In this guest blog post Ania Mitros, Ph.D. discusses the laboratory testing data and science behind her preferred fabric combination for masks: two layers of ~65 gsm (gram/m²) spunbond nonwoven polypropylene (NWPP) plus one layer of ~130 gsm woven cotton. Her recommendation comes after reading dozens of scientific publications on the subject and investing thousands […]
Face Masks for COVID-19: Background Information
The MakerMask project team has reviewed extensive literature on the science and manufacturing of NIOSH-approved respirators. We selected a multi-layered design that balanced increased filtration capabilities with permeability for breathing. The spunbond non-woven polypropylene (NWPP) outer layers use the same type of material used in medical-grade commercial masks, providing water-resistance for blocking droplet transmission and mechanical filtration from the structure of the fibers.