People are talking about this controversial Korean face mask. Is it safe?

By Lily Rose

February 12, 2022 / 7:00 AM / Essentials

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The world has seen a number of unusual face masks throughout the ongoing COVID-19 pandemic. There are fish-shaped masks. There are duck bill-type masks. Now, there's a new mask out of South Korea that's getting plenty of attention: The fold-up mask.

South Korean company Atman has produced a foldable KF80-rated dining mask. The "Kosk" is designed to be folded up to cover just the nose, leaving the mouth free to eat or drink. After use, it can be folded back down to cover the mouth.

"Kosk" is a portmanteau, combining the English word "mask," with the Korean word for nose, "ko." It's currently available on Coupang, an e-commerce site based in South Korea. It has not been spotted for sale inside the United States.

Some Coupang reviewers have said that the foldable mask has reduced their anxiety about dining indoors: A wearer's nose can stay covered, even when the mouth is exposed. But the Kosk mask has attracted a lot of attention on social media, where it's been labeled by critics as "the most unhelpful idea and a waste of resources," and just plain unsafe.

'Kosk' makes no sense; reasons being: 1. Doesn't stop the virus entering/exiting the wearer 2. Smell and taste are closely linked. If the ability to smell is reduced, food may seem tasteless!

— Dying Lambaster (@DyingLambaster) February 1, 2022

With so much misinformation about how COVID-19 spreads and what type of masks are most effective, is the Kosk safe to wear?

The Kosk mask may seem like a tempting purchase. Studies have shown that nasal cells are a primary target for the COVID-19 virus, and the Kosk mask keeps the nose area protected at times when it otherwise wouldn't be -- while dining out at a restaurant, for example. But that protection may be an illusion.

KF80 masks have a greater than 80% filtration capability against fine dust. Experts have found that KF80 masks provide protection from bioaerosol particles from breathing, speaking, coughing and sneezing. But here's the catch: KF80 masks are 80% efficient, but only when worn correctly -- that is, when they form a tight seal around your nose and mouth.

A face mask that allows the mouth to be exposed circumvents that level of protection, puts its wearers at risk of inhaling coronavirus-laden droplets and allows the wearer's own potentially infectious aerosols to fill the air. It may be better than going completely unprotected, but there's yet to be a study on how much protection the Kosk mask adds when folded.

The CDC has not recommended the Kosk.

Instead, the CDC continues to recommend wearing a mask that covers the nose and mouth. The CDC recommends wearing the most protective mask available, one that also that fits well and can be worn consistently. The organization notes that well-fitting disposable surgical masks and KN95s offer more protection than cloth masks and that well-fitting NIOSH-approved respirators (including N95s) offer the highest level of protection.

The N95 is a respirator mask that's been tested in the United States for effectiveness. It filters the air the wearer breathes in, rather than, as with a common mask, merely catching large droplets exhaled by wearers. In order to be certified by the National Institute for Occupational Safety and Health (NIOSH), an N95 must filter at least 95% of particles greater than 0.3 microns in size.

Please note: If you run across an N95 mask that does not bear the initials of the NIOSH, then beware: It's not a genuine N95; it's a counterfeit. For more information on face mask fakes, read our guide to spotting counterfeit N95 masks.

Here are some highly rated N95s we found available for purchase.

This new Honeywell design is made to fit more face shapes and minimize pressure points. It comes in a pack of 20.

Honeywell DC300 N95 particulate disposable respirators (20 pack), $30

If you're willing to purchase 50 masks, these, from Kimberly-Clark, have a large breathing chamber for comfort and soft but strong headbands. At just over $1 per mask, these duck bill-style N95 masks are one of the most cost-effective options.

Kimberly-Clark professional N95 pouch respirator (50 pack), $56

Home Depot has several N95 face mask options, including this 25-pack. These N95s have an adjustable nose clip and head strap.

N95 disposable multi-purpose respiratory mask (25 pack), $42

These 3M masks prevent eyewear fogging and have a foam cushion for maximum comfort on a wearer's nose.

3M N95 8210 respirator (20 pack), $27 (reduced from $29)

Lily Rose is a senior writer for CBS Essentials and the site's expert in home appliances such as washers, dryers, refrigerators and ranges. When she's not writing about how you can upgrade your laundry room, she's writing about home and kitchen essentials that will transform your space. Her favorite appliance is her air fryer. She firmly believes that it can make the crispiest sweet potato fries.

First published on February 12, 2022 / 7:00 AM