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1.
A statistical study of fires in the United Kingdom involving the ignition of furniture and furnishings is presented. This paper examines the data for one year (1970). The analysis shows that in fires starting in furniture and furnishings the chance of a fatality is over twice that in other domestic fires. The majority of furniture fires involve upholstery or bedding and over 90% were started by smokers' materials, electric appliances, space heating or as the result of the activities of children or suspected arsonists. Eighty-five percent of the fatalities were found in the room of origin of the fire. Eighty per cent were overcome by smoke or toxic gases. Sixty percent of the fatalities were either under 5 or over 65 years of age. Monetary values are assigned for damage, casualties and deaths in fire. These costs can be used to assess the value of fire precautions. With the values taken, the total losses in furniture fires in the home amounted to £19 million in 1970. Life loss accounted for the major part of this sum. The expected annual loss per dwelling as a result of the ignition of furniture is thus only about £1, and is only £3 for all dwelling fires. This low figure suggests an approach of either selective spending on those most at risk (the elderly and handicapped) or by government activity through publicity and education. 相似文献
2.
There is widespread concern at present about the fire risk form the use of modern materials in upholstery and other domestic articles. One of the main characteristics of fires in dwellings which start with the ignition of textiles or furniture is that they have a high casualty rate compared with other kinds of domestic fires. Most of the casualties form such fires occur in fires which start in upholstery or bedding, often accidentally ignited by smokers' materials. Asphyxiations by smoke is the commonest cause of death in ‘textile’ and ‘upholstery’ fires. This paper presents relevant statistical information on fires in dwellings attended by local authority fire brigades which result from the ignition of upholstery, bedding, other textiles or furniture and the casualties which these fires cause. 相似文献
3.
The effectiveness and the failure mechanism of fire barriers in a residential upholstered furniture (RUF) were investigated by full-scale flaming tests on upholstered chair mock-ups. Six commercial fire barriers were tested in this study. Fire barriers were screened for the presence of elements that are typically used in fire retardants and the presence of commonly used fire retardants. For each fire barrier, triplicate flammability tests were run on chair mock-ups, where polyurethane foam and polyester fiber fill were used as the padding materials, and each chair component was fully wrapped with the fire barrier of choice and a polypropylene cover fabric. The ignition source was an 18 kW square propane burner, impinging on the top surface of the seat cushion for 80 seconds. Results showed all six fire barriers reduced the peak heat release rate (as much as ≈64%) and delayed its occurrence (up to ≈19 minutes) as compared to the control chair mock-ups. The heat release rate remained at a relatively low plateau level until liquid products (generated by either melting or pyrolysis of the padding material) percolated through the fire barrier at the bottom of the seat cushion and ignited, while the fire barrier was presumably intact. The flaming liquid products dripped and quickly formed a pool fire under the chair, and the peak heat release rate occurred shortly thereafter. Ultimately, the ignition of the percolating liquid products at the bottom of the seat cushion was identified as the mechanism triggering the failure of the fire barrier. 相似文献
4.
Experimental determination of fire heat release rate with OC and CDG calorimetry for ventilated compartments fire scenario
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This research deals with the experimental determination of the heat release rate (HRR) of fires in mechanically ventilated compartments based on oxygen consumption (OC) and carbon dioxide generation (CDG) calorimetry. It proposes formulations for fire in force‐ventilated compartments on the same basis as the relations established for hood calorimetry in an open atmosphere but considering inertia and unsteady behavior of the fire via the time variation mass of O2 and CO2 in the compartment. The value of the new formulations of HRR has been tested in two series of propane gas fire experiments performed in a large‐scale facility. The first series involves a fire scenario with one compartment, and the second series, a fire scenario with three compartments connected to each other by doorways. In the first test series, the OC and CDG formulations for HRR are assessed. In the second test series, the OC and CDG formulations are presented with two approaches to definition of the control volume: approach involving three rooms and the flow rate in the ventilation network and approach involving only the fire room and the flow rate through the doorways. On the basis of the fire experiments considered, the most accurate method (accuracy to within 10%) for determining the HRR is the CDG formulation with approach for the control volume without considering the flow rates at the doorways. This analysis points out the different features of each method (OC and CDG) and thoroughly discusses their advantages and drawbacks. The overall analysis allows guidelines to be formulated for fire HRR calculation in confined and ventilated compartments. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
5.
