Paul H's quest for covid-slowing things. Occasionally inventive

Culled chickens (without a gov bailout) mean that poultry farmers are excited about UVC: x.com/Welnesschick...
"My friend is an aerosol engineer that’s tests efficacy of far-UVC lighting. He said he’s been crazy busy with farmers. I hope more farmers adopt this tech to save their livelihoods."

* I know I am - monitormyhealth.org.uk/covid19-anti...

I'm up for an MRI at a private healthcare company called Spire (Murrayfield, Edinburgh) that has seven air changes an hour in the room the MRI is housed in - yay. I'm a novid so far* an trying to keep it that way.

Fungii: Aspergillus spp, Candida spp. (yeasts), Cryptococcus neoformans, Histoplasma, Coccidioides, Blastomyces

Bacteria: TB, Legionella. 2x Strep, Staph (including MRSA), Neisseria meningitidis, Haemophilus influenzae, Corynebacterium diphtheriae, Bordetella pertussis, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Bacillus anthracis spores, Clostridium difficile spores.

Viruses: SARS-CoV-2 (COVID-19), SARS-CoV-1, MERS-CoV, Influenza A & B, RSV, some Adenoviruses, Rhinoviruses, Enteroviruses, Measles, Mumps, Rubella, Varicella-zoster, Human metapneumovirus, Parainfluenza viruses, Norovirus, Rotavirus, Herpesviruses (HSV, EBV, CMV)

chatgpt.com/share/68de86... Context: Upper room UVC in a medical setting. Question: what is the full list of airborne viruses and bacteria would it be sanitized were the air currents to carry them to the top of the room?

Also. their doctor's liability insurers would tell them not to say that

Street sign saying "Elections ahead" with a Scottish flag above the text. Covid Action Scotland Logo. Three speech bubbles: "Access to Covid vaccines?", "Clean Indoor Air?", "Keeping patients and staff in healthcare safe?"

Public meeting, Sat, 19th July: 🏴󠁧󠁢󠁳󠁣󠁴󠁿Elections ahead: Addressing the Covid crisis - What do we need to see in Scottish parties’ manifestos for the 2026 elections to finally address the Covid crisis? Pls register on Zoom now: covidactionscotland.org/2025/07/04/e... ...(2)

Next one I make will be more box-like. I think the 45° filters will stay - how else will you see the chewing gum decorations?

Every school would need four per classroom to create the vortex of moving air. Potentially virus laden air up to the ceiling, across to these units, through the filters cleaned, then down the walls to and a little while later into vulnerable lungs

Many things make this to hard as a solo woodworking project. #IKEA could mass produce these as they have the ply knowhow. #Nukit could do folded-steel construction (still flatpack delivery)

Dirty filters removed (eww) - peering inside

As you'd see it if you were standing in the room. It's above your head per the ADA.

Bottom. These fans would blow down the wall it was screwed to

Side view

Back of unit that'd go against the wall (with space feet)

I made a CR box to place on a classroom wall as
@DtaGuy
has been pioneering. I'm not sure whether my build suits wood or whether injection molded plastic would be better. These pics on the carpet, if that wasn't obvious.

Gotta love Reddit, but the amount of stupid questions being asked by people that may have been smarter previously is shocking. I'd want mods to just delete the posts and maybe direct would-be posters to better techniques for answering their need rather that posting a stupid question to a popular sub

An attempt to coerce GPT into some renditions, two of many here. it can't quite depict the single room-sized toroid

Image shows plot of natural log of PM2.5 concentration vs time in minutes. The periods of exponential decay are chosen after the data is taken and Excel’s Linest function is used to find the slope. With the purifier off, there is 19.9 CFM of CADR due to wall deposition only. With the purifier on, there is 442.6 CFM of combined CADR. The difference, due to the purifier alone, is 422.7 CFM. The cool thing about CADR testing is if you get straight lines on a log-linear plot, you know your particle counter is linear, your mixing fan is adequate, and your chamber isn’t too leaky! The the part of the combined decay I fitted with Linest went from 673 µg/m3 down to 5.7 µg/m3, over 2 orders of magnitude very straight.

