Analysis of Liquid Sweat Transport in Underwear Combined with Multilayer Fabric Assemblies for Firefighter Outfits

A firefighter's outfit consists of several layers with distinct properties and functions. These layers serve as barriers against external hazards but also impede the transport of sweat generated by the human body. As a result, sweat vapor often fails to transfer effectively from the body through the firefighter's protective clothing (FPC) to the environment. This can lead to sweat condensation on the firefighter's skin, causing discomfort. To enhance the physiological comfort of firefighters during firefighting and other rescue operations, it is essential to consider the transport of condensed sweat within the multilayer textile system comprising both the underwear and the FPC. In this study, 16 assembly variants were tested, combining four types of knitted fabrics for underwear with four types of multilayer textile sets designed for FPC. The liquid moisture transport properties of these assemblies were evaluated using the Moisture Management Tester (MMT290), an innovative instrument manufactured by SDL Atlas. The results demonstrated that the knitted fabrics effectively transport liquid sweat, whereas in the case of multilayer textile sets for FPC, liquid sweat transport is primarily confined to the inner layer adjacent to the skin. Furthermore, the findings indicate that by selecting an appropriate combination of knitted fabric for underwear and the inner layer of the FPC, it is possible to optimize liquid moisture transport in a firefighter's outfit.