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 […]
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.