack your thread, but I wonder if anyone here’s built their own Raspberry/Arduino CO2 monitor? Which (reliable) sensors did you use? Did you find it more affordable than purchasing a monitor, especially if you already had unused microcontrollers lying around the house?

I built one based on the AirGradient DIY sensor [1]. It is open source, and you can order PCBs or build them yourself. It is also compatible with ESPHome. It uses the "Senseair S8" CO2 sensor, which costs a bit (25-30$), but (according to AirGradient) has a very high quality. [1]: https://www.airgradient.com/open-airgradient/instructions/di...

Seconding this recommendation. I was surprised how easy and cheap it was to order my own tweaked PCBs. Airgradient has also done a lot of testing to determine which components work well and what their different failure modes are.

Depending on how many you build at a time, you can source all the parts for maybe $40-$60. Assembly is straightforward as long as you're comfortable with through-hole soldering (and if not, this is a great chance to learn). The design is also modular enough that it's easy to skip on things like the thermometer or particulate matter sensor if you're so inclined.

Re: First clean water, now clean air

#100

Post by cultureswitch »

anonyfox wrote: post #38
LeonM wrote: post #9

Earlier quoted context omitted.

I don't understand why you are being downvoted, you raise a good point. Based on some HN comment from a while ago I invested in a CO2 meter (they are still quite expensive for some reason). And I share the same experience, CO2 levels can raise rapidly indoors, but simply turning on ventilation or opening a window very quickly lowers CO2 contents. Using the meter I found CO2 levels in my bedroom can become quite high…

… and people make joke about us Germans need to do „stosslüften“ (opening all windows in parallel to get fresh air in fast). also, are there really people that can (or even prefer!) to sleep with closed windows?! Only with AC blasting, right?

I can't sleep with either AC, simple ventilation or windows open. Too much noise. In rural environments too, just a single cricket is capable of keeping me awake.

Sometimes in very hot weather I do leave the windows open at night but it's due to heat, not air quality.

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