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Showing papers in "Fire and Materials in 1996"


Journal ArticleDOI
TL;DR: In this article, the authors compared five new intumescent additive mixtures and a carbonizing additive system with additive formulations previously developed in laboratory in terms of fire retardancy of polypropylene-based formulations.
Abstract: The study compares five new intumescent additive mixtures and a carbonizing additive system with the ammonium polyphosphate–pentaerythritol system and additive formulations previously developed in laboratory in terms of fire retardancy of polypropylene-based formulations. The mixture of diammonium pyrophosphate and polyols produced by agrochemical industry xylitol and d-sorbitol (carbonization agent) are FR additive mixtures of interest for polyolefins. Moreover, the FR performance of the mixture of ammonium polyphosphate and polyamide-6 is reported. It is proposed that boric acid salts have to be developed as precursors for carbonization catalytic species. A thermal analysis study shows that FR performances and amounts of carbonaceous materials resulting from the thermal degradation of the additive mixtures are not related. An additional compilation of previous spectroscopic studies by the laboratory confirms that the intumescent process results from the formation of polyaromatic species and that FR systems maintain acidic species in a relatively high temperature range. An ESR study discusses the presence of π radicals in the protective coating formed using the additive systems. It provides information on the size of the carbonaceous structures in the materials and the presence of crystalline phases in the coating. Finally, the participation of free radicals in the formation of chemical bonds between the materials produced from the additives and the products of the degradation of the polymer is discussed.

159 citations


Journal ArticleDOI
TL;DR: In this paper, the authors present an experimental investigation conducted to determine the pulsating characteristics of buoyant diffusion flames and confirm the hydrodynamic nature of flame puffing: interplay of buoyancy and fluid motion.
Abstract: This paper reviews the past research, experimental techniques and scaling relationships used in the studies of oscillatory buoyant diffusion flames and reports an experimental investigation conducted to determine the pulsating characteristics of such flames. The experimental data were obtained by using three techniques, namely, pressure fluctuation measurements, thermal imaging and high-speed video photography. Present findings are compared with data sets reported in the literature and correlations for pulsation frequency suggested by previous studies are independently verified. Analysis of the experimental data on frequency of pulsations in different burners shows that for a fixed-diameter flame the pulsation frequency is almost independent of fuel flow rate. The equation f=1.68D-0.5 gives the best approximation for the relationship between pulsating frequency and diameter over a wide range of data. An alternative way of expressing the relationship between the key variables is St=0.52*(1/Fr)0.505. This proves to be a better way of expressing the relationship since it can include the effect of the fuel flow rate. Slight modifications to this expression allows prediction of flame oscillations under elevated/reduced gravity and isothermal buoyant plumes. This relationship and the observations of the present study confirm the hydrodynamic nature of flame puffing: interplay of buoyancy and fluid motion.

99 citations


Journal ArticleDOI
TL;DR: In this article, the performance of load-bearing light steel-frame systems exposed to fire is investigated, and methods are presented for calculating the reduction of steel strength and stiffness at elevated temperatures, and for predicting the deflections resulting from temperature gradients and P-Δ effects.
Abstract: Light steel-frame building systems are becoming more prevalent in commercial, industrial and residential construction in New Zealand. Tested fire resistance ratings are generally available for non-load-bearing systems, but not for load-bearing applications. This study investigates the performance of load-bearing light steel-frame systems exposed to fire. Methods are presented for calculating the reduction of steel strength and stiffness at elevated temperatures, and for predicting the deflections resulting from temperature gradients and P-Δ effects. Heat transfer modelling by computer is used to predict steel framing temperatures for systems exposed to the standard ISO 834 time–temperature curve and real fires. Three full-scale furnace tests were carried out to evaluate analytical predictions. A design procedure is proposed.

