Recommendations and Guidelines for Extended Use and Limited Reuse of N95 Respirators in Healthcare Settings

An N95 mask is designed to hug your face, and is meant to keep out particles. You can see the edges are molded to fit over your mouth and nose when you look at one. Surgical N95 masks are a type of N95 filtering respirator used a lot in healthcare. They protect against breathing in tiny infectious bits when taking care of sick individuals, like during the COVID pandemic starting in 2019.

Background: In the era of COVID-19, there were a lot of healthcare workers who would hardly miss an N95 respirator among their protective gear. True to this, they’re actually made with an idea that one has to safeguard himself from inhaling minute particles that can be breathed in like viruses and bacteria.

This article explores recommendations and guidelines for extended use and limited reuse of this protective kit in healthcare settings. These instructions are based on the latest evidence-based science and best practices. They will help ensure the safety of health care providers while adapting available supplies of respirators during scarcity periods or surges such as in COVID-19 times.

Researchers found that health workers who wear N95 respirators continuously throughout a shift are less likely to get respiratory virus infections. On the other hand, medical masks that are worn all the time cause wetness to build up inside the mask, which makes it less effective at filtering.

Photo by Seth Shay Martin from Johns Hopkins medicine

COVID-19 is basically spread through aerosols and droplets. So, it's important to look at the particle properties and their behaviour in air, i.e aerodynamic behavior. When people who are infected with COVID-19 sneeze, cough, or even talk, they release viral plumes that contain thousands of droplets, ranging in size from 0.6 to 100 μm per cubic centimeter. All sizes of aerosol droplets can fly up to 7 to 8 meters if the temperature and humidity are just right. SARS-CoV-2 is about 0.1 μm in size, which is kind of the same as most viruses. When the airflow is 85 l/min, the N95 respirators can catch 95% of particles smaller than 300 nm. Also, N95 respirators were better at protecting against particles smaller than 20 μm than surgical masks. This meant that estimates of their effectiveness ranged from 2% to 92%.

Photo from Public Health UIC

When it comes to respiratory protective gear like N95 masks, using them at the right time is key to getting the most efficiency for your patients in terms of staying healthy. N95 respirators seem to do a better job fending off those respiratory infections compared to those hospital-blue surgical masks when worn on the job.

Apparently moisture builds up inside the surgical masks when you wear them all day, getting the inner layer damp. This moisture then diminishes the mask's filtration capability over time. To this end, reports indicate that facial masks or respirators leaks constitute the primary mode via which medical personnel are infected with viral diseases when they come across aerosolized microbes or germs while on duty. On this line, a good number of experts believe that even though your chosen RPE has a high splash protection front, it will not save you unless it forms a enough seal around your face. Well-fitting RPE is crucial. For instance, how well N95 respirators cover your face is alleged to be one of the key elements that determine whether these devices will provide you with any protection at all or not.

However, there is a bit of a downside when wearing a N95 mask. If you wear these masks for a very long time, they can cause physical and mental problems and make you less productive at work. It is quite difficult to carry out an activity for as long or as effectively when N95 masks are worn compared to when they are not. When masks and PPE are worn, an action can only be done for a shorter amount of time. If you wear a mask for a long time, it can cause headaches, dry nose, eye irritation, and skin problems like rashes, acne, and burning.

Definition: As the name suggests, extended use means using the same N95 respirator for multiple close encounters with more than one patient without taking it off between each interaction. The N in N95 means the National Institute for Occupational Safety and Health of the United States, NIOSH, for short and 95 indicates the filter efficiency of particles i.e 95% efficient.

When many people are sick with the same lung disease or respiratory pathogens and are placed together in special waiting rooms or medical areas, extended use of N95 respirator may be used. Extended use has been approved as one of the ways of maintaining respirators during previous respiratory pathogen pandemics and outbreaks.

Image credit; Towfiqu barbhuiya on Unsplash

Photo by Nancy Sabin from ISHN

Definition: Reuse happens when you use the same N95 respirator with different people but take it off (called "doffing") after each visit. The respirator is put away between patients so that it can be "worn" again before the next patient visit. Non-emergency reuse has been practiced for decades for fighting off pathogens that are not spread through contact, like fomites. For example, to avoid TB, the CDC says that a person can use a disposable respirator again as long as it still works and is used according to the guidelines for controlling infections in that area. 

