In this post we discuss how we think about selecting spunbond nonwoven polypropylene (NWPP) fabrics for washable masks, where we have found spunbond NWPP, and why we’ve chosen Smart-Fab® Double-Thick for our next round of testing. Our Mission Our mission is to share information with the public about the best emerging mask science to help […]
Mask Fabrics: Introduction to Fibers and Fabrics
How Do I Choose Fabrics for Masks for COVID-19? Since March, it seems like there has been a constant barrage of conflicting information about which fabrics are the best for masks for COVID-19. We’ve put together this crash course on mask fabrics to provide some of the fundamental concepts in fabrics and how they are relevant for our collective mask making efforts.
WHO Guidance on Face Masks Changes
Surprising New Guidance from the WHO The WHO guidance on face masks for COVID-19 has changed to include the recommendation that the general public use fabric masks in public settings where physical distancing can’t be achieved and provides specific guidance on mask layers and materials. According to the World Health Organization (WHO), the ideal fabric […]
Fabric Face Masks: Cleaning and Disinfection
Reusable fabric masks should be cleaned and/or disinfected before each use to reduce risks associated with COVID-19 AND other potentially infectious microorganisms (e.g. bacteria, viruses, and fungi). Although the general principles of mask cleaning and disinfection are the same for most fabric masks, details will vary depending on specific mask designs, features, and materials. These […]
A Breathable Combination: An N95 plus a NWPP Mask Cover
As a result of the COVID-19 pandemic, there are global shortages of N95 respirators resulting in large scale adoption of procedures and policies for the extended use and re-use of N95 respirators. In this post we do a deeper dive into the quantitative breathability data for the MakerMask: Cover, a breathable N95 mask cover. The […]
The Big Four: Criteria for Fabric Mask Materials for COVID
This deep dive post looks into the “Big Four” criteria evaluated in preliminary assessments of community mask materials: material characteristics, breathability, water-repellence, and disinfection options. More specifically, we focus on nonwoven polypropylene (NWPP), which is commonly used in commercial face masks. Although ideal medical grade NWPP is not currently available for community use, NWPP is commonly available at different weights and grades for other household and/or commercial purposes, such as reusable grocery bags. Here we take a more in-depth look at the 4 preliminary criteria considered when evaluating potential sources of NWPP.
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.