When protecting yourself from airborne pathogens, just about any mask is better than no mask. However, for maximum safety and peace of mind, it’s better to go with a respirator that’s been tested and certified to live up to its performance claims.
In the United States, the N95 face mask is the gold standard for healthcare workers in hazardous conditions. In particular, N95 masks certified by the National Institute for Occupational Safety and Health promise the best protection of anything on the market. However, there’s also the KN95 respirator to consider. Because they look so similar to N95 masks, it’s easy to get confused between the two.
The most basic difference between N95 and KN95 masks is that N95 masks are certified for use in the USA, while KN95 masks are certified for use in China. Of course, that’s just related to the market they end up in, and the vast majority of both are still made in China. The main takeaway is that while the standards are nearly identical, N95 masks have some advantages over KN95 masks, mostly in the consistency department. To understand the functional differences between the two masks, it helps to start with an understanding of how both types work in general.
Both respirator types are made with multiple layers of non-woven polypropylene fibers rated to remove 95 percent of particles measuring 0.5 microns — that’s where the “95” part of the name comes from. Contrary to one popular belief, both types can also be effective at filtering germs and viruses smaller than that, and that’s not just speculation; multiple studies actually back it up over the past 4 years.
There are a few reasons why N95 and KN95 masks are effective at filtering pathogens as small as roughly 0.1 microns. The biggest one is that airborne germs and viruses — particularly the SARS-CoV-2 virus that causes COVID-19 — often cling to other foreign particles significantly larger than 0.3 microns, such as dust and moisture.
Even if you did encounter a lone virus floating free in the air, a properly fitting mask will probably still capture it. This is because of a phenomenon called Brownian Motion, which describes how particles move in the air when they contact other particles. This is heavily simplified, but essentially, if a 0.1-micron virus makes it through the first layer of a respirator, it will still at some point come into contact with one of the layers. Then, instead of bouncing through the mask and exposing the wearer, the minuscule particle would very likely just bounce into another layer of the mask, where it would be trapped, keeping the wearer safe.
One big difference here is the same reason why some masks are better than others in general: The better a mask fits, the better it will be at consistently filtering out pathogens. One major reason why N95 masks are considered slightly more reliable is that an authentic, NIOSH-approved N95 mask will almost always have a pair of headbands instead of ear loops. KN95 masks, on the other hand, almost exclusively use ear loops. As you might imagine, affixing a mask to your skull is significantly more sturdy than attaching it to your ears.
Another reason that N95 masks are mandated for healthcare use is less obvious but arguably more important. As the Emergency Care Research Institute published in September 2020, only 70% of tested KN95 masks met the fitment and filtration standards they’re marketed to meet.
That’s in addition to scattered reports from healthcare workers across the country during early 2020 who claimed that the KN95 masks that were (at the time) authorized for emergency use showed signs of inconsistent production quality and at times, did not fit well. While those claims were and still are anecdotal, they’re still important because they came from professionals and were ultimately backed up by research.
To learn more about some of the best N95 masks and their properties, check out the buying guide on BestReviews.
Both N95 and KN95 masks share a common feature: They are meant for single use only. While some people have documented that washing, sanitizing, and reusing a KN95 mask can still be effective, objective research has not backed up. Neither mask type should be reused if you want to be protected.
With that in mind, both N95 and KN95 masks offer good protection from airborne pathogens compared to cloth or surgical masks, but selecting an N95 mask is a better way to make absolutely certain that you’re getting a good one. Unfortunately, there’s currently no real reason to opt for a KN95 mask in the United States. The biggest reason they were so popular in the USA in 2020 was that supplies of certified N95 masks were running low in virus-plagued hospitals. With that no longer the case, there’s no point in choosing a mask that isn’t guaranteed to be of hospital-grade quality.
This mask is made out of five layers of non-woven synthetic material and officially certified by the NIOSH, and if it’s good enough for doctors, it’s good enough for regular folks too. It’s durable enough to last through an entire day of construction and comes in a variety of bulk packages ranging from 10 units up to 1,000.
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If you need to outfit an entire office of doctors or business workers, this pack of 120 highly effective and CDC-approved masks is a great choice. They fold flat and are about as comfortable as N95 masks get, and each one is individually packaged so you can be sure that it’s brand new and uncontaminated. If you need more than 120, there’s a 440-count case that significantly reduces the price per unit.
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In case you find that other styles get in the way of talking or breathing or rub off too much of your makeup, consider this CDC-approved option. Its round and more rigid construction makes it significantly more comfortable for some users. We’ve highlighted the medium/large size, but there’s also the Makrite 9500-N95S for people with smaller heads.
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This one’s a little different from the rest. It sports a valve on the front that opens when you exhale, which massively reduces the heat and moisture your face is subjected to. However, this makes it mostly unsuitable for use in preventing the potential spread of disease because it won’t filter anything from the air you breathe out. But, if you need a powerful N95 mask for a long day at a construction site or in a workshop, this is one of the most effective and comfortable options.
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Chris Thomas writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.