83 citations


Journal ArticleDOI
TL;DR: In this article, the influence of physicochemical properties of zeolites is discussed and it is shown that zeolite may act as a catalyst for the development of the intumescent carbonaceous material and stabilize the carbonaceous residue resulting in the degradation of the Intumescent shield Characterized by MAS-NMR 27 Al and 29 Si, it is proposed that alumino and silicophosphate species formed are catalysts active for the synthesis of a protective carbon-based material.
Abstract: The adduct of zeolites in intumescent formulations of thermoplastic polymers (additive ammonium polyphate and pentaerythritol) leads to a great improvement in their fire retardant performance. A classification of different groups (A, X, Y, Mordenite and ZSM-5) is presented. The influence of the physicochemical properties of the zeolites is discussed. Thermogravimetric (TG) analyses reveal that the zeolite may act as a catalyst for the development of the intumescent carbonaceous material and stabilize the carbonaceous residue resulting in the degradation of the intumescent shield Characterized by MAS-NMR 27 Al and 29 Si, it is proposed that alumino- and silicophosphate species formed are catalysts active for the synthesis of a protective carbon-based material.

74 citations


Journal ArticleDOI
TL;DR: In this article, the authors review the findings of microgravity-combustion research that are relevant to techniques of spacecraft fire safety and further illustrate the practical applications of some fire-safety requirements and design features of the Shuttle and those in progress for the International Space Station.
Abstract: Fire prevention, detection, and suppression requirements for spacecraft are based on those established for terrestrial and aircraft systems. In the weightless (or microgravity) environment of an orbiting spacecraft, however, the buoyant upward flow typical of fires in terrestrial environments is nearly absent; and this feature profoundly influences fire characteristics and responsive safety strategies. This paper reviews the findings of microgravity-combustion research that are relevant to techniques of spacecraft fire safety. These practical applications are further illustrated by descriptions of some fire-safety requirements and design features of the Shuttle and those in progress for the International Space Station.

59 citations


Journal ArticleDOI
TL;DR: Partial substitution of ammonium polyphosphate (APP) by manganese dioxide (MnO 2 ) in polyamide 6 (PA-6) fire retarded with 20% of APP strongly increases the fire retardant effect as discussed by the authors.
Abstract: Partial substitution of ammonium polyphosphate (APP) by manganese dioxide (MnO 2 ) in polyamide 6 (PA-6) fire retarded with 20% of APP strongly increases the fire retardant effect. 'Linear pyrolysis' experiments, which are modified cone calorimeter tests, show an increase in the amount and an improvement of the shielding properties of the intumescent char formed on the surface of burning polymer. The enhancement of the yield of aliphatic-aromatic char stable to oxidation was observed in thermogravimetry under air. The fire retardant action of an APP/MnO 2 mixture in PA-6 is twofold. On the one hand, this additive promotes involvement of the polymer in the charring and, on the other, the formed manganese phosphate glasses improve the thermo-insulating properties of the intumescent char on the surface of burning PA-6.

58 citations


Journal ArticleDOI
TL;DR: In this article, the reduction of embedding strength and the temperature were investigated, and the results of the calculations also showed that there is a considerable reduction of the embeddings strength during the first period of fire.
Abstract: Nailed joints with wood members were exposed simultaneously to standard fire and constant load. Different loads were applied in the range of 0.1 to 0.6 of the estimated failure load at normal temperature. Measurements of the rate of charring and the temperature were used to determine the temperature profiles and further to estimate the reduction in the strength properties. The test results are compared with calculations based on the theory of K. W. Johansen. Three different relations between the reduction of embedding strength and the temperature were investigated. For one of these relations, the theory agrees well with the results obtained in the fire tests. The results of the calculations also show that there is a considerable reduction of the embedding strength during the first period of fire.

