From QuiltingDigest.com. The latest test results show that one of the most effective fabrics is … quilting cotton. Tightly woven, high-quality quilting cotton can block 70 – 79% of air born particles. 

According to the New York Times “The best-performing designs were a mask constructed of two layers of high-quality, heavyweight “quilter’s cotton,” a two-layer mask made with thick batik fabric, and a double-layer mask with an inner layer of flannel and outer layer of cotton.”

The biggest challenge of choosing a homemade mask material is to find a fabric that is dense enough to capture viral particles, but breathable enough that we can actually wear it. Some items being touted online promise high filtration scores, but the material would be unwearable. A simple light test can help you decide whether a fabric is a good candidate for a mask. “Hold it up to a bright light,” said Dr. Scott Segal, chairman of anesthesiology at Wake Forest Baptist Health who recently studied homemade masks. “If light passes really easily through the fibers and you can almost see the fibers, it’s not a good fabric. If it’s a denser weave of thicker material and light doesn’t pass through it as much, that’s the material you want to use.”

Dr. Segal, of Wake Forest Baptist Health, noted that quilters tend to use high-quality, high-thread count cotton. (Way to go quilters!)

The best homemade masks in his study were as good as surgical masks or slightly better, testing in the range of 70 to 79 percent filtration. Homemade masks that used flimsier fabric tested as low as 1 percent filtration, Dr. Segal said.

Yang Wang, an assistant professor of environmental engineering at Missouri University of Science and Technology, worked with his graduate students to study various combinations of layered materials.

Dr. Wang’s group found that when certain common fabrics were used, two layers offered far less protection than four layers. A 600 thread count pillow case captured just 22 percent of particles when doubled, but four layers captured nearly 60 percent. A thick woolen yarn scarf filtered 21 percent of particles in two layers, and 48.8 percent in four layers. A 100 percent cotton bandanna did the worst, capturing only 18.2 percent when doubled, and just 19.5 percent in four layers.

Dr. Wang’s group studied two different types of filters to use in home made masks. An allergy-reduction HVAC filter worked the best, capturing 89 percent of particles with one layer and 94 percent with two layers. A furnace filter captured 75 percent with two layers, but required six layers to achieve 95 percent. 

The problem with air filters is that they potentially could shed small fibers that would be risky to inhale. So if you want to use a filter, you need to sandwich the filter between two layers of cotton fabric.

At Embroidery by EdytheAnne’s shop, we have several partial In The Hoop Machine Embroidery designs, both adults and children. They can be found at this link: InTheHoopEmbroideryDesigns.com