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Show HN: I bought and tested the filtration of every mask on Amazon

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Re: Show HN: I bought and tested the filtration of every mask on Amazon

#101

Post by lloydarmbrust »

BugsJustFindMe wrote: post #81
lloydarmbrust wrote: post #71

Earlier quoted context omitted.

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?

You 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.

Not 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.

Re: Show HN: I bought and tested the filtration of every mask on Amazon

#102

Post by lloydarmbrust »

pjgalbraith wrote: post #61
nkurz wrote: post #19

Wow, this is fabulous! They spent almost $5000 to buy and test every mask available on Amazon. If you click on a mask it will take you to a page with the test details. More incredibly, most of the masks also have 5-7 minute video review! If you click on the "Breathability" column, then on "Grade" twice, you will end up with a list of masks that Pass with the most breathable masks first. Way to go, Lloyd. I've never h…

A lot of content marketing these days is low-effort and spammy but this is a great example of content marketing done well.

Haha thanks.. this one got out of hand. People kept asking me if x or y mask was "good" and I was just really curious... one day I looked up and had tested more masks than the CDC.

I learned so much though about how different manufacturers do things, where they cut corners, where they invest.

One crazy thing I learned was that almost all of the KN95s on amazing were not following the GB2626-2019 ("KN95") mask spec.... even though it's not that hard. So I decided to make a KN95 that followed the spec! Great way to really get into the product.

Re: Show HN: I bought and tested the filtration of every mask on Amazon

#103

Post by wrycoder »

lloydarmbrust wrote: post #101
BugsJustFindMe wrote: post #81

Earlier quoted context omitted.

You 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.

Not 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.

How did you determine those percentages?

Re: Show HN: I bought and tested the filtration of every mask on Amazon

#104

Post by lloydarmbrust »

pimlottc wrote: post #53
lloydarmbrust wrote: post #13

Earlier quoted context omitted.

Thanks for noting, this was our old methodology and I will get that updated ASAP. We are now removing the subjective feedback and only talking objectively: 1) Does the mask pass the claimed PFE (particulate filtration efficiency) standard that it claims to pass? 2) Does the mask pass the claimed breathability (as stated in the standard they are claiming, ie N95, KN95, surgical)? 3) Does the mask meet other parts of t…

With regards to #3, I found it a bit incongruous that you failed some KN95 masks (like Boncare) for incomplete labeling, while allowing a mask to pass that met a standard that appears to be entirely of their own devising (the Lutema M95i [0]). This seems to be a bit unfair, given that they both performed well in the PFE and breathability tests. It seems like if Boncare decided to call theirs an “MN95” mask, it would…

A few things. The PFE test I'm doing is a 2min test and doesn't tell you what the mask will do under load (all day use). It's really a simple way to tell if the mask sucks but not if the mask is good (if that makes sense).

If someone doesn't label the mask correctly...are they even reading the standard?

The gb2626-2019 standard is 57 pages and in it you have to do a lot of very technical testing. One test requires several days of testing in a lab and is very expensive, but it's designed to make sure the mask performs under actual use (called the loading test).

If the manufacture isn't willing to put some simple words on a mask, do you think they did this complicated several-day test? Probably not.

IMO it's the brown M&M or canary in the coal mine test.

Re: Show HN: I bought and tested the filtration of every mask on Amazon

#106

Post by thro1 »

dpark wrote: post #74
thro1 wrote: post #66

Earlier quoted context omitted.

If you can't catch it (but the mask does), you can't spread it..

Because of course people wearing vented masks wear them whenever they are near another human. It’s not like they have family or friends they spend time with maskless.

Sad, but true. Those who don't care had to leave..

Re: Show HN: I bought and tested the filtration of every mask on Amazon

#107

Post by wrycoder »

lloydarmbrust wrote: post #71
wrycoder wrote: post #55

Earlier quoted context omitted.

Your filtration test appears to be only testing the mask fabric, but not the fit. I see a number of surgical masks over 95%. I don't think that would be possible in practice, because of leaks at the sides and top. I'd expect more like 50%. But, you don't appear to have the equipment to do a fit test. Refer to the 3M video on how to fit test an N95. I realize that N95 and surgical masks have different standards, but y…

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?

You 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.

Re: Show HN: I bought and tested the filtration of every mask on Amazon

#108

Post by bee_rider »

I was lucky enough to find some of those 3M Auras at a local hardware shop. They are like $2 a pop, but everything about them is nice -- materials feel great, I find the inside volume is enough that I can breathe easily, they don't stick out like a beak (IMO having the beak style ones in my field of view is annoying). 10/10 mask, still hope to not need them sooner or later, but given the state of the world would buy again.

Re: Show HN: I bought and tested the filtration of every mask on Amazon

#109

Post by jcun4128 »

jcun4128 wrote: post #34

Well... that sucks (finds the brand I've been wearing all this time).

Was funny today at the post office this old guy took his mask off, cleared both nostrils like blowing with his fingers and put his mask back on like wtf... Oh well. Then he touches the pad that you pay with oh man...

Re: Show HN: I bought and tested the filtration of every mask on Amazon

#110

Post by throwaway81523 »

cpeterso wrote: post #56
halpert wrote: post #50

Earlier quoted context omitted.

No, but if everyone is wearing one it doesn't matter. Some of the masks on this site are vented as well.

Most of the point of wearing a mask is to prevent you from unknowingly spreading COVID to other people. Many stores I visit have signs prohibiting vented masks.

I've been wearing a surgical mask on top of a valved N99 some of the time. That seems to satisfy. Maybe I could put more serious filtration material over the valve though.

I would like to find some affordable PAPR's (powered air purifying respirators). I see a number of places claiming to make them, but none seem that actually available to buy.

It might be interesting to measure the amount of CO2 inside a mask after a person has been wearing it for a while. There are some differences between mask types, but I don't know if any would appear between mask brands and models. Here is a study where they tested some masks that way:

https://bmcinfectdis.biomedcentral.com/articles/10.1186/s128...

I have a CO2 sensor on order from Adafruit and while try doing some tests like this myself when I can.

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