Silk fabric as a protective barrier for personal protective equipment and as a functional material for face coverings during the COVID-19 pandemic

Abstract

Background The worldwide shortage of single-use N95 respirators and surgical masks due to the COVID-19 pandemic has forced many health care personnel to prolong the use of their existing equipment as much as possible. In many cases, workers cover respirators with available masks in an attempt to extend their effectiveness against the virus. Due to low mask supplies, many people instead are using face coverings improvised from common fabrics. Our goal was to determine what fabrics would be most effective in both practices. Methods and findings We examined the hydrophobicity of fabrics (silk, cotton, polyester), as measured by their resistance to the penetration of small and aerosolized water droplets, an important transmission avenue for the virus causing COVID-19. We also examined the breathability of these fabrics and their ability to maintain hydrophobicity despite undergoing repeated cleaning. Tests were done when fabrics were fashioned as an overlaying barrier and also when constructed as do-it-yourself face coverings. As a protective barrier and face covering, silk is more effective at impeding the penetration and absorption of droplets due to its greater hydrophobicity relative to other tested fabrics. Silk face coverings repelled droplets as well as masks, but unlike masks they are hydrophobic and can be readily sterilized for immediate reuse. Conclusions Silk is an effective hydrophobic barrier to droplets, more breathable than other fabrics that trap humidity, and are readily re-useable via cleaning. Therefore, silk can serve as an effective material for protecting respirators under clinical conditions and as a material for face coverings.

Addressing the global challenge of access to supplies during COVID-19

“… 95 Some others looked at using commonly available materials such as polyester, silk, nylon, etc., what their filtration and breathability is, and in one case, whether these materials could be triboelectrically charged to increase filtration. 96 , 97 Another study looked at the effect of combining different fabrics such as silk, chiffon, and cotton to create hybrid masks. They seemed to have a higher filtration than masks made with a single type of fabric, possibly in part due to the combined effect of both mechanical and electrostatic filtration.…”

“…Concerning the reuse of masks, it is far better to focus on a steady supply and reducing the need for them to be reused, and the safety and these procedures are difficult to ensure, and the financial cost of implementations can be higher than buying new disposable masks. 94 , 95 , 96 , 97 , 98 …”