47 citations


Journal ArticleDOI
TL;DR: In this paper, the results of the evaluation tests (LOI and UL 94) are affected in different ways by the adduct of the different clay material and that an increase in the LOI is not necessarily related to an increase of the UL 94 classification.
Abstract: Addition of natural clay materials in intumescent polypropylene-based formulations (additive: ammonium polyphosphate and pentaerythritol) leads either to a decrease or to an increase of their fire retardant performances versus the chemical or the physical characteristics of the clay materials. A study of the factors affecting these performances has been carried out using linear and principal components analysis. This analysis shows that the results of the evaluation tests (LOI and UL 94) are affected in different ways by the adduct of the different clay material and that an increase in the LOI is not necessarily related to an increase in the UL 94 classification. LOI values are improved by the presence of the montmorillonite and of illite clay minerals which may react with acidic phosphate to form active carbonization catelysts, in addition, the results of the LOI test are improved by the presence of quartz and other foreign minerals in the clay materials. This study discusses the part played by the different constitutive minerals in the formation of defects in the polymer chain during the mixing process. It is proposed that the presence of these defects leads to a change in fire retardant performance.

41 citations


Journal ArticleDOI
TL;DR: In this article, an estimate of the annual generation of polychlorodibenzodioxins and furans in the United States as a result of PVC burning in house fires is made using building data and fire loss statistics and soot and ash samples obtained from laboratory experiments and building fires involving PVC.
Abstract: An estimate of the annual generation of polychlorodibenzodioxins and furans (PCDD/F) in the United States as a result of PVC burning in house fires is made using building data and fire loss statistics and soot and ash samples obtained from laboratory experiments and building fires involving PVC. Using conservative estimates for construction, fire involvement and formation, dioxin generation from PVC in house fires is estimated to be in the range of 0.074 to 8.6 g TEQ yr -1 as soot, 0.4 to 14 g TEQ yr -1 as ash, and thus 0.47 to 23 g TEQ yr -1 total. The maximum likelihood estimate is approximately 0.3g TEQ yr -1 as soot and 1g TEQ yr -1 as ash. Any of these estimates constitutes a minuscule fraction of the 9300 g annual air emissions or the 20 000 - 50 000g (TEQ) annual deposition from the air estimated by EPA.

27 citations


Journal ArticleDOI
TL;DR: In this paper, the results of an extensive study of the mechanical physical, electrical and fire properties of polymeric materials, both halogenated and non-halogenated, intended for cable applications were presented.
Abstract: This paper, the first of a series of three, describes the results of an extensive study of the mechanical physical, electrical and fire properties of polymeric materials, both halogenated and non-halogenated, intended for cable applications. The objective of this study was to provide, by means of generally recognized standard tests, data, which should make possible a dispassionate fire hazard analysis of the relative merits of materials. Excellent materials were found with different chemical compositions. The results indicate the following: (1) Materials can be suitable for wire and cable applications irrespective of their chemical composition. (2) Halogen-containing materials, as a group, tend to outperform non-halogen materials in terms of the major fire properties: •Heat release •Ignitability •Flammability (3)Most commercial materials tend to have adequate mechanical and physical properties, but halogenated materials are, as a rule, slightly more satisfactory. (4)Compared to fire retarded non-halogenated materials, halogen-containing materials tend to have better performance in terms of some of the more important electrical properties, particularly dielectric breakdown voltage. (5)The resistance to ageing of non-halogenated materials is somewhat suspect, particularly with respect to attack by oils. (6)The smoke obscuration per unit mass of non-halogenated (polyolefin-based) materials is superior to that of vinyl-based materials, but differences are significantly reduced when considering the expected smoke obscuration in actual full-scale fires, due to the overall lower tendency of halogenated materials to burn; the smoke obscuration resulting from fluorinated materials is also low. (7)Smoke corrosivity is the single property where non-halogenated materials clearly outperform halogenated materials.

