Thermal Liner Construction and Insulation Materials
topic
Thermal liner assemblies use flame-resistant nonwoven batting layers of meta-aramid or oxidised polyacrylonitrile fibres at weights of 80 to 200 grams per square metre quilted between flame-resistant face and back fabrics, providing the majority of total composite thermal insulation through the entrapped air within the fibre structure, with higher loft and batting weight increasing thermal resistance and TPP value while increasing bulk, stiffness, and physiological heat burden.
Role
Provides the primary thermal insulation in the firefighting clothing composite system, with thermal liner design being the principal variable controlling the TPP performance level above the minimum provided by the outer shell, and the balance between batting weight and insulation value versus garment bulk, weight, and heat stress burden being the central design optimisation for thermal liner systems across the performance range from minimum EN 469 compliance to maximum available protection.