N95 Masks You Say?

June 25, 2020 6:50 PM

Let minutephysics tell you about The Astounding Physics of N95 Masks.
posted by zengargoyle (17 comments total)

N95 masks are marvels of engineering. It is a crime that in the USA, they are in short supply due to the stupidity of the Trump administration, who could have ramped up production in March but chose not to exercise any Federal powers to keep us safe. In a real country, by now the government would be distributing them to at-risk populations, especially poor groups. Instead of a Federal government response, we have Etsy masks and stylish but nearly worthless bandannas to wear.
posted by benzenedream at 7:05 PM on June 25, 2020 [14 favorites]

That was much more interesting than I expected. Thanks, zengargoyle!
posted by straight at 9:56 PM on June 25, 2020 [1 favorite]

The untold origin story of the N95 mask - "The most important design object of our time was more than a century in the making."

How 3M Plans to Make More Than a Billion Masks By End of Year - "The company is using 'surge capacity' to increase the production of N95 masks to fight the pandemic. Localized supply chains are a secret weapon, too."
posted by kliuless at 11:06 PM on June 25, 2020 [2 favorites]

A billion seems like a large number. Not enough for every American to have 4 masks in a year though.
posted by el io at 12:31 AM on June 26, 2020 [4 favorites]

... and not enough for the rest of the world to have at least one.
posted by JoeXIII007 at 4:41 AM on June 26, 2020 [2 favorites]

Relevant, if we're talking about masks: ABC News: You may want to ditch that valve face mask: The pros and cons

I really thought I had a high-quality, useful mask for this whole situation 'cause it had the N95 label on it & such and it turns out no, not so much. Only just discovered this today through a friend.
posted by scaryblackdeath at 10:12 AM on June 26, 2020 [1 favorite]

Yeah, I have a few of the exhaust-valved N95s leftover from furniture refinishing use before the pandemic. They protect the wearer but not anyone else. Plus, I find that hard plastic valve is always pressed against the tip of my nose and is uncomfortable.
posted by bz at 12:49 PM on June 26, 2020

You can just place tape over the front vent to prevent frontal exhaust.
posted by benzenedream at 3:59 PM on June 26, 2020 [2 favorites]

Five minutes longer than I expected, but very interesting!
posted by snofoam at 6:14 PM on June 26, 2020

Some brands of valve face masks have the exhaust point downwards towards the wearer's body. I don't have mine to hand right now but I think it was the 3M brand one.
posted by kandinski at 8:02 PM on June 26, 2020 [1 favorite]

What we need is a washable N95 mask.

On a side note I really like 3M products. Their stuff always seems like the best example of whatever. Their bandaids are fantastic. Their tapes, abrasives, etc. are just great.
posted by Pembquist at 8:10 PM on June 26, 2020

I've long had a 3M P100 mask with a vent. It vents down, but I still taped it up to not be contrarian. It's far from disposable, has a nice rubber/latex/something seal around the edges and adjustable behind the head straps. I sorta believe the anti-valve thing is because there are so many different types of valves that it's impossible to give good general advice so it's best to just say no to them as a whole. Even the no-valve article said that they went through a filter and then a paragraph later said that they didn't. I can tell you that having a vape-pen I have stood in front of the mirror and watched my exhale through vented and not and cloth and surgical and it really doesn't make a difference. When you inhale, you have negative pressure and the mask sucks to your face (if fitted properly) and all is good. When you exhale it's positive pressure and no common masks are designed for that and they lift and leak out the sides. You need SCUBA or firefighter or clean-room things to filter the exhale because there's nothing else that does that thing beyond catching a sneeze or cough and keeping it from going directly forward. Mask design is around protecting the wearer from the environment, not protecting the environment from the wearer.

Everybody needs to wear a mask because most of their effectiveness is based on that negative pressure and filtering incoming air. The filtering of positive pressure and outgoing air was never a consideration beyond just don't spew it in someone else's face.
posted by zengargoyle at 8:44 PM on June 26, 2020 [1 favorite]

This was an informative video.

"[Germs] don't usually travel on their own. We breathe or caught them out on droplets. ... So the size of the virus or bacteria itself isn't particularly relevant."

This was informative and supplemental to another source of information on masks, SmartAir.
posted by xtian at 7:21 AM on June 27, 2020

What we need is a washable N95 mask.

Elastomeric respirators (half or full face masks, look like "gas masks") and generally used in industry. Run about $30 last I checked, infinitely reusable. Do have replaceable filters, but these are much easier to increase production.
posted by a robot made out of meat at 11:30 AM on June 28, 2020

Elastomeric respirators (half or full face masks, look like "gas masks") and generally used in industry. Run about $30 last I checked, infinitely reusable. Do have replaceable filters, but these are much easier to increase production.

Yes I have always used those in preference to the disposables because I find them more pleasant to wear, (the disposables always smell weird to me and fog up specs, (the less expensive ones without valves,)) and more economical. The reason I want a washable "disposable" is for the current Covid landscape, where a big function of the mask is to interfere with exhaust. At the beginning of the pandemic I wore my 3M half mask until I realized it probably wasn't doing as much as a disposable would to keep me from breathing on people as one reason it is comfortable is that it has an exhaust valve. I don't think it is possible to buy a genuine N95 disposable mask anywhere these days, am I wrong?
posted by Pembquist at 8:40 AM on June 29, 2020

Not in the USA, unless you go to really shady sites and pay $10 per mask. My usual PSA: A functional government not run by idiot manchildren would be handing out N95 masks for free right now to prevent further economic damage from closures. Please GOTV in the fall!
posted by benzenedream at 11:01 AM on June 29, 2020

Regarding functional governments: I live in Taiwan, where the government nationalized the mask industry in early February. They quickly released a scheme whereby everyone with a healthcard (which is almost everybody in the country, of course) was entitled to 2 surgical masks per week (5 for kids). This increased monthly, and now we're at 9 masks every two weeks. Cost per mask: 0.10 USD. There was a smartphone app to tell you which shops had sold out, and which had masks available.

Actually, now things are so ramped-up you can buy a box of 50 masks right off the shelf with no rationing measures in place. N95 and KN95 masks are less-widely available, but can be found easily enough with a bit of shopping around. Nobody wears them, though, because everyone in Taiwan knows that "my mask protects you and your mask protects me" and surgical-type masks are best for that.

Taiwan stats: 24M people, 447 cases (10 active), 7 deaths. No lockdowns, but kids had an extra-long Lunar New Year break from school!
posted by Enkidude at 6:34 AM on July 1, 2020 [3 favorites]