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A paradigm shift to combat indoor respiratory infection

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Re: A paradigm shift to combat indoor respiratory infection

#41

Post by daniellarusso »

prof-dr-ir wrote: post #7

From the article: "It is not known exactly what fraction of infections could be prevented if all building and transport ventilation systems on the planet were ideal (in terms of controlling airborne infections), or the cost of design and retrofitting to make them ideal." I think this is the key question. Surely better ventilation would have prevented some infections in the covid pandemic. But how many? And to decide…

This is the Ben Franklin / John Adams debate when they shared a small room together overnight with one window.

“When Adams explained that he didn’t want to catch an illness from the cold night air, Franklin countered that the air in their room was even worse.”

https://www.mentalfloss.com/article/54169/time-ben-franklin-...

Re: A paradigm shift to combat indoor respiratory infection

#42

Post by ddxxdd »

rightbyte wrote: post #39
ddxxdd wrote: post #32

Earlier quoted context omitted.

>Of course, that flies in the face of all efforts to make things green…which involve better insulation, sealing windows against leaks, more air filtration systems and etc. If anyone has a half-hour of time to waste, you can look into the science of "countercurrent heat exchangers". It's fascinating to see how 2 pipes of air current switch temperatures when they're in contact and moving in opposite directions. So if y…

> It's fascinating to see how 2 pipes of air current switch temperatures when they're in contact and moving in opposite directions. Shouldn't the air ideally move in the same direction?

Nope, because they will both end up at the same temperature, namely, the average temperature halfway between the two previous temperatures.

In a countercurrent heat exchanger, the hot air will get colder and colder until it is at the same temperature as the cold air, and the cold air will get hotter and hotter until it is the same temperature as the hot air.

This is because the hot air is not warming up the same air molecules that it relies on to cool down, and the cold air is not cooling down the same air molecules that it relies on to warm up. Each current of air gives up a part of their heat/coldness, becomes colder/hotter, and then moves towards a section of pipe that's even colder/hotter than the previous section of pipe.

A picture is worth a thousand words, although it takes some staring and studying before the concept finally clicks: https://en.wikipedia.org/wiki/Countercurrent_exchange#/media...

Re: A paradigm shift to combat indoor respiratory infection

#43

Post by f6v »

ur-whale wrote: post #25
prof-dr-ir wrote: post #7

From the article: "It is not known exactly what fraction of infections could be prevented if all building and transport ventilation systems on the planet were ideal (in terms of controlling airborne infections), or the cost of design and retrofitting to make them ideal." I think this is the key question. Surely better ventilation would have prevented some infections in the covid pandemic. But how many? And to decide…

There is a "law of unintended effects" question as well: if we were to live - and presumably grow up - in such a sanitized environment, what would happen to our immune system. There's a sizeable chance it would be extremely weak and that'd we'd be incapable of resisting many disease on our own and therefore would become completely dependent on the air cleaning infrastructure.

You still eat fresh fruits and vegetables, touch the surfaces on your way to work etc. There’re countless pathogens everywhere. So I guess we would be fine?

You’re right that our immune system didn’t evolve to be in a sterile environment. But we also weren’t meant to be that close to that many humans.

Re: A paradigm shift to combat indoor respiratory infection

#44

Post by f6v »

colechristensen wrote: post #8

It seems overly complicated. Just raise the air exchange per person and or per volume by a significant factor and mandate a very fine particulate filter. You could do many measurements and lots of theory but nobody is going to engineer their buildings like cleanrooms anyway so the results of a lot of science wouldn’t be so good regardless.

Now, who’s gonna pay for that?

Re: A paradigm shift to combat indoor respiratory infection

#45

Post by [deleted] »

rightbyte wrote: post #39
ddxxdd wrote: post #32

Earlier quoted context omitted.

>Of course, that flies in the face of all efforts to make things green…which involve better insulation, sealing windows against leaks, more air filtration systems and etc. If anyone has a half-hour of time to waste, you can look into the science of "countercurrent heat exchangers". It's fascinating to see how 2 pipes of air current switch temperatures when they're in contact and moving in opposite directions. So if y…

> It's fascinating to see how 2 pipes of air current switch temperatures when they're in contact and moving in opposite directions. Shouldn't the air ideally move in the same direction?

