A Multifaceted Evaluation on the Penetration Resistance of Protective Clothing Fabrics against Viral Liquid Drops without Pressure

Abstract

Healthcare workers should wear appropriate personal protective clothing (PPC) on assuming the risk of exposure to various pathogens. Therefore, it is important to understand PPC performance against pathogen penetration. Currently, standard methods to evaluate and classify the penetration resistance of PPC fabrics with pressure using synthetic blood or phi-X174 phage have been established by the International Organization for Standardization (ISO). However, the penetration of viral liquid drops (VLDrop) on the PPC without pressure is also a major exposure route and more realistic, necessitating further studies. Here, we evaluated the penetration resistance against VLDrop without pressure using phi-X174 phage on woven and nonwoven fabrics of commercially available PPC classified by the ISO, and analyzed in detail the penetration behaviors of VLDrop by quantifying the phage amounts in leakthrough and migration into test fabrics. Our results showed that some nonwoven test fabrics had nearly the same penetration resistance against VLDrop, even if the ISO resistance class differed. Furthermore, the results revealed that the amount of leakage through the fabrics was correlated with the migration amount into the fabric, which was related to fluid-repellency of fabrics, suggesting the effectiveness for penetration resistance. Our study may facilitate more appropriate selection for PPC against pathogen penetration.

Germ-Free Mice Under Two-Layer Textiles Are Fully Protected From Bacteria in Sprayed Microdroplets: A Functional in vivo Test Method of Facemask/Filtration Materials

“…Toward the future, animal models could be used to further examine the role of droplet barriers in preventing the respiratory transmission of viral particles, for instance, the murine hepatitis Coronaviridae virus (39). Although we assessed combed cotton textiles of two densities, studies indicate that most textiles would be effective (21), and beneficial for the control of viral particles (40), or nanoparticles especially if cotton and electrostatic materials are used as a combination in cloth face masks (10,22).…”

“…The science of textiles is complex, and the study of textiles in particulate/air filtration using in vitro systems is becoming a reemerging field of research since the occurrence of increasingly devastating respiratory pandemics, especially COVID-19 (10,21,22,40). As a novelty, our study was designed to effectively illustrate, as a proof-of-principle, the use of our germ-free mouse housing system/model to examine the filtration potential of any type of materials in an innovative in vivo animal system.…”

Face Masks to Combat Coronavirus (COVID-19)—Processing, Roles, Requirements, Efficacy, Risk and Sustainability

“…Figure 4 a demonstrates the SEM images of spunbond-meltblown-spunbond (SMS) of a surgical face mask, while the sizes of common airborne contaminants and pathogens are shown in Figure 4 b. In a mask, non-woven SMS fabrics are typically used, which are spun-bond PP fabric (absorbent), melt-blown PP interlayer (electrically charged small fibrous material with random orientation), and spun-bond PP (blue color and hydrophobic) fabric on the outside [ 67 , 69 , 70 , 71 ]. Spunbond–meltblown–meltblown–spunbond (SMMS), spunbond–meltblown (SM), spunbond–spunbond (SS), spunbond–spunbond–spunbond (SSS), and spunbond–spunbond–meltblown–meltblown–spunbond (SSMMS) are the other most prevalent combinations of structures in various weight ranges [ 72 ].…”

Cellulose, nanocellulose, and antimicrobial materials for the manufacture of disposable face masks: A review

“…Medical face masks, also known as surgical masks or procedure masks, are usually composed of three layers of a spunbonded-meltblown-spunbonded (SMS) nonwoven fabric, where the meltblown middle layer provides higher filtration performance compared to the spunbonded layers (Ghosh 2014;Mukhopadhyay 2014). The outer spunbonded layer is typically blue and hydrophobic to prevent liquid droplets containing viral or other hazardous agents from reaching the wearer (Shimasaki et al 2020), acting as a prefilter layer for the meltblown middle layer that provides the final filtration (Mukhopadhyay 2014). The inner spunbonded layer is soft, for the wearer's comfort, and absorbent, to absorb the fluids generated by breathing, coughing, and sneezing, and it usually has no filtration function.…”