Thread by @MarcelHarmon1

These are the type of actions our pharmacies, hair salons, retail stores, offices, universities, k-12 schools, individual residences, etc., need to be taking, particularly w/... 1/

@KDHE @LDCHEALTH @lawrenceks @douglascountyks @UnivOfKansas @usd497 @LawrenceChamber #ksleg #ksed

https://twitter.com/CO2Guerrillas/status/1346347767669485568

a more transmissible strain spreading in the U.S. & months left before vaccination levels are where needed to be.

CO2 levels can be used to estimate ventilation levels, though it's important to account for factors like the number of people present, the size of,... 2/

the space, & the use of portable air cleaners. Pages 23-24 of this document from @HarvardChanSPH & @j_g_allen provide a means for estimating ventilation rates based on measured CO2 levels. 3/

schools.forhealth.org/ventilation-gu…

Here's a review shared by @linseymarr of specific CO2 sensors that can be purchased. I like the Aranet4, though there are other good ones that are easy for anyone to use. Looks like @CorsIAQ will also be providing a guide for doing the calcs soon. 4/

https://twitter.com/linseymarr/status/1344114560857468930?s=20

Other means to estimate existing ventilation rates are also provided in the guide I linked to in the 3rd tweet. And part of addressing ventilation is estimating what you're actually getting (either mechanically or naturally).

As poorly as awareness of the need to address... 5/

ventilation/filtration has been promoted by public health officials overall, the need to actually verify it has been even less discussed. Besides reviewing the previously referenced guide, you can also engage a consulting engineer, commissioning agent, or TAB contractor to... 6/

verify/estimate what you have.

Guides for improving ventilation/filtration certainly include @CDCgov's updated guidance on this: cdc.gov/coronavirus/20….

But also reference: schools.forhealth.org/risk-reduction…,
docs.google.com/document/u/0/d…,
ashrae.org/technical-reso… (@ashraenews),... 7/

fitwel.org/covid-19/ (@Fitwel),
reset.build/resources/COVID (RESET),
wellcertified.com/powerofplace/ (@WELLcertified).

For residences, take a look at @ShellyMBoulder's blog post: shellym80304.com/2020/11/02/mos…. 8/

However, avoid the use of electronic air cleaning technology like bipolar ionization or exposing occupants to Far UV-C:

https://twitter.com/MarcelHarmon1/status/1333139509354098690?s=20

https://twitter.com/MarcelHarmon1/status/1303773980545998848?s=20

https://twitter.com/MarcelHarmon1/status/1317101981664759810?s=20

.

Upper room UVGI systems can be effective, but you'll need to consult w/ experts. 9/

Besides those already mentioned, additional twitter accounts to follow relative to aerosols and ventilation/filtration include (I know I'm leaving some out):
@CathNoakes
@kprather88
@jljcolorado
@JimRosenthal4
@healthyheating
@Poppendieck
@HuffmanLabDU
@DavidElfstrom 10/

@DrEricDing
@covidisairborne
W/ some great reporting/writing by @apoorva_nyc & @zeynep.

In addition, building owners, municipal officials, public health officials, etc., could be using calculators like @BranchPattern's FIRE module (branchpattern.com/research/facil…) to estimate... 11/

probabilities of infection given specific conditions of ventilation/filtration, mask wearing, etc.

These estimates can be used to help establish varying combos of max no. of occupants, max exposure time, limits on activities, etc., for diff. spaces:

https://twitter.com/MarcelHarmon1/status/1346270198337314816?s=20

. 12/

This could help provide a better indication of the actual risks under different conditions, & therefore how to address & fund different mitigation strategies, from facility upgrades to de-densification to closures. Posted ratings could also increase community confidence,.... 13/

something that will be even more important over the next several months of winter/cold, working towards greater vaccination levels, w/ a more transmissible strain spreading.

We're currently multiplying the results of our FIRE module by 1.5 to get an estimate for the... 14/

probability of infection from this new strain, based on some of the recent studies looking at it. Though we'll be updating the module as additional research is conducted.

https://twitter.com/jcbarret/status/1344607063658405888?s=20

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Improving ventilation/filtration isn't just about addressing the threat of... 15/

COVID. We also know it improves productivity & health overall (e.g., linkedin.com/pulse/evolutio…). A more mindful, systematic approach to addressing ventilation/filtration now will help us get a jump on creating healthier environments in our post-pandemic world. 16/