[HN Gopher] Why don't we just open the windows? Covid-19 prevent...
___________________________________________________________________
Why don't we just open the windows? Covid-19 prevention lost in
translation
Author : stmw
Score : 48 points
Date : 2021-11-28 21:00 UTC (2 hours ago)
(HTM) web link (www.bmj.com)
(TXT) w3m dump (www.bmj.com)
| 323 wrote:
| Ventilation is energetically expensive, and can be even
| impossible to retrofit (windows that don't open, ...)
|
| Purification however is energetically very cheap (just a fan
| blowing through a filter, maybe with a UV led, no temperature
| change). And has the bonus benefit of removing other dangerous
| particulate stuff from the air (dust, smoke, ...)
| koheripbal wrote:
| Most office buildings also do not have windows that open at
| all.
| newaccount74 wrote:
| Heat exchangers can recover a large fraction of the energy lost
| through ventilation. Modern systems can even recover humidity
| from the air leaving the building.
|
| Air purifiers are very loud and mostly effective at removing
| particulates. If you want to remove VOCs, formaldehyde and CO2
| then ventilation is a lot more effective.
|
| A well designed ventilation system can be completely inaudible.
| legulere wrote:
| Automated ventilation saves energy. You don't need to open
| windows anymore which leads to less heat or cold coming in. If
| your ventilation system has a heat exchanger it's performing
| even better. It's impossible to build highly efficient houses
| without automated ventilation.
| sharperguy wrote:
| A metaphor I was thinking of earlier.
|
| If a guy is going to piss on you, you're going to be happy if he
| has to keep a pair of speedos on as he attempts it. You could
| also just move further away from him.
|
| But if you're both swimming in the same pool while he pisses in
| it, those speedos will make little difference anymore. Neither
| will your distance from him help very much.
|
| What will help much more is the amount of water in the pool, and
| the amount of fresh water being pumped in and old water pumped
| out.
| orblivion wrote:
| It baffles me that Fauci etc didn't mention this in the next
| breath after hand washing and masking. It's easy during nice
| weather.
| IG_Semmelweiss wrote:
| To this day, there is no mandate whatsoever in any public
| transport to keep windows open. NiH? CDC? Missing in action
| thanks a lot.
|
| Uber could simply ask customers to always ask for windows down.
|
| This to me is the biggest unsung crime of the pandemic by govt
| officials and private industry alike.
| fennecfoxen wrote:
| Uber and Lyft in fact require customers to agree to keep
| windows open "when possible" in the same pop up as reminding
| them to wear masks. Short of intrusive integrations with some
| hypothetical car window status sensors, not presently deployed
| in the fleet, that's getting close to the limits of what can be
| effectively achieved for now.
| bb123 wrote:
| Good ventilation is easy to do in the summer months, but it is
| winter in the northern hemisphere at the moment, and fuel prices
| are at all time highs. That means adequate ventilation is likely
| an expensive thing to achieve. Not to mention the environmental
| consequences of extra energy consumption, along with the plastic
| pollution from littered masks and lateral flow tests - they're
| absolutely everywhere.
| IG_Semmelweiss wrote:
| I'm sorry but this is unacceptable.
|
| We have shut down entire industries, made some people 2nd class
| citizens, and wrote blank checks to healthcare companies to
| solve this problem,
|
| and your concern is lost heat and the environment ?
|
| Any common sense government would have mandated open windows a
| long time ago, in most transportation systems and in federal
| buildings that could bear it, instead we wasted valuable time
| with politics
| oleganza wrote:
| No, you shut down entire industries not because of poor vents
| in a concert, but because some overly powerful, yet
| replaceable and hysterical bureaucrats decided to cover their
| asses (from being eaten by the exact same bureaucrats) with
| arbitrary loud and visible policies that had little
| correlation with actually solving any problems.
|
| Notice similarity between places like Florida (less power-
| hungry governments + freedom-loving population) and places
| like Belarus and Russia (more authoritarian central gov that
| does not fear for losing its seat in the next election): both
| were shutting down things to a much lesser degree than
| everyone else. I think the reason is exactly the combo of "I
| can have arbitrary power as long as I have good PR" in the
| average democratic political environment.
| inamberclad wrote:
| What's the end-game there? Opening windows doesn't eradicate
| the virus. Admittedly, we don't have a clear end-game as
| things stand, but what you suggest is just another mitigation
| factor, not a solution.
| bb123 wrote:
| I'm not sure what there is to accept? I never said it wasn't
| worth it, just that there are financial and environmental
| costs to consider. Where I live heating a building is
| expensive and many people can not afford to do it adequately
| at the best of times.
| GhettoComputers wrote:
| They already solved this in NYC and Chicago with extra hot
| radiators by windows.
