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Improving ventilation will help curb SARS-CoV-2

economist.com

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Re: Improving ventilation will help curb SARS-CoV-2

#61

Post by mherdeg »

My town's school system is all in on healthy buildings -- they got parent MD/PhDs to read the literature and invite outside experts to advise, then they set minimum air change per hour and minimum filtration criteria (something like, classrooms may reopen iff they have 5 air changes per hour with outdoor or MERV 13+ filtered air). They did a bunch of HVAC work to support this goal and have reopened okay.

The town's other public buildings as far as I can have ignored this and I think the libraries are just gonna reopen and hope for the best.

Advocates of healthy buildings have been telling us about the risks of low airflow (focusing mostly on cognitive effects of high CO2 vs the disease impacts). It sucks but the pandemic is their once in a generation opportunity to push change in indoor air quality -- I hope some of it sticks.

Re: Improving ventilation will help curb SARS-CoV-2

#62

Post by benatkin »

christophilus wrote: post #38
harikb wrote: post #30

Earlier quoted context omitted.

that was specifically about calling Covid a hoax. Those who were fighting against this censorship weren’t fighting for Covid being airborne or not

My recollection was that they banned disagreeing with the WHO[0]. The examples given in that article are fair enough for banning, but they banned scientists who were not quite so crazy[1]. Anyway, that’s based on my memory (which is often faulty), but those links seem to corroborate it. [0] https://www.bbc.com/news/technology-52388586 [1] https://support.google.com/youtube/thread/46573762/why-is-yo...

There is a lot of straw-manning going on, so if you say you disagree with the WHO on a minor point, you could be accused of calling COVID-19 a hoax.

Re: Improving ventilation will help curb SARS-CoV-2

#63

Post by Izkata »

timr wrote: post #53
kevin_nisbet wrote: post #27

Earlier quoted context omitted.

I certainly don't think you should be ridiculed for the notion, although I think my counter thought would be why should it be one or the other, and how confident are we in the engineering side of the solution at a wide scale. To my knowledge masks are a low cost / lost risk way to reduce the spread, and countries that had faster uptake and higher rates of compliance in mask usage did see lower overall case counts. Th…

> To my knowledge masks are a low cost / lost risk way to reduce the spread, and countries that had faster uptake and higher rates of compliance in mask usage did see lower overall case counts. 1) This isn't really true. There's not a lot of correlation between what nations/states did, and where they ended up. You can find observational papers on both sides of every question (for example, specific to masks, recently:…

> (and before anyone says it: yes, it's entirely possible to have conducted clinical trials of masks. a cluster randomized trial, for example, could have been used to establish efficacy early in the pandemic. That we didn't even consider doing these "because it's a pandemic" is one of the biggest scientific lost opportunities of our lifetime.)

There were studies done; all the way back in March 2020 there was an infographic making the rounds showing a rough estimate of percentage of particles filtered/let through by different types of cloth masks and N95/etc. If I remember right, all the cloth masks let through >50% of particles.

Re: Improving ventilation will help curb SARS-CoV-2

#64

Post by tharkun__ »

christophilus wrote: post #38
harikb wrote: post #30

Earlier quoted context omitted.

that was specifically about calling Covid a hoax. Those who were fighting against this censorship weren’t fighting for Covid being airborne or not

My recollection was that they banned disagreeing with the WHO[0]. The examples given in that article are fair enough for banning, but they banned scientists who were not quite so crazy[1]. Anyway, that’s based on my memory (which is often faulty), but those links seem to corroborate it. [0] https://www.bbc.com/news/technology-52388586 [1] https://support.google.com/youtube/thread/46573762/why-is-yo...

They are not the only ones at all. Same thing happened to a lot of other people. There was for example a lot of good information from the Italian National Institute of Health that simply listed the number and type of comorbidities in deceased Covid patients. Mentioning these numbers, even with proper citation was cause for being banned/not being approved by moderators. It didn't fit the official narrative.

