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A paradigm shift to combat indoor respiratory infection

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Re: A paradigm shift to combat indoor respiratory infection

#11

Post by londons_explore »

colechristensen wrote: post #8

It seems overly complicated. Just raise the air exchange per person and or per volume by a significant factor and mandate a very fine particulate filter. You could do many measurements and lots of theory but nobody is going to engineer their buildings like cleanrooms anyway so the results of a lot of science wouldn’t be so good regardless.

I'd like to see "air quality inspection" be part of a fire safety inspection.

Just have the inspector crack out a CO2 and PM2.5 meter during the inspection. Set legal limits and have a fee for exceeding them. Make it apply to existing buildings too, so building owners can choose to trade off increased HVAC costs Vs reducing the fee Vs costs of retrofitting better ventilation.

Obviously the measured numbers vary a lot day to day, so if a building owner isn't happy with values measured on the day, let them take an average over a week or something.

Re: A paradigm shift to combat indoor respiratory infection

#12

Post by shalmanese »

colechristensen wrote: post #8

It seems overly complicated. Just raise the air exchange per person and or per volume by a significant factor and mandate a very fine particulate filter. You could do many measurements and lots of theory but nobody is going to engineer their buildings like cleanrooms anyway so the results of a lot of science wouldn’t be so good regardless.

That has significant costs on the energy efficiency of buildings and would blunt a lot of the progress we're making on combating climate change.

Not saying it shouldn't be done but it should be done in a smart way that balances between tradeoffs.

Re: A paradigm shift to combat indoor respiratory infection

#13

Post by londons_explore »

prof-dr-ir wrote: post #7

From the article: "It is not known exactly what fraction of infections could be prevented if all building and transport ventilation systems on the planet were ideal (in terms of controlling airborne infections), or the cost of design and retrofitting to make them ideal." I think this is the key question. Surely better ventilation would have prevented some infections in the covid pandemic. But how many? And to decide…

I would put money on COVID not happening at all if all buildings had 10 air refreshes per hour, and that air either coming from the outdoors or going through a HEPA filter.

I would guess an analysis of workplace COVID rates would see a strong correlation between workplaces with and without filtration in their AC systems.

Re: A paradigm shift to combat indoor respiratory infection

#14

Post by lostmsu »

shalmanese wrote: post #12
colechristensen wrote: post #8

It seems overly complicated. Just raise the air exchange per person and or per volume by a significant factor and mandate a very fine particulate filter. You could do many measurements and lots of theory but nobody is going to engineer their buildings like cleanrooms anyway so the results of a lot of science wouldn’t be so good regardless.

That has significant costs on the energy efficiency of buildings and would blunt a lot of the progress we're making on combating climate change. Not saying it shouldn't be done but it should be done in a smart way that balances between tradeoffs.

Does it? I thought energy expenditure to maintain indoor temperature is mostly due to heating/cooling, not due to moving air to or from heat exchanger. E.g. it is cheap to rotate the air in the building in a closed loop through a filter.

Re: A paradigm shift to combat indoor respiratory infection

#15

Post by Robin_Message »

shalmanese wrote: post #12
colechristensen wrote: post #8

It seems overly complicated. Just raise the air exchange per person and or per volume by a significant factor and mandate a very fine particulate filter. You could do many measurements and lots of theory but nobody is going to engineer their buildings like cleanrooms anyway so the results of a lot of science wouldn’t be so good regardless.

That has significant costs on the energy efficiency of buildings and would blunt a lot of the progress we're making on combating climate change. Not saying it shouldn't be done but it should be done in a smart way that balances between tradeoffs.

You can use heat exchangers between outlet and inlet air to mitigate a good portion of the energy cost I believe.

Re: A paradigm shift to combat indoor respiratory infection

#16

Post by disabled »

colechristensen wrote: post #8

It seems overly complicated. Just raise the air exchange per person and or per volume by a significant factor and mandate a very fine particulate filter. You could do many measurements and lots of theory but nobody is going to engineer their buildings like cleanrooms anyway so the results of a lot of science wouldn’t be so good regardless.

> Just raise the air exchange per person and or per volume by a significant factor and mandate a very fine particulate filter.

An alternative in the meantime is to use a PAPR (powered air purifying respirator), which are more efficient, last much longer (device and filter), and are much more comfortable than N95 masks. I use an Optrel Swiss Air and cover the valves of the mask with a hoodie style balaclava.