|
| https://www.bloomberg.com/news/articles/2020-08-05/the-curio...
|
| The "spent breath" of the occupants of poorly ventilated homes
| contributed to 40% of the deaths in the country, he claimed, and
| often said "man's own breath is his greatest enemy." He would
| spend decades promoting the cause, designing ventilation schemes
| for buildings, penning a 1869 book, Leeds on Ventilation, and
| lecturing across the country. He explained his ideas with the aid
| of a "magic lantern" projector -- think old-timey Powerpoint
| presentations. He'd show slides of a family in their drawing
| room, then add a slide showing red air coming out of the father's
| mouth. The child crawling on the floor would eventually fall
| over. It "scared people to death," Holohan says.
|
| https://www.npr.org/2020/12/10/945136599/how-spanish-flu-pan...
| timschmidt wrote:
| Reminds me of The Lost Art of Steam Heating by Dan Holohan:
| https://www.youtube.com/watch?v=TQB0KK2rxcw
| chillwaves wrote:
| There is also a problem of comfortable humidity levels. If you
| just have open windows, it seems like you will have very dry
| air.
|
| There are modern solutions for air exchanges that do retain
| some of the heat and moisture while allowing for fresh air to
| ventilate the indoor space.
|
| https://www.explainthatstuff.com/heat-recovery-ventilation.h...
| Madmallard wrote:
| ?
|
| If your windows are open you will trend toward outside
| weather. If you're in a dry climate then yeah it'll be dryer
| but the reverse is also true. Outside air is far better than
| inside nearly everywhere in the world
| newaccount74 wrote:
| Cold air can hold a lot less water vapor than warm air. If
| you open the window when it's cold outside, then the air
| will become very dry as it heats up.
|
| So even if you have 80% humidity outside on a cold winters
| day, once that air gets inside and heats up to room
| temperature it's going to be like 20% humidity.
| coding123 wrote:
| > The world is finally coming to terms with the realization that
| transmission of SARS-CoV-2 is airborne
|
| It's funny. The world is definitely a place we are willing to let
| 5 million people die. But we are definitely not allowed to have a
| single study where we have 1 definitely infected person stand in
| an air sealed room for 1 hour 6 feet away with someone not
| infected. Don't get me wrong, I have been wearing a blue 3M N95
| mask since late April 2020 while around people - but a video of
| such a study showing definitive transmission would have shut down
| the entire mask hate early.
| loloquwowndueo wrote:
| Like the mountain of evidence (videos, photos, scientific
| proof, testimony from people who have actually gone up and seen
| it) has shut up the flat earth community.
| xaduha wrote:
| > But we are definitely not allowed to have a single study
| where we have 1 definitely infected person stand in an air
| sealed room for 1 hour 6 feet away with someone not infected
|
| Why not? Studies like that are a thing. And facts don't shut
| down hate as much as you think they do.
|
| https://www.economist.com/science-and-technology/2021/09/11/...
|
| (behind paywall, but there was also free Intelligence podcast
| episode about it around that time too)
| duskwuff wrote:
| There were some rather convincing case studies even early in
| the pandemic -- for instance, one news story from March 2020
| identified a choir rehearsal as a superspreader event:
|
| https://www.latimes.com/world-nation/story/2020-03-29/corona...
| KevinEldon wrote:
| You're volunteering?
| jaspax wrote:
| I would volunteer. It turns out that I have COVID _right now_
| , giving me a mild headache, nasal congestion, and a
| persistent cough---annoying, but not more than that. I would
| have gladly volunteered for this level of mild discomfort in
| order to advance the cause of science. Wouldn't even be hard.
| Zak wrote:
| There have been human challenge studies for covid, and people
| did volunteer. It would have likely been possible to get
| volunteers for the type of study the grandparent comment
| describes.
|
| https://www.ox.ac.uk/news/2021-04-19-human-challenge-
| trial-l...
| shmel wrote:
| Come on, there are tons of people who believe that masks are
| the final answer. They should volunteer.
| jeofken wrote:
| If it's very infectious one may get it anyways. But doing it
| in the study would be virtuous, and maybe pay too. If it was
| a serious study I could do it
| the-dude wrote:
| It is rumored there have been 'infection parties'.
| adventured wrote:
| It's trivial to get volunteers. I'll volunteer. In the US
| we're around SARS2 spreaders all the time. Every time you
| spend ~30 minutes walking around in a major retail store
| chain you're highly likely to be exposed to SARS2. Now do
| that N times per week like most Americans have been for the
| past year plus. What am I supposed to be afraid of compared
| to that?
|
| I've had Covid; early into the pandemic. It was quite
| unpleasant. I'll take my chances at another round with it,
| especially if the science is quite useful and the experiment
| is reasonable.
