Multiple layers of specific combinations of every-day fabrics were found to provide excellent filtration efficiency (FE), particularly when it came to the smallest aerosolized particles emitted during speech. The new study suggests that, in the right combination and layers, with no gapping around the perimeter, cloth face masks help reduce viral transmissions. The study was authored by scientists with the University of Chicago and Argonne National Laboratory in Lemont, Illinois.

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    The high-filtration rates of the top-performing samples, out of the 15 tested, were likely due to their combined effect of both mechanical and electrostatic-based barrier and filtration. This refers to the static electricity sometimes felt when handling polyester nits. "Polyester woven fabrics can retain more static charge compared to natural fibers or cotton due to their lower water adsorption [adherence to surface] properties," according to the study.