Evaluation of particle filtration efficiency of commercially available materials for homemade face mask usage

The COVID-19 pandemic has resulted in a severe shortage of personal protective equipment. The World Health Organization (WHO) and the US Centers for Disease Control and Prevention (CDC) recommend the general public to use cloth masks as a protection for individuals and reduce the transmission of the disease. Here, we evaluated the size-dependent filtration efficiency of submicron particles and the overall filtration efficiency (total rejection of particles) of multiple commercially available materials in the size range of 17-700 nm. Single-layer samples of woven fabrics such as cotton and polyester have overall filtration efficiency of 12%-22%. Blended fabrics filter 11%-48% of particles. Products manufactured from cellulose have filtration efficiency of 29%-33%. Materials commonly found and used in hospitals remove 20%-63% of particles and filtration efficiency of filter materials ranges from 40% to 96%. Particle filtration of materials becomes more efficient when individual materials are stacked and used as multiple layers. Different combinations of woven, nonwoven, and blended fabrics were evaluated and have overall particle filtration efficiency of 38%-63%. Results in this study highlight the importance of using multiple layers in homemade masks to enhance filtration efficiency. Commercially accessible materials like Halyard sterilization wrap and blackout drapery lining show the best filtration performance among all tested single-layer materials and therefore are recommended to use as one of the layers in homemade masks. Universal mask wearing - regardless of whether an individual is infected - will help reduce transmission risk. Copyright (c) 2021 American Association for Aerosol Research