Analysis on the Fire Growth Rate Index Considering of Scale Factor, Volume Fraction, and Ignition Heat Source for Polyethylene Foam Pipe Insulation

Abstract

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.

Synthesis of ZnFe2O4@Mg‐Al‐SDBS LDH composites for regulating heat and fire safety properties of polyurea

“…To be able to further evaluate the polyurea fire performance, the time to ignition (TTI), PHRR, time to PHRR (TTP), fire performance index (FPI) and fire growth index (FGI) of PUA and PUA/ZF@MASL composites are shown in Table 3. Figures 9 and 10 show the FPI (FPI = TTI/PHRR) and FGI (FGI = PHRR/TTP) of PUA and PUA/ZF@MASL composites 46 . The FPI value of pure PUA is 0.0445 m 2 /s/kW.…”

“…(FGI = PHRR/TTP) of PUA and PUA/ZF@MASL composites. 46 The FPI value of pure PUA is 0.0445 m 2 /s/kW. With the addition of ZF@MASL, the FPI values of PUA/ZF@MASL0.5, 1.0, 2.0, and 3.0 wt % are 0.0449 m 2 /s/kW, 0.0474 m 2 /s/kW, 0.066 m 2 /s/kW, and 0.0528 m 2 /s/kW, respectively.…”

Fire Growth Rate Index as a Key Fire Characteristic of Electrical Cables

“…The second reason for the problematic comparison of FIGRA values with the results of other works is the fact that these scientific papers report different methods for FIGRA determination (e.g. in study [8], FIGRA is calculated as the ratio of the maximum heat release rate to the time when this value was reached). The third reason is the already mentioned difference between the FIGRA values determined from the results of the heat release rate measured by different test methods.…”

“…These facts are the cause of the relatively large dispersion of FIGRA, e.g. from scientific papers [8][9][10] it follows that FIGRA of synthetic polymers (depending on their chemical composition, content and type of flame retardants and method of determination) can differ by up to several orders of magnitude: from tenths to tens of kW•m -2 •s -1 ). The FIGRA values can therefore only be compared if the heat release rate was determined on the same type of test equipment under identical conditions (in particular heat flux) and the same calculation method was used.…”

Recycled polyester filled with eggshells waste-based nano CaCO3: thermo-mechanical and flame-retardant features

“…As the fire growth rate decreases with lower HRR (heat release rate) and longer time taken to the ignition, it is good to decrease the HRR, which designates the content of heat released per unit time upon ignition. 71,72 Fig. 5 show the HRR, as the most important parameter that identifies the ability of a material to retard fire, of the BM-PES matrix and its ES-CaCO 3 -based nanocomposites.…”