As the omicron variant of the COVID-19 pandemic spreads across the country, finding the right mask to protect yourself has gotten harder within previous months. The Centers for Disease Control and Prevention updated its mask guidance to fight the spread appropriately, advising against cloth masks and surgical masks alone to protect against the virus.

As of press time, the CDC is advising the general public to upgrade to N95 and KN95 masks to protect against the omicron variant. These respirators filter out 95% of particles that are 0.3 microns or larger in diameter, Dr. Michael Schivo, a pulmonologist and an associate professor of internal medicine at UC Davis Health, previously told Men's Health.

Previously reported by Men's Health, the CDC is warning against several N95 respirators falsely claiming to be approved by NIOSH flooding the market, and therefore won't effectively protect you from COVID-19, especially the omicron variant, spread. NIOSH is the National Institute for Occupational Safety and Health (NIOSH) in the U.S., providing the standards for protective N95 face masks across several occupations that require them.

KN95 masks are made abroad in China, thus adhering to Chinese standards. According to the CDC, as many as 60% of KN95 masks available could be fakes.

So how do you know which masks are legit, and even more so where to get one?

ISO/IEC 17025 lab tested

This is a standard recommended by the CDC to ensure the mask meets the protective standards of its country of origin. Check if the manufacturer is listed here.

Visible brand logo and GB2626-2019

The brand of mask should be visible somewhere on the mask itself. Additionally, GB2626-2019 is the mandatory standard for respiratory protection masks.

"GB2626 gives reassurance that manufacturer made mask [with] highest standard per Chinese guidelines," writes Dr. Stella in a comment. "If GB ends in 2006 it’s still legit if not [past the expiration date]."

Shouldn't say "NIOSH/FDA-approved"

To confirm that the KN95 you’re buying is legitimate, make sure the manufacturer is listed on the FDA's Emergency Use Authorization list. The CDC also has a list of NIOSH-approved manufacturers to ensure your mask is certified for your protection. Simply saying so on the box or mask is not approval.

Check the expiration date

Masks absolutely have expiration dates. If the mask you purchased is past its expiration date, you may not be protected.

Make sure the packaging is properly sealed

A banged up or partially opened box is an obvious sign of damage or tampering. Don't use a mask with damaged packaging for your own safety.

No quality control issues

Check if all the masks are identical and there aren't any mix-ups. If not, they're likely safe. to us.

Federal officials at the Centers for Disease Control and Prevention (CDC) updated mask guidance this week to suggest Americans choose N95 or KN95s if possible, as respirators better stem the spread of SARS-CoV-2 spread this winter.Experts have previously confirmed that Omicron spreads at a faster, more effective rate compared to earlier virus variants, and respirators like the N95 provide those in public a boost in subsequent filtration abilities if worn correctly.Tracking the omicron surge• There are plenty of N95 masks, but they're not designed for your kids• Biden says his administration will make free high-quality face masks available to all Americans• What should you do if someone in your family tests positive for COVID-19? An expert shares advice• Health officials are urging you to rethink your face covering and upgrade masksUnlike cloth masks, however, most N95s and even KN95s haven't been designed to be effectively worn more than once. Like surgical masks, these disposable options may carry instructions to be worn once only — yet, medical experts during the PPE supply shortage in 2020 were forced to use them more frequently, and CDC officers have suggested that multiple uses are acceptable. The frequency, and how these masks end up being reused, often varies among experts."I don't think that the extended reuse of an N95 respirator is really a recommended practice by the CDC," says Kimiyoshi Kobayashi, M.D., chief quality officer at UMass Memorial Health, who explains that respirators were commonly sanitized by doctors using hydrogen peroxide gas and UV light in hospital settings. "I wouldn't recommend any of the practices that were used during the pandemic for consumers."Where's the risk in wearing these respirators more than once, you may ask? And if you decide to take federal health officials' suggestions into account, how many times can you safely reuse a respirator mask? We're breaking down below when you should be changing your N95 or KN95 mask and tips for keeping them sanitary as the pandemic progresses. Can you reuse an N95 face mask?Current CDC guidelines published online suggest that respirators including N95s and alternatives like KN95s shouldn't be worn more than five times. Since they need to be fit correctly, however, some health care experts stress that five-plus uses of an N95 or KN95 may be too many. Issues like the elasticity of the masks' ties becoming loose make fitting a respirator mask to the face correctly near impossible, and that's a possibility after just one use.A more concrete rule you may need to follow, according to Dr. Kobayashi, is checking for a soiled or cruddy mask front. "If you were working in a health care setting, a comparable example would be blood splatter or any sort of fluid — in this instance, maybe it's that your N95 has landed in a puddle on the ground. At this point, it shouldn't be re-worn," he says.If you're particularly high-risk for severe complications stemming from a COVID-19 infection, you may wish to skip reusing masks altogether — this is also true for anyone working in a high-risk environment, like hospitals, retirement homes, or high-trafficked public buildings. At the very least, those who choose to wear an N95 or KN95 mask more than once can reduce the risk of any SARS-CoV-2 exposure by storing respirators correctly. Can you clean an N95 or KN95 mask? What's the best way to extend its use? Previously published CDC-sponsored guidance suggests that N95 masks may be cleaned by heating the mask in a dry oven, or boiled without plastic straps, USA Today reports. But it's widely discouraged since it's likely that you'll damage the construction of the mask or, worse yet, start a fire (masks can't be heated above 158 degrees). Rather, Dr. Kobayashi says doctors often used a dry, secure paper bag to "quarantine" masks for at least four to five days after their use. "It's a simple way to decontaminate the mask, as virus particles will no longer be viable or infectious on the mask at this point," he says, adding that the same approach can be used for KN95 masks. You'll need to be sure that your mask remains isolated from other clean, unused options for at least five days for best results. Using this method, Dr. Kobayashi says you can rotate through a few different respirators at a time, working to save your supply if you're having trouble securing more masks for you or your loved ones.Washing a respirator including N95s or KN95s will invalidate their design, as they're not designed to get wet; don't try washing them in the same way you wash reusable cloth masks.

