@robwiss

I guess I make air cleaners now. Visit https://xitter.cf/t.co/JlbWu7b3Dv for prebuilt pc-fan corsi-rosenthal boxes and kits. @robwiss https://xitter.cf/t.co/t0Y3O9CXIe and threads

Joined December 2008
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A new pinned tweet -- all filter testing I've published to date. First, the test chamber write-up. xitter.cf/robwiss/status/1594196…
Rob Wissmann@robwiss20 Nov 2022
I've written up a more accessible version of the technique I use to perform at-home CADR tests in a test chamber. My current setup is a bit more advanced, it is automated and runs from a raspberry pi. Otherwise, it's the same. #AirFilterDev thewiss.blogspot.com/2022/11…
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LET'S AIR@nousaerons22 Aug 2024
Effective for its size (150 m3/h - 90 CFM), Quiet (< 40 db), Cheap (< 60 €), Easy (cardboard, adhesive tape, pencil, ruler, square, compass, scissors, screwdriver), that's our DIY air purifier. We'll release a first tutorial soon. Some details have to be fixed. 1/2
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Full PMC COVID-19 Dashboard for August 19, 2024 Please share across other social media accounts and websites. No permission required. Thankful for your support. 💪😷 pmc19.com/data
Current Levels for Aug 19, 2024 % of the Population Infectious 2.6% (1 in 38) New Daily Infections 1,260,000 New Weekly Infections 8,820,000 Resulting Weekly Long COVID Cases 441,000 to 1,764,000 Monthly Forecast Average % of the Population Infectious 2.5% (1 in 39) Average New Daily Infections 1,212,000 New Infections During the Next Month 36,360,000 Resulting Monthly Long COVID Cases 1,818,000 to 7,272,000 Running Totals Infections Nationwide in 2024 172,150,000 Average Number of Infections Per Person All-Time, U.S. 3.30 There is more COVID-19 transmission today than during 89.6% of the pandemic. How Does Risk Increase with More Social Contacts? Number of People | Chances Anyone Is Infectious 1 2.6% 2 5.2% 3 7.7% 4 10.1% 5 12.5% 6 14.8% 7 17.1% 8 19.2% 9 21.4% 10 23.4% 15 33.0% 20 41.4% 25 48.7% 30 55.1% 35 60.7% 40 65.7% 50 73.7% 75 86.5% Estimated % Infectious National 2.6% (1 in 38) Northeast 1.8% (1 in 55) Midwest 1.9% (1 in 52) South 3.4% (1 in 29) West 4.2% (1 in 24)

ALT Current Levels for Aug 19, 2024 % of the Population Infectious 2.6% (1 in 38) New Daily Infections 1,260,000 New Weekly Infections 8,820,000 Resulting Weekly Long COVID Cases 441,000 to 1,764,000 Monthly Forecast Average % of the Population Infectious 2.5% (1 in 39) Average New Daily Infections 1,212,000 New Infections During the Next Month 36,360,000 Resulting Monthly Long COVID Cases 1,818,000 to 7,272,000 Running Totals Infections Nationwide in 2024 172,150,000 Average Number of Infections Per Person All-Time, U.S. 3.30 There is more COVID-19 transmission today than during 89.6% of the pandemic. How Does Risk Increase with More Social Contacts? Number of People | Chances Anyone Is Infectious 1 2.6% 2 5.2% 3 7.7% 4 10.1% 5 12.5% 6 14.8% 7 17.1% 8 19.2% 9 21.4% 10 23.4% 15 33.0% 20 41.4% 25 48.7% 30 55.1% 35 60.7% 40 65.7% 50 73.7% 75 86.5% Estimated % Infectious National 2.6% (1 in 38) Northeast 1.8% (1 in 55) Midwest 1.9% (1 in 52) South 3.4% (1 in 29) West 4.2% (1 in 24)

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#YallMasking? Yep, Kylie Jenner was spotted wearing a respirator all last week while in Rome
Picture of Kylie Jenner outside with a black respirator

ALT Picture of Kylie Jenner outside with a black respirator

Picture of Kylie Jenner outside with a black respirator

ALT Picture of Kylie Jenner outside with a black respirator

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🤔 well as long as they did it cautiously
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what?? how??
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washingtonpost.com/dc-md-va/…

Caught by surprise: How covid summer is affecting the D.C. region

An increase in covid cases in the D.C. region has upended summer plans yet again, catching residents by surprise and sending them scrambling for at-home tests.

