Are cloth face masks effective?

Face masks have long been used to help protect against disease, but the effectiveness of a mask’s protection can not only depend on the mask itself but the person you ask. In March 2020, Lisa M. Brosseau, ScD, a national expert on respiratory protection and infectious diseases, discussed that cloth face masks offer no protection from the SARS-CoV-2 virus, commonly known as COVID-19. To many, especially in a time of pandemic, this stance seemed controversial. However, through factual science, there is a reasoning behind her belief that other experts agree upon as well.

In March 2020, Lisa M. Brosseau, ScD, a national expert on respiratory protection and infectious diseases, discussed that cloth face masks offer no protection from the SARS-CoV-2 virus.

The Science Behind the Mask

In any expiratory activity, such as talking, aerosols (a suspension of particles in the air), or commonly referred to as droplets especially if larger in size, are created and propel away. When a person coughs or sneezes, actions such as these can produce larger droplets that propel from them even further. If a person has an infection, such as by a virus that is able to reside in these droplets, they can potentially spread the virus to others when these droplets fall to the ground or on surfaces that then come into contact with others or if others are within the vicinity of the suspension. There are many details about the different sizes and characteristics of the transmissions of these droplets as well, but this is typically where face masks come into play as they are believed to provide a physical barrier to prevent the spreading of droplets.

As many know, when a person coughs or sneezes, actions such as these can produce larger droplets that propel from them even further. If a person has an infection, such as by a virus that is able to reside in these droplets, the virus can easily spread.

The effectiveness of a mask depends on the type of mask

There are two common types that are FDA regulated: surgical masks and N95 respirators.

A surgical mask, also known as a medical mask, is typically loose-fitting and disposable that includes specified layers of material that are moisture resistant. They are mostly designed to provide protection against large droplets that form through activities like sneezing. However, most surgical masks do not filter small particles and due to its loose-fitting design—forms a leakage of airflow around the edge of the mask.

N95 respirators are tight-fitting disposable masks that are designed to form a seal on your face and includes a specialized filter that captures at least 95 percent of particles that are 0.3 microns or larger that pass through it. They are more effective than surgical masks as they can filter both small and large particles and form the above mentioned sealing fit around your face.

Between these two types of masks, it is the N95 respirator that is greatly recommended for protection. In a case of a pandemic, however, shortages of these regulated masks can ensue which leads to the need and use of alternatives, most commonly through cloth masks and coverings.

The efficacy of cloth masks has been met with controversy

The efficacy of cloth masks has been met with controversy and conflicting studies. Although some experts believe that the use of cloth can offer sufficient protection, others do not — “Cloth masks in my opinion don’t work in any form. They aren’t very good at source control, except for maybe very large particles. And they should not be used in healthcare settings for a number of reasons.” said Lisa M. Brosseau in an April 2020 interview with Infection Control Today.

With the CDC recommending the use of cloth face masks at the time of her statement, it was a stance easy to question. Understanding the desired function of masks can however paint a clearer picture. Like typical surgical masks, cloth face masks are commonly loose-fitting; allowing air around the sides which unfortunately gives way for the passage of droplets. The difference between the two is that the FDA regulated surgical masks are typically comprised of moisture-repelling layers which helps to protect against large droplets. These surgical masks are also intended for one-time uses which is better than reusing. With many cloth masks or coverings generally not designed or specially tested to impede particles sufficiently, they may offer little to no protection.

“Cloth masks in my opinion don’t work in any form. They aren’t very good at source control, except for maybe very large particles. And they should not be used in healthcare settings for a number of reasons.” said Lisa M. Brosseau in an April 2020 interview with Infection Control Today.

To date, there is actually a lack of sufficient research

To date, there is actually a lack of sufficient research on the effectiveness of cloth masks as a whole. There was a circulating study, published in April of 2020 in the Annals of Medicine journal, that suggested that cloth face masks were more effective than surgical face masks. This further prompted this narrative and discussion, especially in the internet community. However, this study is now retracted as there were errors in their study that made their findings uninterpretable.

With other studies such as a 2015 study and a 2020 study suggesting that cloth face masks were inferior to surgical masks and respirators, it can be easy to understand the discouragement of cloth mask use — so why would the CDC recommend them?

All masks are not made equally

The fact of the matter is that all masks are not made equally. N95 respirators are the clear-cut masks that offer the best protection. However, these masks along with FDA regulated surgical masks should be reserved first for health professionals and first responders; especially in any case of shortage and pandemic as these professionals encounter infected individuals more than the general public.

Cloth masks or coverings are better than nothing as they can possibly disrupt a cloud of droplets from coughs and sneezes and at the very least, may give a visual trigger to reinforce the practices of social distancing.

When these masks are not available for use, cloth masks or coverings are better than nothing, though, as they can possibly disrupt a cloud of droplets from coughs and sneezes and at the very least, may give a visual que to reinforce the practices of social distancing. This does not mean that cloth face masks do not have the potential to be more effective. There is evidence, that other experts conclude with, that high-quality cloth face masks may provide adequate protection with the appropriate material, layers, fit, and design. More research needs to be done in this area, but it may give a sense of hope that specific cloth face masks may emerge as a quality and conventional alternative in the future.