The SPS30 particle meter captures data for multiple size/mass ranges. This table shows CADR for three particle bin sizes as well as PM1, PM2.5, and PM10, at eight voltages. For V=9-12, values shown are mean and standard deviation (SD) for three runs. SDs are <3.7% at 12V and <2.3% at 9V.

This is a bar chart of the data in the table, showing how similar the smallest particle size (0.3-1.0 micron) CADR is to the largest. For these filters, 3M-measured efficiency at high face velocities is 95% for the large bin and 62% for the small one. But at these very low face velocities, efficiency goes way up, and since the small bin here is almost as good as the large bin, they are both probably nearly 100%, at least in the high 90%s.

I feel pretty good about measurements. I tested CADR in a 412.8 cubic foot bathroom, filled with nebulized NaCl solution, and mixed with a small fan. I used a Sensirion SPS30 Particle Counter, controlled by an ESP32 μcontroller, streaming into μSoft Excel. See ALT 4 more stuff.

Image shows a SketchUp view of the concept model. It uses four 24x24x1” 3M Filtrete 1900 MERV13 filters in an M configuration, above eight down-blowing 140mm Arctic P14PWM fans. (Shows simplified fan bodies, but not blades ‘cause that was easier to model.)

Finally! I built & tested an open-source concept model air purifier that should be good for schools. Lots of air (CADR > 420 CFM), quiet (<45 dBA), uses <9 W, and ‘cause it’s wall-mounted & down-blowing, it moves air in the right direction & takes up no floor space. Always check my ALTs🧵⬇️

I suspect part of the objection in schools is that they would ordinarily take up floor space, and be a kick hazard. Or fiddle-with-it hazard.

Looking forward to the video, Gary. Did you order any PIR switches yet? Like.. www.aliexpress.com/item/1005007...?

Wall-mounted IKEA components CR-box One IKEA SAMLA tub with sections cut out Two STARKVIND filters One three-gang PC fan assembly The IKEA tub is Polypropylene. That splits if...

Wee video if the wall-mounted CR-box I made from an IKEA storage box, two IKEA filters and a 3-gang PC fan assembly - fu-cv.blogspot.com/2025/05/wall.... Questions?

Antifragile (book) - Wikipedia

#AntiFragile (en.wikipedia.org/wiki/Antifra... talked talked about "some systems being strengthened by encounters with disorder". It needs a new chapter to list the reality that immune systems are not like this.

You're allowed to tweet "My excellent GP <full name, practice> said today ... QUOTE HERE".

Just say it matter-of-factly, and wait for them or their practice to do back flips to walk it back quickly.

Your immune system isn't a Tamagotchi that dies if you don't play with it.

"Immunity debt" is a marketing term to make you blame yourself instead of bad policy.

Getting sick constantly isn't normal — it’s a public health failure.

Barry Hunt---------------------I AM AIRBORNE AWARE on X: "@MirthDAL Today in 🇨🇦 you could use PMRA registered Upper Air GUV in classrooms & AutoUV in bathrooms. When companies get thru the PMRA registration process, you could use UV222 for either application. https://t.co/FEYBknCa1a" / X @MirthDAL Today in 🇨🇦 you could use PMRA registered Upper Air GUV in classrooms & AutoUV in bathrooms. When companies get thru the PMRA registration process, you could use UV222 for either application. https://t.co/FEYBknCa1a

A neat product to 10x the toroid filters idea x.com/BarryHunt008... @barryhunt008.bsky.social

Upper-room UV in smoke alarms - mains wired ones obviously Like this one:  Pic from https://en.wikipedia.org/wiki/Smoke_detector It'd come out close to 360 degrees at ceiling level. The smoke alarm w...

How many countries have mains wired smoke detectors? fu-cv.blogspot.com/2025/04/uppe...

It needs a expert human touch. "Handwashing" isn't a hazard, it's a FIX for hand-borne contaminants and pathogens. Smoking got an exemption as long as waiver-esque warnings were put on the packet and a minimum age for smoking tobacco was applied en.wikipedia.org/wiki/Tobacco...