Update (February 12, 2021): Thanks to our generous community and a grant from Helpful Engineering, we exceeded our fundraising goal for mask testing! In addition to the originally planned fluid resistance, breathability, and bacterial filtration testing of our fabric combinations, we were able to add mask-level NaCl aerosol filtration tests to our campaign. Thank you […]
Common Approaches to Increasing Seam Strength
Mask Math/Science Vignette: Mask Straps According to the guidance released by the WHO in December mask straps should be designed to withstand at least 10 lbs of force ( 44.5 Newtons). The materials that most straps are constructed from (e.g., cotton straps and silicone bands) easily meet these requirements. However, we’ve seen a number of […]
WHO Fabric Mask Guidance – December Updates
On December 1, 2020, the World Health Organization (WHO) updated their guidance on fabric masks, “Mask Use in the Context of COVID-19 (December, 2020)”, including their “Updated Guidance on Non-Medical (Fabric) Masks” (p. 19-22). This post pulls out key quotes from the new WHO guidance, touching on their recommendations for layering, mask performance standards, and […]
Finding and Selecting Polypropylene for Washable Masks
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 […]
Research Highlights: NWPP Filtration Efficiency from Long et al 2020
This post is the first in a series of “Research Highlights” where we discuss select data and research from the literature in the context of community mask making efforts. In this post, we take a look at the filtration and breathability data for nonwoven polypropylene (NWPP) mask materials presented in: Long KD, Woodburn EV, Berg […]
5 Key Considerations For Window Masks
One of the challenges with face masks is that they often cover key facial features and expressions that are important for communicating speech and emotions. For many people, this means missing out on smiles, and having a little bit more trouble understanding other people in noisy environments. For people that are deaf, hard of hearing, […]
3 Easy DIY Mask Tests
In an ideal world, the safety and efficacy of all of the fabrics and materials used in handmade masks for COVID-19 would be tested using the same standards and facilities used by researchers and large manufacturers. Unfortunately, very few people have access to these resources. In this post we provide instructions for three easy DIY […]
