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Why don’t we just open the windows? Covid-19 prevention lost in translation

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Re: Why don’t we just open the windows? Covid-19 prevention lost in translation

#181

Post by dboreham »

chmod600 wrote: post #168
nr2x wrote: post #151

Earlier quoted context omitted.

To add to that - younger children are really good with mask wearing in my experience - which is a big factor compared to the teenagers who ditch the mask as soon as no authority figure is in sight...or the adults with the maturity level of teenagers.

Does weaing a mask so often have downsides? I'm not "anti-mask". I'm just wondering whether we will see studies in 10-20 years about a bunch of children with lung problems from restricted airflow or weird fibers or chemicals, or other pathogens that grew on the masks, or something we haven't thought of yet. Or who knows? Maybe kids will all have super strong lungs. Or maybe lucky ones will have stronger lungs and oth…

Like the surgeons who have been dropping like flies for the past 100 years because they wear masks all day at work?

Re: Why don’t we just open the windows? Covid-19 prevention lost in translation

#182

Post by dannyw »

tapan_jk wrote: post #155
IG_Semmelweiss wrote: post #12

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.

I used to prefer Uber/Ola over the humble auto rickshaw [1] mainly because of two reasons: cars are safer; and an air-conditioned car helps avoid pollution from traffic (which is quite high in Bangalore). Now I prefer auto rickshaws (at least for short distances) because they are well ventilated due to its door-less design. The back seat of an auto rickshaw is constantly braving the elements (sunlight, dust and wind)…

I'm fully vaccinated and also got mild COVID once, so as someone in my 20s with no underlying health conditions, I don't really care about ventilation anymore.

Re: Why don’t we just open the windows? Covid-19 prevention lost in translation

#183

Post by hanniabu »

jhugo wrote: post #125
ajmurmann wrote: post #103

Earlier quoted context omitted.

To be clear, I'm very much in favor of hand washing and have been using hand sanitizer whenever I come home since we'll before the pandemic. It helps with other infectious diseases, but I wonder about COVID

Washing your hands properly with soap and water is much more effective than hand sanitiser in typical use. Hand sanitiser is most useful when you don't have convenient access to soap and hot water. Since you're arriving home anyway, you might as well wash your hands properly — the skin on your hands will thank you for one less exposure to hand sanitiser, too.

Hand sanitizer is more effective than your average person's hand washing practices, which is pretty poor

Re: Why don’t we just open the windows? Covid-19 prevention lost in translation

#184

Post by dboreham »

mlyle wrote: post #167
jkhdigital wrote: post #124

Earlier quoted context omitted.

It’s not like you can see the viral particles jumping over in that exact moment. I’m sure there is more to the story, but let’s not try and claim that this is incontrovertible scientific proof that infection happens “in seconds”.

If: * A vast majority of infections can be traced * You have an infection whose only traceable contact is for a few seconds in a store... It seems pretty likely that the infection happened in the moments surrounding those few seconds. Especially when we have multiple circumstances like this. Especially when it agrees with our underlying understanding of the germ theory of disease. Extended contact makes infection muc…

Not necessarily. I'd be interested to know if the virus samples from those two people were sequenced in order to prove transmission from one to the other. Absent that evidence there could be other explanations such as : transmission was from some third person not known to the contact tracers.

Re: Why don’t we just open the windows? Covid-19 prevention lost in translation

#185

Post by BoorishBears »

sillysaurusx wrote: post #180
willyt wrote: post #72

> Pumping in adequate amounts of fresh outside air, however engineered, will challenge running costs as well as carbon status. This is wrong. Mechanical Heat Recovery Ventilation (MVHR) is a well established technology which can recycle 96% of the heat from the waste air in a house. It costs about the same to fit as a central heating system. Passive houses have very high Air Changes per Hour (ACH) compared to convent…

It sounds like they were referring to cooling air, not heating it. Is there an energy-efficient strategy for that? If not, then it doesn't seem like they were mistaken, just imprecise.

It's the same system.

Heat recovery works both ways, maintaining heat out the outlets or maintaining heat at the inlets

Re: Why don’t we just open the windows? Covid-19 prevention lost in translation

#186

Post by Gigachad »

aspaceman wrote: post #95
doubled112 wrote: post #62

Earlier quoted context omitted.

My kid's school doesn't have windows that open. It's too new for that.

Is that really a newer thing? My ancient high school had 45-degree windows (for theft and suicide prevention I imagine). Why lock it all down? Cost?

When I worked in an office, they had all of the windows screwed in to prevent opening to comply with new building codes. I imagine for suicide and accident prevention. It looks like these days you can only have windows that wind out a little. My apartment has these, but it also has an option on the AC controls to bring outside air in which can force ventilation if it isn't windy outside.

