COVID-19 has changed since it first emerged. So has some of the advice about ways we can protect ourselves. From the beginning, “wear a mask” has been a mantra – and that hasn’t changed.

Along with handwashing, social distancing and vaccines, experts still agree that wearing comfortable masks that fit well helps stop the spread of COVID-19. But the Centers for Disease Control and Prevention  (CDC) has changed its guidance on masks.

The agency is careful not to promote one mask over the other. But their overview of masks  highlights why one face covering offers more protection than cloth and procedure masks (better known as surgical masks). It’s the N95.

What Makes an N95 Different?

An N95 is actually a respirator — not a mask. Unlike a cloth or surgical mask, it’s made from a dense mesh of tightly woven plastic fibers. The mesh fiber also has an electrostatic charge. The charge actually attracts and traps foreign particles, including virus particles. A particle can be captured mechanically, by the mesh fiber, or electrostatically. The N95 basically stop the particles in their tracks.

As a result, N95 face coverings are much better than other face coverings at trapping large and small droplets exhaled by the wearer. They also block particles from the outside. A properly fitted N95 can filter up to 95 percent of particles in the air. In contrast, loosely woven masks made of cotton or synthetic fabric blends are more low-tech and can’t do as good a job of blocking the particles.

N95 Buyer Beware

True N95s are certified by the U.S. National Institute of Occupational Safety and Health. Sadly, the counterfeit market is huge. N95 knockoffs don’t meet the quality standards of the originals. Unfortunately, it’s hard to know if an N95 is fake.

Recently, the Biden administration has offered free N95s at popular retail sites. But many of these masks are not packaged properly, or have been removed from their wrapping. Thrown in open bins and displayed on open store shelves, they could be contaminated.

To protect yourself, experts suggest buying them straight from reputable sellers.

Pay Close Attention to Fit

When choosing an N95, make sure it fits properly. The CDC offers a downloadable PDF  that offers tips on how to check the fit. It also gives information about how to handle and care for your N95.  

No Shortage of N95 Masks

At the beginning of the pandemic, the CDC advised anyone who wasn’t a frontline worker against wearing an N95. There was concern that demand could create a dangerous shortage. In January 2022, the agency updated its advice, saying a shortage of N95 masks “is no longer a concern.”

Do You Still Need to Wear a Mask if You’re Fully Vaccinated?

Yes. The CDC recommends wearing a mask indoors in public and outdoors in crowded areas or when you’re in close contact with people. In the U.S., everyone also needs to wear a mask while on planes, buses, trains and other public transit. 

Sources: Recharging or rejuvenation of decontaminated N95 masks;  AIP Physics of Fluids, 2020; Your Guide to Masks,  Centers for Disease Control and Prevention (CDC), 2022; How to Protect Yourself and Others,  CDC, 2022;  How Well Do Face Masks Protect Against COVID-19,  Mayo Clinic, 2022