RESUMO
The protective properties of nonwoven materials (Spandbond, SMS) used to manufacture 3-5-layer medical masks, by using model physical and bacterial test aerosols, were experimentally assessed. It was shown that the more layers of the materials, the less permeable they became for test aerosols. Three-five-layer masks made from SMS at a density of 42 g/m2 were found to have higher protective properties for oil mist and fine aerosol than those made from Spandbond at a density of 25 g/m2. Five-layer SMS materials at a density of 42 g/m2 have the highest values of bacterial aerosol retention.
Assuntos
Máscaras/normas , Medicina do Trabalho/métodos , Polipropilenos , Dispositivos de Proteção Respiratória/microbiologia , Dispositivos de Proteção Respiratória/normas , Doenças Respiratórias/prevenção & controle , Desenho de Equipamento , Filtração , Humanos , Controle de Infecções , Medicina do Trabalho/instrumentação , Serratia marcescens/isolamento & purificaçãoRESUMO
The permeability of varying density felts (Spandbond, SMS, Tyvek, Sontara) for throw-away medical overalls was experimentally assessed under statistic and dynamic conditions, by using model test aerosols, including bacterial one. Their permeability was shown to decrease with the higher density of the materials under study. Laminated Span-bond contributes to an abrupt reduce in the bacterial penetration of this kind of tissues and enhances their protective properties. The felts CMC, Tyvek, Sontara, and laminated Spanbond were found to have the highest protective properties. In terms of their barrier and protective properties, the felts surpass the tissues used to make re-usable protective medical overalls.
