Barrier effectiveness and thermal comfort of protective clothing materials

Abstract

To have a comprehensive understanding of protection and thermal comfort performance of a broad range of protective clothing materials, barrier and air/moisture vapor permeabilities of 36 materials commonly used for personal protective equipment were examined. Samples included nonwoven, woven, microporous membrane, and laminated fabrics. Protection performance was evaluated using three pesticide mixtures that represent a range of surface tension and viscosity. Air permeability and water vapor transmission were assessed as indications of thermal comfort performance in hot, humid environments. The overall observation of 36 materials on protection performance and air permeability showed that in general a negative relationship exists between these properties. Nonwovens covered a wide range in both air permeability and barrier performance, whereas wovens used for typical work clothing showed a narrower range. Thick, tightly woven fabrics exhibited fairly high protection performance across the pesticide mixtures and showed low air permeability. Although microporous materials exhibited relatively high barrier efficacy, less protection performance was observed against the challenge liquid of low surface tension and high viscosity. A general negative trend was observed between water vapor transmission and solid volume fraction of nonwoven and woven fabrics. Through-pore size distribution measurements indicated that pore size could play an important part in the transmission of moisture vapor, given the same solid volume fraction.