Science and critical thinking fan. Not actually a cat. He/him.
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Jun 30 • 6 tweets • 3 min read
Finally! Nice looking black tri-fold respirator masks that perform as well as 3M Auras, the Project 3 Trident FFP3s.
I tested the regular size and the regular size with extended strap length with a quick PortaCount test to see how well they fit and filter, and they scored higher than a 3M Aura 9205+.
I also checked out the strap tension to see how they differ from the 3M tri-fold masks. Turns out there is *a lot* more strap tension, even the "extended" straps version.
The straps are longer at rest than a 3M Aura, so it might seem like they would be looser, but the strap material is much thicker. And I found them to be a bit tighter than I'd like.
These black tri-folds are a collaboration between The Face Mask Store in the UK and Trident Safety in Australia to make nice looking black versions of Trident's existing masks. They are certified as FFP3 respirators, the EU's highest standard for filtering facepiece respirators, a standard that is more protective than the US N95 standard.
The Project 3 masks come in extra small, small, regular, regular extended straps and XXL. When in stock, The Face Mask Store offers a sample pack with 1 of each size.
I purchased these myself for review.
Test results in the video:
222nm UV light, "Far UV", is a wavelength of invisible light that can sanitize air while being safe around people.
One company tried to monopolize the use of this frequency of light to sanitize air, in the middle of the pandemic. That company is Sterilray (aka "HEO3").
Sterilray had a patent for the use of 222nm UV light with other frequencies to sanitize air, and they broadly interpreted that idea in their own favor, filing lawsuits against multiple companies during the pandemic.
In 2022 they sued competitor Far UV Technologies for making and selling a competing product.
Before suing they not only demanded licensing fees from Far UV Technologies, but also from everyone who had bought lights from them.
Yeah, that's a thing. A patent holder can demand licensing fees and also sue *end users*, not just manufacturers, for patent infringement. That includes not only hospitals and venues who bought competing Far UV lights, but also the general public who bought them to be safer from airborne infection.
The pandemic was ongoing, and Sterilray decided there was money to be made by killing the development and use of Far UV by anyone other than Sterilray and their customers or paid licensees.
The thing is, their patent claims were BS. They claimed a legal monopoly on things they had no right to.
After Sterilray started suing over their patent, 4 UV companies collaborated and financed a challenge to the 8,975,605 B2 patent.
In October of 2023, the Patent Trial and Appeal Board found *all* of the challenged patent claims to be unpatentable and invalidated them.
Thanks to that win over Sterilray's specious patent claims, individuals, companies, and open source projects can design, innovate, manufacture and sell Far UV products without facing financially ruinous licensing terms or lawsuits from Sterilray.
Because there is no "non profit" or "open source" exemption to US patents, if Sterilray had won the patent challenge I'd expect even open source projects like @TheOSLUVProject would be dead in the water. It seems unlikely Sterilray would allow open sourcing of their patent after paying all that money to sue competitors over it. And even if they did agree, patent grant issues can complicate or ruin open source projects.
The over broad patent claims of Sterilray were antithetical to the public interest, and to open source development.
The Patent Trial and Appeal Board ruling against Sterilray's claims is a victory for the public in general, and public health specifically
May 18 • 5 tweets • 4 min read
5 years into Covid some people are still arbitrarily trying to apply workplace respirator regulations to respirator use by the general public, even though they are different paradigms.
@kristinaEBP has experience running an industrial respiratory program, and pushes an absolutist occupational regulation approach to masking and mask fit testing in spite of the fact that the general public doesn't have affordable access to mask fit testing. Nonetheless, she calls community mask fit testing "criminal".
Stealthy Jess / @AdvancedTweaker does innovative mask testing and mask fit testing, including harm reduction testing by using a PortaCount to see how various masks are affected by things like getting them wet, or decorating them.
People are decorating masks anyways, so Stealthy Jess tests things people are **already doing** to see which may have more or less risk
It's institutional orthodoxy vs. innovation and harm reduction.
Getting people in to masks that fit them well is one of the best ways for them to be better protected from airborne hazards. In the US, only employees required to wear respirators at work get fit tested, at their employers expense.