|
| There is enormous cowardice in the governmental sphere in
| much of the world today. Otherwise we would have immediately
| began pursuing challenge trials with the mRNA vaccines, which
| took a mere few days to create. It would have been trivial to
| get thousands of volunteers to rapidly begin testing the
| vaccines and it would have been trivial to work with the
| government to stage a large physical space to do so (the army
| could have provided a significant, isolated location easily),
| at whatever cost in money and resources were necessary.
|
| In the meantime, instead, we probably had well over 100,000
| people die just in the US that didn't need to, versus had we
| accelerated the vaccine testing and deployment. Older people
| have a high vaccination rate in the US, fortunately; we could
| have gotten vaccines to them sooner. A generation or two
| prior, we would have used challenge trials to move faster.
|
| But then this is the same country that barely shrugs when
| 100,000 people die in a single year from overdoses. Of course
| that same cowardly country isn't going to do challenge
| trials.
| selimthegrim wrote:
| Imagine all those anti vaxxers' complaints about "It's
| being rushed out too quickly" and "It hasn't been studied
| yet" magnified with your proposed express schedule. Do you
| think there wouldn't have been vaccine hesitancy in those
| 100k?
| mikeyouse wrote:
| I'm not sure how you're parsing out those 100k people that
| wouldn't have died had we had vaccines earlier since we
| can't get tens of millions of people to take the live-
| saving free vaccines that have been available for nearly a
| year now.
|
| Challenge trials are fine but were hardly needed when we
| had unchecked spread of Covid for bog-standard RCTs. The
| historic speed that the vaccines made it through FDA
| approval were in large part due to the millions of active
| infections all over the country and world such that you
| could see the control vs. experimental groups very easily.
| nicoburns wrote:
| This agrees with my intuitive impression of everything I've read
| on Covid-19: that the primary transmission vector is through the
| being in unventilated or poorly ventilated enclosed spaces with
| an infected person for ~15 minutes or longer.
|
| I definitely feel like neither governmental policies or people's
| individual precautions and behaviours quite reflect that reality.
| 323 wrote:
| There have been documented cases of infections happening in
| seconds.
|
| Yes, longer exposure time increases infection probability, but
| the 15 min threshold is arbitrary, like the 2 meter social
| distancing.
|
| A bit like the "you can pick up food from the floor if it sat
| there for less than 5 seconds" meme.
| calsy wrote:
| How are infections measured in seconds?
| exclipy wrote:
| In Australia earlier this year when infections were
| happening the rate of single-digits per day, they could
| trace the source of an infection to a fleeting encounter of
| two people walking past each other in a shop.
|
| Source:
| https://www.abc.net.au/news/2021-06-22/covid19-cctv-
| footage-...
| bo1024 wrote:
| I think the person meant that it only took seconds of total
| contact time to cause an infection. Even if the infection
| took days to develop.
| anonporridge wrote:
| A potentially fantastic outcome from all this is that many more
| public and private spaces will be designed and retrofitted with
| very good ventilation.
|
| Beyond curbing the spread of natural airborne diseases, it also
| may decrease the attack vector in our societies for airborne
| bio-terrorism/warfare.
|
| And even beyond all that, we're becoming increasingly aware of
| how important clean air is for our overall health even without
| the risk of pathogens.
| mike_hock wrote:
| > it also may decrease the attack vector in our societies for
| airborne bio-terrorism/warfare
|
| Sounds extremely far-fetched. Any terrorist attack will be
| designed with the countermeasures in mind. Deploying enough
| biological agent to swamp the ventilation system would likely
| not be an issue.
| _delirium wrote:
| I hope that's true. My experience so far has been pretty
| minor symbolic changes though. My employer sent emails about
| how they swapped their MERV filters for slightly better ones,
| and something hand-wavy about adjusting the external air
| percentage "when feasible" (with no numbers). I would be
| surprised if they do major retrofits, like a new heat
| exchange system allowing significantly higher percentage of
| outside air, at least as things currently stand.
|
| I could see it happening in new buildings, though. Possibly
| in existing buildings if an easy-to-read summary number for
| ventilation became popular and the numbers for specific
| spaces became easy to find and widely publicized. Then
| companies might be willing to pay more to rent space with a
| higher "ventilation score", especially if employees balked at
| working in spaces with low scores.
| Der_Einzige wrote:
| Well, given that virus particles start to be meaningfully
| filtered only at a certain MERV level (14?), that upgrade
| may in fact have been more than a "minor symbolic" gesture.
| mlyle wrote:
| MERV-13 is pretty good. Better than 90% filtration at 1
| micrometer and up. It then comes down to how many air
| changes you can expect.
