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A good mask needs both fit and filtration... most people can put a mask on, check for air gaps and see how well it fits, but they don't have a $250k mask lab to
by lloydarmbrust 5y ago
A good mask needs both fit and filtration... most people can put a mask on, check for air gaps and see how well it fits, but they don't have a $250k mask lab to make sure the fabric is good.
We are just solving for the filtration and letting people figure out the fit.
But, you make a good point, in the videos I try to point this out but we could do better. Where could I add this to make this more clear?
- deleted 5y ago[deleted]
- BugsJustFindMe 5y agoYou could start by adjusting your given filtration ratios by predictable leakage based on the type of mask. It's wholly misleading to rate the filtration potential of an earloop mask as equivalent to that of a 3M Aura.
- lloydarmbrust 5y agoNot exactly.. it really depends on the situation. For example an ASTM 2 or 3 surgical mask fabric has a filtration of 98%+ On my face I have a leakage of about 21% or PFE of 79% when worn normally. With an ear saver, it jumps to 91%. With a mask brace, it jumps to 98%. So it really is about the fit. If I put leakage % it would vary from person to person and many people would be mislead by this.
- wrycoder 5y agoHow did you determine those percentages?
- lloydarmbrust 5y agoUsing the industry standard TSI PORTACOUNT® RESPIRATOR FIT TESTER 8048 It measures the air outside the mask verses inside the mask. https://tsi.com/products/respirator-fit-testers/portacount-respirator-fit-tester-8048/ https://tsi.com/products/respirator-fit-testers/portacount-r...
- creato 5y agoDo you have the same measurement for you for an N95 with the typical elastic straps that you can share?
- lloydarmbrust 5y agoYes but it differs from model to model. I get as low as 80% and as high as 99% on my face. Fit is a big deal because it's personal and hard to communicate. I think it was Amazon that found when scanning their workforce that they discovered 29 different face shapes!
- divbzero 5y ago> On my face I have a leakage of about 21% or PFE of 79% when worn normally. > With an ear saver, it jumps to 91%. > With a mask brace, it jumps to 98%. I had no idea it could vary so much for surgical masks. I’d be curious what range of leakage people could typically expect for other designs such boat-shaped KF94 or flat-fold KN95 masks. Fit seems important enough to deserve a mention in the intro paragraph at the top of the home page. A more detailed explanation, including the example you gave of how much it can vary for even one person, could go in the “Click here” link to the full testing methodology. Thank you for doing this, by the way, rare to see a manufacturer test so far beyond their own masks. It clearly takes resources to do this and is a great service to all of us who have been relying on guesswork.
- lloydarmbrust 5y agoOkay I put a disclaimer right on the front and we are typing up an explanation right now. Thank you for this feedback! https://www.armbrustusa.com/pages/mask-testing https://www.armbrustusa.com/pages/mask-testing
- bagacrap 5y agothanks! all the notes about fit will be very helpful, including how to use the extra accessories you mentioned above. For example I found this study on beard length which made me reconfigure my facial hair: https://www.nature.com/articles/s41370-021-00337-1 https://www.nature.com/articles/s41370-021-00337-1 The charts in that paper also make it seem that n95 *typically* has a much better seal on the face which is worth noting. I also wonder if the breathability you're measuring affects filtration, given imperfect fit. I would imagine that worse breathability would cause more air to flow around the mask rather than through it.
- deleted 5y ago[deleted]
- wrycoder 5y agoYou could add a clear statement to the testing procedure popup that you are measuring the fabric only, and that (except for N95) the filtration of a mask is strongly dependent on fit and leakage.
- lloydarmbrust 5y agoOkay working on this now.. thanks for the suggestion. I should note that even N95 is extremely effected by fit. I've gotten as low as 80% filtration on a flat-fold N95.
- lloydarmbrust 5y agoDone
- Scoundreller 5y agoUnhhh, fit and leakage matter a lot for N95 too.
- 3np 5y agoI think it should be made way more clear - and here I take the opposite stance of the person you're replying to. Change title to "Comprehensive Mask Material Testing" or "Comprehensive Mask Fabric Testing" or similar. Similarly; "...that's why we're testing the filtration capabilities of every mask in our laboratory" At some point (on the front page, above the fold) there could be a small notice box explaining the difference, or ?-link or tooltip to read more. I think a lot of the suspicion you're facing in this thread wouldn't have been there if it weren't for that ambiguity, and the need to go into deep content to resolve it. For someone who just browses to your site and spends 5 min finding "the best mask", they would never realize as it is today.
- lloydarmbrust 5y agoThese are good points. Working on rewording this now.
- lloydarmbrust 5y agoOkay I put a disclaimer and typing up a post to link to LMK what you think: https://www.armbrustusa.com/pages/mask-testing https://www.armbrustusa.com/pages/mask-testing
- 3np 5y agoHey, I think it's a lot more clear now :)
- lloydarmbrust 5y agowoot
- wrycoder 5y agoThanks! https://www.armbrustusa.com/blogs/news/mask-fit-vs-filtration-importance https://www.armbrustusa.com/blogs/news/mask-fit-vs-filtratio... Oh, excellent update! (It might be a good idea to break your database into two sections: one for N/KN/KF respirators and one for other masks.) I also notice that you have a "collections" page https://www.armbrustusa.com/collections/ https://www.armbrustusa.com/collections/ That page has a very helpful section, "USA made N95 masks and KN95 respirators". https://www.armbrustusa.com/collections/usa-made-n95-masks-respirators https://www.armbrustusa.com/collections/usa-made-n95-masks-r... Exactly what we need. Two questions: 1. Aren't all N95 "masks" actually respirators? 2. Why do you offer "made in USA" KN95 (Chinese standard) instead of an Armbrust branded N95? Thank you for doing this!
- bjarneh 5y ago> but they don't have a $250k mask lab to make sure the fabric is good Hard to argue against that, but on HN I'm sure someone's gonna try :-)
- TrueGeek 5y agoSomeone on HN recently did: https://news.ycombinator.com/item?id=29878971 https://news.ycombinator.com/item?id=29878971
- lloydarmbrust 5y agohahaha got me on that one.
- pcl 5y agoPerhaps you could add a “fit ease” row to your scoring? Masks with head straps could have a check and others could have a ? or something.