The general public is left to fend for themselves, often told to forego respiratory protection entirely if they aren't fit tested, even though most fit testing companies won't fit test individuals, and the few that do may charge $75 - $150 *per mask* just to see if they fit.
So, volunteer community fit testers have stepped up to fill this void that should not exist. In the US, there is no training requirement or certification to perform OSHA compliant fit testing - so it would be defamation per se to claim that volunteer community fit testing in the US is "criminal".
To my mind, inflexibly applying workplace respiratory protection rules to the general public is harmful and counter productive.
The paradigm for mandatory workplace use is totally different than for voluntary use by the general public.
At work, if you don't get fit tested you don't get a respirator and you aren't allowed in the contaminated environment (this is part of the Hierarchy of Controls, where staying out of the contamination is the first, safest choice and masks are a last resort). In workplaces, those rules make sense to make workers safer.
But for the general public, we are already in the contaminated environment, so fit testing rules just prevent people from getting good protection for the situation they are already in.
More fit testing for the general public == more people getting better respiratory protection. And workplace fit testing rules and companies cannot and are not making that happen.
I see community fit testing as vital to helping the general public staying safer from respiratory hazards, including particulates from wildfires as well as airborne disease.
To find volunteer community fit test in your area you can check the Fit Testing for Everyone Discord server:
Most tri-fold masks I try don't pass a fit test on me because they leak at my nose bridge. The WellBefore 3D Pro KN95 is the first earloop tri-fold I've tested that fits me well enough to pass an N95 mode PortaCount fit test.
I compared the 3D Pro to a 3M aura using PortaCount Mask fit testing machines.
You can check the YouTube video for quick summary:
A number of things stand out to me about the 3D Pro. The first is the sturdy nose wire. A good, strong nose wire is a key to sealing a mask well at the nose bridge. 3M Auras and Drager 1950s have excellent nose wires that seal well, but almost every other tri-fold I've tried has a weak nose wire that is reminiscent of twist ties. The 3D Pro nose wire, combined with the comfortable large nose foam, works well on my high nose bridge to give me a good seal.
Another good feature of the 3D Pro is that the earloops are adjustable. Normally I don't get a good seal from earloops - headbands are typically more comfortable and better for the tension needed for a good face seal. However, the individually adjustable earloops let me get a good enough seal to pass a fit test. But keep in mind that you do need tension on the earloops. If you make them loose, you may reduce the seal of the mask.
Overall I'm pleasantly impressed with the 3D Pro. Although the filter media isn't as good as a 3M Aura it is good enough to meet the 95% filtration requirement for KN95s. And the seal is surprisingly good for an earlooop mask.
This testing is preliminary. It will take more testing to see how repeatable the results are, and how the mask holds up under wear.
Fit is individual. Your fit with this mask may be very different than mine. Check below to see how you can do a home fit test to make sure you are getting the best protection from your masks.
Apr 14 • 9 tweets • 5 min read
This is what we are losing when the government axed NIOSH and its National Personal Protective Technology Laboratory:
A 10 year plan "focused on novel hazards, PPE shortages, and advancing nationwide PPE expertise and capabilities"
NIOSH was making sure that the inadequate PPE issues from early in the pandemic didn't happen again.
• Develop, evaluate, and innovate PPE performance requirements & test methods by integrating advanced PPT & design guidance
• Develop & disseminate strategies & tactics to extend PPT supplies during emergencies, disasters, or PPT shortages
• Develop and disseminate guidance & best practices to inform PPT implementation & enhance user adherence
• Provide national leadership to inform the design & execution of NIOSH’s Respirator Approval Program (RAP) & other PPT conformity assessment schemes
•Expand U.S. capacity for PPT research and innovation
This is from an official presentation by Susan M. Moore, NPPTL Associate Director for Science
NIOSH was working outside the box, including using BARDA competitions to develop innovative respirators and ways to test how well masks seal and protect you.
Mar 13 • 6 tweets • 3 min read
Do clear face masks work?
I tested 4 clear panel face masks with a fit testing machine to see if they fit and filtered as well as a regular N95.