This is mostly for tall buildings though. For a school, it could be that they want to be able to control the airflow and AC. Having a window open could be letting out the heat causing the heating to work harder for no reason.

Re: Why don’t we just open the windows? Covid-19 prevention lost in translation

#187

Post by chrismorgan »

mlyle wrote: post #102
aspaceman wrote: post #95

Earlier quoted context omitted.

Is that really a newer thing? My ancient high school had 45-degree windows (for theft and suicide prevention I imagine). Why lock it all down? Cost?

It's a LEED rating thing. If you can rely upon windows entirely for ventilation and thermal control, that's great. Otherwise, windows that open leak more air when you don't want them to. They also let in more humid air, which in turn has a higher specific heat capacity and requires more energy to dry the air later. Their usage tends to be uneven, so you often have open windows while AC is also running elsewhere or in…

More humid air with higher specific heat capacity: I’d expect the difference to be utterly negligible. Even at 40°C, the isobaric heat capacity of saturated air is only about 5% higher than that of perfectly dry air (~1.05 J/g·K, compared to ~1), and your slightly leaky window is hardly going to be resaturating the entire room.

As for the energy to dry the air, I’m inexpert in this area¹ but under the impression dehumidification is essentially just a byproduct of how compressors work (the evaporator’s low temperature causes water vapour to condense) rather than something that takes deliberate effort—that, if anything, air conditioners are commonly now deliberately revapourising water to avoid dehumidification beyond the desired level.

—⁂—

¹ But I am trying to learn for part of a project of my own, a velomobile and trailer to be able to live out of indefinitely, where in the ideal case that I haven’t determined is feasible I’d really like it if I could have one compressor to drive food refrigeration, cabin cooling, heating a low-temperature slow-cooker-style oven, and providing my water supply.

Re: Why don’t we just open the windows? Covid-19 prevention lost in translation

#188

Post by sillysaurusx »

BoorishBears wrote: post #185
sillysaurusx wrote: post #180

Earlier quoted context omitted.

It sounds like they were referring to cooling air, not heating it. Is there an energy-efficient strategy for that? If not, then it doesn't seem like they were mistaken, just imprecise.

It's the same system. Heat recovery works both ways, maintaining heat out the outlets or maintaining heat at the inlets

That's interesting. It's tempting to think that if we build houses in slightly different ways, we could have energy efficient heating and cooling systems. It seems like humidity might be a problem.

Re: Why don’t we just open the windows? Covid-19 prevention lost in translation

#189

Post by dboreham »

Izkata wrote: post #150
coolso wrote: post #71

Earlier quoted context omitted.

> Imagine all those anti vaxxers' complaints about "It's being rushed out too quickly" and "It hasn't been studied yet" Listen, CNN [0] and Biden [1] changed their mind about all of that as soon as the election was over, so don’t be too hard on them. [0] https://www.cnn.com/2020/09/01/health/eua-coronavirus-vaccin... [1] https://www.nytimes.com/2020/09/16/us/politics/biden-trump-c...

As much as the flagged sibling comment looks like a flippant joke, it's true: a few weeks ago I saw a posted image of a new school textbook that, in the "recent history" section, altered the timeline to make it look like the Biden administration had a hand in creating the vaccines, rather than Trump's Operation Warp Speed.

Creating, or distributing?

Re: Why don’t we just open the windows? Covid-19 prevention lost in translation

#190

Post by neilwilson »

jkhdigital wrote: post #117
mlyle wrote: post #48

Earlier quoted context omitted.

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 wi…

So let me ask you: with such well-ventilated facilities, what is the marginal benefit of masking? And is this benefit worth the difficult-to-quantify but very real cost of students being unable to see the faces of their classmates?

Masking is a psychological process designed to install compliance. If it was designed to prevent illness you would insist on using the correct sort of mask that filters inbound - since that protects you from failures elsewhere.

I would hope that nobody here would ever design a process that requires 100% compliance to very strict criteria before it has a chance of doing what it is supposed to do. Particularly when there is an obvious and clearly superior alternative that works regardless of what others do.

The whole process we have in place at moment is backwards from a physics point of view - filters under pressure leak, and don't under suction.

Ask yourself why massive studies didn't happen with tightly controlled experiments in normal real world situations where changing masks was the only variable altered. We've had eighteen months to do such work and yet apparently we can't organise it in an unequivocal fashion.

Instead we get people trying to use statistical methods to stitch together alleged proof. Which then leads to reporting bias as cognitive dissonance kicks in.

It's like watching the diet-heart hypothesis again in real time. That took 40 years before it was abandoned.

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