Discover and read the best of Twitter Threads about #CorsiRosenthalBox

Most recents (24)

Here’s the most COVID song ever, In The Air Tonight, on the RGB CR Box tower of power. All fans are CR Boxes. I don’t think it makes it to the “climax” of this song so I might have to post part 2. #corsirosenthalbox
Part 2, with the drum roll! @LazarusLong13 @JimRosenthal4 @robwiss
BTS so you can see they are in fact CR Boxes! ImageImage
Read 5 tweets
#corsirosenthalbox TechTalk: Filter life and efficiency. Study of residential furnace filters in Toronto homes by Li & Siegel. Efficiency of MERV 8 improved, while MERV 11E, 14E (electret) dropped. @CappaSnappa @joeyfox85 @JimRosenthal4 @JbcLiftec DOI:… Figure 3 from: Tianyuan Li & Jeffrey Siegel (2020) Laborator
@CappaSnappa @joeyfox85 @JimRosenthal4 @JbcLiftec Li & Siegel [@Amy_Tianyuan_Li & @IAQinGWN] also reported on the size resolved performance of the same filters in another study. Note the minimum occurring at 0.3 μm (300 nm) and is better on smaller sizes. DOI:… Figure 2 from Li, T, Siegel, JA. In situ efficiency of filte
@CappaSnappa @joeyfox85 @JimRosenthal4 @JbcLiftec @Amy_Tianyuan_Li @IAQinGWN Of great benefit to #CorsiRosenthalBox is the very low face velocity compared to being in a duct. The efficiency is higher with slow airspeeds. This is more noticeable on small (12 nm) compared to larger (2330 nm) particles. Figure 3 from Li, T, Siegel, JA. In situ efficiency of fil
Read 7 tweets
1/ "serious waves of covid and because there could be other airborne pathogens which we want to protect against”

Yes, like influenza virus. Improved ventilation & filtration can dramatically reduce inhalation dose of virus-laden respiratory aerosols.…
2/ In a large fraction of classrooms it is possible to use a combination of increased outdoor air + a #CorsiRosenthalBox to achieve 10 to 12 ACH, approaching an isolation room in hospitals. And these are just 2 of several tools at our disposal.
3/ A #CorsiRosenthalBox can add up to an equivalent of 7 ACH to an averaged-sized K-12 classroom housing 25 to 30 students. At a cost of between $4 to $5/student/yr (a fancy coffee/yr) inclusive of build cost, replacement filter cost, and energy cost.
Read 5 tweets

2+ years into #COVID19 ,

which we have all suffered through collectively and hugely,

institutions are failing monstrously,

at protecting children,

whom you take more care with,

not less.


What’s changed?

Is it milder?


“Omicron as severe as other COVID variants -large U.S. study”……

Can kids <5 get a 💉?


Boosters 5-11?


Can you still get #LongCovidKids even if 💉?


=need more protections
So do we still need to prevent

transmission & infection

in PS & daycares

b/c more care with kids

not less

b/c #LongCovidKids



“Of all the myths associated with COVID-19, 1 of the earliest was that the virus is harmless for children”…
Read 30 tweets
Someone in your family has tested positive for covid. What can you do to prevent it from spreading to the rest of the household? Ventilation can help. A thread. 1/…
@CDCgov recommends isolating Covid patients for at least 5 days, preferably in a separate room with access to their own bathroom, as well as diligent mask-wearing for both patient and caregiver. 2/…
@CDCgov @CDCgov advice on home isolation for covid can be tough to follow. Not everyone has an extra bedroom to spare, let alone a free bathroom. Young children should not be cooped up alone for 5 days, and the youngest can’t tolerate masks. 3/…
Read 18 tweets
1/ Had a few folks ask where I’ve been in twitter discussions of COVID-19. Still here & doing what I can to promote & act on lowering inhalation dose of virus-laden aerosol particles. Continuing discussions w/ reporters & policymakers (when asked), but largely in the shadows.
2/ Been keeping up w/ twitter banter when I have breaks, some of which has been great & some enormously frustrating. My position as dean of @UCDavisCOE is demanding but exciting, and has been job 1 for the past 7 months. Hopeful to engage a bit more once the spring term ends.
3/ My passion for promoting the importance of lowering inhalation dose of virus-laden respiratory aerosol particles has not waned since the early days of the pandemic. If you've followed me for awhile you will be familiar with my early tweets.
Read 16 tweets
#WHCD2022. The infected thread.

Don't forget we are looking at 700 to 1400 possible infections. We may not hear all of them.

The very first one? Someone sitting right next to "Kete". Video of Kete at the table?

But of course. Image
You can't see Jonathan, but he's there.
Read 32 tweets
Your guide to stopping COVID in your home - short version

Here's a quick rundown of what to do. If you have questions or want more details, see this thread 👇

First, #COVIDisAirborne , it spreads like smoke. The more you breathe in, the greater chance you'll get infected.

