Other companies make similar testing machines, including Accutec, OHD, Sibata and OpenAeros.
08.03.2026 02:28
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Other companies make similar testing machines, including Accutec, OHD, Sibata and OpenAeros.
I have no financial interest in promoting PortaCounts. I use them, but have no affiliation with the manufacturer, TSI. They are just an all around better fit testing method. They are more accurate and not reliant on subjective impressions of taste.
PortaCount Fast Fit testing takes just 2 and 1/2 minutes (not including the time it takes to put on your mask and purge ambient air from it) and gives an exact numeric score. The score tells you if your mask currently protects you well or if you need to try a different model for better fit.
Sax either doesn't know what is in fit test solution, or doesn't care because he's fixated on casting it in the worst light he can invent without regard to the facts of fit testing.
If Dr. Sax is so against qualitative fit testing, he should advocate for PortaCount fit testing at his institution.
Qualitative fit testing uses a nebulized spray of either pure saccharine dissolved in distilled water or pure Bitrex dissolved in 5% saline solution. There is no fragrance. It is a taste test, not a smell test.
www.osha.gov/laws-regs/re...
...while turning your head side-to-side, and sniff some weird, sweet fragrance that seems inspired by a stick of bubble gum in a 1980s baseball card package."
He's ignorantly trying to vilify *qualitative* fit testing.
Responding to being informed it was time for his annual mask fit test, he wrote in the NEJM:
"Translation: Drop everything, report to some booth in the hallway, don your N95 mask of choice...
Dr. Sax either doesn't know that OSHA-approved quantitative PortaCount fit testing exists, or choses to pretend it doesn't so he can generically mischaracterize mask fit testing to try to falsely discredit it.
www.osha.gov/laws-regs/re...
There are two kinds of mask fit testing used in healthcare:
• Qualitative, which uses a nebulized spray you can taste if it gets in your mask.
• Quantitative, which uses a PortaCount fit testing machine to count how many ambient particles get inside your mask.
youtube.com/watch?v=2xyN...
Harvard doctor Paul Sax MD wrote an OpEd in the New England Journal of Medicine to get rid of annual mask fit testing without knowing how mask fit testing works.
voices.nejm.org/doi/full/10....
The NEJM needs to vet its OpEds better. And Paul Sax MD
needs to learn how mask fit testing works.
Testing made possible by a grant from #kanro
All test results dedicated to the public domain.
For comparison, a 3M Aura 9205+ scored 83 Pascals under the same test conditions, so can get good breathability from masks other than duckbills.
Leaks under the seal of a mask can make it seem more breathable than it is. The filtration result of 97.8% for the 1804 leaves open the possibility that there may have been a small amount of face seal leak even though the simultaneous PortaCount test gave an N95 mode fit factor of 200+.
The masks were fitted tightly to a silicone mask testing headform attached to a Scince SC-MBT-2032 filter testing machine set to test at 85 lpm.
The accuracy of the testing depends on getting a good mask seal on the headform. Results should be considered approximate.
I tested breathability by measuring how much vacuum pressure in Pascals it takes to draw air through a mask at 85 liters per minute of airflow. The less vacuum pressure needed, the more breathable a mask is. So lower numbers are better.
But, not all duckbill masks are super breathable, as you can tell from the bar chart. The Giko 1440 was the least breathable at 154 Pascals. That is not terrible, but it is well above the ≤100 Pascal most breathable mask tier defined by the new Canadian CSA standard.
Why are duckbills so breathable? The shape of the mask allows for more usable surface area for air to go through than some other mask designs, allowing for easier airflow.
You can buy VFlexes in boxes of 50 for about $37. The surgical ones are harder to find and are typically sold through medical suppliers.
There are small size VFlexes to fit people with smaller faces. But they have less surface area, so they don't score quite as well for breathability.
The 1804 is an FDA approved "surgical" N95, which has increased splash resistance that can make make a mask less breathable, but not in the case of the 1804. The non-surgical version, the 9105, tests about the same and is also super breathable.
Duckbill N95s are super breathable masks that are very protective, but which one is the most breathable?
The most breathable one I tested is the 3M VFlex 1804 Surgical Duckbill N95, testing at a very low 57.8 Pascals.
Surprisingly, it is thicker than others but still more breathable.
The one thing I've run into with my wireless home internet is that it is by the same provider as my cell phone. So when there is an outage, I can't get data from my phone or my home internet.
I wish I had wireless home internet through a different provider than my cell service.
Feline induced paralysis is definitely a thing. A doctor's note should not even be required.
www.lunarbaboon.com/comics/soft....
I only know enough to know I don't know enough about any of it.
And I was surprised to learn how complicated distilling alcohol can be and that methanol is more concentrated in the head and tails of the output of a still, so sloppy distillation can poison people doing home distillation of their own fermented alcohol.
I've always been confused about how bad moonshine and methanol are related.
I was surprised to read in The Poisoner's Handbook (a book on the development of forensic chemistry) that it was the US Government poisoning people deliberately during the prohibition with methanol.
I got nuthin'...but boy are those some seriously long whiskers!
You can still use them in addition to a well fitted mask, but some of the companies, such as Pure Enrichment, tend to imply the purifiers are more effective at creating a localized bubble of clean air than they actually are.
The AirFanta 4Lite is the best in class for portable air filtration designed to create localized clean air zones, but even with that there are significant limitations and you need to be really close.
youtu.be/29wInO_8Bi8
There's an explainer in the YouTube Short
youtube.com/shorts/KCXeV...
I really wish small air purifiers were better at making a local clean air zone, but unfortunately the filtered output becomes almost instantly mixed with the unfiltered ambient air.
The air is only 1.6x cleaner of submicron particles 6" from the output of this purifier.