26 citations


Journal ArticleDOI
TL;DR: In this article, a total of 21 electrical cables were made, all with essentially identical construction but differing in the chemical composition of sheath and/or insulation, which were all commercially available materials, both halogenated and non-halogenated.
Abstract: A total of 21 electrical cables were made, all with essentially identical construction but differing in the chemical composition of sheath and/or insulation, which were all commercially available materials, both halogenated and non-halogenated. All cables were tested in two large-scale cable tray tests, ASTM D5424 (CSA FT-4 protocol), with a total length of 2.44 m and IEC 332-3, with a total length of 3.5 m. The cables were also tested in a number of small- and medium-scale tests for flame spread (IEC 695-2-2, IEC 332-1, UL 1581 Part VW1, BS 476 Part 12E, DIN 4102 Part 16), temperature increase (DIN 4102 Part 16) and smoke obscuration (IEC 1034-2, BS 476 Part 12E). Finally, all cables were tested in the cone calorimeter (ISO 5660), horizontally, at incident fluxes of 20, 40 and 70 kW m−2. All the cables passed the mild flammability tests, but distinctions could be made based on the afterflame time observed, where halogenated cables outperformed non-halogenated cables by a significant margin. It was also possible to distinguish between the halogenated and non-halogenated cables on the basis of the cable length charred in some tests. In terms of smoke obscuration, it was found that the rankings offered by the various tests were very different. While non-halogenated cables had improved smoke performance over traditional vinyl types, fluorinated cables performed very well. This confirms the importance of material selection by performance rather than by chemical composition. Almost all cables performed sufficiently well that they generated relatively limited amounts of smoke under realistic end-use fire test conditions. The peak heat release rate in the large-scale cable tray test (ASTM D5424) served as an excellent criterion for discriminating between the fire performance of the various cables (the traditional criterion being char length). The average rate of heat released also served to distinguish between different levels of cable fire performance. Moreover, cables passing the test tended to release less heat and smoke than those that failed. The trends observed in the cone calorimeter heat release test were similar to those in the large-scale test and show good correlation between cable tray char length and cone calorimeter heat release. It was observed that the halogenated cables tested performed better than the non-halogenated cables in terms of heat release rate by factors ranging from two to greater than five. The results indicate that cables with excellent fire performance can be constructed by using a variety of materials. It is thus important to specify fire performance and leave material choice to manufacturers.

Journal ArticleDOI
TL;DR: In this paper, a 1 m x 1 m water cooled vertical flat plate calorimeter located 0.8 m above and inside a 6 m x 6 m JP-4 pool fire is described.
Abstract: Quasi-steady-state heat fluxes absorbed on the calorimeter surface in ten vertical 0.1 m high x 1 m wide zones were measured by means of water calorimetry. The calorimeter surface also included an array of intrinsic thermocouples to measure surface temperatures, and an array of Schmidt-Boelter radiometers for a second, more responsive, method of heat flux measurement. The pool fire environment characterization was done with measurements from velocity probes, directional flame thermometers (DFTs), and thermocouples. The initial measurements with a 1 m x 1 m water cooled vertical flat plate calorimeter located 0.8 m above and inside a 6 m x 6 m JP-4 pool fire are described. Water calorimetry measured absorbed surface heat fluxes of about 65-70 kW m -2 with a gradual decrease with increasing height above the pool. Intrinsic thermocouple measurements recorded typical calorimeter surface temperatures of about 500°C, with spatial variations of ±150°C. Gas velocities across the calorimeter face averaged 3.4 m s -1 with a predominant upward component, but with an off-vertical skew. Analysis of data collected in the fire environment in the vicinity of the calorimeter was performed to characterize the fire environment and to determine the input parameters required to calibrate analytical models. For this test, the emissive power distribution near the plate was essentially linear. Flux measurement in the fire environment ranged from 75 kW m -2 to 175 kW m -2 . With temperature and heat flux data, effective absorption coefficients were determined by using a two-flux method to solve the inverse problem. The results show that the optical thickness, increases with increasing distance from the calorimeter surface. The effective absorption coefficient is approximately 0.8 m -1 in the vicinity (0-1.85 m) of the calorimeter and is approximately 2 m -1 in the vicinity (1.85-2.8 m) of the plume centerline The observed decrease in heat flux on the calorimeter surface with increasing vertical height is consistent with analytical fire models derived for constant temperature surfaces. Results from several diagnostics also indicated trends and provided additional insight into events that occurred during the fire. Some events are correlated, and possible explanations are discussed.

