Are KN95 Masks Reusable?

Despite the relatively fast rollout of the COVID-19 vaccine this year, masks continue to be essential features of the new normal. Whether you’re visiting your local supermarket or catching a flight, masks are still mandatory in many public places. While there are several different types of masks, KN95 and N95 are some of the more popular choices due to their effectiveness in filtering out airborne viruses.

After sterilization with plasma vapor hydrogen peroxide, KN95 masks have a 95% filtering efficiency rating. However, when exposed to chlorine dioxide sterilization, this efficiency rating reduces to 76.2%. This drop in efficacy shows that they are susceptible to wear and may not be consistently effective in combating infectious diseases.

Although they are designed to be used once by a single person, in certain circumstances where there is a shortage of masks, KN95s may be reused. You can clean and maintain them to extend their lifespan. However, it is difficult to ensure safety after reuse. It’s important to realize that filters might become worn after multiple cycles of sterilization. Further testing is necessary to confirm the exact point at which the masks wear out, but it is currently thought to be after four cycles.

What Are KN95 Masks?

KN95 masks are protective respirators used frequently in construction or manufacturing. They are designed and produced in China but were distributed around the U.S. for emergency use authorization during the 2020 pandemic. The FDA approved them as a solution to global PPE and mask shortages for use in accordance with specific criteria.

KN95s are very similar to the popular N95 respirators used in the U.S. and Europe. They use a particulate filtering system to help people breathe cleaner, particle-free air. According to a report referred to by the National Center for Biotechnology Information, this type of respirator has two key advantages over regular surgical masks. The main advantage is its ability to filter efficiently. The second advantage is the fit.

The KN95 is designed to fit around the face and neck, minimizing the exposure of your face to potentially harmful droplets, particles, and airborne viruses. While other face masks may be effective in filtering air, a poor fit allows breaches.

Despite being the standard version of this type of mask in China, according to the National Institute for Occupational Safety and Health Certification (NIOSH), N95 masks are the most common type of particle filtering respirators in the U.S.

How Do You Know if a KN95 Mask is Suitable for Use?

KN95 masks are designed for one-off use, but they are often reused in various industries when there are mask shortages. Certain measures can be taken to extend the lifecycle and minimize the risk of extended or reuse. However, users should always wear a fresh mask where possible.

If healthcare workers or other professionals who risk exposure to hazardous materials wish to reuse their masks, the most crucial consideration is the effectiveness. This begins when you’re buying your mask. There are some important things to look out for to ensure you don’t purchase a counterfeit:

  • Check the spelling and design of the NIOSH approval stamp and make sure it is correct.
  • Ensure the mask has a headband to fit it, rather than earloops.
  • These masks should have a TC approval number. It is separated with a semicolon and includes a class code (depending on the exact type of respirator), followed by a dash and additional numbers.
  • The company should not claim that children should use their masks.
  • The mask should not contain accessories or decorative extras.

There are many illegitimate KN95s on the market today that are hard to tell apart from genuine products. Around 60% of KN95 masks tested by NIOSH didn’t meet the criteria they claimed to.

Purpose of a KN95 Mask

KN95 masks are personal protective equipment (PPE) that are used for protecting workers. These masks are more common in China than in the U.S., especially when compared to N95 masks. However, KN95 masks are sometimes preferable to surgical masks in situations of extended close contact with those who may be vulnerable to COVID-19, Sars, Cov-2, and other viruses.

According to the CDC, there is a hierarchy of controls that deal with potential hazards. The most effective method on the hierarchy is “Elimination,” which involves physically removing the hazard. Under elimination, there are substitution, engineering controls, administrative controls, and PPE.

While PPE is categorized as the least effective control on the hierarchy, it holds a lot more value in medical situations. Decontamination methods such as physically removing hazards are not always possible in hospitals, but PPE can effectively reduce the spread of respiratory pathogens.

KN95 Masks

Can KN95 Masks Be Reused?

In general, it’s not recommended to reuse N95 or KN95 masks. However, in emergency scenarios such as pandemics, widespread outbreaks of disease, or an infectious respiratory illness, these devices may need to be reused or used for an extended period due to lack of supply. This allows the authorities to conserve PPE supplies, ensuring distribution to high-risk personnel is possible.

The terms extending and reusing are two separate actions, and it’s essential to differentiate what each term means.

