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First clean water, now clean air

finmoorhouse.com

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Re: First clean water, now clean air

#51

Post by Empact »

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…

> All that's needed for good indoor air quality (IAQ) is an ERV/HRV which exhausts stale indoor air and brings in fresh outdoor air (through a filter)

The recommendations you mention are together features of the Passive House[1] building standard that seeks low energy use as well. If you build a building to a high standard, it will have a tighter envelope to retain heat/cool and protect against water intrusion. If the envelope is tight, you must actively manage airflow through an ERV/HRV. The consequence is that these buildings are supplied with continuous fresh air, and their ERV can be set up to dynamically react to air quality and other issue to ramp up the transfer.[2]

There's a subculture of builders pursuing these qualities in their building, represented for example by groups like "Building Science and Beer" in Austin[3], and Matt Risinger's Build Show[4].

[1] https://www.treehugger.com/what-is-a-passive-house-principle...

[2] https://www.broan-nutone.com/en-us/ai-series

[3] https://www.instagram.com/bs_and_beer_atx/

[4] https://www.youtube.com/@buildshow/videos

Re: First clean water, now clean air

#52

Post by switchbak »

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?

Some new buildings use an HRV system which circulates fresh air in while recovering some of the heat of the exhaust air.

Re: First clean water, now clean air

#53

Post by switchbak »

endisneigh wrote: post #18
kevincox wrote: post #13

Earlier quoted context omitted.

You can use a heat exchanger to get "fresher" air while keeping the heat/cool inside. Although many places don't have this in place. It is probably mostly due to lack of awareness or concern than any technical reason.

Cost

Letting your warm air go directly outside also has a cost.

Getting poor air quality for decades also has a cost.

Typing more than a one word reply is pretty cheap though.

Re: First clean water, now clean air

#54

Post by endisneigh »

switchbak wrote: post #53
endisneigh wrote: post #18

Earlier quoted context omitted.

Cost

Letting your warm air go directly outside also has a cost. Getting poor air quality for decades also has a cost. Typing more than a one word reply is pretty cheap though.

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

Re: First clean water, now clean air

#55

Post by markrankin »

“The expectation of clean water in wealthy countries is enabled by technology and infrastructure; like effective sewage systems and water treatment facilities. But to a large extent it is also enabled, and was initially bootstrapped, by sound policymaking and regulation.

Regulation requires verification.”

Regulation of water does not require verification. We live on a planet where clean water is abundant and cannot escape the planet’s atmosphere. Why you think we need to measure how this is verified is beyond the beyond’s.

Here’s a wiki page reference if you need help measuring how much water exists on Earth:

While the majority of Earth's surface is covered by oceans, those oceans make up just a small fraction of the mass of the planet. The mass of Earth's oceans is estimated to be 1.37 × 1021 kg, which is 0.023% of the total mass of Earth, 6.0 × 1024 kg. An additional 5.0 × 1020 kg of water is estimated to exist in ice, lakes, rivers, groundwater, and atmospheric water vapor.[20]

https://en.m.wikipedia.org/wiki/Origin_of_water_on_Earth#Ear...

Re: First clean water, now clean air

#56

Post by bsenftner »

hammock wrote: post #46
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,…

When driving, does running the air (not on recirc) not exchange enough air?

Opening a car window or running air not on recirc immediately drops the readings to safe levels. I also noticed when in the Uber returning from the airport, the air was in the high 3000's and I explained to the driver, he opened all the windows and I think I scared him a bit.

Re: First clean water, now clean air

#57

Post by twojacobtwo »

markrankin wrote: post #55

“The expectation of clean water in wealthy countries is enabled by technology and infrastructure; like effective sewage systems and water treatment facilities. But to a large extent it is also enabled, and was initially bootstrapped, by sound policymaking and regulation. Regulation requires verification.” Regulation of water does not require verification. We live on a planet where clean water is abundant and cannot e…

There are only so many ways and places to extract clean water for large populations in an efficient way. Once water is used, it has to go somewhere, which is back into the water system. Every person/population downstream then no longer has 'clean water' without verification. We could have 10x the clean water we have now and we would still have to consider this aspect.

Re: First clean water, now clean air

#58

Post by throw0101a »

anecdotal1 wrote: post #43
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…

Reme Halo is what you want. That's what I put in when I installed my ERV. Reme uses UV against titanium dioxide which releases airborne peroxides which takes out bacteria/viruses/yeast/mold This is the same tech used in self-cleaning concrete -- just add titanium dioxide and let the sun do the work

> Reme Halo is what you want. That's what I put in when I installed my ERV.

Please view the video. The interviewee:

> Jeffrey Siegel, Ph.D., is Professor of Civil Engineering at the University of Toronto and a member of the university’s Building Engineering Research Group. He holds joint appointments at the Dalla Lana School of Public Health and the Department of Physical & Environmental Sciences. He holds an M.S. and Ph.D. in Mechanical Engineering from the University of California, Berkeley as well as a B.Sc. from Swarthmore College. He is fellow of ASHRAE and a member of the Academy of Fellows of ISIAQ. His research interests including healthy and sustainable buildings, ventilation and indoor air quality in residential and commercial buildings, control of indoor particulate matter, the indoor microbiome, and moisture interactions with indoor chemistry and biology. Dr. Siegel is an active member of ISIAQ and ASHRAE and was an associate editor for the journal Building and Environment from 2014-2018. He teaches courses in indoor air quality, sustainable buildings, and sustainable energy systems. Prior to his position at the University of Toronto, Dr. Siegel was an Associate Professor at the University of Texas.

* https://civmin.utoronto.ca/home/about-us/directory/professor...

Peroxide has at best generally been found to useless, and at worst you're introducing active chemistry to your ventilation system (including ozone). If you want to get rid of garbage in your air then (a) exchange it at ASHRAE-recommended volumes, and (b) use high-MERV/HEPA filters.

In wildfire zones and in wildfire season you can perhaps add charcoal filters—if your system is designed to handle the pressure/head loss—to get rid of the smoke-y smells.

There is no need to conduct chemistry experiments on yourself.

Re: First clean water, now clean air

#59

Post by throw0101a »

mensetmanusman wrote: post #32
adolph wrote: post #7

Earlier quoted context omitted.

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.

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

The main downside is that you are introducing a chemistry experiment into your ventilation system.

If you want clean air, then (a) cycle in/outside air at ASHRAE-recommended volumes, and (b) use high-MERV/HEPA filters.

In wildfire zones and in wildfire season you can perhaps add charcoal filters—if your system is designed to handle the pressure/head loss—to get rid of the smoke-y smells.

Re: First clean water, now clean air

#60

Post by throw0101a »

Empact wrote: post #51
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…

> All that's needed for good indoor air quality (IAQ) is an ERV/HRV which exhausts stale indoor air and brings in fresh outdoor air (through a filter) The recommendations you mention are together features of the Passive House[1] building standard that seeks low energy use as well. If you build a building to a high standard, it will have a tighter envelope to retain heat/cool and protect against water intrusion. If th…

> The recommendations you mention are together features of the Passive House[1]

ERV/HRV are actually part of regular building codes in many areas. The province of Ontario:

* https://www.greenbuildingadvisor.com/article/ontario-imposes...

* https://airfixture.com/blog/ontario-building-code-ventilatio...

* http://www.mah.gov.on.ca/AssetFactory.aspx?did=15947

* https://web.archive.org/web/20180626073728/http://www.mah.go...

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