Since the start of the COVID-19 pandemic, health agencies in the United States have recommended face mask usage to limit the spread of the novel coronavirus.

Dr. Teresa Amato, director of geriatric emergency medicine at Northwell Health, told Healthline that even as experts scramble to understand a pandemic that was virtually unheard of 6 months ago, mask wearing is a no-brainer in terms of decreasing transmission.

“It’s especially true with the more people you have wearing a mask,” she explained. “If you are infected and you wear a mask, you will decrease the likelihood of transmission. You’re wearing it to protect the people around you and you’re also wearing it to protect yourself from getting it. It’s really important to emphasize that more people wearing masks will decrease transmission overall.”

When it comes to specific masks, they can range from a simple folded bandana to hand-sewn cloth masks to N95 respirator masks.

While N95 masks provide a high level of protection, they aren’t a realistic option for most people, as they should be earmarked for frontline workers. Amato also points out that they aren’t exactly a one-size-fits-all option.

“N95 masks need to be fitted, and the wearer needs to be fit-tested to make sure that it’s on there appropriately,” she said. “Otherwise, wearing one is actually not very useful. So we’re not talking about the N95, we’re talking about either surgical masks or cloth masks.”

Verma and his team sought to find out which non-N95 masks would be most effective.

He said that the simplest masks — either a bandana or handkerchief — were virtually ineffective.

“I was a bit surprised to see how much leakage could occur through the bandanas and folded handkerchief masks we tested, even through multiple folds of the cotton fabric,” he said.

Ultimately, Verma and his colleagues determined that the most effective homemade masks were those that were well-fitted with multiple layers of quilting fabric.

Cone-style masks also worked well.

“Quilting cotton, with two layers stitched together, turned out to be the best in terms of stopping capability,” said Verma. “For minimizing the chances of transmission, it is important to use masks made of good quality tightly woven fabric, as well as mask designs that provide a good seal along the edges without being uncomfortable.”

Amato says another useful mask option, for those who can obtain them, are simple surgical masks.

“In the beginning, we were kind of holding onto those for healthcare workers, but now we have a good supply of them,” she said. “They’re probably the most comfortable to wear. They’re very lightweight and they afford good protection.”

Medical reference: Healthline