A Mask Q&A: Addressing common questions about the KN95, N95 masks and more

With the rise in COVID-19 cases across the country and throughout the state because of the omicron variant, West Virginia University implemented several updated campus health and safety protocols ahead of the start of the spring 2022 semester.

Among the key changes were updated mask protocols. Here, School of Public Health Public Health-General Preventive Medicine program residents – Margaret Karcher, DO, and Vida Falahatian, MD – and PH-GPM Program Director Jennifer Lultschik, MD, help answer some frequently asked questions about masks, including the KN95 mask, recommended by WVU, and N95 mask, used widely in patient-care settings.


Why is the KN95 mask the recommended mask to use right now?

A KN95 mask is made to filter at least 95% of particles of size down to 3 microns in diameter. It permits 8% or less leakage, by Chinese standards.

A medical procedure mask, or surgical mask, fits loosely and will stop large droplets and particles, but does not stop small droplets. Because the omicron variant is so transmissible, a higher level of protection is strongly recommended.

What’s the difference between an N95 and KN95?

KN95 masks originated in China as a counterpart to the N95 respirator and are now made in a number of countries around the world. They are intended to provide protection close to that of an N95 respirator, which is regulated by the CDC National Institute for Occupational Safety and Health (NIOSH). An N95 respirator has straps that go around the head to ensure a tight seal and ideally is fit-tested. A KN95 respirator has ear loops and does not form a tight seal; however, the leakage of air around the mask is much lower than with a surgical mask.

KN95 and N95 masks are both rated to filter out at least 95% of particles down to 3 microns. The N95 is more effective due to being able to achieve a better fit. They have similar resistance to inhalation and exhalation (which affects breathing comfort), with the N95 being slightly less resistant.

Should N95 be reserved for frontline workers or is there no longer a shortage?

Currently the US is not experiencing a shortage of N95 masks; they are widely available. They are usually more expensive than KN95 masks.

What are your recommendations if someone wants to purchase additional KN95 or N95 masks? How do you ensure that whatever you’re purchasing isn’t counterfeit?

A large proportion of KN95 masks and N95 respirators sold in the US are counterfeits, so pay attention to important details, outlined below, before purchasing. These non-approved masks have frequently been shown to be of low quality and not to meet filtration standards.

Red flags that indicate either a KN95 or N95 is counterfeit:  

  • No markings at all on either mask. 
  • A statement that a KN95 is ‘CDC- or NIOSH-approved’.
  • An N95 that has ear loops instead of head straps.
  • No NIOSH TC approval number on an N95.
  • No NIOSH stamp, or incorrect spelling of ‘NIOSH’, on an N95

The FDA created a list of Personal Protective Equipment, which includes KN95 masks, for Emergency Use Authorization (EUA) for healthcare workers early in the pandemic. The EUA is no longer in use, but the FDA list of manufacturer names for KN95 masks that were tested at an accredited laboratory and found to meet filtration standards is still available online:

The CDC has an online list of counterfeit respirators, which can be found here.

Using this information will help you find a quality mask and avoid low-quality counterfeits.

Can KN95 masks be reused? Is it safe to wash to extend its use?

KN95 masks can be reused by the same wearer for several days if they are used and cared for properly. Refer to Guidance on use of KN95 masks for additional information. 

KN95 masks should NOT be washed.

Do KN95s need to be fit-tested to ensure maximum protection?

No. They are not suitable for fit-testing.

Because the KN95 mask has not been certified by the National Institute for Occupational Safety and Health, the Occupational Safety and Health Administration (OSHA) does not consider it a negative-pressure respirator.

How do you properly store an already worn KN95 or N95 that can be used again?

Refer to the guidance provided by WVU for storing your KN95 mask, available in this downloadable PDF

For N95 masks: If worn for an extended period of time, the CDC recommends that users store them in a breathable container such as a paper bag. The container must be clearly labeled (to avoid accidental use by someone else).

Are face shields acceptable? If not, how can we accommodate those who interact with people who are hearing impaired?

Wearing a face shield instead of a mask does not provide adequate protection and is not recommended. Most face shields permit small droplets to travel on air currents around the edges and bottom of the shield, increasing risks to both the wearer and those nearby.

Wearing a clear mask or a fabric mask with a clear panel may be a good idea if you’re going to be engaging with people who depend on lip-reading to communicate. Vinyl and other non-breathable materials are not suggested for masks but may be an exception to the rule for the sake of lip-reading. Alternatives to clear masks are textual communication, closed captioning, or lowering background noise to communicate while wearing a mask that covers your mouth.

How do I properly remove my mask?

Before touching the mask, wash your hands with soap and water or use hand sanitizer.

Depending on the type of mask, adhere to the following:

  • For a mask with ear loops: Gently lift and remove the mask by holding both ear loops.
  • For a mask with ties: Untie the bottom tie first, then the top, pulling the mask away from you as you loosen the ties.
  • For a mask with bands that go around the head: Lift the bottom strap over your head first, then lift the top strap over your head.

After you’ve removed and stored or discarded your mask, depending on its condition, hands should be disinfected with soap and water or sanitizer.

What are some tips/techniques for safely using surgical and/or cloth masks?

If you don’t have access to a KN95 or N95 mask, it is recommended you choose a mask with multiple layers and a nose wire that can be bent around your nose to prevent air leaks. Double-masking should also be considered. Most important: ensure your mask is tightly fitted to your face. Additional tips for putting on your mask:

  • Wash or sterilize your hands immediately before and after putting it on, as well as before and after taking it off.
  • Place the mask on your face, with the moldable nose wire against the bridge of your nose and the bottom of the mask below your chin.
  • Place the mask's straps around each of your ears.
  • Mold the top of the mask to fit the contour of your nose, using both hands to adjust it.
  • Reduce air flow around the mask by adjusting as needed, with the goal of getting a close fit around your face. (For tips on how to achieve this, refer to the CDC’s ‘knot and tuck’ video.)

Keep in mind: Significant facial hair (growth of more than three days) decreases a mask’s capacity to establish a tight seal around your face, reducing its effectiveness in shielding you and others against COVID-19. As a result, it is recommended that all areas of your face that come into contact with a mask, particularly a KN95 mask, should be hair-free.

For additional guidance, visit the Return to Campus website

Portrait photos of Jennifer Lultschik, MD; Vida Falahatian, MD; and Margaret Karcher, DO
Jennifer Lultschik, MD; Vida Falahatian, MD; and Margaret Karcher, DO


CONTACT: Nikky Luna, Director of Marketing and Communications
WVU School of Public Health