There may be a lot we still don’t know about COVID-19, but there’s plenty we do. We know it spreads mainly from person to person through the respiratory droplets that are produced when an infected person coughs, sneezes or speaks. We also know that wearing a mask is a great way to block those droplets from entering the air and infecting others.

According to the Centers for Disease Control and Prevention, when they’re used along with other preventive measures, including social distancing, frequent handwashing and cleaning and disinfecting frequently touched surfaces, masks clearly help reduce the spread of COVID-19. So the question is no longer should you wear a mask; the question is what kind of mask should you wear?

Researchers from Duke University published results from a recent study on that very subject in the journal Science Advances. They tested 14 commonly available masks and mask alternatives. Each test was performed with the same protocol, with the wearer repeating the same sentence for approximately 40 seconds while the droplets they emitted were recorded. Here’s what they found:

Bandana

The study found that a simple bandana cut the droplet rate in half, which is certainly a positive thing. But not nearly enough to curb infection.

Neck Fleece/Gaiter

When testing a neck fleece or “gaiter,” the researchers found that the material tended to disperse the largest droplets into a multitude of smaller ones, which actually increased the droplet count over no mask at all. When you consider that smaller particles are airborne longer than large droplets (larger droplets sink faster), the use of these types of masks might actually be counterproductive.

Cotton Mask

Using a cotton mask provided much stronger droplet control in the study. The subjects’ speech patterns were no longer recognizable and most of the droplets, compared to the control trial, were blocked by the mask.

In addition, there was information released from the CDC regarding vented masks, here’s what the article had to say:

Vented Mask

A vented mask is another type of popular mask, but they have been found to be less effective at stopping the spread of COVID-19 to others. This is because masks with one-way valves or vents allow air to be exhaled through a hole in the material, which can result in expelled respiratory droplets that can reach others. Therefore, CDC does not recommend using masks for source control if they have an exhalation valve or vent.

So if we look at the mask types reviewed in the Duke University study and CDC article, it’s clear that the most effective choice to protect yourself and others is with the cotton cloth mask. Bandanas, vented masks and gaiters, on the other hand, simply do not provide the kind of droplet reduction and spread prevention that the CDC and others recommend.

At Mount Carmel, we’re not just sharing this guidance; we’re taking it to heart. With the health and safety of all our colleagues, patients and visitors in mind, we’re no longer allowing vented masks or gaiter-style face coverings in any of our facilities. If you’re wearing either of these mask types when you arrive, we will gladly provide you with a more protective ear-loop mask instead. Because the more we know, the better we’ll do.

And to learn more about how to wear your mask correctly, please read our blog post here.