What to do:
1. Vaccines - stay up to date
2. Rapid tests (RAT)
- if you are symptomatic (even negative RAT), assume you have COVID
- use RAT to confirm you are +
- once symptoms resolve, use test-to-exit:
- best 2 neg. RAT on 2 days
- at least 1 neg. RAT if you can't

3. Masks - wear respirators as much as possible (N95, KN95, KF94 or equivalent). If you can't get one, use a surgical mask with knot & tuck, but it's an inferior option.

4. Clean the air: (always do this, but if there's COVID, go all out)
- go outside
-open windows...

Read 6 tweets
#OnPoli #OntEd

Where is the analogous leadership?

There is an election coming

Stop catering to #COVID19 flat-earthers

🛑 #CovidTroglodyte response

Show me you understand science

Lead like @SoniaFurstenau…

Same in ON

We are all 1 mass re/infection away

“…the province is not doing much to educate the public about #LongCovid. She cited a recent study showing that #LongCovid can affect 1 in 4 children”

PHO = approx 50% = #LongCovid…

@SoniaFurstenau 👏

#OnPoli #OntEd

Match & lead

🛑 #CovidTroglodyte response

Election coming

“W/ HIV/AIDS…govts educated people about how the virus was being transmitted. They were told that unprotected sex & shared needles contributed to the spread.”


Read 18 tweets
Why isn’t there a #maskmandate in ON PS & daycares?


It’s a no-brainer

“ON will be extending #maskmandate in select higher-risk indoor settings for at least another month”…

More care with kids, not less

Ford 24/7 416-325-1941

#6ThWave ImageImage
The following have #maskmandate

Why isn’t there a #maskmandate in ON PS & daycares?

It’s a no-brainer

More care with kids, not less.

Ford 24/7 416-325-1941

#maskmandate NOW

#6ThWave ImageImage
Universities have them.

Why isn’t there a #maskmandate in ON PS & daycares?

It’s a no-brainer

More care with kids, not less.

Ford 24/7 416-325-1941

#maskmandate NOW

#6ThWave ImageImage
Read 20 tweets
Clean Air - the UK thread.

You are surrounded by CoVid and are desperate to keep LongCoVid at bay.

You've come to the right place.

It starts with P3/P100 elastomeric respirators, available at your local Screwfix (H/T @PlasticFull ).…
You will be a little more muffled than in an P2. If you are a teacher, many teachers in America wear a UHF microphone and speaker with it.

This is the one I use:…
Have a child? There is a US made child elastomeric respirator that can be shipped.

Best way of ordering?

Read 13 tweets
As box fans return to store shelves in advance of cooling season, will @Lasko_Products bring an optimized and safety-approved #corsirosenthalbox fan and filter frame kit to market? Even Lasko's AirFlex model could be greatly improved.
@Lasko_Products @Lasko_Products note the large purchases of your box fans to make air filter products suitable for the large volume of classrooms. Many jurisdictions refuse #corsirosenthalbox due to lack of safety certification despite EPA & UL blessing. You can help!…
@Lasko_Products @Lasko_Products, team up with @3M and work together! 3M has already tested their filters with your fan in lab tests of #corsirosenthalbox.
Read 3 tweets
Dear ON

You are forcibly being re/infected without informed consent w/ a

highly transmissible airborne





that can mass re/infect, kill, & disable

due to coercive blocking

of PH precautions…

Think about that
If coercion = preventing PH protections

that follow the science

of transmission & prevention

on record

acknowledged federally

during a global pandemic

that can disable 1 in 3 adults
or 1 in 4 kids,

can we still say that we are living in a functioning democracy?

We cannot flat earth ourselves out of a pandemic

It puts us in the viral dark ages

Flat-earth equivalent mythology is dictating PH policy

keeping us in the viral Dark Ages

Not science

Read 24 tweets
1/ 15 minute Rule?

Remember that what matters is the inhalation dose (D) - which is equal to C x B x t x f
C = concentration of SARS-CoV-2 virions in breathing zone air (inside of mask if mask worn) (#/L) embedded in respiratory aerosol particles.
B = .....

B = Respiratory minute volume (L/min) (aerobic exercise gives a much larger B than you have reading this at your computer --- perhaps 5 to 10 x)
t = time in indoor environment shared by an infected individual (min)
f = ....

f = fraction of virions that deposit in respiratory system (dependent on aerosol particle size conveying virions).

