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Real-world data show that filters clean Covid-causing virus from air

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Re: Real-world data show that filters clean Covid-causing virus from air

#101

Post by drzaiusapelord »

nprz wrote: post #74

Someone made an interesting point that we got rid of cholera by drinking cleaner water and that we'll get rid of Covid by breathing cleaner air.

You won't often catch covid from stray particles but from the person breathing next to you, which these filters can't help. This study was in a hospital where everyone is wearing serious PPE, so its a super edge case to get rid of covid in the air because the main use case of catching covid has been handle by plain old PPE.

This doesn't have sweeping applicability. It won't stop covid among the general population. Its for maybe hospitals that are on super covid lockdown that want a little more protection for their most vulnerable patients.

We get rid of covid through mass vaccination like any other virus. There's no shortcuts for those who refuse masks and vaccines.

Re: Real-world data show that filters clean Covid-causing virus from air

#102

Post by amluto »

im_down_w_otp wrote: post #38
Wowfunhappy wrote: post #35

Earlier quoted context omitted.

I'm student teaching in a third grade classroom, and I want to add a least a small counter: We are required to have two HEPA filters always running in the classroom. They are loud. Combined with the fact that (1) children mumble, (2) the children have masks on, and (3) everyone is supposed to stay 3+ feet apart, it's quite hard to hear what a lot of kids are saying! I don't know what the right answer is, but what we…

The point would be to have the central HVAC system be renovated to boost circulation with HEPA filters in the loop precisely so that you don't have to have two noisy things doing a middling job of a similar task in the classroom itself.

Or upgrade to MERV 16, which is nearly as good, much cheaper, and has much lower pressure loss.

Re: Real-world data show that filters clean Covid-causing virus from air

#103

Post by DoingIsLearning »

> Hospitals have turned to portable air filters as an attractive solution when their isolation facilities are full.

Woah! I knew that isolation rooms where full-on filtered and with positive pressure. But I genuinely believed that all hospital HVAC units and major circulation ducts had HEPA filter stages.

Is this true? Is it not mandatory for hospitals to add these filtering stages on all HVAC units or circulation ducts?

Do they really just keep rotating the same contaminated air throughout the whole hospital?

Re: Real-world data show that filters clean Covid-causing virus from air

#104

Post by DonHopkins »

drzaiusapelord wrote: post #101
nprz wrote: post #74

Someone made an interesting point that we got rid of cholera by drinking cleaner water and that we'll get rid of Covid by breathing cleaner air.

You won't often catch covid from stray particles but from the person breathing next to you, which these filters can't help. This study was in a hospital where everyone is wearing serious PPE, so its a super edge case to get rid of covid in the air because the main use case of catching covid has been handle by plain old PPE. This doesn't have sweeping applicability. It won't stop covid among the general population. It…

>There's no shortcuts for those who refuse masks and vaccines.

Just urns and gravestones.

Re: Real-world data show that filters clean Covid-causing virus from air

#105

Post by Pxtl »

nprz wrote: post #74

Someone made an interesting point that we got rid of cholera by drinking cleaner water and that we'll get rid of Covid by breathing cleaner air.

"air is the new poop" is what public health dr David Fisman says... Which is hyperbolic but succinct.

Re: Real-world data show that filters clean Covid-causing virus from air

#106

Post by DonHopkins »

I recently posted a description of a powerful cooling fan I set up for my MacBook Pro that I'm thinking of adding a filter to. I wonder if the inline duct fan I got is strong enough for HEPA filters. It's a lot stronger than a box fan. It runs off of AC and has a speed adjustment control. The TD-500/150-160 moves 550 m^3/hour at 2480 rpm.

https://www.solerpalau.com/nl-nl/ronde-buisventilator-td-sil...

https://statics.solerpalau.com/media/import/documentation/NL...

Here are some centrifugaal high pressure tube fans, but I don't know how noisy they are compared to the S&P "TD-SILENT" silent series (with noisy sounding names like "Cyclone").

https://www.ventilatieshop.com/buisventilatoren/hogedruk-bui...

https://news.ycombinator.com/item?id=28736187

The overheating problem on my MBP was so bad and so pathetically common, that I had to take drastic and expensive measures, which work pretty well. I tried various laptop cooling stands, and they were cheap and plastic and had shitty fans that hardly pushed any air, and didn't help.

So I got a solid aluminum laptop stand without a fan, which conducts heat much better than plastic, and I bought four sets of stick-on heat sinks (some large and some small), and stuck them all over the back of the aluminum laptop stand on the surface that touches the bottom of the laptop.