If you're still wearing a cloth or surgical mask when you're out and about, it's time to rethink your face covering.

The U.S. Centers for Disease Control and Prevention (CDC) is set to update its mask advice this week to best reflect the available options and the different levels of protection they provide, a CDC official told CNN Tuesday.

Many experts say cloth and surgical masks don't provide enough protection, and instead encourage N95 or FFP2 coverings.

Upgraded masks are already the norm in much of Europe. Germany mandates FFP2 coverings in stores, on public transport and in other public places. Neighboring Austria made FFP2 masks mandatory outdoors on Tuesday when it is not possible to keep a minimum of 2 meters from people outside one's household, and they have been required indoors since last month.

Italy mandated the heavy-duty masks to enter stadiums, museums, cinemas and theaters, and use public transport from December. And in Greece, anyone who has left self-isolation must wear them in any public place for five days.

The differing terminology for the masks can be confusing, but all the terms refer to the level of filtration offered by the covering — and there's no doubting that FFP2, N95 or KN95 models offer better protection than those made from cloth or other fabrics.

Cloth masks — encouraged earlier in the pandemic — can stop large droplets, while more effective masks can also filter smaller aerosols or particles potentially laden with airborne virus.

Properly fitted N95 respirators that are approved by the U.S. National Institute for Occupational Safety & Health can filter up to 95% of particles in the air, according to the CDC.

A cloth face covering, by contrast, also has 75% inward and outward leakage, which the American Conference of Governmental Industrial Hygienists defines as the "percentage of particles entering the facepiece" and the "percentage of particles exhaled by a source exiting the facepiece," respectively.

People concerned about the best way to protect themselves and their loved ones during this surge of omicron variant cases should "get the highest-quality mask that you can tolerate and that's available to you," Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told CNN's Anderson Cooper on Tuesday, signaling a switch in the official advice.

The issue thus far is that filtration masks are generally more expensive, a bit less convenient to wear and earlier in the pandemic they weren't always widely available.

That explains why the CDC has until now actively encouraged members of the public against buying N95 masks — currently stating on its website that they should be "prioritized for health care personnel."

But Fauci told CNN that "right now, [there] doesn't seem to be any shortage of the masks that some time ago were not available."

"What the CDC has said — and it gets misinterpreted — they're saying, wearing any mask is better than no mask at all," Fauci said. "But there is a gradation of capability of preventing you from getting infected and from you transmitting it to someone else. So we should be wearing the best possible masks that we can get. That's a fact."

CNN's Nina Avramova contributed reporting