Room Corner Test Research Articles

Fire characteristics of cored composite materials for marine use

Abstract This paper presents results from Cone Calorimeter testing of two types of cored composite materials used in shipbuilding: a GRP/Balsa-cored sandwich and a GRP/PVC foam-cored sandwich. The observed phenomena of delamination, melting and charring of the core materials, and edge effects are discussed in the context of how they affect test results. The “standard” ignition data analysis method specified in ASTM E 1321 and Janssens’ “improved” method of analysis were both used to derive effective material ignition properties such as ignition temperature and kρc. The findings of the study indicate that Janssens’ method is well suited for analyzing the ignition data of cored composite materials. Derived material properties are used as input to Quintiere’s fire growth model in order to evaluate their influence on time to flashover predictions in the ISO 9705 Room–Corner test scenario.

Ignitor and Thickness Effects on Upward Flame Spread

The effects of a material's ignitor characteristics and burning duration on upward wall flame spread are investigated. The ignitor is represented as an energy line source. Its energy release rate and its duration after ignition are considered. The material is represented as a finite, thick noncharring material with properties representative of polymethylmethracrylate (PMMA). A Volterra integral equation is solved for upward flame speed by numerical methods, and a transient, noncharring burning rate model is included. Results show the influence on propagation of ignitor effects and material thickness. A propagation map is computed showing the domains of flames that spread and flames that stop. Criteria for propagation and how propagation affects fire growth are considered in a standard room-corner test.

Models for calculating flame spread on wall lining materials and the resulting heat release rate in a room

An extensive research programme, dealing with fire growth on combustible wall lining materials, has been ongoing in Sweden over the last decade. Several lining materials were tested in bench-scale fire tests in order to derive basic material flammability parameters. The same materials were also tested in a full scale room test and a 1 3 scale room test for two different scenarios, A and B. Scenario A refers to the case where walls and ceiling are covered by the lining material, Scenario B where lining materials are mounted on walls only. This study utilises the results from these experiments and presents a mathematical model where material properties derived from standardised bench-scale tests are used as input data. The model predicts fire growth in the full- or 1 3 scale tests, in two different scenarios (A and B), and consists of sub-models for calculating the rate of heat release, gas temperatures, radiation to walls, wall surface temperatures and flame spread on the wall lining material. A thermal theory of wind-aided flame spread on thick solids is examined and solutions are given and analysed for flame spread velocities under ceilings. Both numerical and analytical solutions are discussed. The analytical solutions can be used to evaluate the flame spread propensity of materials and thus, whether a certain material is likely to go to flashover or not in the Room Corner Test. More generally, the solutions can be used to estimate whether a material will spread flame in a variety of concurrent flow flame spread scenarios. Results from the analytical solutions are compared with experimental flashover data for 22 materials, showing a good agreement. The numerical solutions are incorporated into a simple room fire model. The results from the numerical model are compared with experiments on 22 materials tested in the full scale room for Scenario A. Comparisons for Scenario B are made with 10 materials tested in the 1 3 scale room. The results show reasonably good agreement for most materials between the model and the experiments.

Assessment Of Smoke Production From Building Products

By use of test data from the Cone Calorimeter bench scale test and two full scale fire tests (IS0 Room Comer Test and CSTB Room Fire Test), relationships between smoke test data for the two scales were investigated. The study was based on test results for 38 products. Bench scale and full scale smoke production were normalized to either area burnt, mass loss or heat release and then compared. The most interesting parameter was smoke production per heat release, and for the products tested in the CSTB Room Fire Test there was found good correlation and a correlation coefficient of 0.99. It was shown that smoke production in full scale was only about 45-60% of what was found in bench scale, and this is probably due to secondary combustion which occurs in the hot smoke layer. Before a secondary combustion occurs, the room fire is ventilation controlled and can produce more smoke than is found in bench scale. Thus the full scale fire influences smoke production in a way that may hinder relationship between bench scale and full scale smoke parameters. Full scale smoke test data from the IS0 Room Corner Test were difficult to calculate, due to problems with finding the net heat release from the burnt products and the estimated burnt area. A one-to-one relationship between bench scale and full scale for the average effective heat of combustion (hhWg) was found and the plot obtained a correlation coefficient of 0.99. Since direct mass loss measurements are not done in these full scale tests the smoke extinction area (SEA) is actually identical to smoke produced per heat release (TSP/THR).

Smoke data from the Cone Calorimeter for comparison with the room fire test

AbstractSmoke production in the full–scale room fire test ISO 9705 (Commonly referred to as the Room Corner Test) and in the Cone Calorimeter ISO 5660 has been analysed for three sets of building products comprising a total of 28 products. The smoke production may be critical for the fire classification of surface products since some products produce large amounts of smoke in the room fire test even if they do not reach flashover within 20 min. Several smoke parameters in the Cone Calorimeter and the room fire test have been analysed. Good correlations have been obtained when the products are divided into two groups: products with more than 10 min to flashover in the room fire test and those with less than 10 min. These two time categories correspond to the two heat output levels in the room fire test: 100 kW for the first 10 min and then 300 kW up to 20 min. For products with more than 10 min to flashover the average rate of smoke production and the total smoke production seem to be useful parameters for predictions of smoke release in the room fire test. Both parameters have good correlations between data from the Cone Calorimeter and the room fire test. For products with less than 10 min to flashover no parameter seems to give useful predictions. For all products evaluated together, the correlations are not so good, but the same regression lines as for products with more than 10 min might be used as a first rough estimate. In this case the total smoke production in the Cone Calorimeter could be used to estimate the total smoke production in the room fire test for different building products, independent of their estimated time to flashover.It is suggested that the average rate of smoke production and the total smoke production from the Cone Calorimeter is reported in addition to the mass‐based specific extinction area. This will be helpful in predicting smoke release in the room fire test and will also make the data on smoke release analogous to those on heat release.

A mathematical model for calculating heat release rate in the room corner test

A mathematical model is presented for calculating the heat release rate in the room corner test, where lining materials are mounted on both walls and ceiling. The model is based on a thermal theory for concurrent flow flame spread. By using a simple mathematical representation of the heat release rate from the cone calorimeter, analytical solutions are arrived at for the velocity and position of the pyrolysis front in the room corner test as well for as the heat release rate from the burning material. Results from calculations are compared with those from experiments, showing good agreement for 11 materials out of 12.

A simulation model for fire growth on materials subject to a room-corner test

A mathematical model has been developed to simulate fire growth on wall and ceiling materials when subject to a room-corner fire test exposure. The model predicts the area of burning, the upper layer gas temperature, and the rate of energy release as a function of time. Material fire property data are developed from apparatuses described in ASTM E 1321 and E 1354. The results compare favorably to experimental data generated in Sweden for 13 materials tested. Furthermore, the model shows the sensitivity to ‘flashover’ for thin materials relative to small variations in their property data.