washingtonpost.com
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It’s nice to see that there can be a recommendation for what to do alongside an acknowledgement that the guidance may not be followed instead of that awful “we have to meet people where they are” rhetoric
Alexander Tin@Alexander_Tin20 Jun 2024
To curb H5N1 threat, @CDCgov urged dairy workers to don masks and goggles But @CDCFlu's Tim Uyeki conceded this week: "may not necessarily be practical given the environmental conditions. So throughout the U.S., every day, it’s only getting warmer" tinalexander.github.io/notes…
A screenshot of text that reads in part: "Tim Uyeki, CDC [00:50:50] In terms of respiratory protection, the recommendation is an N95 respirator, not a surgical face mask. Definitely the recommendation is for eye protection. And, as I mentioned, we’ve had two cases of workers with conjunctivitis and so goggles or a face shield. But as Dr Maderas recommended, this may not necessarily be practical given the environmental conditions. So throughout the U.S., every day, it’s only getting warmer and more humid. And Dr Maderas mentioned even for healthcare personnel, the challenges of wearing goggles or face shield and fogging up and so forth. So, what we can say is what the recommendations are. We can post all of the PPE that are recommended. We can post the guidance from CDC and NIOSH in there. But we also realize the reality is that workers may not comply. And so I think that we all have to work closely together, including with farm workers and farm owners and the dairy industry to see what

ALT A screenshot of text that reads in part: "Tim Uyeki, CDC [00:50:50] In terms of respiratory protection, the recommendation is an N95 respirator, not a surgical face mask. Definitely the recommendation is for eye protection. And, as I mentioned, we’ve had two cases of workers with conjunctivitis and so goggles or a face shield. But as Dr Maderas recommended, this may not necessarily be practical given the environmental conditions. So throughout the U.S., every day, it’s only getting warmer and more humid. And Dr Maderas mentioned even for healthcare personnel, the challenges of wearing goggles or face shield and fogging up and so forth. So, what we can say is what the recommendations are. We can post all of the PPE that are recommended. We can post the guidance from CDC and NIOSH in there. But we also realize the reality is that workers may not comply. And so I think that we all have to work closely together, including with farm workers and farm owners and the dairy industry to see what

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Was able to confirm protection factor of 14.4 ±0.6 at 30 cm with 4Lite on Low when measured with an OPC. I tested after injecting 300 g/L salt aerosol to rule out that a low PM level might artificially inflate the PF. Still not sure why discrepancy with CPC exists. @ghhughes
Adam Wong
@Engineer_Wong18 Jun 2024
Today, I continued my examination of respiratory protection equipment. I observed significant discrepancies between the data from a fit testing device and a particle counter. For instance, when testing the AirFanta 4Lite at a distance of 0cm with the "L" speed setting, the particle counter indicated a protection rate of 50, while the TSI 8020 reported a fit factor of approximately 6.5. At a distance of 30cm with the same speed setting, the particle counter showed a protection rate of 14, and the TSI 8020 indicated a fit factor of about 4.3. @gerard, obtained similar readings. I acknowledge that particle counters and fit testing devices operate differently. Particle counters directly measure particles larger than 0.3 microns, whereas fit testing devices use isopropanol to pre-treat the particles. However, the crucial question everyone is asking is: which measurement is more reflective of real-world protection against pathogens like COVID-19? I can offer some insight on this matter. Last year, a certified laboratory, "Guangzhou Institute of Microbiology Group Co., Ltd, National Center of Quality Inspection and Testing on Air Purification Products," conducted a germ filtration test on the 4Lite model, following the GB/T 5365-2019 standard. The test assessed the density of microorganisms at the filter's entrance and exit. They used "Staphylococcus albus" bacteria and "H1N1" virus for the tests. The average filtration rate for Staphylococcus albus was 98.42%, corresponding to a protection factor of 63. For H1N1, the average filtration rate was 99.51%, equating to a protection factor of 204. From these results, it's evident that the actual protection factor against COVID-19 and other pathogens is significantly higher than what fit tests and particle counters suggest. Both N95 respirators and the 4Lite device provide much greater protection than fit test results might indicate.
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My leading hypothesis is that CPC is counting 0.3 um and below better than OPC and the PF is indeed lower when particles of those sizes are taken into account. Someone get an SMPS!
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For those interested: turned on mixing fan, ran neb 7s, mixed 2 minutes, mixing fan off, 5 60s samples, 4Lite on Low, 5 60s samples. 300 g/L salt solution Temtop PMD331 in Total Count (TC) mode Used count of 0.3um and up
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Ceiling fan🌸OBLITERATED CLOSE-CONTACT 🧑‍🤝‍🧑 RISK: In eLetter in Science, we suggested CEILING FANS might cut short-range risk (w/ ventilation for long-range). Singapore lab found just that (2023): mannequin underneath fan 5 ft from cough 🌬️ inhaled ~ 95% FEWER particles. (1/6)
Devabhaktuni "Sri" Srikrishna
@sri_srikrishna7 Jun 2024
Today, Science published my eLetter with @RanuDhillon critiquing the "per person" ventilation target of: 14 lps / person🧍(21 cfm / person) proposed in Science article by Morawska et al. and replacing it with “per room” 🏡 + mixing targets. (1/22) science.org/doi/10.1126/scie…

