How Long Can You Wear a KN95, N95, or KF94 Mask Before Replacing It?

In November 2021, the U.S. government SARS-CoV-2 Interagency Group (SIG) classified Omicron as a Variant of Concern (VOC). By April 2022, the Omicron variant overtook Delta to become the dominant strain of COVID-19 in the U.S., making up all coronavirus infections. The reason? While experts aren't sure why, the variant is not only more transmissible than previous strains, and it's better able to evade vaccines, leading to more breakthrough infections.

These two factors are why some experts recommend upgrading their face masks from cloth coverings to the more robust protection of a surgical mask or what's known as a respirator (think: N95, KN95, or KF94 masks).

But a change in mask also requires changing how you use and care for that mask. Those who have gotten used to washing their cloth masks, for example, will have to get used to throwing out surgical masks after every use if they decide to switch.

Dealing with a respirator is a bit different, though: You can't wash them, but they also aren't single-use—so how exactly do you care for these pieces of personal protective equipment (PPE)?

Here, experts help explain how often you should be changing your N95, KN95, or KF94 masks and whether there's any legitimate way to clean them because a face covering is only as effective as how well you use and take care of it.

Can You Reuse a Respirator? How Long Can You Wear a KN95, N95, or KF94 Mask?

If you typically wear cloth masks, you're probably used to washing them and reusing them; for surgical mask users, you're (hopefully) tossing them in the trash after each use.

Respirators kind of fall in between the two options: You can reuse respirators (without washing in between uses), as long as you're aware of your risk level and you take care of the mask between uses, Cassandra M. Pierre, MD, MPH, an infectious disease physician and medical director of public health programs at Boston Medical Center, told Health.

There's no hard-and-fast rule about how many times you can wear a respirator before throwing it away. Instead, it's more important to track where you wear the face covering and for how long.

For people who wear their masks for shorter periods or in situations where they remain physically distant from others throughout the day, Dr. Pierre said that it's possible to use the same respirator for up to a week. But for people in high-risk settings, like healthcare facilities, it's best to toss the mask after a day.

Of course, each time you use a respirator—if you're reusing it—you should make sure it's still in good condition. "We recommend every time you use a respirator, you're making sure there are no tears, gaps, or evidence of soiling on the surface," Dr. Pierre told Health. "All these things can impair the integrity and filtration ability of the mask."

Some key ways exist to tell if your respirator has lost its integrity:

• Not snug enough. If the mask has loosened on your face and no longer has a tight seal, it should be replaced and not reused, Jade Flinn, MSN, a nurse educator for the Biocontainment Unit at Johns Hopkins Medicine, told Health.
• Dirty. If the mask is visibly dirty on the inside from makeup, body oil, sweat, or other forms of moisture, you should also toss it, said Flinn.

How Should You Store KN95, N95, and KF95 Masks Between Uses?

Since you can wear a respirator more than once—and because cleanliness is an important factor in reusing your mask—you'll want to store them properly between wears.

• Proper Removal. That starts with how you take your respirator off, with clean hands and by the ear straps, so you don't touch the front, which may have accumulated some virus particles. The CDC provides easy-to-follow directions on the proper removal (and handling) of respirators.
• Proper Storage. Once you've removed the mask from your face, you'll want to store it in a safe, clean space—not in your purse or in your car's rearview mirror. "Keep it away from anything you'll be touching," said Flinn. "Putting it in a paper bag, so it's covered and not getting mixed up with other things can help, along with helping it dry out." According to Dr. Pierre, a plastic food storage container works too, but only if you keep the lid slightly open to prevent condensation on the mask. A harder container can also help retain the structure of the mask.
• Proper Refitting. When it's time to put your mask on again, wash your hands, then carefully inspect it for damage. If everything looks OK, use the straps to put it on, and avoid touching the outside of the mask. Ensure the respirator fits your face snugly, then rewash your hands.

Can You Disinfect or Clean Your KN95, N95, or KF95 Mask To Reuse It?

Unfortunately, no ways to disinfect or clean respirators are available to the general public, according to Flinn. Any potential ways to clean N95 or other respirators—an area of research health agencies are still looking into—require specific strategies only available in laboratories or other healthcare settings.

One study that often gets attention regarding the decontamination of respiratory masks was published in April 2020 on medRxiv, a preprint server for research that has not yet been peer-reviewed.

The study from the National Institutes of Health (NIH) found that four decontamination methods were able to eliminate various levels of "detectable viable virus" from N95 fabric: vaporized hydrogen peroxide (VHP), 70-degree Celsius dry heat, ultraviolet light, and 70% ethanol spray. The decontamination techniques are helpful in health care settings when respirators are in low supply but aren't really beneficial for the general public.

There is some science behind storing a respirator in a paper bag between uses, though. While those in healthcare settings ideally only use a respirator once, the CDC recognized the shortage of N95 respirators at the beginning of the pandemic and offered options to healthcare workers. In January 2022, the CDC clarified that people could choose respirators such as N95s and KN95s without concerns about supply shortages for N95s.

One suggestion was to store the mask in a paper bag for a minimum of five days. The CDC instructed healthcare workers to have five N95 respirators for each day of the week, storing them for a minimum of five days between uses. According to the CDC, this provided time for some pathogens on the mask to "die off" while in the bag. But even then, the CDC recommended N95s weren't worn more than five separate times.

How Can You Properly Dispose of Your KN95, N95, or KF94 Mask?

Throwing out your used N95 or other respirators starts exactly how storing them does: Use clean hands to remove the mask from your face by the ear straps, and be careful not to touch the front of the mask.

Then, it's right into the trash. According to the Environmental Protection Agency (EPA), masks and other types of PPE cannot be recycled and should be kept out of recycling bins. And while it might be tempting just to toss your respirator and be done with it, the EPA notes you should throw it out "securely" so someone else doesn't come into contact with it.

A Quick Review

Masking is an important public health strategy for preventing the spread of COVID-19. Experts remind us that any mask is better than no mask. If you are using a respirator, following these best practices will keep you safer and keep your respirator effective at protecting you and others.