Should you wear an N95/KN95 mask?

The CDC recommends that people wear masks in public settings, when around others who are not part of your household, and when social distancing measures are difficult to maintain. We discuss in a separate post how to choose the right cloth or surgical mask for you. But you may also be wondering whether you should be considering a N95/KN95 mask. 

What are N95 or KN95 Masks?

N95 masks, also known as N95 respirators, are personal protective equipment (PPE) commonly used by doctors and essential healthcare workers. These respirators are named for their ability to filter from the air 95% or more of very small particles. This means that N95 respirators protect the wearer from viral aerosols and droplets in the air. A recent study also found that N95 masks work well at preventing the spread of viruses to others (source protection). This study found that N95s led to the greatest reduction in droplet spread compared to all other masks and no mask controls.  KN95 masks are very similar to N95 masks and are regulated in China. 

N95s need to be properly fitted for best protection.

Healthcare workers who wear N95 masks go through what is known as a fit test, to make sure they are wearing the right size. A fit test is necessary to ensure that healthcare workers are getting optimal protection. An N95 mask that has not been properly fitted still offers more protection than no mask at all. However, wearing an N95 that has not been properly fitted is not recommended.

Should I wear a N95/KN95 Mask?

The CDC recommends that only healthcare workers use N95 masks when caring for patients with confirmed or suspected COVID-19, particularly during procedures that can generate high concentrations of aerosols (e.g. intubation, ventilation). In situations like our current pandemic, N95 and KN95 masks should be reserved for use by healthcare workers so supplies do not run out. Most of us will not be in a high exposure setting where it would make sense to wear an N95 or KN95 mask. 

Currently, we do not recommend wearing a N95 or KN95 mask day to day. Cloth masks, physical distancing, and hand hygiene offer good protection for regular life. As a reminder, the CDC recommends against masks with exhalation valves or vents as these do not help prevent the spread of COVID-19 from the person wearing the mask to others.

Last update: August 16, 2020, 07:13 pm ET

Science review: GSN, ERS