Extended use

This is where someone in a medical facility wears the same respirator for several close contact meetings with multiple patients, without removing, changing, or cleaning it in between. Extended use wearing is suitable when there are numerous sick patients with the same hazardous pathogen in specific rooms or wards within an institution. It is also common to recommend extended use if there is a shortage of respirators during emergencies (e.g., a pandemic).


Reuse involves wearing the same respirator for close contact meetings with multiple patients, but the mask is removed after each encounter. The mask is carefully stored in between each session before being put back on for the next meeting.

Masks and respirators have been used and reused in non-emergency scenarios for several decades. The most crucial factor is that the device is still in good condition and serves its purpose.

There are some specific restrictions regarding the reuse of respirators. That means that mask reuse is often described as limited reuse. Like extended use, a recommendation for reuse is usually only to conserve the supply of respirators during emergencies or pandemics.

In most cases, the recommendation is for extended use instead of reuse, the main reason being that it involves less contact between a person’s hands and their mask. Less contact reduces the risk of transmission.

Risks Associated With Reusing Your KN95 Mask

There are several risks associated with the extended use and reuse of KN95 masks. Respirators can lose their shape and ability to function correctly, making them less protective. While this may not lead to grave danger in some industries, respirators must work correctly for health care workers exposed to infectious respiratory diseases.

In manufacturing or construction-based industries, workers sometimes wear their respirators for several hours at a time. This suggests that these masks can be effective for sustained or repetitive use. 

In the medical field, the length of time such items are worn depends on hygiene or practicality rather than a planned or predetermined quantity of hours. If KN95 masks are worn for extended periods or reused, respiratory administrators should put plans in place to reduce the risks of surface contamination. The facility must clearly outline precise guidance of safe procedures to give staff maximum protection and knowledge.

The CDC claims that it’s impossible to know the maximum number of safe reuses for a respirator. This number is dependent on several different variables that affect how a mask works and the level of contamination that they gather.

The most significant risk with wearing KN95 masks for extended periods or reusing them is disease transmission due to direct contact with an infectious patient or indirect contact from contaminated surfaces. Specific respiratory pathogens can survive for extended periods in some environments, making them more dangerous for workers in those industries (e.g., staphylococcus type infections in hospitals).

Medical procedures may also increase the risk of infection transmission, particularly actions such as aerosol-generating medical operations.

Reducing the Risk of Contamination When Using a KN95 Mask

While there is no way to guarantee safety when working in dangerous environments, there are some practical ways to reduce the risk of contamination when you’re reusing or using your mask for an extended period.

Use face shields

Face shields are effective forms of PPE in certain industries, most notably the medical and food sectors. While you shouldn’t wear a face shield in place of a respirator, it is a valuable alternative when a mask isn’t available. In medical scenarios, patients may wear disinfected face shields to help protect them and the medical professional from the possible transmission of droplet-borne infection.

Keep it clean

You should only reuse KN95 masks if they are kept immaculately clean. Ensure that the mask is intact and kept in a sterile, breathable container between uses. Keep an eye on the KN95 or N95 filters and replace them when necessary.

Clean your hands with soap and water, or at least 60% alcohol-based sanitizer before and after touching your respirator at any point. Where possible, use a pair of clean gloves to put on or remove your respirator and ensure it securely fits your face with a tight seal.

Although there are reports that UV light can combat infections such as COVID-19, there is not enough proof that this is an effective way of extending the life of a mask.

Know when to discard or replace your respirator

Despite your best efforts, your respirator may become accidentally contaminated. It’s vital that you know when it isn’t safe for reuse. If the mask is dirty or damaged, you should discard it.

If you come into contact with a patient known to have an infectious disease, you must replace a mask. If a KN95 respirator becomes contaminated with blood, secretions, respiratory droplets, or other potentially hazardous bodily fluids, you must discard and replace the mask as soon as possible.

Contact a Reliable Source for Your PPE Needs

No matter what industry you work in, high-quality PPE is essential for your safety. Unregulated or poorly made equipment can lead to severe illness, injury, or even death. Prioritize safety and ensure that you buy high-quality PPE from a reliable source.

ICU Production Inc. stocks first-rate tested PPE equipment that’s approved by the FDA and CDC. In addition to 3-ply, N95, and Kn95 masks, we can provide you or your business with face shields, gloves, gowns, hand sanitizers, disinfectant wipes, and children’s PPE.