Personal protective clothing and safety of firefighters near a high intensity fire front

The main objective of this work is the establishment of useful guide lines for secure fighting of high intensity fires, namely the determination of the influence of the personal protective clothing properties on safety during wildland firefighting operations. The physiological reaction of men exposed to these extreme conditions is obtained by numerical simulation of the heat and the mass transfer from an individual in the proximity of a fire line, as representative of a typical situation of a firefighter suppressing a high intensity fire. It is obvious that the impinging flux density depends on flame's dimensions and its properties as well as on the distance between the flame and those involved in fire suppression activities. The results obtained were calculated using a computer program based on a modified version of the Stolwijk thermoregulation model. Taking into account the time evolutions of skin, rectal and hypothalamus temperatures, a parametric study is presented about the importance of clothing properties, activity level and other external parameters in order to avoid the risk of significant undesired thermophysiological reactions within the firefighters. The results clearly show that, besides the improvement of personal protective clothing properties, the safety of firefighters is essentially related to good control of the exposure times to these high intensity radiation fluxes.