Heat and moisture transfer properties of multi-layer fabrics assemblies

The purpose of the research is to study the parameters which affect heat and moisture transfer through fire fighter's clothing assemblies. The material parameters considered are thickness, thermal diffusivity, diffusion coefficient and porosity. A mathematical-computer model is developed for prediction of heat and moisture transfer properties of three-layer fabrics assemblies used in fire fighter's turnout coat. Instrumentation comprising of data acquisition hardware and software is designed to measure transient heat and moisture transfer properties of microclimates between fabric layers.;Six steady state heat stress potential values based on thermal and evaporative resistance of fabric are calculated. These resistance properties of fabric layers are measured using KES Thermolabo system.;The test materials include three outer shells, three moisture barriers and three thermal liners in 27 turnout coat assembly forms.;The theoretical model for calculating transient heat and moisture transfer properties is in very good agreement with the experimentally measured values. Low correlation is found between transient heat and moisture transfer rates and heat stress potential values defined for steady state conditions.