Journal ArticleDOI
TL;DR: In this article, an overview is given of several methods for quantitative analysis of FTIR spectra, each method has its particular advantages and disadvantages, depending on the gas component to be analysed in smoke gas spectra.
Abstract: In this paper an overview is given of several methods for quantitative analysis of FTIR spectra. Each method has its particular advantages and disadvantages. Therefore, depending on the gas component to be analysed in smoke gas spectra, an optimal choice of method has to be made. This choice depends on several different aspects: 0 Is the spectral band of interest free of interfering components? 0 Does the absorptiowoncentration relation show strong deviations from Beer’s law? 0 Are significant baseline corrections necessary? 0 Does the applied model need to warn for the presence of unexpected components? 0 Is it sufficient to use only a few wavenumbers or is a full-spectrum method necessary? It will not be easy to make the appropriate choice. However, in some cases, statistics can help, in others, a good rule of thumb is to keep the choice as simple as possible. 01% by John Wiley & Sons, Ltd.

Journal ArticleDOI
TL;DR: In this article, a number of common tropical timbers have been subjected to thermal analytical investigation as part of a wider research programme under air atmospheric conditions Thermal parameters obtained were correlated with oven-dry densities of the timbers.
Abstract: A number of common tropical timbers have been subjected to thermal analytical investigation as part of a wider research programme under air atmospheric conditions Thermal parameters obtained were correlated with oven-dry densities of the timbers. Two well-defined pyrolysis stages have been observed which occur over the temperature ranges 201-426°C and 397-557°C. The kinetics of the thermal degradation of the timbers were obtained using Broido's analytical procedure. These results were interpreted on the basis of the known mechanism of pyrolysis and the calculated kinetic parameters were discussed within the context of other published values for cellulose.

Journal ArticleDOI
TL;DR: In this paper, the minimum ignition temperature of a cloud of polyethylene, an organic dust, was determined using the Godbert-Greenwald furnace apparatus for different particle sizes and dust concentrations.
Abstract: Dust explosion hazard exists in plants and facilities wherever combustible dusts are handled. The minimum ignition temperature of dust clouds is an important factor requiring special attention for the design of any explosion preventive measures. The present paper is confined to a study of the minimum ignition temperature of the cloud of polyethylene, an organic dust. This parameter was determined using the Godbert-Greenwald furnace apparatus for different particle sizes and dust concentrations. Some preliminary experiments were carried out for determination of minimum explosive concentrations of polyethylene dust to specify experimental conditions for determination of minimum ignition temperature. The experimental results, particularly variation of minimum ignition temperature with particle size and dust concentration, have been explained on the basis of a two-stage ignition involving devolatilization of solid particles into gaseous intermediates and homogeneous combustion of these gaseous components. A model was also developed for determining the minimum ignition temperature of polyethylene dust simulating conditions in the test furnace and this will be presented in a separate paper.

Journal ArticleDOI
TL;DR: Based on the CFAST model, a two-layer zone model developed to predict the environment in a multi-compartment structure subjected to a fire is described in this article, where the predictive equations, fire sub-processes and algorithm are concisely described.
Abstract: Based on the CFAST model, this paper describes a two-layer zone model developed to predict the environment in a multi-compartment structure subjected to a fire. The predictive equations, fire sub-processes and algorithm are concisely described. In order to validate the model and program a series of experimental data obtained from Cooper's work at NIST were selected for comparison with numerical results, and the comparison is fundamentally favourable. This paper presents an example of this comparison, including the results simulated by the CFAST zone model (Version 1.6). It is shown from the comparison that this model predicts better results than that of the CFAST for these cases, and convection heat transfer may be underestimated in the two models. It is also shown that C.W. Gear's stiffly stable method is feasible in numerically integrating the governing equation set. Additionally, this model is applied to conduct a parameter sensitivity analysis for a two-room fire, and some informative results are given and discussed.

