Heat Transfer Model of Flame Resistant Fabrics During Cooling After Exposure to Fire

Protective clothing is used in many industries to protect firefighters and other workers from fire and other hazards. While skin burns can occur during a fire, protective fabric temperatures remain high for some time even after a fire ends. Therefore, skin burn injuries can occur during the time in which a fabric is cooling. A heat transfer model has been developed that can predict inherently flame resistant fabric temperatures and skin burn injuries during this cooling phase. This paper describes the heat transfer model, including methods used to calculate the apparent heat capacity and the convection heat transfer coefficient as the fabric cools. The new model has been validated using data from bench top tests of Kevlar®/PBI fabric specimens. Parametric studies using the model demonstrate the importance of selected thermal properties and boundary conditions on fabric temperatures and bench top test results.