The storage of large amounts of polymers and other bulk chemicals is a potential hazard in the case of fire. There is at present a lack of knowledge about the implications of such fires. In particular the role of the ventilation conditions on fire chemistry has warranted investigation. A set of indoor, large‐scale combustion experiments, conducted on five different materials is described in this article. The main test series was conducted using the ISO 9705 room, where both well‐ventilated and under‐ventilated conditions were attained by restricting the opening of the room. The degree of ventilation was determined using a phi meter. Furthermore, in addition to measuring the traditional fire‐related parameters, extensive chemical characterization of the combustion products was made. Two additional series of experiments were also performed. In one series of tests the size of the enclosure was increased and the fuel was placed in a storage configuration to simulate a real storage situation. In the other test series, three of the materials were tested as large‐scale open pool fires. The results from the three configurations are compared regarding yields of combustion products as a function of the degree of ventilation. For a number of toxic combustion products a clear dependence of the production on the equivalence ratio was found. Further, placing the fuel in a storage configuration did not significantly change the outcome of the combustion. Thus, the ISO 9705 room is of a size and scale that can be taken as a model for representing real‐scale fires. Additionally it has been demonstrated that an advantage of the ISO 9705 room is the ability to alter the ventilation conditions. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
6.
This paper presents the fire load data in educational, office and library buildings, obtained through an extensive inventory survey. This data collection effort is prompted by a growing need to simulate compartment fires, wherein estimating realistic fire scenarios is essential to assess the level of fire severity in a structure, and consequently the strength of the various structural members at elevated temperatures. The attributes of compartment fires primarily depend upon the fuel load and its composition, compartment dimensions, ventilation characteristics, and construction materials. Despite an acute need, fire load data across the world is scarce and outdated, and does not reflect the change in the type of materials in-use today. The survey data presented in this paper is collected from 108 rooms in 10 educational buildings, 51 rooms in three office buildings, and 13 rooms in a library building. This paper also presents the composition of fire loads and the levels of ventilation in these buildings. The studies show that fire loads can vary significantly depending on the room-use; thereby basing fire load values solely on the overall category of a building may result in either conservative or unsafe design. This study also finds that certain room types (e.g., computer labs) have significant plastic-based fuels, indicating that typical modelling recommendations based on cellulosic fuels for heat release rate, combustion heat, etc. may not always be appropriate. The paper finally examines the statistical distribution that best describes the measured values of the fire load densities. 相似文献
7.
Eric Guillaume Virginie Dréan Bertrand Girardin Faiz Benameur Maxime Koohkan Talal Fateh 《火与材料》2020,44(1):35-57
The dramatic event of the Grenfell Tower (June 2017), involving a combustible façade system, has raised concerns regarding the fire risk that these systems address. Indeed, as façades are complex systems, it is not straightforward to assess which part of the system is involved in the global fire behaviour. Understanding such façade fires is thus very complex as it depends on a combination of various products and system characteristics, including window frames or air gap or cavity barriers. Fire development inside the initial apartment was investigated using an appropriate CFD model with different scenarios for the fire source and ventilation conditions in a previous study. Fire propagation through the window to the external façade and to higher apartments was modelled and validated against visual observations. This paper describes CFD modelling of the complete Grenfell tower facade, and investigates vertical fire spread behaviour over the full height façade from the initial apartment. Contributions from the combustion of all the apartments' furniture, depending on window failure, and architectural details of the refurbished façade are considered in the numerical model. The modelling results are validated by comparison with photographic and video observations of the real fire. 相似文献
8.
Richard G. Gann 《火与材料》2021,45(1):3-7
Fires in which soft furnishings (upholstered furniture and beds) were either the first item ignited or were identified as the major item in the fire's growth are the deadliest of residential fires. This Special Issue of Fire and Materials on Furniture Flammability grew from a small session on this subject in Interflam 2019. The issue contains 14 papers that describe the fire problems of soft furnishings, research to better understand their burning behavior, and recent success in and promising approaches to reducing the losses from these fires. This introduction concludes with the author's challenges to the fire safety community for reducing the number and consequences of soft furnishings fires. 相似文献
9.
Beds are a prevalent combustible in fatal fires in the United States effective 1 July 2007, the US Consumer Product Safety Commission promulgated a standard to severely reduce the heat release rate and the early heat output from mattresses and foundations when ignited by a flaming ignition source. This study estimates the Standard's success over its first decade using fire incidence, US population, and mattress sales data. The technique mitigates the influence of some exogenous factors that might have changed during this decade. The Standard is accomplishing its purpose, preventing approximately 65 fatalities (out of an estimated 95 fatalities in 2002‐2005) from bed fires annually during 2015‐2016, although not all pre‐Standard mattresses had yet been replaced. Compared to residential upholstered furniture fires, which were not affected by the Standard, the numbers of bed fires decreased by 12%, injuries by 34%, and deaths by 82% between 2005‐2006 and 2015‐2016. Per bed fire, injuries decreased by 25% and fatalities decreased by 67%, indicating that the severity of bed fires is being reduced. 相似文献
10.