Journal ArticleDOI
TL;DR: In this article, variations in the strength, application time and geometry of the ignition burners used in the furniture calorimeter are studied and the results showed that the burning behaviour of the furniture was almost independent of the burner intensity in the applied regime.
Abstract: When measuring the production rates of heat and smoke of upholstered furniture the ignition source must not influence the test results. In this paper variations in the strength, application time and geometry of the ignition burner used in the furniture calorimeter are studied. Results from replicate furniture calorimeter chair test show that the burning behaviour is almost independent of the burner intensity in the applied regime. Tests on six different furniture items were performed in the furniture calorimeter. The test objects were exposed to three intensity levels of ignition source. The sources were: a large propane burner giving 30 kW during 120 s and a smaller propane burner used at two levels of heat output, 1.7 and 5.8 kW during 90 s. The results showed that the burning behaviour of the furniture was very similar regardless of which burner was used. This was especially evident when the time regime between 50 and 400 kW was studied. The length of this period is a measurement on how quick untenable conditions are developing in a single, well-ventilated compartment. (Less)

Journal ArticleDOI
TL;DR: In this article, the authors report on the ignitability of common siding materials that could be exposed to wildland fires when exposed to brands or fires, structures will experience piloted ignition, which is requisite for sustained ignition involving burn-through and surface flame spread in various directions.
Abstract: This paper reports on the ignitability of common siding materials that could be exposed to wildland fires When exposed to brands or fires, structures will experience piloted ignition, which is requisite for sustained ignition involving burn-through and surface flame spread in various directions In this study, the Lateral Ignition and Flame Spread Test (LIFT) apparatus (ASTM E1321 and E1317) was used to test various siding materials (plywoods, softwoods, and vinyl), some of wbich were painted, humidified, or sawed A recently developed protocol provided useful, accurate values of the following thermophysical properties : surface emissivity, surface ignition temperature, tbermal conductivity, and thermal diffusivity Full consistency was achieved with independent literature values of these properties and can be used directly in the database of fire growth models

Journal ArticleDOI
TL;DR: In this paper, the effects of furnace depth (2.5m and 0.5 m), type of furnace lining material type (fireclay brick, insulating firebrick and ceramic fibre insulation) and type of fuel (gas or liquid) on fire severity in fire resistance test furnaces using the CAN/ULC-S101, ASTM E119 and ISO 834 time-temperature relationships were discussed.
Abstract: This paper discusses the predicted results obtained from models developed to determine the effects of furnace depth (2.5 m and 0.5 m), type of furnace lining material type (fireclay brick, insulating firebrick and ceramic fibre insulation) and type of fuel (gas or liquid) on fire severity in fire resistance test furnaces using the CAN/ULC-S101, ASTM E119 and ISO 834 time-temperature relationships. The type of fuel used in the furnace and the type of furnace wall lining material significantly affected the heat absorbed by the test specimen while the furnace depth effect was minimal when the furnace was lined with ceramic fibre insulation. Factors to improve the repeatability and reproducibility of the fire severity in fire resistance test furnaces are provided.

Journal ArticleDOI
TL;DR: A collaborative industry-government research program was carried out at the National Research Council Canada (NRC) to develop new sound-transmission class and fire-resistance ratings for gypsum-board protected walls as discussed by the authors.
Abstract: A collaborative industry-government research program was carried out at the National Research Council Canada (NRC) to develop new sound-transmission-class and fire-resistance ratings for gypsum-board protected walls. Forintek Canada Corp. and the Canadian Wood Council participated in the program on behalf of Canada's wood industry. As a result of that NRC research program, sound-transmission-class (STC) and fire-resistance (FR) ratings were formulated for approximately 140 gypsum-protected wood-frame walls. Fire-resistance ratings for the walls range from 30 minutes to 2 hours. Sound-transmission-class ratings range from 30 to 65. Sound-transmission-class and fire-resistance ratings for approximately 90 of the wall designs appear in tbe 1995 edition of the National Building Code of Canada (NBCC). This paper highlights some of those STC and FR ratings and describes how they were derived from the data obtained through the research program.

