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Zenst

Not surprising as many air conditioning units don't filter the air at the level required to remove viral agents.

Also been reports about them and virus's in the past.

But more recently https://www.telegraph.co.uk/news/2020/03/06/air-conditioning...

But like many things, even common sense needs the data to back it up so people take note.

Coz we have had experts in the field of air-con say they don't, and also experts say they do:

https://www.straitstimes.com/singapore/health/coronavirus-tu...

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Office buildings I've worked at in the past barely had any filtration. Within a few days, the untouched parts of your desk would have a layer of dust on it. I'm now (well, not now-now since everyone is WFH) in a LEED Gold building and the filtration is much better, and I only have to clean the monitors every 5 or 6 weeks.

As good as it is, it still won't catch virus sized particles - that's a biosafety level 3 or 4 facility (like in Andromeda Strain) and you're not going to find that in an commercial building.

Coronavirus requires droplets to spread. Those droplets can be very small, and carry a ways through the air (which is what this article is proposing, not that the virus was carried through the ducting), but they are orders of magnitude bigger than the virus itself, and would absolutely be caught by a typical filter.

There are viruses that can spread that way. Measles, for instance, is known for doing that. Coronavirus can't (as far as anyone knows, and we know quite a lot about that).

>that's a biosafety level 3 or 4 facility As dramatic as that sounds, you can get commercial and home aircons that will filter at the level to kill or remove viruses.

Though for COVID-19 you would want something that can filter at 0.125 micron as that is the size of this virus.

They're not saying the virus went through the AC, but that the stream of air leaving the AC likely blew the virus from one downstream table to another.

Yes, though the point being that most will not filter out the air that does pass thru them enough to remove any virus level material in the airstream. Hence if they went in in/out or just got blown about by the aircon, it would make no difference to the virus due to its size.

Did you read the abstract? It explains a theory of how the movement of droplets throughout the restaurant is consistent with the airflow from the air conditioner. Nothing to do with filters.

Yes, did you read my comment about having read many papers about this in the past?

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