The fire growth rate index (FIGRA), which is the ratio of the maximum value of the heat release rate (Qmax) and the time (tmax) to reach the maximum heat release rate, is a general method to evaluate a material in the fire-retardant performance in fire technology. The object of this study aims to predict FIGRA of the polyethylene foam pipe insulation in accordance with the scale factor (Sf), the volume fraction of the pipe insulation (VF) and the ignition heat source (Qig). The compartments made of fireboard have been mock-up with 1/3, 1/4, and 1/5 reduced scales of the compartment as specified in ISO 20632. The heat release rate data of the pipe insulation with the variation of Sf, VF, and Qig are measured from 33 experiments to correlate with FIGRA. Based on a critical analysis of the heat transfer phenomenon from previous research literature, the predictions of Qmax and tmax are presented. It is noticeable that the fire-retardant grade of the polyethylene foam pipe insulation could have Grade B, C, and D in accordance with the test conditions within ±15% deviation of the predicted FIGRA. In case of establishing the database of various types of insulation, the prediction models could apply to evaluate the fire-retardant performance.

This study is experimentally analyzed to extract the major parameters affecting the performance of the smoke-control system and the relations of pressure difference between vestibule and supply air pressure zone effect of supply mass flow rate and leakage area in the smoke-control zone. To obtain this, the mock-up building of three-story scale with a total of 10 compartments was constructed, and several apparatus were also installed for in-situ measurement of the ventilation flow rate, pressure difference between compartments, smoke defensive air velocity, the opening-closing force of door, etc. This article show that pressure difference in the smoke-control zone is significantly related with leakage area of vestibule in low pressure region, leakage area of supply air pressure in over pressure region and both of them in pressure control region when the pressure control range of damper is 45 Pa~55 Pa.

The present study has been conducted to analyse the effects of various pool diameters on the measurement of heat release rate (HRR) of heptane fire using large scale cone calorimeter (LSC). The burning rate which is the major parameter for HRR compared with the previous model suggested by A. Hamins. The combustion efficiency for heptane by oxygen consumption method is about 91%, which is almost same with the previous results of 92% suggested by J. Gore. The convective HRR by enthalpy consumption method was 54% lower than HRR by oxygen consumption method. This results are practical use for establishing the reliability of heat release rate for fire experiment.

In this study, we investigate the thermal characteristics of a circular fusible-type sprinkler. Analytic solutions regarding the radial-temperature distribution are obtained by using the energy-transport equation for the heat-responsive element of the sprinkler. When solving the equation, the fitted curves of the measured temperatures derived from the previous correlation of the heat-transfer coefficient are used as the boundary conditions at the element surface. To verify the accuracy of the present approach, the predictions from the use of the analytic solution are compared with the operation-time measurements of the sprinkler; the bulk temperature of the element is then estimated based on these results for the quantification of the operation time of the sprinkler. To verify the present analytic model, we systematically compare the operation time of the sprinkler with those of the response time index (RTI) and modified response time index (RTI v ) models. The results show that the present model can be used for an estimation of both the temperature distribution inside the element and the operation time of the sprinkler. ACross-sectional area per volume of the heat-responsive element (m -1 ) aThermal diffusion coefficient (m 2 /s) C p Specific heat (kJ/kg K) L Length of the heat-responsive element (m) R Radius of the heat-responsive element (m) t Time (s) t r Operation time of the sprinkler head (s) rRadial direction (m) hHeat transfer coefficient (W/m 2 K) uGas velocity (m/s)

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