Journal ArticleDOI
TL;DR: In this article, the thermal decomposition of azobisisobutyronitrile (AIBN) was studied under fully adiabatic conditions in a sealed bomb using an accelerating rate calorimetry technique (ARC).
Abstract: The thermal decomposition of azobisisobutyronitrile (AIBN) has been studied under fully adiabatic conditions in a sealed bomb using an accelerating rate calorimetry technique (ARC). Data relating to temperature, pressure and time have been discussed. AIBN decomposes exothermally and the onset of decomposition occurs at 56.19°C. The reaction reaches its maximum at 112.28°C. During this temperature range, the self-heat rate, and the time to maximum rate of the reaction were evaluated. The experimental data have been also treated to evaluate the activation energy of the potential runaway reaction.

Journal ArticleDOI
TL;DR: In this article, the autoignition temperature of 32 polymers at an elevated oxygen pressure of 10.3 MPa was investigated and the heat of combustion was reported for each polymer.
Abstract: Autoignition temperature and heat of combustion are two important parameters in determining the oxygen compatibility of materials. This study investigates the autoignition temperature of 32 polymers at an elevated oxygen pressure of 10.3 MPa and reports their heat of combustion. © 1996 by John Wiley & Sons, Ltd.

Journal ArticleDOI
TL;DR: In this paper, a series of treated fabrics with different oil contamination percentages was investigated and compared, and the results showed that the time-to-ignition of the contaminated samples has notably decreased at relatively low temperatures (350-450°C).
Abstract: The purpose of this study is to evaluate the effect of different oil contaminants on the spontaneous ignition behavior of cotton fabric. A series of treated fabrics with different oil contamination percentages was investigated and compared. Measurements were designed and carried out to determine the average time-to-ignition and to study the thermal behavior of systems containing cellulose. The results showed that the time-to-ignition of the contaminated samples has notably decreased, particularly at relatively low temperatures (350-450°C). However, at higher temperatures such effects became insignificant. Differential Thermal Analysis measurements were used to explain the mechanism by which the oils affect the thermal behavior of the sample. The heat evolved due to the oxidation of the oil content is sufficient to increase the rate of cotton depolymerization at the expense of the dehydration mechanism. In other words, the heat evolved promotes the formation of volatiles which are not char precursors.

Journal ArticleDOI
TL;DR: The philosophy behind research into personal protection from flame and intense heat for UK military personnel is addressed in this article, as well as methods of measurement and assessment, and an overview of the novel techniques which are being pursued at the Science and Technology Division is given.
Abstract: The philosophy behind research into personal protection from flame and intense heat for UK military personnel is addressed. The threat is examined as are methods of measurement and assessment Finally an overview of the novel techniques which are being pursued at the Science and Technology Division is given.

Journal ArticleDOI
TL;DR: The NORDTEST NT FIRE 047 test method needs to be revised and completed in the sections on apparatus, calibration routines, analysis procedure, and expression of results as mentioned in this paper.
Abstract: The Fourier Transform infrared spectrometer method is developed by VTT Fire Technology in Finland, and is described by NORDTEST as NT FIRE 047. The method takes gas samples from the ventilation duct of a cone calorimeter, and is used to perform dynamic quantitative or qualitative measurements. This is an important step in the direction of continuous measurements of gas components in fire smoke. A lot of effort, knowledge and funds are required for a proper calibration and use of this equipment. The experience with application and interpretation of the test method is reviewed in regard to mounting, calibration and use of the equipment. The work concludes that the NORDTEST NT FIRE 047 test method needs to be revised and completed in the sections on apparatus, calibration routines, analysis procedure and expression of results. The missing information and details can lead to differences in application of the method. Until a revised document appears, frequent communication between laboratories can eliminate these differences.

