The electrical circuit for the recently developed transient plane source (TPS) technique for fast and precise measurements of thermal tramport properties of solids has been modified for more convenient 8nd more automated measurements. The technique has been tested for measurements of thermal conductivity and thermal diffusivity for a series of building materials ranging from thermally insulating materials (extruded polystyrene and PMMA) to good thermal conductors (stainless steel and aluminium). The results obtained in this work agree well with other techniques and international standrrrd materials This agreement indicates that the TPS method is accurate to within f 5% over a thermal conductivity range of four orders of magnitude (0.02 W m K to 2QO W m K I).

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Abstract. Parameters leading to the severity of the fire in Laerdalsøyri, Norway, January 18th to 19th 2014, have been analyzed. The fire in the first villa developed significantly faster than the fire fighters could handle and the fire quickly spread to other structures. In addition to 36 modern buildings, 4 historic buildings in Gamle Laerdalsøyri cultural heritage area were lost. Heroic effort of local and neighbor community fire brigades, police, military forces and volunteers prevented the fire from destroying the whole village, including the remaining 157 historic buildings. Adiabatically heated (low humidity) air from surrounding high mountains gave outdoor wood fuel moisture content (FMC) of about 7.6%. Inside inhabited buildings, it is shown that the wooden products reached about 4.5% FMC prior to the blaze. When ignited, this resulted in rapid fire development. Two story villas burned down in less than 1 h while producing much embers and firebrands. Strong shifting winds subsequently spread the fire to neighbor houses by flame contact (periodically 20 m long horizontal flames) and over long distances (200 m) by embers and firebrands. Based on the present work, an increased fire risk associated with low FMC in inhabited wooden houses during winter time can be predicted. This is of value when considering measures to reduce the probability of a fire outbreak as well as measures mitigating the escalation of a potential fire.

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It has recently been demonstrated that 50 mm thick industrial grade thermal insulation may serve as passive fire protection of jet fire exposed thick walled steel distillation columns. The present study investigates the performance of thermal insulation in conjunction to 3 mm, 6 mm, 12 mm and 16 mm steel walls, i.e., where the wall represents less heat sink, when exposed to 350 kW/m2 heat load. Regardless of the tested steel plate thicknesses, about 10 min passed before a nearly linear steel temperature increase versus time was observed. Thereafter, the thinnest plates systematically showed a faster temperature increase than the thickest plates confirming the wall heat sink effect. To study thermal insulation sintering, 50 mm thermal insulation cubes were heat treated (30 min holding time) at temperatures up to 1100 °C. No clear sign of melting was observed, but sintering resulted in 25% shrinkage at 1100 °C. Thermogravimetric analysis to 1300 °C revealed mass loss peaks due to anti-dusting material at 250 °C and Bakelite binder at 460 °C. No significant mass change occurred above 1000 °C. Differential scanning calorimetry to 1300 °C revealed endothermic processes related to the anti-dusting material and Bakelite mass losses, as well as a conspicuous endothermic peak at 1220 °C. This peak is most likely due to melting. The endothermic processes involved when heating the thermal insulation may to a large part explain the 10 min delay in steel plate temperature increase during fire testing. Overall, the tested thermal insulation performed surprisingly well also for protecting the thin steel plates.