The 15-minute rule is a GROSS generalization that does not account for variations in C and B across different indoor spaces.
Read 11 tweets
This is what needs to happen…the virus is in the air. This is what people should see when they walk in any public space instead of jugs of hand sanitizer. Thanks @Amal4Solutions. @WHOSTP this will raise awareness and protect @POTUS and others. We need clean indoor air ASAP.
Read 8 tweets
The next time someone denies the use of a portable air cleaner in a classroom on a (false) basis that it might spread infection by moving air, or interfere with the HVAC system, show them this paper. @amandalhu @sameo416 (HT @Poppendieck).… /1
When determining the amount of outdoor air provided to a space, ASHRAE Standard 62.1's Zone Air Distribution Effectiveness factors to account for the inefficiency of air delivery and mixing to provide outdoor air to the breathing zone. /2
For example, in heating mode, with a ceiling level supply and return, the effectiveness is only 0.8. So we need to provide 25% more outdoor air. (image: User's manual for 62.1-2010) /3
Read 18 tweets
@AAOA - I'm a clean air advocate interested in keeping as many people CoVid-free as possible.

You are interested in keeping as many people in apartments as possible.

BA.2 which is currently ripping up apartment-heavy Hong Kong is going to lose you a lot of customers.

Here are some ways your customers' clients can protect themselves:

Would you be interested in working with some IAQ advocates to get some sort of one-pager or QR code in your customers' lobbies?

I hate to name drop, but....

@CorsIAQ and @JimRosenthal4 and myself all follow each other.

I run the Clean Air Crew FAQ for the #corsirosenthalbox.…

3M has endorsed this DIY method of cleaning the air:…
Read 4 tweets
Omicron. Hotel rooms.

TLDR? Could not pay me enough to stay in a hotel room. Stand alone motel cabin? Sure.
Hotel with corridors? No way.

Going to start with a quarantine hotel. They have CCTV and genomic confirmation, typically.

Will add more as time permits.

Mainland china. Designated quarantine hotel (DQH).

Bets variant detected. Afterwards, HEPAS added to the corridors to stop cross-room transmission.

All good, right?
You would be wrong.

#Covid is airborne, and it is incredibly transmissible.

4 or less breaths transmissible in hospitals with 6 ACH (excellent ventilation). That was at the original Wuhan stage of things.

Read 14 tweets
Shopping this morning. Most customers and employees were maskless. Shopping with Dentec ComfortAir respirator
Shopping for hummus in a respirator certainly triggered a lot of people.

While you're here, check out my blog page on COVID-19 resources.…
Want to get a @DentecSafety respirator like mine? Here you go:
Read 5 tweets
1/ El Gobierno de EEUU (La Casa Blanca, @WHOSTP45) por fin admite claramente que la COVID-19 se transmite sobretodo por aerosoles, por el aire ("airborne" = transmision aerea)

#COVIDisAirborne #SonLosAerosoles…
2/ "La forma más común de transmisión de COVID-19 es por pequeñas partículas que flotan en al aire [=aerosoles] minutos o horas después de que una persona infectada las haya exhalado"

"Hay varias estrategias para evitar respirarlas [..] y es importante limpiar el aire interior" Image
3/ La Administración Biden-Harris ha identificado la calidad del aire interior como una herramienta importante para luchas contra la transmisión de enfermedades de transmisión aérea en el Plan Nacional de COVID-19 (" Image
Read 13 tweets
1/ Important study of over 10,000 classrooms.

Upshot = lowering concentration of virus-laden respiratory aerosol particles in classroom air lowers inhalation dose of these particles and significantly reduces infection. Always been about this, folks.…
2/ Increasing ACH from lower than 2.4 to 2.4/hr - infections reduced by 40%. To 4 ACH lowered by 66.8%, to 6 ACH lower by 82.5%. With an appropriately-sized portable HEPA system or a #CorsiRosenthalBox we cannot achieve 10 ACH.
3/ "If the most efficient systems were installed "we could pass from 250 cases per 100,000 students (the alert level set by the education ministry) to a rate of 50 per 100,000."

Yep, its about lowering inhalation dose to virus-laden respiratory aerosol particles.
Read 9 tweets
1/ A context slide from my CITRIS webinar on 3/16/22.

We know it is possible to achieve a CADR > 800 cfm for a Corsi-Rosenthal box. So, let's compare its impact in a realistic dorm room & classroom relative to air changes per hour in, say, a hospital infection isolation room.
2/ In a standard 2-person dorm room (where masks are unlikely to be worn when two people are sleeping 10 ft away from one another for 8 hours!) the CR box yields an aerosol particle reduction equivalent to 24 air changes per hour (ACH).
3/ Without any other ventilation, this is 2 x a hospital isolation room! Measurements of natural ventilation in my home garage with the large garage door wide open have been in the range of 15 to low 20s for ACH depending on outdoor wind conditions.
Read 12 tweets

Related hashtags

Did Thread Reader help you today?

Support us! We are indie developers!

This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3.00/month or $30.00/year) and get exclusive features!

Become Premium

Too expensive? Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal Become our Patreon

Thank you for your support!