Efficacy of face masks in preventing inhalation of airborne contaminants

Surgical mask filter and fit performance

“…Two studies simulating inward leakage compared surgical masks sealed and unsealed on a mannequin face and found fit factors from 3 to 5 (18% to 32% face-piece leakage) for 1.8-mm dioctyl phthalate particles and 22-mm fungal spores. 15,25 A significantly higher prevalence of antibodies for several respiratory tract viruses (influenza A and B and respiratory syncytial virus) was found in 50 dental surgeons compared with 50 controls. However, no significant difference in antibody prevalence was found between surgeons wearing masks versus those who occasionally or never wore surgical masks.…”

Issues Affecting Respirator Selection for Workers Exposed to Infectious Aerosols: Emphasis on Healthcare Settings

“…Subsequent studies, in which not only surgical masks made of gauze and muslin but also ones made of paper, foam, and synthetic materials were evaluated, resulted in filter efficiencies ranging from the teens to nearly 100% (Brosseau, McCullough, & Vesley, 1997;Ford & Peterson, 1963;Ford, Peterson, & Mitchell, 1967;Miller, 1973Miller, , 1995Rogers, 1980). The findings of other studies in which surgical masks were evaluated (with some reported to have highly efficient filters) have emphasized that a secure face seal is essential for preventing infectious particles from escaping (as well as entering) at a mask's edges (Ha'eri & Wiley, 1980;Johnson, Martin, & Resnick, 1994;Pippin, Verderame, & Weber, 1987;Tuomi, 1985). Researchers, who have studied the aerosols and spatters produced during some dental procedures and the blood aerosols and spatters generated during surgeries, defined the size of spatter droplets to be 50 m and larger (Heinsohn & Jewett, 1993;Miller, 1973).…”

Characterization of Aerosols Produced during Surgical Procedures in Hospitals

“…This is particularly true for human HBV (Petersen, 1980) and papillomavirus (Garden et al, 1988;Ferenczy et al, 1990;Lobaico et al, 1989;Sawchuk et al, 1989;Abramson et al, 1990), and has been reported to occur in rabies (Giachino et al, 1988). Unfortunately, surgical masks do not effectively protect HCWs from inhaling inhalable aerosols due to the lowto-moderate filtration efficiency and potential face seal-leaks of the masks (Pippin et al, 1987;Reingold et al, 1988;Jewett, 1990).…”