Mar 06, 2023

COVID mask guide: As omicron surges, N95 and KN95 are safer than cloth

The omicron variant of the coronavirus may spread more quickly and efficiently, and now that it is the dominant strain it's worth reconsidering use of cloth masks. In some places, such as Minnesota and California, wearing masks indoors is mandatory again. Along with vaccines and testing, masks remain one of the CDC's three main tools to fight the coronavirus. But what material is best? How do they filter particles? And how should you care for them?

Health experts now warn against common cloth masks and recommend masks that produce an electrostatic charge, like N95, KN95 and KF94 materials. Here are a few key questions and things to consider when reassessing your mask strategy.

Homemade masks are less effective at protecting the wearer because most have spaces known as voids near your nose and cheeks where tiny droplets can be inhaled. The pores in the fabric alone are generally not small enough to trap tiny aerosolized droplets. A research paper published in PeerJ looked at the surface of 20 different types of cloth masks and found that pore sizes ranged from 80 to 500 micrometers. For comparison, the novel coronavirus is about 0.12 micrometers.

To give yourself the best shot against omicron, upgrade your masks.

Many countries, including Austria, Germany, and the Czech Republic have mandated the use of N95-style respirators.

Respirators, like the N95 mask, 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 where 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.

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 are not designed for people with facial hair. However, N95 respirators still offer the best respiratory protection for bearded men, according to a study, though it may be variable. While protection by KF94 and KN95 is brought down considerably by the longer beard, they still proved better options than cotton face masks.

Filter mechanisms aid in collection of both larger and smaller particles. Surgical masks and N95-style respirators are constructed from flat, nonwoven mats of fine fibers. Diameter and thickness of the fibers, as well as porosity (the ratio of open space to fibers) play a role in how well a filter collects particles. The four mechanisms are inertial impaction, interception, diffusion, and electrostatic attraction.

The main difference boils down to what country or organization certified the standard of quality for the masks. N95 masks are certified by the National Institute of Occupational Safety and Health, while KN95s meet standards specific to China. KF94 masks meet the Korean standard requirements.

Wondering where you can buy the mask? USA TODAY gathered some options for you.

Leave a used mask at room temperature at least for 3-4 days. All viruses should be dead by then. Best is to isolate the mask in a breathable location:

According to the CDC, the N95 that has blood, nasal secretions, or other bodily fluids on it should be discarded and not reused. The same goes for the mask with broken straps or broken nose pieces.

Never use cleaning products such as Lysol, alcohol or bleach. Liquid, including soap and water, can damage the mesh of electrically charged fibers designed to catch particles and droplets.

While the best option remains the N95 mask, it might not be possible to find the one that fits a child. St. Jude Children's Research Hospital recommends children 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.

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 the mask with others.

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. Wash your hands regularly with soap and water or use hand sanitizer.

Contributing: Shawn Sullivan, Javier Zarracina.