There are limits on how many times the same N95 respirators can be reused, even when reusing it is allowed or encouraged. Reusing a N95 respirator is often called "limited reuse." During earlier respiratory pathogen outbreaks and pandemics, limited reuse has been suggested and widely used as a way to save up respirators.

The people in charge of an institution's respiratory protection program should decide whether to allow extended use or limited reuse of N95 respirators. They should do this after consulting with their occupational health and infection control departments and getting feedback from the state and local public health departments. Whether or not to use these practices should be decided on a case-by-case basis, taking into account the respiratory pathogen's characteristics and local conditions. Some healthcare facilities might want to use respirators more than once or only a few times before they run out so that they have enough on hand when demand is high. For normal (non-emergency) scenarios, you should also look at the most recent CDC recommendations for that pathogen.

Some people think that longer use and reuse of respirators could help save limited stocks of disposable N95 respirators, but some people are worried about these practices. Not all devices have been approved by the FDA to be used again. Some makers' product user manual says for single use only, while others say it can be used again if the facility's infection control policy allows it. Most of the risks come from touching the surface of the contaminated respirator. As a result of long-term use, one study found that nurses touched their face, eyes, or N95 mask 25 times on average each shift. Contact transmission can happen directly with another person or indirectly by touching and contaminating surfaces that are then touched by other people.

Respiratory pathogens on the surface of the respirator could be passed to the wearer's hands by touching them, which could then affect the mucous membranes face when they touch it again (this is called self-inoculation). Studies have shown that some respiratory pathogens can stay active on respirator surfaces for a long time. However, more than 99.8% of these microbes stayed stuck on the respirator after touching it or simulating a cough or sneeze. Vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA), norovirus (NV), clostridium difficile (CDIF) among many others as well can also pass on to respirators from patients who carry these common healthcare pathogens. These pathogens survive for long periods in the environment. The person who wore the mask could get these organisms on their hands, which would then be passed on to others through direct or indirect contact transmission.

When respirators are used more than once, the risks of contact transmission can change depending on the medical procedure being done and how well engineering and administrative controls are in place. These controls affect how contaminated a respirator is by droplet sprays or the deposition of aerosolized particles. For example, medical procedures that create aerosols, like bronchoscopies, sputum induction, or endotracheal intubation, are likely to make the surface of the respirator more contaminated. To lower the levels of contamination, source control of patients (for example, asking them to wear facemasks), use of a face shield over the disposable N95 respirator, or engineering controls like local exhaust ventilation are likely to be effective.
The main risk of prolonged use and reuse of respirators is contact transmission, which happens when you touch a contaminated respirator. Other concerns have also been looked at, such as the respirator's decreasing ability to protect the wearer due to rough handling or excessive reuse. Extended use can make people feel worse if they have to wear the mask for longer than normal. This should be acceptable, though, and shouldn't pose a health risk to people who are properly cleared to wear respirators.

Photo by Ingrid Hein from MedSpace

Surgical N95 Respirators are a type of N95 Filtering Facepiece Respirators (FFRs), often called "N95s." They are commonly used in healthcare areas. Now, let's look at some general N95 respirator precautions we should know;

Using N95 masks longer or reusing them can help stretch supplies at hospitals and clinics, particularly when there's not enough on hand or there's a lots of demand. If these healthcare facilities stick to the right recommendations and guidelines, they can safeguard their staff and still get more mileage from their stash of respirators.

Recommended Guidance for Extended Use and Limited Reuse of N95 Filtering Facepiece Respirators in Healthcare Settings. 2020.

Kumar Shubhanshu, and Avaneesh Singh. “Prolonged Use of N95 Mask a Boon or Bane to Healthcare Workers during Covid–19 Pandemic.” Indian Journal of Otolaryngology and Head & Neck Surgery, 25 Jan. 2021,

Alkhalaf, Ali, et al. “Efficacy of Surgical Masks versus N95 Respirators for the Prevention of COVID-19 in Dental Settings: A Systematic Review.” Cureus, vol. 15, no. 4, 16 Apr. 2023,

Health, Center for Devices and Radiological. “N95 Respirators, Surgical Masks, Face Masks, and Barrier Face Coverings.” FDA, 15 Sept. 2021,