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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

#191

Post by IgorPartola »

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…

The only issue I have seen so far is that constantly exhaling onto your eyes dries them out and can make them more prone to minor infections. Happened to me, doctor told me to not use contacts for a bit and take mask breaks once in a while. Outside of that, medical professionals wear masks all the time. Nurses are often subjects of medical studies because they are an accessible caprice audience. I know of no known cases of mask wearing being a bad thing.

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

#192

Post by mlyle »

dboreham wrote: post #184
mlyle wrote: post #167

Earlier quoted context omitted.

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.

> transmission was from some third person not known to the contact tracers.

This becomes an unlikely explanation once

> > * A vast majority of infections can be traced

and

> > Especially when we have multiple circumstances like this.

The probability of an alternate explanation becomes exceptionally unlikely. It's further reduced by our general scientific understanding that:

> > But people who are sick shed live virus, and there's not a safe level of exposure of live virus where infection is impossible.

Infection from a momentary contact is fairly unlikely. But when you have a massive number of momentary contacts in the populace, it happening many times becomes a near certainty.

E.g., this:

> Several individuals in Australia were also infected with the Kappa variant through lingering virus aerosol particles in the hallway of a quarantine hotel in May. Though the individuals had no direct contact with each other they opened the doors to their hotel rooms within 30 minutes of each other and tested positive for the same strain.

No complete sequencing, but the same variant... spread several times apparently by the same mechanism of indirect contact, several individuals infected. In a quarantine hotel, where there's not many alternate explanations available.

Or this one, confirmed by sequencing:

> A similar event occurred earlier in April where two families quarantining in rooms next to one another were found to share the same viral sequence, after briefly opening their doors 30 minutes apart.

https://www.forbes.com/sites/williamhaseltine/2021/06/28/inf...

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

#193

Post by hardwaregeek »

The plastic barriers that have become so common are an egregious example of this. They hurt air circulation and don't prevent transmission, but they're cheap and appear to do something. I've wondered why restaurants haven't started using some sort of fan attached to a high quality air filter, basically a cheap air purifier. And for more intensive usecases, why not have chambers that are sealed off and have a powered filter as the intake? I'm not the expert here so there's probably a good reason why, but it was a little weird seeing everybody focus on ventilators at the beginning of the pandemic instead of filtration.

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

#194

Post by sp332 »

dboreham wrote: post #181
chmod600 wrote: post #168

Earlier quoted context omitted.

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?

They get new masks every few hours. Or they did before the pandemic anyway.

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

#195

Post by andi999 »

Eelongate wrote: post #96
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…

In much of the world for much of the year, it doesn't get below freezing for at least part of the day. The solution to the heating problem is simple then: simply don't. Open windows when it's above 50F / 10C (to give a healthy safety margin to the water pipes) and tell people to wear sweaters. Do this where it's possible and you'll offset the energy expenditure of heating in places were it actually earnestly gets col…

Do you live in a non tropical region?

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

#196

Post by helsinkiandrew »

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…

The article is about transmission of SARS-CoV-2 in our existing environment. Not about how to build cool/heat buildings.

How many buildings have MHRV now? or could install MHRV without replacing or adding to their current heating/cooling system before it needs to be replaced - which would "challenge running costs as well as carbon status" for the next few years or more.

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

#198

Post by jmspring »

hardwaregeek wrote: post #193

The plastic barriers that have become so common are an egregious example of this. They hurt air circulation and don't prevent transmission, but they're cheap and appear to do something. I've wondered why restaurants haven't started using some sort of fan attached to a high quality air filter, basically a cheap air purifier. And for more intensive usecases, why not have chambers that are sealed off and have a powered…

Didn’t read the article? But in the US inside there aren’t plastic barriers. There will be no updating of hvac systems. I’m pro mask indoors, but favor places that are pro vaccine card. WA and OR were more appropriate to this than CA.

You will not, outside super heavy government subsidy, get better interior filtration in the US.

I say this as a business owner who could probably persuade the building owner to offset part of the charge, but the cost doesn’t make sense.

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

#199

Post by mhb »

IG_Semmelweiss wrote: post #20
bb123 wrote: post #13

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.

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 wi…

Any common sense organization would be strongly suggesting that people wear N95 masks with vents (more comfortable) to protect themselves. But here we are - still wearing whatever we can find around the house.

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

#200

Post by mlyle »

chrismorgan wrote: post #187
mlyle wrote: post #102

Earlier quoted context omitted.

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 dehu…

> More humid air with higher specific heat capacity

OK, so I should add a little more nuance:

* With more water vapor in the air, the air has a little more heat capacity

* With more water vapor in the air, the temperature band for comfort is a little narrower

* With more water vapor in the air, air conditioners need to work extra hard to provide the same cooling.

That is, the more water there is in the air to begin with, the more will condense and return its heat of vaporization to the room.

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