| oleganza wrote:
| Bio-terrorism you expected: some evildoers throwing dirt into
| the vents
|
| Bio-terrorism you actually got: governments using every flu
| season as an excuse to turn surveillance, police and
| paperwork up to 11 and push citizens into a neverending civil
| war of two hysterical camps.
| amelius wrote:
| Only one camp is hysterical.
| taeric wrote:
| Annoyingly, my intuitive impression is that we are still far
| more ignorant than we'd care to admit. Being in a place where
| we all willingly wear masks to grocery shop, I get the
| impression we are far more cautious than most places. Still, I
| expect it is just a matter of time before we are exposed.
|
| Why? I honestly don't know. It isn't lack of wanting to be
| safer. But it has gotten fatiguing to try to keep up with what
| makes us safer today. I remember the start when folks wiped
| down delivered groceries. Even isolated them for a few days.
| Nowadays, it seems masking is still the visible thing to do,
| but most seem pretty sure that it is the vaccination that will
| make a difference. Anything else is a slowdown, at best.
| themitigating wrote:
| Getting vaccinated, staying isolated if you are infected, and
| wearing a mask all work related to that
| duxup wrote:
| Medical policy always seems to float around various ideas
| before they really grab hold. It maybe shouldn't but it takes
| time it seems.
| delecti wrote:
| For better or worse, the medical community is usually hesitant
| to recommend things before studies have been done, and some
| "common sense" advice is difficult to test.
| bigtex wrote:
| They supported lockdown of the healthy when no major western
| country had it as a tool in their pandemic plan and
| specifically recommended against it.
| WithinReason wrote:
| Masks have been recommended heavily since the beginning
| without good evidence that they are effective. [0]
|
| https://www.medrxiv.org/content/10.1101/2020.03.30.20047217v.
| ..
|
| _CONCLUSIONS Most included trials had poor design, reporting
| and sparse events. There was insufficient evidence to provide
| a recommendation on the use of facial barriers without other
| measures. We found insufficient evidence for a difference
| between surgical masks and N95 respirators and limited
| evidence to support effectiveness of quarantine. Based on
| observational evidence from the previous SARS epidemic
| included in the previous version of our Cochrane review we
| recommend the use of masks combined with other measures._
| jonstewart wrote:
| This paper's from March, 2020?
| WithinReason wrote:
| Note that I said "since the beginning".
| ceejayoz wrote:
| Which is also incorrect; the US Surgeon General tweeted
| masks "are NOT effective in preventing general public
| from catching #Coronavirus" in Feb 2020, and Fauci said
| "There's no reason to be walking around with a mask" in
| Mar 2020. Recommendations were frequently firmly
| _against_ masking early on.
| ceejayoz wrote:
| We've had a lot more information come out since March 2020.
|
| The Bangladesh study is a particularly good one,
| demonstrating changes in disease prevalence even with less
| than half the population following masking recommendations:
| https://ncrc.jhsph.edu/research/the-impact-of-community-
| mask...
| nawgz wrote:
| Weird to pick a release from March 30, 2020. A modern
| review[0] concludes:
|
| Our review of the literature offers evidence in favor of
| widespread mask use as source control to reduce community
| transmission: Nonmedical masks use materials that obstruct
| particles of the necessary size; people are most infectious
| in the initial period postinfection, where it is common to
| have few or no symptoms (45, 46, 141); nonmedical masks
| have been effective in reducing transmission of respiratory
| viruses; and places and time periods where mask usage is
| required or widespread have shown substantially lower
| community transmission.
|
| The available evidence suggests that near-universal
| adoption of nonmedical masks when out in public, in
| combination with complementary public health measures,
| could successfully reduce Re to below 1, thereby reducing
| community spread if such measures are sustained.
|
| [0]: https://www.pnas.org/content/118/4/e2014564118
| mlyle wrote:
| I'm a teacher at a school.
|
| - We eat outside.
|
| - We have filters upgraded to MERV-13 and the fans run the
| entire school day.
|
| - We have windows and doors open on all classrooms, except for
| A) a few that don't open outside, or B) when it's rainy/windy
| to the point it's not possible. We have small, secondary HEPA
| filters that we run in those circumstances. (Often, we're
| blaring AC or heat into a room with all doors and windows open
| just to get a few degrees closer to comfort).
|
| - We mask indoors, too.
|
| So far, no secondary cases attributable to spread at school.
| We've had frequent testing for much of the time, too, so they'd
| likely get detected. Now a lot of the student body is
| vaccinated, too, but this dates to before that.
| jaimex2 wrote:
| Explains Queensland doing so well here in Australia thinking
| about it. Everything is built with high ventilation flow in mind.
___________________________________________________________________
(page generated 2021-11-28 23:01 UTC)