How Masks capture your Exhaled Covid19 virions
I wore Masks to protect semiconductor crystals from aerosol and droplets exhaled through my mouth and to protect others in case I was an Asymptomatic spreader. I don't expect them to protect me.
My history as a Proud Face Mask Wearer
I was once asked to pose for the Australian Department of Foreign Affairs and Trade for their publicity of R&D capabilities while I was working for Telecom Australia, now known as Telstra.
Normally I would have been wearing a Mask if growing heteroepitaxial semiconductors using the MOCVD apparatus shown.
You can see I had to stick my head in a laminar flow cabinet that swept any particles I emitted down through the perforated work surface.
Expert engineers designed my cleanroom lab which had a double entry where everyone entering had to wear suits, masks and eye protection. Our goal was to minimize particulate contamination of the semiconductor wafers so that the electronic properties would achieve the desired optoelectronic properties.
Prior to working there I had some detailed knowledge of particle behaviour and surface chemistry that helped me grasp the finer points of High Efficiency Particulate Air (HEPA) filtration.
How do Masks capture Exhaled Covid19 ?
I highly recommend this paper to anyone interested in how masks work to reduce exhalation of Covid19. Contains many useful references.1
I use this figure from it that defines the problem. It is vital to understand the size difference between Air molecules, Aerosol and Droplets and see where Covid19 virions fit in the scale.
Note that the Falling time is slower, the smaller the particle.
Using laser illumination it is possible to see the droplets exhaled during normal speech, all of which could carry virus and nearly all of which will be captured by a properly fitted face mask, floating around in the air for minutes.
I initiated a discussion on Gettr of the demonstrated effectiveness of masks in capturing exhaled Covid19 virions because I am concerned about the risks associated with repeated mid-turbinate swab collection.
A study from South Korea2 neatly demonstrated that exhaled Covid19 is easily captured using KF94 or N95 masks, and the inner electrostatic filter was selected for virus quantification. As expected, captured virus load increases with time of wearing and the researchers were delighted to find they obtained better results than analysis of worker plasma. So they suggest nasal swabs be replaced by mask collection. They foresee miniaturization technology that will integrate PCR assays on face masks!
Physics and Chemistry of Mask Particle Capture
The key concepts in HEPA filtration [TMS ref] revolve around the following processes in Air, which is a Fluid:
1] Diffusion, including Brownian Motion of the smallest
2] Interception during diffusion, largely due to electrostatic attachment
3] Straining of the large droplets
4] Inertial Impaction, or direct contact.
How Small are Covid19 Virions ?
A lovely study of an Asymptomatic Superspreader, who exhaled infectious Covid19 for 70 days, includes high quality electron microscope images of the virions caught in swabs.3
The Covid19 virions are typically about 125 nanometres (or nanometers in American) in diameter, including the Spike Protein extensions.
Standard Tests to measure Mask Efficiency
Simple face masks made from fabric compared with N95 respirator shows they are very effective at removing tiny particles from exhaled breath using standard test methods employing salt (NaCl).4
The real world comparison between a NPV respirator and various fabrics, including when a large hole is punched into the samples, for capture of a large range of particle sizes.
The experimental setup is shown
Room Air Filters as supplied to Schools
So, how do face masks and HEPA room air filters, as distinct from masks, go in terms of the Size of the airborne particles being captured? For particles the size of a Covid19 virion at 125 nanometres diameter including Spike Protein protrusions, the measured efficiency is typically 99.995%. Of course the chances of a single virion leaping off your tongue all by itself are very close to zero, so particles captured will always be bigger. So let's be happy to say better than 99.9%.
See the nice video5 at this page.
Pointless wearing Masks with Exhaust Valves
Nice set of 2020 videos from the US NIST looking at exhalation through masks.6
“I don’t wear a mask to protect myself. I wear it to protect my neighbor, because I might be asymptomatic and spread the virus without even knowing it.” — Matthew Staymates, NIST research engineer
The Importance of Electrostatics in Virus Capture
Face masks work by surface chemistry which determines electrostatic charge. Here is a clever approach that captures and traps viruses from the air using a flat charged plate, with nice images of trapped individual virions of Rotavirus and Influenza virus.
