What Are KN95 Masks?

KN95 Masks: What You Need to Know

Choosing the right face mask for your safety (and the safety of those around you) can be confusing. What do all those different numbers and letters mean? And which type of masks do you really need? One of the most common masks available is the KN95, which you can find in our Safety Supplies section. Here's some information about what a KN95 mask is, how it's different from other types of masks, and a few recommendations on how to choose the best mask for your needs.

What Is a KN95 Mask?

"KN95" is a designation for Chinese-made filtering facepiece respirators that meet China GB2626-2006 performance standards. Filtering facepiece respirators (FFR) are disposable face masks that are subject to a variety of regulatory standards, with different countries and regions having their own specific designations. The standards that KN95 masks are subject to include physical and performance characteristics that they are required to meet.

According to a 3M technical bulletin (PDF) from January 2020, KN95 respirators must meet the following performance standards:

  • ≥ 95% efficiency
  • Flow rate of 85 L/min
  • ≤ 8% total inward leakage
  • ≤ 350 Pa inhalation resistance
  • ≤ 250 Pa exhalation resistance

This is not an exhaustive list but provides some of the key standards that masks must meet under GB2626-2006.

How Is a KN95 Mask Different from an N95 Mask?

In the United States, FFRs are regulated by the National Institute for Occupational Safety and Health (NIOSH). The N95 respirator is the most common of seven types of FFRs approved for use in the U.S., and specific types of N95 masks are cleared by the Food and Drug Administration (FDA) for use as "surgical N95 respirators." This means that they are approved for use in a healthcare setting. Note that not all N95 masks are cleared for surgical use.

The underlying difference between a KN95 mask and an N95 mask of any type is the performance standards that they were designed to meet. While KN95 masks meet Chinese standards, N95 masks are required to meet United States NIOSH-42CFR84 performance standards, which are closely comparable. Both, for example, are required to have filter performance that is at least ≥ 95% efficient. The FFP2 (Europe EN 149-2001) respirator meets similar European standards.

Due to shortages of N95 face masks in the U.S., the FDA authorized the use of non-NIOSH-approved N95 respirators, including (as of April 3, 2020) KN95 respirators from China, when needed.

Why are people concerned about KN95 masks?

The greatest concern surrounding KN95 masks is whether they are suitable for hospitals and health care settings. Due to the potential for close contact exposure to those who are ill, it's critical that these masks meet all performance standards to protect those who use them. A mask that meets KN95 standards should perform very similarly to an N95 mask, blocking 95% of particles, including bacteria and viruses. These masks should be tight and well-fitted, creating a seal around the nose and mouth to minimize leakage as much as possible.

What Is a Medical Mask?

Medical or surgical masks differ significantly from filtering facepiece respirators. These disposable masks are designed to be loose fitting, unlike FFRs, and while they are fluid-resistant and effective at filtering out some airborne particles, they do not provide the full protection that an FFR offers. The FDA offers a useful comparison between surgical masks and N95 respirators at https://www.fda.gov/medical-devices/personal-protective-equipment-infection-control/n95-respirators-and-surgical-masks-face-masks.

Surgical masks are regulated by the FDA under 21 CFR 878.4040. They are designed to block large particles and spray or splatter, preventing them from reaching the nose or mouth.

Should I Wear a KN95 Mask?

The CDC does not recommend that the general public wear N95 masks; due to the limited supply, these FFRs should be reserved for healthcare workers and first responders.

In everyday situations, including going to a non-medical work environment or store, other types of face coverings – including KN95 masks, 3-layer protective masks, and cloth face masks – are recommended. Wearing a mask that fits closely to the face can help reduce the spread of viruses to others, particularly when other social distancing practices are followed as well.

KN95 masks that meet all regulator standards provide more protection than homemade cloth masks, but they should be used correctly. Use caution when donning or removing a mask; touching the outer surface after the mask has been worn could transfer germs from the mask to your hands. Always wash your hands before putting a mask on or taking it off so that you do not spread any germs from your hands to your face; wash your hands again after removing the mask. A KN95 respirator is designed for a single use and should, ideally, be discarded after use or if it becomes soiled.