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First clean water, now clean air

finmoorhouse.com

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Re: First clean water, now clean air

#31

Post by brianmcc »

makomk wrote: post #27
ZeroGravitas wrote: post #16

It doesn't take away from the general thrust of the post but it's interesting that lack of quality sewage treatment leading to it being dumped into rivers is thought to be a key issue in the current British council voting: Local elections 2023: How sewage topped the political agenda https://www.bbc.co.uk/news/uk-politics-65190097

The Victorian-era sewage systems described in this article are actually one of the key reasons that sewage is ending up in rivers and the sea in the first place. Notice how they worked: sewage was collected, pumped, and dumped downstream of London. It was not treated. Most of the UK's sewage treatment is retrofitted to sewage systems that were never designed to have it. This causes various problems, the main one bein…

It also seems another Brexit issue - treatment chemicals being that bit harder to bring in:

https://www.thelondoneconomic.com/news/brexit-to-blame-for-u...

Re: First clean water, now clean air

#32

Post by mensetmanusman »

adolph wrote: post #7
throw0101b wrote: post #5

> Ultraviolet germicidal irradiation (UVGI) Please do not do/use this. Generally anything that is 'active', like UV lamps or ozone emitters, is not a good idea: * https://www.youtube.com/watch?v=hSFQQpgvgeo&t=6m1s * Interviewee: https://civmin.utoronto.ca/home/about-us/directory/professor... All that's needed for good indoor air quality (IAQ) is an ERV/HRV which exhausts stale indoor air and brings in fresh outdoor a…

That is an interesting explanation. I won’t summarize other than to say that as someone who might have added UV next hardware cycle, there were several A-Ha moments. Well worth watching.

UV is more than UV, there is UVA UVB UVC, etc.

Some UVC generates Ozone, some do not. Wavelength and spectral Q factor matter.

It’s possible to have a UV system that does what you want without the downside, but it does cost.

Re: First clean water, now clean air

#33

Post by morkalork »

XorNot wrote: post #29
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…

Before I stopped being in offices I was looking for a portable CO2 monitor to take into meetings to see how quickly we ended up at 1000+ppm. The tendency to overcrowd meeting rooms I was convinced was basically a driver in devaluing them - the CO2 is going up and up and up and people's cognition is slowly ebbing alongside regular old fatigue.

I always blamed it on heat accumulation, after stuffing all those bodies, laptops and even old inefficient lighting/projectors into a confined space it gets way too warm, then the body slows down to compensate.

Re: First clean water, now clean air

#34

Post by za3faran »

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,…

Which monitor manufacturer are you using?

Re: First clean water, now clean air

#35

Post by Abekkus »

sbaiddn wrote: post #15
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,…

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.

Re: First clean water, now clean air

#36

Post by gizmo686 »

leblancfg wrote: post #25

I wish the author had spent more time to unfold the public vs private debate here: >if a country installed all the measures I mentioned As opposed to the wastewater infrastructure in the first section that can be mandated and put in motion by a government, it's up to individuals and institutions to install the measures. This makes implementation significantly more challenging, as it relies on the collective efforts a…

Governments are perfectly capable of setting building codes. This isn't an instance fix, but would be effective over the long term.

Governments also have a well established mechanism to incentives faster compliance: tax refunds to offset the cost of improvement. We already offer such incentives for energy efficiency improvements (some of which actively harm ventilation).

From an engineering perspective, the clean air proposals are much easier than wastewater management. There is no centralized infastructure needed. Every building can be upgraded independently, and the people in that building will see an immediate benefit.

Further, the upgrades needed are typically not that major. Most building already have a forced air HVAC solution. These solutions already have inline air filters, and often already have the ability to actively pull in fresh air.

We can get significant improvement my simply leaving the fan on these units running regardless of if they are actively heating/cooling; and using already available high quality filters.

In that subject, a quick PSA to home owners: if you have not changed your HVACs filter recently, you probably should.

Re: First clean water, now clean air

#37

Post by Cthulhu_ »

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,…

It's a tradeoff, because good ventilation - ideally just open a window - also means heat is leaking out of the house, which costs money (and co2 emissions) to restore.

There's cyclic systems, but I live in a neighbourhood where some houses were equipped with it; on the proper setting, it was too loud so people turned it down, then people got sick from high CO2 levels in their house.

Re: First clean water, now clean air

#38

Post by anonyfox »

LeonM wrote: post #9
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 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?

Re: First clean water, now clean air

#39

Post by Cthulhu_ »

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.

It'll depend on the tent, I don't immediately associate tents with good ventilation.

Re: First clean water, now clean air

#40

Post by Cthulhu_ »

GuB-42 wrote: post #26
c3534l wrote: post #8

Earlier quoted context omitted.

> , it shocked me and raised awareness to how poor my indoor ventilation is. Do you want indoor circulation? Wouldn't that just mean your apartment loses heat/AC?

Yes, ventilation causes heat losses, but it is necessary. There are ways around it though. The simplest is to not make sure ventilation goes where it needs to go. Modern buildings use mechanical ventilation to make sure every living space gets properly ventilated so one room doesn't get too much and another too little. Even better, some building use heat exchangers to heat/cool the incoming air with outgoing air, min…

The issue with heat exchangers and the like is noise on the one hand (can be suppressed of course), having it on the right setting (not too high if there's few people, not too low if there's many), and keeping the conduits clean (dust, moisture and heat is a great combo for some).
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