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In this study, two multi-layer fabric systems intended for firefighters have been tested in order to determine the basic parameters of thermal comfort. The thermal comfort is evaluated effectively by measuring the thermal properties of clothing on the sweating-guarded hotplate (skin model). The first assembly is composed of an external layer, a middle layer (thermal insulation), and an inner layer [moisture barrier - hydrophilic polyurethane (PU) membrane coated on knitted fabric]. The second one contains an external layer, a middle layer (thermal insulation), and an inner layer (liner). Both assemblies contain the same external layer and middle layer. These layers are tested as monolayers and in multi-layer clothing systems. The influence of the membrane on the thermal and water-vapour resistance of the multi-layer fabric system has been studied. When the combinations of different materials are used for a multi-layer fabric system, the thermal comfort is dependent not only on the properties of each monolayer but also on the manner in which they act together. The results show that the monolayer acting as a moisture barrier has a considerable influence on the overall watervapour transport abilities. The position of the moisture barrier in the assembly is also important in the overall value of watervapour resistance of the multi-layer system. [ABSTRACT FROM AUTHOR]

In this study, hybrid nanocomposite films were prepared by a sol-gel method. Al 2 O 3 particles of 100 nm diameter were mixed with small SiO 2 nanoparticles of 10 nm in a coating solution. After coating onto a plastic sheet, the water vapor transmittance rate (WVTR) was reduced from 12.2 to 0.15 g m −2 day −1 . However, due to the particle aggregation in the Al 2 O 3 /SiO 2 system, pore size of the barrier coating remained constant despite the Al 2 O 3 /SiO 2 ratio. To avoid particle aggregation and to reduce the WVTR, vanadium oxide was added in the coating solution to suppress the aggregation of nanofillers via dehydroxylation. From BET analysis, the addition of vanadium oxide resulted in a smaller pore size to further inhibit water vapor penetration. The WVTR was lowered to 0.095 g m −2 day −1 at a relative humidity of 100%, corresponding to an improvement of 99.2% compared to that of the pristine PET. [ABSTRACT FROM AUTHOR]

This paper describes an investigation into protective clothing for fire-fighters, made of different material combinations, based on the demand for radiant protective performance (RPP) and heat-moisture transfer properties, which are closely associated with comfort performance. The outer shell and thermal barrier were changed to measure their effects on radiant protection and comfort performance. Also, we compared clothing assemblies which incorporated moisture-permeable and moisture- impermeable barriers. It was our intention to match different material combinations of clothing assemblies, in order not only to provide effective radiant protection but also to maintain a balance between heat and moisture. This study shows the relative importance of the moisture vapour permeability of the moisture barrier on comfort performance in fire-fighters' protective clothing. [ABSTRACT FROM AUTHOR]

Building construction accounts for 40% of the global anthropogenic greenhouse gas emissions. The drastic increase in the energy costs of building materials has drawn attention to earth materials, such as rammed earth. In this study, the hygrothermal properties of rammed earth in the Tibetan Autonomous Prefecture, Sichuan Province, China were measured and compared with results from previous studies. To analyze the hygrothermal performance of a rammed earth wall, a numerical model was established and verified. The coupled heat and moisture transfer in the area of the common rammed earth wall and the moisture barrier wall was simulated with different indoor conditions, orientations, and thicknesses. The numerical results were observed to be consistent with the experimental data. In contrast to results from other studies, the earthen material analyzed in this study exhibits less vapor transfer, but better thermal stability and moisture buffering. The moisture barrier increases the average moisture content of the rammed earth wall, but reduces the maximum moisture content, thereby protecting the wall. The moisture barrier probably also reduces the moisture buffering capacity of the wall. The moisture barrier has no significant effect on heat transfer; even a west-facing wall reduces heat loss by only 3% in this area. • The studied earthen material has lower diffusivity and higher effusivity. • The moisture barrier results in a maximum reduction in moisture transfer of 35%. • The increase of moisture transfer reduces the heat loss of the wall for the whole year. • The moisture barrier will be more effective used on rammed earth wall facing west. [ABSTRACT FROM AUTHOR]