Airpop 'pocket' mask #1 resuable pick of UK's Which magazine

Link to magazine/eZine article - https://www.which.co.uk/reviews/face-masks/article/best-reusable-face-masks-awLeA3A6XoZD

Some of their writeup: 

"It's superb at filtering particles – 99.9% before washing, and 94% after 

five washes. And it’s still light and easy to breathe in"

I've a portacount 8020A. Different setup to theirs.  My portacount can confirm that GVS Eclipse elastomeric masks are actually 99.95% filtration. I burn a candle to fill the room with particles, first, calibrate the portacount, check a known really good respirator that I only use for calibration then head into the tests:

The mask has no nose wire. Instead it has nose-foam on the inside of the mask. My nose is "high nose bridge". The nose foam is shaped to fit such noses it looks like.  I'm dubious, I have to say.

Pics

(PortaCount's port fitted)

Results prior to washing

Set 1: Airpop pocket as is - pre wash - July 06, 2022 18:19:03

Run 1: 98.5563%, ave so far: 98.5563%
Run 2: 98.6622%, ave so far: 98.6264%
Run 3: 97.3017%, ave so far: 97.9517%
Run 4: 93.4926%, ave so far: 96.2845%
Run 5: 94.5791%, ave so far: 95.6007%
Run 6: 93.8148%, ave so far: 94.9862%
Run 7: 91.0821%, ave so far: 93.8427%
Run 8: 93.9208%, ave so far: 93.8636%
Overall Average: 93.8636%
High: 98.6622%
Low: 91.0821%

Set 2: Airpop pocket as is 2 - pre wash - July 06, 2022 18:27:42

Run 1: 90.4873%, ave so far: 90.4873%
Run 2: 93.7041%, ave so far: 92.0691%
Run 3: 87.9000%, ave so far: 90.6501%
Run 4: 93.4510%, ave so far: 91.3719%
Run 5: 87.9832%, ave so far: 90.5886%
Run 6: 88.3621%, ave so far: 90.1791%
Run 7: 93.5164%, ave so far: 90.7200%
Run 8: 90.7812%, ave so far: 90.7289%
Overall Average: 90.7289%
High: 93.7041%
Low: 87.9000%

Set 3: Airpop pocket as is 3 - pre wash - July 06, 2022 18:36:22

Run 1: 89.7479%, ave so far: 89.7479%
Run 2: 93.2735%, ave so far: 91.4958%
Run 3: 90.4800%, ave so far: 91.1440%
Run 4: 91.2295%, ave so far: 91.1656%
Run 5: 90.8403%, ave so far: 91.1013%

At this stage I pressed on the mask. Specifically, compressing the nose foam (no longer "as is") section with my fingers, while leaving the rest of the mask untouched (averages mean nothing from here on)

Run 6: 98.6780%, ave so far: 92.3431%
Run 7: 98.6441%, ave so far: 93.2303%
Run 8: 98.0541%, ave so far: 93.7945% 

Thoughts

The mask is very breathable - no flexing of the fabric on breaths in. It is comfortable too.

The mask started really well at 98% - impressive for something that spunbond polypropylene and nylon of some sort.  I'm just sitting at a desk breathing slowly for this. Typing too, to pass the time. The PortaCount is on the desk and the tubes to the mask have their weight supported so as not to pull on the mask. I'm not reaching for anything or flexing in anyway to dislodge the mask. I've done this 60 times now. I'm also not touching the mask. I don't know why the tests start well and slowly drop 10%. I don't normally do three sets but this was so weird.

I am aware of where there could be leaks against the face though - my eyes can feel puffs of exhaled breaths. Other nose-wire respirators are not doing that.  Hence, part way though the last set, I press on the mask in improve the seal, and the numbers go up again. I think the foam is a big design mistake.

Washing then more tests

From the online guide for the mask (not included in the shipment):

I'm going to trying hand wash, as machine wash suggests "better than 70%" efficiency after and we need better than that.  The hand washing regime doesn't make a claim about efficiency after, but I am going to assume 98% as the Which eZine hints that is a post-washing possibility (see below).

From Which eZine's section on this mask:

It doesn't say how to wash, so I am going to assume hand wash. I've plenty of experience of gently doing so, rinsing and drip drying. So that is what I'm going to do.

Note Which says polyester and and nylon, and not melt-blown polypropylene (conventional disposable respirator choice). However the support document says something contradictory:

Results: Hand washed once with Johnson's baby shampoo - rinsed four times

Run 1: 94.8621%, ave so far: 94.8621%
Run 2: 94.0777%, ave so far: 94.4599%
Run 3: 94.4190%, ave so far: 94.4459%
Run 4: 95.7680%, ave so far: 94.8294%
Run 5: 96.6379%, ave so far: 95.2130%
Run 6: 95.3333%, ave so far: 95.2338%
Run 7: 97.0342%, ave so far: 95.5046%
Run 8: 95.3109%, ave so far: 95.4789%
Overall Average: 95.4789%
High: 97.0342%
Low: 94.0777%

Not good. 

So I've pushed on top of the mask again to compress the nose foam:

Run 1: 97.5794%, ave so far: 97.5794%
Run 2: 97.5780%, ave so far: 97.5787%
Run 3: 96.8644%, ave so far: 97.3399%
Run 4: 97.2917%, ave so far: 97.3277%
Run 5: 97.8720%, ave so far: 97.4415%
Run 6: 97.6179%, ave so far: 97.4716%
Run 7: 97.1413%, ave so far: 97.4334%
Run 8: 97.5085%, ave so far: 97.4429%
Overall Average: 97.4429%
High: 97.8720%
Low: 96.8644%

Much better.

This material hand-washes and retains its filtration pretty well after one wash.