It would be a good time to get one, as it is believed that it is only a matter of time before SARS-CoV-2 mutates into a variant that is capable of evading the vaccines.

Also, the US CDC advice may not have been such a good idea. Look at these calculations:

https://twitter.com/DrEricDing/status/1393090966928637952?s=...

Singapore has a comparable vaccination rate to the US and is going into lockdown to prevent further spread. They used Pfizer and Moderna vaccines. Just some food for thought:

https://twitter.com/andrewkimmel/status/1393086704349630464?...

Re: A paradigm shift to combat indoor respiratory infection

#17

Post by _y5hn »

zargon wrote: post #9
prof-dr-ir wrote: post #7

From the article: "It is not known exactly what fraction of infections could be prevented if all building and transport ventilation systems on the planet were ideal (in terms of controlling airborne infections), or the cost of design and retrofitting to make them ideal." I think this is the key question. Surely better ventilation would have prevented some infections in the covid pandemic. But how many? And to decide…

The WHO and CDC have had their head in the sand for 60 years when it comes to airborne pathogens. They have only acknowledged aerosol transmission of covid in the last couple weeks. It was physicists who had to figure out why they were domatically denying reality. https://www.wired.com/story/the-teeny-tiny-scientific-screwu...

Good to expose such expert arrogance.

Re: A paradigm shift to combat indoor respiratory infection

#18

Post by _y5hn »

londons_explore wrote: post #13
prof-dr-ir wrote: post #7

From the article: "It is not known exactly what fraction of infections could be prevented if all building and transport ventilation systems on the planet were ideal (in terms of controlling airborne infections), or the cost of design and retrofitting to make them ideal." I think this is the key question. Surely better ventilation would have prevented some infections in the covid pandemic. But how many? And to decide…

I would put money on COVID not happening at all if all buildings had 10 air refreshes per hour, and that air either coming from the outdoors or going through a HEPA filter. I would guess an analysis of workplace COVID rates would see a strong correlation between workplaces with and without filtration in their AC systems.

The highest infection rates are still short range though. This, combined with being a new virus would still be similar to today.

Re: A paradigm shift to combat indoor respiratory infection

#19

Post by newsbinator »

zargon wrote: post #9
prof-dr-ir wrote: post #7

From the article: "It is not known exactly what fraction of infections could be prevented if all building and transport ventilation systems on the planet were ideal (in terms of controlling airborne infections), or the cost of design and retrofitting to make them ideal." I think this is the key question. Surely better ventilation would have prevented some infections in the covid pandemic. But how many? And to decide…

The WHO and CDC have had their head in the sand for 60 years when it comes to airborne pathogens. They have only acknowledged aerosol transmission of covid in the last couple weeks. It was physicists who had to figure out why they were domatically denying reality. https://www.wired.com/story/the-teeny-tiny-scientific-screwu...

> EARLY ONE MORNING, Linsey Marr tiptoed to her dining room table, slipped on a headset, and fired up Zoom. On her computer screen, dozens of familiar faces began to appear. She also saw a few people she didn’t know

It’s really hard for me to read a WIRED article for information.

I mean I realize that’s not what it’s there for but it takes forever to get into the content of the article.

Re: A paradigm shift to combat indoor respiratory infection

#20

Post by dalyons »

disabled wrote: post #16
colechristensen wrote: post #8

It seems overly complicated. Just raise the air exchange per person and or per volume by a significant factor and mandate a very fine particulate filter. You could do many measurements and lots of theory but nobody is going to engineer their buildings like cleanrooms anyway so the results of a lot of science wouldn’t be so good regardless.

> Just raise the air exchange per person and or per volume by a significant factor and mandate a very fine particulate filter. An alternative in the meantime is to use a PAPR (powered air purifying respirator), which are more efficient, last much longer (device and filter), and are much more comfortable than N95 masks. I use an Optrel Swiss Air and cover the valves of the mask with a hoodie style balaclava. It would…

. Singapore is at 31% one shot(from your link), US is at 47 and rising. Of course you would still be able to get spikes in cases at only 31%, that’s expected.

The mRNA vaccines are stupendously effective at stopping all variants thus far. Not sure what evidence aside from fear point to covid being able to mutate past them.

We good, and it’s ok to accept that and have hope, not everything has to be fear-for-the-worst

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