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First clean water, now clean air

finmoorhouse.com

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Re: First clean water, now clean air

#111

Post by bsder »

rcme wrote: post #83
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,…

I think the first step would be to buy a second monitor, ideally from a different manufacturer, and verify that your readings are actually correct. My experience is that cheap monitors are basically random.

Precisely this.

I haven't seen anybody take any of the cheap CO2 sensors and demonstrate that they are anywhere in the range of the readings of a lab grade CO2 sensor.

Re: First clean water, now clean air

#112

Post by symlinkk »

Abekkus wrote: post #35
sbaiddn wrote: post #15

Earlier quoted context omitted.

That's why I'm not changing my very leaky and drafty windows - I don't want to live in a hermetically sealed Tupperware container. Once I install an HRV system then I'll do the windows!

Or you could save $2k on materials & labor, and put in a filtered vent fan. You only need around 15CFM per resident. Household HRVs & ERVs have suspiciously low heat efficiencies for their costs.

Are you talking about a fan that simply blows outside air in? Wouldn’t that basically fight what the HVAC is doing? AFAIK the only real solution is an ERV / HRV, and they are extremely expensive (like $10k in my area)

Re: First clean water, now clean air

#113

Post by endisneigh »

switchbak wrote: post #88
endisneigh wrote: post #54

Earlier quoted context omitted.

you're right. things have tradeoffs. the point is that most barely have central AC with vents, let alone an HRV.

Most homes don't have HRVs not only due to cost, but because homes didn't used to be tight enough to require them. We also didn't understand how important fresh air is. Many homes didn't have AC because a) it was expensive, and b) you used to not need it as much. And plenty of people can afford these things, cost is not the only consideration nor some magic word to dismiss the tech generally.

No one is dismissing anything

Re: First clean water, now clean air

#114

Post by nicenewtemp84 »

rcme wrote: post #83
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,…

I think the first step would be to buy a second monitor, ideally from a different manufacturer, and verify that your readings are actually correct. My experience is that cheap monitors are basically random.

If your reader raises it's reading as you sit in a small room, and lowers when you open a window... It's probably not at risk of being random. Inaccurate maybe, but still sensing in the correct direction.

Re: First clean water, now clean air

#115

Post by sergioisidoro »

clairity wrote: post #80
sergioisidoro wrote: post #63

Earlier quoted context omitted.

Yes they are debatable. There are cognitive performance tests that show statistically significant decline in many tasks above 1500ppm, especially on planning tasks. That's independently of the feeling of "stuffiness". If these measurable declines have a sufficient impact on our lives and productivity is the debatable part. Edit: here's one reference: "We also found effects of CO2 (a proxy for ventilation) on cognitiv…

if you look at the paper, you see no such conclusive evidence, but rather weak correlative assertions in noisy and complex environments. also notice the incentives and implicit bias of the involved. unbiased studies from the past several decades have so far shown cognitive effects require 10× that level of CO₂ to show any conclusive effects. even the pm2.5 effects attempt to make a short-term correlation, which is du…

See, they are debatable after all - we are debating them. There is data, there are some correlations that are statistically significant, and some raise even more questions — like why performance lowers at 1200ppm, but goes back up at higher concentrations in this article published on Nature in a very controlled environment - https://www.nature.com/articles/s41526-019-0071-6

I don't think this topic distracts from anything. I live in Finland, where indoor air quality is a big topic (mycotoxins and spores due to mold in old houses, burning wood in residential areas due to particulate emissions on cold days, construction codes, etc), while the country is making strides to become carbon neutral, and has one of the lowest economical inequality in the world.

But anyway, as I mentioned in the initial comment, the high CO2 just raised my attention to the bad ventilation of the house, and that includes ventilation of particulates from activities like cooking.

Re: First clean water, now clean air

#116

Post by balfirevic »

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?

Yes, that's the only way to have nice cozy temperature throughout the year. Heating will be on during large part of the year, but during the summer AC will be on. Just working gently, though, no blasting.

I'd love to have ventilation with heat exchanger, but that's basically unheard of where I live.

Re: First clean water, now clean air

#117

Post by balfirevic »

symlinkk wrote: post #112
Abekkus wrote: post #35

Earlier quoted context omitted.

Or you could save $2k on materials & labor, and put in a filtered vent fan. You only need around 15CFM per resident. Household HRVs & ERVs have suspiciously low heat efficiencies for their costs.

Are you talking about a fan that simply blows outside air in? Wouldn’t that basically fight what the HVAC is doing? AFAIK the only real solution is an ERV / HRV, and they are extremely expensive (like $10k in my area)

No direct experience, but single-room HRV units look pretty cheap

https://www.amazon.co.uk/single-room-heat-recovery-ventilati...

Re: First clean water, now clean air

#118

Post by bruckie »

sizzle wrote: post #108
schiffern wrote: post #70

Earlier quoted context omitted.

Note that, to minimize pollution from vehicle exhaust, you want to set your air to "recirculate" . Unsurprisingly, the roadway is where vehicle pollution is most concentrated! https://www.latimes.com/science/sciencenow/la-xpm-2013-sep-1... Usually what I do is set it on recirculate, and then every ~10 minutes I periodically "flush" the CO2-laden interior air for a minute or so. Ideally, I'm able to do this "flush" wh…

I always crack my sunroof an inch and pull the shade forward go get some fresh air in recirculate mode so I’m not picking up crap from the engine bay. How does the fresh air mode on the car not pull in CO gases from the engine bay? Surely a pleated cabin filter is not enough to stop it? Or does the air come from the manifold air intake?

There should be very low levels of CO (at least from your car) in the engine bay, since exhaust is vented out the back of the car, and your engine shouldn't be leaking exhaust gases in other places. You might have some CO there from the cars in front of you, though.

Re: First clean water, now clean air

#119

Post by aidenn0 »

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,…

I do wonder how much of it is CO2 levels themselves and how much of it is high CO2 being a proxy for poor ventilation.

Re: First clean water, now clean air

#120

Post by aidenn0 »

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?

Aside from urban noise, I don't sleep well if an open window is too close to my bed because I end up with congested sinuses.
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