Sorry, Your Bandana Might Not Be Protecting You As Much As You Think It Is
A new study found that not all face coverings are created equal.
Along with your keys and phone, face masks have become a must-have for leaving the house — and for good reason. Months into this deadly global pandemic, we now know that they have the power to save lives. But what’s also becoming clear? Not all masks are created equal, and in fact, some masks can actually do more harm than good.
In a recently published study, a group of researchers from Duke University tested 14 commonly available masks or mask alternatives, ranging from hospital-grade N95 respirators to bandanas. They created a basic apparatus using lasers and a camera to analyze how well they blocked particles released from a person’s mouth while talking.
Unsurprisingly, the best face coverings were the masks used by healthcare workers on the front lines: N95 masks without valves.
The great news: Commonly available cotton face masks proved about as effective as standard surgical masks at blocking particles.
The not-so-great news: Certain mask alternatives offer very little protection. “On the other hand, bandanas and neck fleeces such as balaclavas didn’t block the droplets much at all,” according to the Duke Health press release.
In fact, the thin, stretchy, and breathable material used in a neck gaiter or neck fleece (often worn by runners) can actually be worse than wearing no mask at all. That's because the material breaks up bigger particles into smaller particles, which hang around in the air longer, explained Martin Fischer, Ph.D., associate research professor in the departments of chemistry and physics at Duke University in a video produced by Duke Health.
Previous research published in the journal Physics of Fluids also confirmed that "loosely folded face masks and bandana-style coverings" provided minimal protection from respiratory droplets, and that "well-fitted homemade masks with multiple layers of quilting fabric, and off-the-shelf cone style masks, proved to be the most effective in reducing droplet dispersal."
Bottom line: "It's not the case that ‘any mask is better than nothing’,” Fischer said. "There are some masks that actually hurt rather than do good."
So, while we're all for sustainability, you're best off repurposing your bandana as a headscarf or bracelet and skipping single-layer face mask alternatives (including neck gaiters) when possible to slow the spread of COVID-19. (As a basic test, the researchers suggest holding your mask up to the light to make sure you can't see through it.)
Currently, the WHO recommends that fabric face masks should have three layers, and the CDC's DIY mask instructions suggest a double-layer. If you're going the pre-made route, a multi-layer fitted cotton mask is your safest reusable option right now, and luckily, there are plenty of celeb-approved options out there.