Effects of moisture contents on temperature control performance of structural firefighters’ gloves with the incorporation of phase change material

Abstract

Phase change materials (PCMs) are extensively utilized in thermal management applications. We examined thermal protection enhancement in structural firefighting gloves through the incorporation of PCMs, particularly under conditions influenced by moisture from hand sweating or external water sources. We conducted experiments to assess the impact of varying moisture content (MC) levels within glove fabrics on the temperature regulation performance of PCM-integrated firefighters' gloves. Three scenarios in fire settings were considered in the study, including contact with hot surfaces (conductive heat) and exposure to hazardous environments and flashovers (radiant/convective heat sources). Our findings indicate that under intense heat, the time before reaching a second-degree burn threshold (60 °C) on hand skin surface was minimized at lower MC levels. However, when the MC level exceeded specific values, the duration of thermal protection increased with higher moisture levels. The PCM integration extended thermal protection by between 1.4 and 2.1 times during direct contact tests and by between 1.2 and 1.5 times under radiant/convective heat exposures, compared to non-PCM gloves under similar wet conditions. Additionally, PCM layer's release of latent heat during solidification led to a prolonged temperature rise on skin surface at post-exposure, while moisture assisted in enhancing the thermal dissipation rate following heat exposure due to effective water evaporation.