Journal ArticleDOI
TL;DR: The Combustion Behaviour Behaviour of Upholstered Furniture (CBUF) project as mentioned in this paper was a collective effort of 11 CBUF partners, laboratories, universities, industries, in eight countries.
Abstract: This paper gives an overview of the Combustion Behaviour of Upholstered Furniture (CBUF) project. The work described is the collective effort of 11 CBUF partners, laboratories, universities, industries, in eight countries. It became possible to do this research thanks to the European Commission's interest in the burning behaviour of upholstered furniture and their willingness to sponsor this effort. The opportunity to work with many of the most prominent fire researchers and furniture experts has been extremely rewarding. All the expertise of these scientists has resulted in many research results that are presented here. The article only gives the main findings and conclusions of the project, namely the presentation of the fire safety design procedure of the CBUF project. Other articles will deal with specific modelling topics and an extensive description of the project can be found in the final CBUF report EUR 16477 EN.

Journal ArticleDOI
TL;DR: In this article, it was observed that DMU reacts bifunctionally with glucopyronosyl hydroxyls in such a way that a three-dimensional (hence more stable) structure develops in addition to the possibility of release of acid residues within the flaming zone.
Abstract: Samples of unscoured, scoured, bleached and mercerized cellulosic fabrics were treated with dimethylol urea (DMU). It was observed that this treatment imparted to the fabrics flame retardant (FR) characteristics. These observations were interpreted in terms of the fact that DMU reacts bifunctionally with glucopyronosyl hydroxyls in such a way that a three-dimensional (hence more stable) structure develops in addition to the possibility of release of acid residues within the flaming zone.

Journal ArticleDOI
TL;DR: In this paper, a possible explanation for the differences found between the fire behaviour of materials in small-scale cone calorimeter tests and the large-scale furniture calorimeters is presented.
Abstract: In this paper a possible explanation is presented for the differences found between the fire behaviour of materials in small-scale cone calorimeter tests and the large-scale furniture calorimeter. The results obtained with cone calorimeter/FTIR equipment at 35 kW m -2 will show that the early flash ignitions of typical materials like cotton and wool are due to the liberation of flammable gases during the pyrolysis phase and the typical ignition situation on the cone calorimeter, that is, the presence of a sparking igniter above the sample. This fast flash ignition and the early heat release behaviour on the cone calorimeter may be in contradiction to the early fire growth in other fire tests where the ignition conditions are clearly different from pyrolysis circumstances, that is, ignition via a burning newspaper, match, gas flame, etc.


Journal ArticleDOI
TL;DR: In this paper, Fourier Transformed Infrared (FTIR) spectroscopy is used to monitor the evolved gases from a furniture calorimeter, but if concentration-time profiles are needed, compromises between spectral resolution, time resolution and sensitivity may have to be made, and the presence of significant noise levels limits the information that can be obtained from the infrared spectra.
Abstract: Fourier Transformed Infrared (FTIR) spectroscopy may be used to monitor the evolved gases from a furniture calorimeter, but if concentration-time profiles are needed, compromises between spectral resolution, time resolution and sensitivity may have to be made, and the presence of significant noise levels limits the information that can be obtained from the infrared spectra. In this paper we demonstrate that the data may be satisfactorily treated by factor analysis to identify and reject factors attributable to noise. Subsequent reconstruction produces the original spectra with little or no noise and without significant loss of information. The reconstructed spectra were found to contain useful qualitative information even for the background spectra. By comparison, the traditional method of signal averaging for noise reduction not only leads to inferior spectra but also has a substantial disadvantage for fire gas monitoring because it leads to loss of information in poor time resolution, limiting the applicability of the FTIR spectroscopy to follow the combustion process.