Mandating indoor air quality for public buildings

If some countries lead by example, standards may increasingly become normalized

science.org
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Twitter was an incredible place to connect people globally to help get out the word on #COVIDIsAirborne. I met so many amazing people as a result. Great things happened based on these connections. My main goal has always been helping people understand how to....(1/10)
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I appreciate well-researched articles like the one here on the current covid landscape and agree with the conclusions. The 3-5% chance of long covid and likelihood of brain damage with each infection are serious consequences incongruent with the current “do nothing” approach.
Dan Elton 🔍
@moreisdifferent1 Apr 2024
So I am a bit ashamed to discuss this, but, for those who don't know: The first time I got COVID-19 was during the Omicron wave. I was on a 10 day trip in the SF Bay Area in June 2022. I know exactly how I got COVID-19. The one time I took my N95 mask off during the trip was during a job interview, and that's where I got it. (I sat in a room for a while without a mask with someone who tested positive 2 days later and I became sick 3 days later). I had severe #LongCOVID for about a year. I had chest pain, severe insomnia, and tinnitus for a solid month. The first six months I was severely ill - I could not work at all and I could not walk more than a block or two. There's a lot more I could say about this - one of these days I'll finish writing a long post on Medium that goes through the whole story. I was under a lot of stress at the time and I think that contributed to me developing Long COVID (possibly through Epstein-Barr reactivation). Anyway, about 10 months after my first infection I got COVID-19 a second time at a conference where I didn't mask. It took me at least 6 weeks to recover. I took two rounds of Paxlovid. The 3rd time I got COVID-19 was about 4 weeks ago. It was also after a conference where I didn't mask. It took 4 weeks or so to recover and I had to take 2.5 rounds of Paxlovid. So now I mask at conferences. I learned the hard way. I hope others don't have to learn the way I did. COVID-19 is not going away. Also, I took a hard look at all the scientific literature recently on #LongCOVID risk and the risk of brain damage from COVID-19. If you care about your health, everything I've learned strongly supports strategic masking with a well-fitting N-95 or respirator in high risk environments: moreisdifferent.blog/p/all-o…
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Another way to look at it: Finding the xz backdoor was a low probability discovery. For it to happen, there would need to be a large amount of similar vulnerabilities. By the time you see an ant, there is already an infestation.
Eric S. Raymond
@esrtweet30 Mar 2024
Replying to @esrtweet
2/ Open source worked the way it's supposed to. Some hacker noticed something that made him curious, poked at it because hackers are like that, and because the code was open and availablwe for inpection, diagnosed the problem before any serious harm was done.
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What if we did those things again for a couple of years, made flu extinct entirely, then never had to get flu shots again? 🫠
Noha Aboelata, MD
@NohaAboelataMD8 Mar 2024
Pretty amazing. Apparently, "...precautions that helped people avoid Covid-19 – including masking, staying at home and better ventilation..." have caused the Yamagata strain to become extinct. VRBPAC voted unanimously to remove it from future flu vaccine. cnn.com/2024/03/05/health/fl…
The Covid-19 pandemic killed off one strain of the flu, and that will change the next vaccines By Brenda Goodman, CNN 4 minute read Updated 3:51 PM EST, Tue March 5, 2024 Experts who advise the FDA voted unanimously to change the formula for flu vaccines from four strains to three.

ALT The Covid-19 pandemic killed off one strain of the flu, and that will change the next vaccines By Brenda Goodman, CNN 4 minute read Updated 3:51 PM EST, Tue March 5, 2024 Experts who advise the FDA voted unanimously to change the formula for flu vaccines from four strains to three.

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We've got a new artist (old friend) and new artwork for our Brisk Box Assembly Guide. cleanairkits.com/products/Br… is our economy taped PC fan Corsi Rosenthal Box that, thanks to four filters, boasts super low noise and amazingly uses < 10Watts for 5-8 person ASHRAE241 clean air coverage.
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📣 The @ilga is back in session! Pls support IL HB3713 Clean Air for Healthy Equitable Schools. We already passed the House and are now hoping to be assigned to a Senate committee (deadline to pass out of committee is 3/15). Please like & repost! Let’s make some noise! 📣 #twill
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Rob Wissmann retweeted
Lisa Oshima@lisawhelan2 Mar 2024
So many kind invitations! I wonder if @ashishkjha @CDCDirector will accept any of them. 🧵⏬ xitter.cf/JenjySays/status/17639…
Jenn 💜@JenjySays2 Mar 2024
Dr. Jha you are welcome to join us for lunch in the school cafeteria as well. I measured CO2 on Monday, peaked at over 2,000 ppm. Kids coughing everywhere. School refuses HEPA filtration and doesn’t allow teachers to open windows. I recommend bringing a packed lunch though.
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This really is the crux of the issue. There is a moral imperative to not spread disease. It's an enormous burden on individuals to fulfill that moral imperative because society's incentives are massively aligned against it. That should change.
Jessica Ellis@baddestmamajama1 Mar 2024
Replying to @baddestmamajama
I try and try to fight down the impulse to yell directly at the people I care about on this, but I’ve gotta: your lax behavior has made me sick permanently and kills many people every week. If you want to be a good person, fucking mask up. There’s no other option.
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Wait, why don't they recommend those things? It seems like they should.
Ashish K. Jha
@ashishkjha1 Mar 2024
Replying to @ashishkjha
The question is not whether guidance will have benefits If we only focused on benefit Public health would recommend You never drive over 30 MPH Ever drink alcohol (no amount is safe!) Ever eat bacon (class 1 carcinogen!!) And so on But those would be bad recommendations
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