A Study on Total Heat Loss of Clothing Materials for Firefighters’ Protective Clothing

Clothing is often made of materials that impede the flow of heat and moisture from the skin to the environment. Consequently, people may suffer from heat stress or cold stress when wearing clothing in different environmental conditions. Therefore it is important to quantify the thermal resistance and evaporative resistance of clothing materials and to consider these properties when selecting materials for different clothing applications. The purpose of this study was to measure the resistance to dry heat transfer (conduction, convention, and radiation) and evaporative heat transfer provided by selected fabrics used in clothing worn by fire fighters or other rescue personnel. A comprehensive experimental work was conducted on a series of fabric samples to examine their thermal resistance, evaporative resistance, total heat loss, thermal protective performance and composite thickness. The thermal and evaporative resistance values were measured using a sweating guarded hot plate apparatus in an environmental chamber. These values were then used to determine the total heat loss that can be transferred through a fabric system in a specified environment.