Informing Homemade Emergency Facemask Design: The Ability of Common Fabrics to Filter Ultrafine Particles

Eugenia O'Kelly; Sophia Pirog; James Ward; P John Clarkson

Repurposing material for homemade face masks comes with its own risks. Particular consideration should be given to respiratory hazards which may arise from the material used to construct a homemade facemask. For example, concern has been expressed that certain HEPA vacuum bags include fibers which, if inhaled, can cause lung injury. Fabrics which shed lint may also lead to lung damage if worn regularly. For this reason, we would caution those needing to create homemade face masks to ensure all material is safe, nontoxic, thoroughly prewashed, and lint-free. Fabrics which readily shed fibers may not be suited for face mask construction. The risks associated with such materials are an important area of further study, as large numbers of people are currently creating, wearing, distributing, and selling homemade facemasks. Further research should also evaluate the ability of these materials and material combinations to filter specific viruses, pollutants, and other harmful airborne particles. Additional research on homemade facemask fit and fit testing is also critical at this time.