Measuring of Equivalent Air Layer Thickness of Nanofibre Textiles

This article deals with selecting the appropriate method of measurement water vapour diffusion through nanofibre textiles. Parameter for comparison of different sheet materials for its ability to brake the water vapour is a equivalent air layer thickness value Sd. The equivalent air layer thickness Sd [m] expresses the equivalent air layer thickness of the air layer, which would have the same diffusion resistance as the thickness of the measured material. It is necessary to choose the appropriate measurement method for determining the value Sd with diffusion open materials such as nanofibre materials. This article compares the outcomes of two measurement methods – Dry Cup Method and Tube Method. The measurements were carried out on a sample from nanofibre textiles based on PVDF.