[deleted]

Re: A paradigm shift to combat indoor respiratory infection

#46

Post by bsenftner »

vishnugupta wrote: post #38
newsbinator wrote: post #19

Earlier quoted context omitted.

> EARLY ONE MORNING, Linsey Marr tiptoed to her dining room table, slipped on a headset, and fired up Zoom. On her computer screen, dozens of familiar faces began to appear. She also saw a few people she didn’t know It’s really hard for me to read a WIRED article for information. I mean I realize that’s not what it’s there for but it takes forever to get into the content of the article.

> When the call ended, Marr sat back heavily, feeling an old frustration coiling tighter in her body. She itched to go for a run, to pound it out footfall by footfall into the pavement

This style of writing is so present tense sensationalized, I cease to believe what is written simply because all this fictionalized present tense prose they dress the article up is 100% made up - so how is one to take the "facts" seriously?

Re: A paradigm shift to combat indoor respiratory infection

#47

Post by K0balt »

andi999 wrote: post #26
bellyfullofbac wrote: post #23

Earlier quoted context omitted.

Hear hear. Maybe Wired should talk about the coffee she's sipping, made from beans harvested on the south coast of Java, where there is a legend of a queen who drowned...

I need more detail... what happened to the queens relatives.

Forget the relatives, where did those BUTONS on her shoes come from!

Re: A paradigm shift to combat indoor respiratory infection

#48

Post by ur-whale »

f6v wrote: post #43
ur-whale wrote: post #25

Earlier quoted context omitted.

There is a "law of unintended effects" question as well: if we were to live - and presumably grow up - in such a sanitized environment, what would happen to our immune system. There's a sizeable chance it would be extremely weak and that'd we'd be incapable of resisting many disease on our own and therefore would become completely dependent on the air cleaning infrastructure.

You still eat fresh fruits and vegetables, touch the surfaces on your way to work etc. There’re countless pathogens everywhere. So I guess we would be fine? You’re right that our immune system didn’t evolve to be in a sterile environment. But we also weren’t meant to be that close to that many humans.

>So I guess we would be fine?

Can you catch airborne respiratory diseases from eating fruit?

What I'm saying is: we run the risk of never being able to go outside again if we eliminate all airborne pathogens.

Re: A paradigm shift to combat indoor respiratory infection

#49

Post by mrow84 »

rightbyte wrote: post #39
ddxxdd wrote: post #32

Earlier quoted context omitted.

>Of course, that flies in the face of all efforts to make things green…which involve better insulation, sealing windows against leaks, more air filtration systems and etc. If anyone has a half-hour of time to waste, you can look into the science of "countercurrent heat exchangers". It's fascinating to see how 2 pipes of air current switch temperatures when they're in contact and moving in opposite directions. So if y…

> It's fascinating to see how 2 pipes of air current switch temperatures when they're in contact and moving in opposite directions. Shouldn't the air ideally move in the same direction?

There is a diagram illustrating why not in the wikipedia article: https://en.wikipedia.org/wiki/Countercurrent_exchange

Re: A paradigm shift to combat indoor respiratory infection

#50

Post by stevenhuang »

colechristensen wrote: post #8

It seems overly complicated. Just raise the air exchange per person and or per volume by a significant factor and mandate a very fine particulate filter. You could do many measurements and lots of theory but nobody is going to engineer their buildings like cleanrooms anyway so the results of a lot of science wouldn’t be so good regardless.

Doing that without the ability to quantify the affect is also a nonstarter. How would you know it's even making an appreciable difference, or if a lower factor would perform just as well?

Without the groundwork theory to rely on, you'd be hard pressed to convince new buildings to do something like that on a whim.

> You could do many measurements and lots of theory but nobody is going to engineer their buildings like cleanrooms anyway so the results of a lot of science wouldn’t be so good regardless.

This is a very strange and confused sentiment.

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