Then I bought a very powerful and quiet inline ventilation fan (the kind you use to pump air out of the bathroom), and analog speed dial (make sure you get an AC speed control for an AC fan, or a DC control if you get a DC fan) and some big wide round air tubing, and I set the fan in the opposite corner of the room (or outside the room with the door open) where the noise it generates is harder to hear, and ran the tube up to the cooling-fin encrusted back of the laptop stand, where it quietly blows lots of air on the back, and cools the stand and laptop quite effectively.

I usually run it at the lowest quietest setting "1", but can turn it up to "10" to cool it down quicker when it's overheating.

If anyone's interested I can provide links to the actual products I bought. Desktop and laptop fans were just not powerful enough, and very loud and clumsy, and it sucks to have the fan itself right next to you instead of in the next room. But the inline room ventilation fans are much more powerful and quieter and adjustable, but more expensive, and the flexible air tube lets you position the fan far away from the computer.

I was losing so many hours of work due to overheating that it was well worth investing in all the equipment to really cool it down.

Here are the small and large adhesive heat sinks, which are sold for 3d printers (I got two packs of each size: 16 eur total for 40 small ones, 16 eur total for 8 big ones):

CTRICALVER Aluminium Heatsink, Black Heatsink, Thermal Adhesive Pad Cooler, for 3D Printer, Pack of 10 (20pcs)

CTRICALVER Thermal conductivity of the radiator, heat conduction measures L40 mm x W40 mm x H11 mm, pack of 4

The fan was 185 eur, and the AC speed control was 35 eur or so, and I wired it myself with a switched plug for a couple euros. There are many models of fan, some AC and some DC, that move various amounts of air per minute, with fixed or three or variable speeds, that make different amounts of noise, but I shopped around and am pretty happy with the mid-range one I got. (S&P is a European brand so YYMV.)

Soler & Palau TD-500/150-160 Silent 580/430m3 Air Conditioning Fan + REB-1N AC speed control

The aluminum stand was 36 eur:

NULAXY Laptop Ständer, Einstellbar Notebook Ständer, Ausblendbar laptopständer Kompatibel für alle 11-17 inches Notebooks: MacBook Pro/Air, Dell

The next step I'm planning is making an air filteration system by taping together some filters like this DIY box fan air purifier, but using the powerful inline fan instead of a weak box fan:

https://tombuildsstuff.blogspot.com/2013/06/better-box-fan-a...

I haven't decided what kind of filters to use yet: cheap high flow central air conditioner filters, or more expensive HEPA filters, that restrict the air flow more. The fan is quite powerful so I'm pretty sure it can handle the HEPA filters, but I haven't tried yet. Maybe that's overkill. But after wasting so many hours on overheating, overkill is kind of the point.

Re: Real-world data show that filters clean Covid-causing virus from air

#108

Post by Etherlord87 »

0xdeadb00f wrote: post #107

What's the deal with "covid-causing virus" in the title? Is there some kind of virus relationship ala HIV/AIDS that I wasn't aware of?

COVID-19 is the name of the disease caused by SARS-CoV-2 virus.

https://en.wikipedia.org/wiki/COVID-19 https://en.wikipedia.org/wiki/Severe_acute_respiratory_syndr...

Re: Real-world data show that filters clean Covid-causing virus from air

#109

Post by vondur »

drzaiusapelord wrote: post #101
nprz wrote: post #74

Someone made an interesting point that we got rid of cholera by drinking cleaner water and that we'll get rid of Covid by breathing cleaner air.

You won't often catch covid from stray particles but from the person breathing next to you, which these filters can't help. This study was in a hospital where everyone is wearing serious PPE, so its a super edge case to get rid of covid in the air because the main use case of catching covid has been handle by plain old PPE. This doesn't have sweeping applicability. It won't stop covid among the general population. It…

What if the air is being actively refreshed and filtered. I believe this is what needs to start happening in most indoor environments. This would definitely help with reducing the amount of cases.

Re: Real-world data show that filters clean Covid-causing virus from air

#110

Post by user743 »

DonHopkins wrote: post #104
drzaiusapelord wrote: post #101

Earlier quoted context omitted.

You won't often catch covid from stray particles but from the person breathing next to you, which these filters can't help. This study was in a hospital where everyone is wearing serious PPE, so its a super edge case to get rid of covid in the air because the main use case of catching covid has been handle by plain old PPE. This doesn't have sweeping applicability. It won't stop covid among the general population. It…

>There's no shortcuts for those who refuse masks and vaccines. Just urns and gravestones.

Or an immune system... or therapeutics...
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