Characterisation of pyrolysis and combustion parameters of charring materials most frequently found in buildings

A comprehensive study has been conducted on some charring materials frequently found in buildings to characterise pyrolysis and combustion parameters concerning the variations in heating rate, temperature and heat flux. Since these parameters are input for computational fluid dynamics (CFD)-based fire models, incorporation of the effects of heating rate and heat flux when simulating building fires may lead to better predictions of tenability conditions. Three common construction and building materials were selected, namely pine, cotton and wool, to characterise via experimental protocols which can serve as examples of future novel charring materials. Parameter values related to pyrolysis reactions were determined using thermogravimetric analysis and differential scanning calorimetry. The values of the combustion parameters were obtained using cone calorimetry. It was found that the variation in heating rate has a significant effect on the values of the pyrolysis parameters of the studied materials. The kinetic parameter and heat of reaction (HoR) values of pine increased with the increment in heating rate. Conversely, the kinetic parameter values of cotton and wool decreased as the heating rate increased, whereas the HoR values followed a similar incremental trend with the increasing heating rate. The variation in combustion parameter values varied concerning heat flux due to the presence of high moisture contents and possible variations in char development in all materials. As CFD-based fire models are currently widely used to design and assess performance-based building fire safety designs, to obtain better predictions of tenability conditions, a proposal for the optimised use of parameters is presented.