calilyliu

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We started a site to make N95s available (aiden.health) because it's been our belief since March that N95s/respirators are the only masks that really work, and everyone should have access to them when we're in the midst of a public health (e.g. everyone health) crisis. 

I've found the muddled advice regarding masking to be quite confounding, and the refusal of retailers to sell N95s to also be counter to the public interest.

Quite simply, masks need to fit, filter, and also be breathable. Filtering vs. breathability is the real design challenge with masks (theoretically speaking, plastic wrap is 100% filtering! The only problem is that it's 0% breathable). And it's been solved pretty well for 20 years with the N95. 

Cloth masks filter 30-50% and they may or may not fit well. 3ply surgical masks are made of material that filters really well, but it has air gaps on all sides. Both are fine if you're in a socially distanced setting, say going for a walk outdoors.

But neither works if you're, say, on a plane packed next to strangers for hours on end.

The recent double masking advice is also a head scratcher.... why not just get an N95? It fits (what the cloth mask in the mask stack is supposed to do) and filters (3ply mask role), and is more breathable and comfortable so you might actually wear it for longer.

The sentiment around price gouging on N95s is also an interesting one. N95s typically have a 25-30% margin for a mask that works. Cloth masks don't really work, they cost less than $1 to make and land, and sell for anywhere between $2 and $30 - so anywhere from a 100-3000% margin for a product that may be fashionable, but ineffective. Curious.

Look for authorized distributors. Unfortunately there's been an issue with counterfeit product being sold at the largest retailers .... 

De jure: KN95 is regulated by China. N95 the US. On paper, all the technical specs are basically the same.

De facto: KN95s are nearly all earloop + folded mask body. N95 is all headband because the CDC thinks earloops are unlikely to fit properly (and therefore filter properly), and has a variety of cup and folded mask bodies.

Also critical to know - but invisible - the N95 standard is much more rigorous on ongoing quality control. With KN95, you can theoretically do things like get your buddy to give you a passing test report, swap out materials, skimp on your production process, and probably get away with it. Much harder to do with N95. Therefore, most people trust N95 more because it's a more comprehensively maintained regulation. The quality distribution of KN95 is therefore much wider than N95 - so there are some great KN95s out there. There's also some garbage product.

Lastly, neither standard regulates the finer points of mask design, like making sure the inside liner is soft and comfortable against your face. That's not one of the technical criteria, but is certainly something you'll care about in hour 3 of wearing your mask on a plane! 

More info here - https://aiden.health/blogs/resources/kn95-n95