The results were mixed, but one mask stood out to me, the Optrel P.Air Clear.
Clear masks can help people who read lips understand you better and may help in situations where masks are restricted on the claim that they obscure your identity. But to be useful they still need to offer protection from airborne particulates. Not all do.
One that was recommended to me as being popular in the lip reading community did especially poorly, the Safe 'N' Clear "The Communicator" mask. It is a procedural (aka surgical) mask, a design that was not created as respiratory protection & does not seal well.
My "Fix the Mask" N99 Fit Factor for "The Communicator": 3
What I mean by " 'Fix the Mask' N99 Fit Factor: 3" is that I sealed the mask to my face as tightly as possible with an elastic Fix the Mask brand mask fitter (a best case scenario) and the air inside the mask was only 3 times cleaner of sub-micron particles. Without Fix the Mask the N95 FF was 2.
Dec 7, 2024 • 6 tweets • 2 min read
Do N95s and KN95s filter viruses?
Yes.
Here's an electron microscope image of salt particles on the fibes of a KN95 by @zhouliang_mask.
The image is of a NIOSH-type salt loading test of the melt blown filter media used in Zimi 9541.
The "big" crystals are about 1.5 microns. The smaller captured particles are as small viruses like Covid.
Covid virions are about .07 microns, are expelled into the air in larger respiratory droplets.
reddit.com/user/zhouliang…
If you are thinking, that's just salt, not viruses, not to worry. Scientists have tested N95s using real viruses using an international standard test called Viral Filtration Efficency (VFE). N95s filter viruses extremely well.
Can you make a cheap Amazon Plague Mask into an effective tight fitting PAPR mask?
Yes, yes you can. If you happen to already have a bunch of stuff everyone totally has lying around their home:
Honeywell 700 PAPR blower
Honeywell PA034L Y Adapter
Honeywell 5500 Series 1/2 Mask Respirator
youtube.com/shorts/QYuSbgE…
I've also done a 4 exercise OSHA fit test in this hacked Plague PAPR mask and passed - well, I got a great fit factor but the hacked mask isn't OSHA compliant, nor is fit testing a PAPR with the blower on, so some might say it didn't pass. 🤔
Sep 23, 2024 • 12 tweets • 4 min read
More from @NIOSH's Respiratory Protection Week presentation by Susan M. Moore, NPPTL Associate Director for Science:
Respirator fit solutions for people with beards.
The Singh Thattha technique can help, but it is not yet OSHA approved. NIOSH is studying this method.
Currently OSHA fit test regulations require smooth skin at the respirator seal, as shown in this graphic.
But some people have beards for cultural, religious and even health reasons that are incompatible with those regulations. Solutions are needed for equitable safety.
Sep 10, 2024 • 10 tweets • 3 min read
Thoughts about @NIOSH's Respiratory Protection Week presentation by Susan M. Moore, NPPTL Associate Director for Science:
The presentation showed current and future source control respirators, including a NIOSH exemplar model source control elastomeric mask for HCWs.
I was glad to see elastomeric source control respirators highlighted. Dr. Moore referenced industry creating source control elastomerics for the pandemic. But the 3M mask with the exhalation filter shown is a bit of a mixed bag.
ReadiMask is still selling old stock stick on N95mmasks from ~4 years ago, made before NIOSH approval with no warning about whether the adhesive may have degraded over time.
How old is the other mask stock they are selling? And has the adhesive degraded?
readimask.com/collections/re…
The Readimasks I have don't seem to be adhering as well as when I bought them. I managed to supplement the adhesive with Mastisol liquid adhesive supplied by @findmeabluebird, but I'd like Readimask to be more transparent about the age of their stock.
Are valved masks cooler? I tested 3 different 3M N95s to try to learn more about the effect of valves on heat in respirators.
Not much mathematical difference on average, under these specific conditions, with these 3 masks:
V-Flex +7.3°C
Valved Aura +7.3°C
No Valve Aura +7.5°C
I expect that results could vary dramatically under different conditions, including temperature, humidity, airflow rate, mask model and more. Even so, I was surprised that the valve didn't make a more substantial difference in average in-mask temperature.