Always assume you are Infected
Lovely example of Israeli doctor, triple jabbed with Pfizer, who infected one of his friends while he was Asymptomatic and viral load was growing in him.7
Study of Asymptomatic Covid19 spreading in vulnerable populations in Italy.8
And another Asymptomatic study from Germany.9
To add to the confusion we have Paucisymptomatic Covid19 spreaders.10
A study under controlled conditions, from March 2020, in which all positive testing members were prevented from flying, and which demonstrated the effectiveness of everyone wearing masks, they found "the most plausible explanation for the Transmission of SARS-CoV-2 to a passenger on the aircraft is that she became Infected by an Asymptomatic but Infected passenger while using an onboard toilet." "N95 respirators were provided, and passengers were kept 2 m apart for physical distancing during preboarding. Most passengers wore the N95 respirators except at mealtimes and when using the toilet during the flight."11
Psychology of Mask Effectiveness Denial
I chat with a friend who is qualified in Psychology every day, and I studied the subject as part of my business administration diploma.
Real world experience in the campaign against Fluoridation Industrial Waste Disposal has taught me the great difficulty of overcoming emotional responses when people are confronted with beliefs that have usually been inculcated from their early years.
Most people are brought up to trust men in white coats who tell them, for example, that Fluoride, from toothpaste or ingested in poisoned water, will prevent tooth decay.
Most people, including myself, trusted vaccination until they saw the dreadful and sometimes fatal side effects in their family or friends.
Given this high level of trust, some “leaders” of the campaign against Mandatory Jabbing have been successful in mobilizing support, by using the dislike of Mask wearing, instead of the more difficult task of directly attacking vaccination.
By lumping the 2 separate issues together, under the heading of Control, they expanded the movement.
The irony is that once mobilized, citizens following the banner have difficulty distinguishing fact from fiction.
As an example, I recently saw Stew Peters conduct an interview where he claimed that there is Graphene in jabs (where there is absolutely no evidence), then pulled out a pencil with Graphite in it, then said that is Lead, then ended the show saying they want to inject Lead into Children!
Imaginary Graphene (Carbon) > Graphite (Carbon) > Lead (the metal Pb) transmutation fantasy that has been seen by over 4 million viewers!
Another aspect is latent Guilt. Those who rejected all masks, then visited an elderly person who subsequently died, will have sleepless nights if they accept the possibility that they carried infection to their loved one.
An important psychological barrier is identifying mask wearing as a sign that the wearer might actually be infected, with the idea that anyone actually infected should be ashamed. Hence the label of the protective Mask as “Shame Muzzle”.
“Shame Muzzle” Alternative
Some common objections to wearing a mask are:
1] Inhalation of fabric particles from the mask
2] Reduced exhalation of Carbon Dioxide
3] Growth of bacteria in captured spittle droplets
A neat solution that filters the Inhaled air, but does little to stop Exhaled virus was developed before the Covid19 pandemic.
Experts in HEPA filtration like Dyson have been working on filtering inhaled air using a novel approach prepandemic. The company's filters are excellent for filtering particles less than the size of a single virus. They provide test data for efficiency for particles of various sizes.
Read more about Asymptomatic transmission of this deadly virus.12
Update
A useful Thread on how masks work that was started in December 2022, while I was suspended from Twitter.13
Nice article showing capture of Monkeypox Virus by patient masks.14
https://www.researchgate.net/publication/343263629_A_Complete_Debunking_of_Denis_Rancourt's_Mask_Don't_Work
Kim H-S et al. Collection and detection of SARS-CoV-2 in exhaled breath using face mask https://pubmed.ncbi.nlm.nih.gov/35980889/
https://www.cell.com/cell/fulltext/S0092-8674(20)31456-2
https://pubs.acs.org/doi/10.1021/acsnano.0c03252
https://www.tms-lab.com/can-hepa-air-purifier-capture-the-covid-19-coronavirus/
https://www.nist.gov/news-events/news/2020/11/new-airflow-videos-show-why-masks-exhalation-valves-do-not-slow-spread
https://www.theguardian.com/world/2021/dec/01/israeli-doctor-believes-he-caught-omicron-variant-of-covid-in-london
https://pubmed.ncbi.nlm.nih.gov/33321208/
https://www.nejm.org/doi/full/10.1056/NEJMc2001468
https://www.forbes.com/sites/coronavirusfrontlines/2020/05/16/the-term-asymptomatic-is-more-complicated-than-it-seems-when-it-comes-to-coronavirus-infections/?sh=7438726d61d9
https://wwwnc.cdc.gov/eid/article/26/11/20-3353_article
https://pingthread.com/thread/1602994049815908353
Hernaez B, et al. 2022. Monitoring monkeypox virus in saliva and air samples in Spain: a cross-sectional study.