Chicago Sun-Times (Sunday)

FIRM AND FITTING

Why N95, KN95 masks are much more effective than cloth versions

- BY KARINA ZAIETS, JENNIFER BORRESEN, STEPHEN J. BEARD AND RAMON PADILLA USA Today

The Omicron variant of the coronaviru­s spreads much more easily, and now that it is the dominant strain, health experts are warning against wearing cloth masks and recommendi­ng N95, KN95 and KF94 masks instead, which produce an electrosta­tic charge and are far more effective.

Why skip cloth?

Homemade masks are less effective because most have spaces known as voids near your nose and cheeks where tiny droplets can be inhaled.

And the pores in the fabric alone generally aren’t small enough to trap tiny, aerosolize­d droplets.

A research paper published in the journal PeerJ looked at the surface of 20 different

types of cloth masks and found that pore sizes ranged from 80 to 500 micrometer­s. But the coronaviru­s is only about 0.12 micrometer­s.

Why N95 masks are so effective

Respirator­s — including N95 masks — are designed to achieve a close facial fit and efficient filtration of airborne particles.

They have a denser network of fibers than surgical or cloth masks. N95s are made of a polypropyl­ene material that goes through a process in which it’s melted and extruded through small-diameter holes into hundreds of tiny fibers that are tangled together.

The fibers are then charged by passing them through a device that produces static electricit­y. The charge makes them 10 times better at capturing particles.

But the key with the N95 is proper fit: There should be no air gaps or voids around the nose, cheeks or chin.

With the proper fit, masks approved by the National Institute of Occupation­al Safety and Health can filter up to 95% of particles in the air. They also do a great job of filtering your own exhalation­s to protect others.

N95 masks aren’t designed for people with facial hair. But N95 respirator­s still offer the best respirator­y protection even for bearded men, a study found, though exactly how much protection it might offer them can vary.

Protection with KF94 and KN95 was brought down considerab­ly by longer beards, but they, too, still proved to be better options than cotton face masks.

Filter mechanisms aid in collection of both larger and smaller particles.

Surgical masks and N95-style respirator­s are made from flat, nonwoven mats of fine fibers. Diameter and thickness of the fibers and their porosity — the ratio of open space to fibers — play a role in how well a filter collects particles via four mechanisms: inertial impaction, intercepti­on, diffusion and electrosta­tic attraction.

N95, KN95 and KF94’s difference­s

The main difference boils down to which country or organizati­on certified the standard of quality for the masks.

N95 masks are certified by the U.S. government’s National Institute of Occupation­al Safety and Health.

KN95s are manufactur­ed in China and meet standards set by China.

KF94 masks are manufactur­ed in Korea to meet that country’s requiremen­ts.

Reusing an N95 mask

Leave a used mask at room temperatur­e at least for three to four days. By then, any viruses should be dead, experts say.

The best practice is to isolate the mask in a breathable location such as a paper bag — do not use a plastic bag. Close the bag, and allow it to sit at room temperatur­e for at least three to four days.

Wash your hands after handling the used masks and bags. Assign one bag for each day of the week. By the time you get back to Monday, it will have been seven days since you wore last Monday’s mask, and it should be safe to reuse.

Handling cloth masks

If you wear a cloth mask, be sure to wash it. Most fabric masks can go into the laundry with your clothes and should be washed using detergent and hot water “when it gets dirty or at least daily” according to the federal Centers for Disease Control and Prevention. Tossing them into the dryer on hot is also recommende­d.

Throw out any frayed or loose-fitting cloth masks. Avoid cloth masks made from dry clean-only fabric or fabrics such as vinyl, which make it difficult to breathe.

When not to reuse a mask

According to the CDC, any N95 or KN95 mask that has blood, nasal secretions or other bodily fluids on it should be discarded and not reused.

The same goes for any mask with broken straps or broken nose pieces.

Never use cleaning products such as Lysol, alcohol or bleach to clean an N95 or KN95 mask.

And liquids — including soap and water — can damage the mesh of electrical­ly charged fibers designed to catch particles and droplets.

N95s for kids

While the best option remains the N95 mask, it might not be possible to find the one that fits a child. So St. Jude Children’s Research Hospital recommends that kids wear duck-bill N95 masks because cloth masks “do not provide the same level of protection and should not be used.” The white duck-bill N95 mask comes in two sizes, small and regular, and is shaped outwardly like a duck’s mouth. The design was created to offer better breathabil­ity.

If this mask is unavailabl­e, it’s best to opt for a kid-sized surgical mask. According to the CDC, be sure the child’s mask fits snugly over the nose and mouth and under the chin and that there are no gaps around the sides.

It’s important to make sure the mask is the right size to cover the nose, mouth and chin and fits snugly but comfortabl­y. Show kids how to wear the mask properly, and teach them not to touch the front of the mask and not to pull it under the chin or into their mouth.

They should store the mask in a bag or container, and not share it with others.

How else to protect against Omicron?

Get a booster shot if you haven’t already to give your body the best chance at defense against the virus.

It’s also still important to maintain social distancing. Avoid poorly ventilated spaces. Where possible, open doors and windows. And wash your hands regularly with soap and water, or use hand sanitizer.

 ?? STOCK.ADOBE.COM ?? The key with the N95 mask is proper fit: There should be no air gaps or voids around the nose, cheeks or chin. With the proper fit, masks approved by the National Institute of Occupation­al Safety and Health can filter up to 95% of particles in the air.
STOCK.ADOBE.COM The key with the N95 mask is proper fit: There should be no air gaps or voids around the nose, cheeks or chin. With the proper fit, masks approved by the National Institute of Occupation­al Safety and Health can filter up to 95% of particles in the air.
 ?? STOCK.ADOBE.COM ?? Health experts now warn against common cloth masks and recommend masks that produce an electrosta­tic charge, like N95 and KN95 (pictured) styles.
STOCK.ADOBE.COM Health experts now warn against common cloth masks and recommend masks that produce an electrosta­tic charge, like N95 and KN95 (pictured) styles.
 ?? STOCK.ADOBE.COM ?? Cloth masks provide the least amount of protection against virus transmissi­on but are better than no mask at all, experts say.
STOCK.ADOBE.COM Cloth masks provide the least amount of protection against virus transmissi­on but are better than no mask at all, experts say.

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