Jun 17, 2024 • 5 tweets • 1 min read
Testing the AIRfanta Lite4 - the full length video.
I used several kinds of testing machines to characterize the amount and location of protection this portable laminar flow air purifier @Engineer_Wong sent me for review.
The video has a PortaCount test as well as the AeroTrak test - they measure different sized particles. I used a different particle range in the AeroTrak graph in the video than the one I posted on Twitter earlier, but they both illustrate the on vs. off axis protection levels.
Jun 14, 2024 • 7 tweets • 2 min read
Can a special laminar air purifier protect you where you have to go maskless, or let you take off your respirator where you normally would not?
@Engineer_Wong sent me an AIRfanta 4Lite to try out.
Tests showed the near field protection to be narrow, and less than mask level.
I used an optical particle counter to confirm my PortaCount measurements, and the results are similar.
This bubble chart shows how the count of particles even slightly off-line of the center axis of the air flow is higher.
(Unfiltered ambient count upper left.)
Oct 31, 2023 • 10 tweets • 4 min read
8 of the top 10 hits on Amazon for "respirator" are copies of the 3M 6200. Are they safe?
I tested one Amazon sent me for review, and the results are far worse than I expected: a 33% leak.
Don't trust generic respirators to protect your health.
The mask fit test results:
Generic 6200 Fit Factor: 3
Genuine 3M 6200 Fit Factor: 9612
The 3M performed 3204 times better than the copy.
Another 6200 copy tested better: FF 27. Still short of the needed min. of 100.
All copies tested significantly lower than genuine 3M.
Oct 24, 2023 • 10 tweets • 4 min read
Can a black KN95 over a 3M Aura, as seen worn by @ModelAyshaMirza, pass a fit test ?
Short answer: Yes, it can. It did on me.
Longer answer: Fit is very individual. You'll need your own fit test to know. Double masking often reduces fit a bit, but can also improve it. YMMV.
To test this double masking configuration, I first tested the 3M Aura 9205+ worn normally on my face by itself. I used a PortaCount in N99 mode.
Full OSHA N99 mode fit factor: 355
That essentially means the air inside the mask is 355 times cleaner, total inward leakage 0.3%.
Oct 23, 2023 • 8 tweets • 4 min read
Can tiny nostril filters protect you from Covid?
Lots of people would like unobtrusive respiratory protection, and nostril filters are an attractive option, or they *could be* if they work, and if you only breathe in through your nose.
🧵
I was given these by Amazon to review. They are from O2 Armor, who provide more filter data than most companies. But check their wording and compare it to their filtration efficiency graph..."up to" is doing a lot of heavy lifting.
Oct 10, 2023 • 5 tweets • 2 min read
Beware of Amazon Big Prime Deals on Respirators.
The top discounted respirators are part for part copies of 3M half masks. They have the appearance of a NOSH approved 3M respirator, but without the performance or quality control.
There are some genuine NIOSH approved respirators on sale at Amazon, including some 3M, but you have to look carefully. The copies look identical and even have the same model numbers, but *usually* don't have the 3M or NIOSH logos.
Sep 14, 2023 • 8 tweets • 2 min read
CleanSpace PAPRs are perma-dead when the rechargeable battery dies.
There is service for dead or dying batteries out of warranty. So don't count on your unit lasting longer than the warranty period.
They are great tools, but have a limited lifespan.
The CleanSpace rechargeable batteries can die permanently even if you just are storing the PAPR, as a number of people found out when they bought discontinued CleanSpace2s from Fisher Scientific with dead batteries. Fortunately, those customers were made whole, eventually.
Aug 22, 2023 • 12 tweets • 5 min read
What can you do if you have to have dental treatment, but don't have access to a dental office that masks?
A stick on nose-only mask can help reduce your exposure to airborne hazards.
I tested a few nose-only hacks and compared them to masks worn normally. They did help.
1/🧵
The best performing hack was @findmeabluebird's way of using a stick on ReadiMask N95 as a nose-only mask. I tested it with an 8 exercise fit test and got a bit lower score than I did with a single exercise test a while ago, but it is still protective.