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I am not convinced we'll see long-term spatial consequences from covid itself. From the economic consequences, that sounds more plausible.
If the ICC is paying attention, we will see more consequences in the design of ventilation.

I am fascinated by this detail in the SARS epidemic, where SARS viruses were aerosolized in toilets and then spread back through bathroom floor drains.… Image
This says that the transmission required small bathrooms, negative ventilation pressure, and dry traps in the floor drains.

Most US apartment bathrooms don't have floor drains and a lot vent separately, so IDK about this pathway here. But...
... a lot of our bathrooms fans only run when occupied. I wonder if inadequate flow and pressure differences could divert some aerosolized particles from one bathroom to another. Not a mechanical engineer, but I have to wonder.
Additionally, this study found that the buildings around that the first building saw increased SARS cases soon after the aerosolized spread began, which suggests spread via some kind of vent.…
Sewer vents are as old as indoor plumbing, and unfortunately, they're even on the detached single family piece of heaven next door.

Again, I am not a scientist or engineer, I just want scientists to look at these sites.
So it sounds like, according to this press conference, PTACs will play a critical role in the Army Corps's emergency covid hospitals?…
Please share a link if you find the design. Based on what I shared upthread, I hope they consider how to filter the toilet exhaust. I am not sure how this is done in hospitals.
Just like every other building, a thin plastic membrane is a key part of managing the building's atmospheres.
Also based on that description, a lot of 5/1s with facade exhausts also probably would work, plus you'd get laundry and granite countertops.
Enjoying this contraption used to test whether flu and coronaviruses can be aerosolized Image
Bored by airflow and want to stick to surfaces? Here’s how to clean Coronavirus off historic stuff:
Besides issuing masks to employees—three weeks ago better but now is good too—It sounds like the MTA needs to study airflow in cars and stations too. For the flu, for example.
Some regulator is gonna take a long hard look at these problems and conclude the only thing to do is make the mezzanines larger.
Unreviewed study in China claims that "mobile toilets" and staff PPE removal rooms had high levels of airborne virus, unlike negative pressure rooms.…
“A one-off pandemic usually has no impact at all,” says Lynteris.…
Of course it could, if we decided to learn from it. It’s a good article.
One thing that struck me is that the desire for solutions goes back to the idea of conditioning the environment, conditioning our atmosphere, which is way costlier than conditioning our bodies with clothing or masks. We pay more for convenience and comfort of course.
This study could use the input of a mechanical engineer (what kind of a/c, what is the airflow, does it have a filter, etc.) but it presents interesting implications for hygienic design.
This pre-review version has a measurement-informed CFD model of recirculation and identifies the units as fan coils. Photos would still be useful.… Image
ASHRAE has guidance now - not qualified to assess it but it is interesting. Homes:…
This article summarizing a letter from Passive House engineers is worth looking at - they target all forms of recirculation, including zoned VAVs like most offices, and fan coils, i.e. wall units.…
The addendum is interesting. DOAS - conditioning only fresh air, and heating/cooling locally - is what we used on AGU, but often require fan coils or local recirculating VRFs in the US. Not sure where that gets you.
He mentions displacement ventilation, and I wonder if he is including underfloor distribution, meaning thicker slabs. Difficult to see how underfloor distribution, radiant panels, or dual-duct DOAS can become common in DC with the Height Act as it stands.
We need to know what kind of air conditioning system the building had, and how it was zoned before getting excited.
With all the talk about putting UV-C lights in ducts, I hope thought is put into maintenance practices. We don't want a bunch of facilities guys going blind when they change the air filters.
I read a few studies about aerosolization of the 'rona that use something called a Goldberg Drum, which is this thing below, designed to isolate *decay* of the virus from just falling out of the air. Something to look for when there's news about airborne duration. Image
Study out of China finds crazy infection rates in a coach bus and conference room with recirculating air. (4ACH in the latter example)…
One thing I would like to see is analysis by total air volume per occupant. Like, allegedly planes have higher air exchange than an office but each person gets a lot less air, so... are you more likely to be breathing pre-breathed air?
Personal Cooling Devices are my unrealistic crank cause, and it’s their moment.
Pre-review analysis from the World Bank links the local extent of infection to PM2.5 particulate emissions, controlling for density.…
Inference is based on studies of other viruses. Obvious environmental justice implications. Looks at outdoor air but PM2.5 is often worse indoors. Image
Not sure these ideas are all that informed by science. We know elevators aren’t big sources of spread, but open offices are. But a sink in the lobby? Probably wise.…
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