Like my sibling poster said, it probably triggered the "covid hoax" spidey senses. People are not rational in these times. They're emotional and won't even listen enough or think enough to understand the difference between looking at facts and discussing them vs. calling it a hoax. Covid is very real. I know from multiple close friends affected. I was also told via official channels that anyone obese would dare badly and die. Anecdotal data: Yet some very obese friends made it through without more than a few mild symptoms. Months later new research came out that said being sedentary is much worse than being obese. This friend while being obese is very active. No car, walks everywhere, physical labour job etc. Just telling this story would probably get me banned on certain sites.

Re: Improving ventilation will help curb SARS-CoV-2

#65

Post by carols10cents »

toomim wrote: post #46
actually_a_dog wrote: post #24

Earlier quoted context omitted.

It's still ridiculous because it's incredibly expensive compared to just wearing masks.

No it's not. Open a window and stick a fan in it. Total cost: $20. Consider that during the pandemic, the good N95 masks were not even available for any price, so people were wearing flimsy cotton things that only block 20% of particulates. Opening a window with a fan works far better if you do it right and uses materials we still had in supply.

Opening a window, even with the fan blowing out, is not exactly an option in the winter. Nevermind all the rooms without windows...

Re: Improving ventilation will help curb SARS-CoV-2

#66

Post by kevin_nisbet »

timr wrote: post #53
kevin_nisbet wrote: post #27

Earlier quoted context omitted.

I certainly don't think you should be ridiculed for the notion, although I think my counter thought would be why should it be one or the other, and how confident are we in the engineering side of the solution at a wide scale. To my knowledge masks are a low cost / lost risk way to reduce the spread, and countries that had faster uptake and higher rates of compliance in mask usage did see lower overall case counts. Th…

> To my knowledge masks are a low cost / lost risk way to reduce the spread, and countries that had faster uptake and higher rates of compliance in mask usage did see lower overall case counts. 1) This isn't really true. There's not a lot of correlation between what nations/states did, and where they ended up. You can find observational papers on both sides of every question (for example, specific to masks, recently:…

I'm not sure if I should interpret this as masks are an ineffective tool, or more narrowly that combined with other efforts it's unclear what the impact was since there's a large degree of opinion on the matter compared to data with a higher standard of a peer reviewed double blind study.

With masks being such a hot topic in certain regions, it would seem unreasonable to conclude that there is only correlation available.

The opinion I'm referring to and cited is in line with this one (just did a quick google search, I don't remember the original source of my assertion): https://www.sciencedaily.com/releases/2020/06/200624082657.h...

There appear to be a number of smaller studies available as well: https://en.wikipedia.org/wiki/Face_masks_during_the_COVID-19... which if cloth masks are effective it would seem to me to be reasonable to extend this to rate of adoption and a contributing factor.

Re: Improving ventilation will help curb SARS-CoV-2

#67

Post by redis_mlc »

nradov wrote: post #50
pyk wrote: post #10

Earlier quoted context omitted.

If you have forced air, you can get a UV bulb that all air passes by for $200-300 - just requires drilling some holes and an AC plug. Also helps with killing mold and bacteria as an added benefit (and some of the original intention for the devices, e.g., OdorStop).

Are there any independent test results to show how effective those UV bulbs are at killing pathogens?

> Are there any independent test results to show how effective those UV bulbs are at killing pathogens?

Why, did you thoroughly research it before sealioning? No, you didn't.

Here's the first google result:

https://www.fda.gov/medical-devices/coronavirus-covid-19-and...

UV is a well-known disinfectant.

When camping, you can put naturally-found water in a clear plastic bag for a couple of hours in the sun.

In some parts of Asia, they installed UV lights in their transit garages and irradiated buses overnight during corona.

Re: Improving ventilation will help curb SARS-CoV-2

#68

Post by timr »

kevin_nisbet wrote: post #66
timr wrote: post #53

Earlier quoted context omitted.

> To my knowledge masks are a low cost / lost risk way to reduce the spread, and countries that had faster uptake and higher rates of compliance in mask usage did see lower overall case counts. 1) This isn't really true. There's not a lot of correlation between what nations/states did, and where they ended up. You can find observational papers on both sides of every question (for example, specific to masks, recently:…

I'm not sure if I should interpret this as masks are an ineffective tool, or more narrowly that combined with other efforts it's unclear what the impact was since there's a large degree of opinion on the matter compared to data with a higher standard of a peer reviewed double blind study. With masks being such a hot topic in certain regions, it would seem unreasonable to conclude that there is only correlation availa…

Note that I've edited my comment to better reflect my thoughts (probably since you wrote this).

I don't think you should take this one paper as some kind of definitive rebuttal on masks. You should interpret it as a reasonable summary of current evidence, as well as a not-terrible analysis of US states that poses some serious challenges to the effectiveness of mask mandates.

That said, an editorial/letter in science daily is not a rebuttal, and wikipedia is useless for politically sensitive questions. There are many papers on both sides of the issue, and it's easy to cherry-pick a set that support any particular position.

Is it the end of the discussion? No. But It's not as cut-and-dried as people make it seem. The evidence base for masks is very low-quality. The issue became political, and as with all things political today, nuance and reason were tossed out the window.

Re: Improving ventilation will help curb SARS-CoV-2

#69

Post by timr »

Izkata wrote: post #63
timr wrote: post #53

Earlier quoted context omitted.

> To my knowledge masks are a low cost / lost risk way to reduce the spread, and countries that had faster uptake and higher rates of compliance in mask usage did see lower overall case counts. 1) This isn't really true. There's not a lot of correlation between what nations/states did, and where they ended up. You can find observational papers on both sides of every question (for example, specific to masks, recently:…

> (and before anyone says it: yes, it's entirely possible to have conducted clinical trials of masks. a cluster randomized trial, for example, could have been used to establish efficacy early in the pandemic. That we didn't even consider doing these "because it's a pandemic" is one of the biggest scientific lost opportunities of our lifetime.) There were studies done; all the way back in March 2020 there was an infog…

There have been a number of laboratory studies performed that show varying levels of effectiveness for different kinds of masks and materials (where "effectiveness" is defined in all sorts of different ways that may or may not be relevant). Prior to Covid-19, there was a low-quality evidence base that didn't provide much signal either way:

https://www.cebm.net/covid-19/masking-lack-of-evidence-with-...

Strapping a mask on a mannequin or to a nozzle is, of course, very different than asking people to wear them everywhere. For evidence of real-world effectiveness of a medical intervention, you do a controlled trial. We could have done some, but we did not. It is notable -- but not at all perfect -- that the only RCT conducted with masks and Covid-19 in 2020 found no significant personal protective effect:

https://www.acpjournals.org/doi/10.7326/M20-6817

It is a well-done study, and certainly limits the claims that can be made for masks, but doesn't answer every question. A good cluster RCT might have been able to address the question of whether or not masks protect others, for example.

Re: Improving ventilation will help curb SARS-CoV-2

#70

Post by toast0 »

behnamoh wrote: post #29
SllX wrote: post #6

> The who therefore played down the risks of aerosols, issuing guidance via its Twitter and Facebook pages at the end of March 2020 that the general public need not worry. “FACT: #COVID19 is NOT airborne,” it said, adding that any claims to the contrary were “misinformation”. Not quite the money quote, but on reading this I wanted to point out one little thing. This is also a form of authoritarianism, not the splashy…

> Fortunately, we also live in a world where the UN and its agencies do not have a monopoly on good information. We live in a world where the UN is basically a formality. I don't see how this organization has been helpful in solving world problems and preventing wars at all.

The ITU (a UN agency) helps solve the world problem of what country code to use to call countries, and coordinates new codes for new countries. If that's not a world problem, and it's not solved by the UN, I don't know what would satisfy you.

There have been very few wars since the UN was formed. Instead, we mostly have armed conflicts and military engagements, preventing many wars.

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