Many fatal residential fires started from burning upholstered furniture, and so upholstered furniture fire has been studied rather extensively in developed countries. As many upholstered furniture were made in China, the hidden fire risk should be studied more. In this paper, full‐scale experiments on the burning of upholstered furniture manufactured in China were conducted and analyzed. The oxygen consumption method was used to measure the heat release rate in a room calorimeter. An ignition source of a 20‐kW gasoline pool fire of 0.2‐m diameter was used to test square foam cushions and 4‐seater sofas. A model of heat release rate predicting upholstered furniture fire in a room was developed on the basis of earlier Swedish works. Results were then used to justify the application of the Combustion Behaviour of Upholstered Furniture model to predict the heat release rate of furniture manufactured in China. The numerical values of key parameters in the model were determined. It is proposed to build up a database that can be used to model heat release rates upon burning furniture. Detailed procedures are illustrated in this paper. 相似文献
11.
‘Normalized heat load’ is a quantifier of the destructive potential of fires, real-world compartment fires and test fires alike. For real-world fires it is subject to some uncertainties owing to the random nature of two of the variables it depends on: ventilation and fire load. For test fires also it is subject to uncertainties owing to a moderate degree of randomness that characterizes the results of test fires. A procedure is described for predicting the failure probability in fire of the boundaries of a compartment designed for fire resistance on the basis of information concerning the characteristics of the compartment and the design value of the fire load. The procedure is essentially deterministic, employing statistical considerations only as far as required by the nature of some of the input variables. With the aid of second-moment analysis, it is possible, furthermore, to design the compartment boundaries for appropriate target failure probabilities. 相似文献
12.
Archibald Tewarson 《火与材料》2003,27(3):131-149
Eight free burning and two sprinklered fire tests were performed with electrical cable trays and live digital switch racks in a large enclosure to simulate telecommunications central office (TCO) fires started by electrical overheating. Very‐slow‐growing (non‐flaming), slower‐growing (partially flaming) and low‐intensity‐faster‐growing (flaming) fires releasing gray‐white, gray, and black smoke, respectively, were observed in the tests. Under quiescent conditions present in the unvented enclosure fire tests for cables, very‐slow‐growing fires were detected in about 1452 s, whereas the slower‐growing fires were detected in about 222 s by commercial fire detectors. Under ventilation conditions typical of TCOs, detection times were very similar for the five types of commercial TCOs fire detectors used in the tests. The average detection times for slower‐growing fires (cable fires) and low‐intensity‐faster‐growing fires (digital switch rack fires) were 242±17% and 249±11%s respectively. The TCO procedures to reduce smoke damage from fires (on fire detection, inlet ventilation flow is turned off and exhaust flow is turned on) were found to be beneficial. The extent of smoke damage decreased significantly with an increase in the exhaust flow rate. The chloride ion mass deposition suggested that equipment recovery would be possible in the smoke environment if the cable vapor concentration could be reduced below about 3 g/m3. The metal corrosion rate was found proportional to the 0.6th power of the smoke concentration, similar to that found for the corrosion of metal surfaces exposed to aqueous solutions of HCl and HNO3 and for acid rain with no protective layer at the surface. Sprinkler water was found to wash down the smoke deposits on the surfaces with little indication of corrosion enhancement. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
13.
This paper reviews the current literature on the behaviour of thermoset polymers under fire conditions. These polymers are important and widely used materials. They are generally infusible and insoluble, and consist, on the molecular scale, of extensive cross-linked networks rather than discrete macromolecules. Materials in this class include phenol-formaldehydes, epoxides, cross-linked polyester, amino resins and polyurethanes. As the use of plastics generally has grown, so there have been changes in the conditions prevailing in modern fires, and such changes are described, together with the potential fire hazards arising from the varying uses of the individual thermosets. Subsequently, literature on the pyrolytic and combustion characteristics of these materials is reviewed in order to assess their probable behaviour in real fires. Finally, existing approaches towards improving their fire behaviour are described. 相似文献
14.
The critical ventilation velocity is almost the most well‐investigated fire phenomenon in the tunnel fire research field whereas previous studies have always investigated it when the fire source is distant from the downstream tunnel exit. Fortunately, a recent study provided a set of data on the critical ventilation velocity for tunnel fires occurring near tunnel exits by small‐scaled experiments, nevertheless, with a lack of further analysis. To demonstrate the relationship of the critical ventilation velocity and the distance between the fire and tunnel exit more explicitly and detailedly, a quantitative and graphical study was carried out and a correlation was presented in this paper. Inspired by this, a set of small‐scaled experiments were carried out to investigate the influence of different longitudinal fire locations on maximum smoke temperature under the tunnel ceiling. Results show that unlike the critical ventilation velocity, the maximum smoke temperature was not obviously affected by longitudinal fire location. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
15.
Cable fires are one of the main fire hazards in nuclear power plants. As part of the cable fire spreading (CFS) campaign of the OECD PRISME‐2 programme, 3 real‐scale cable tray fire tests were performed in open atmosphere (1 CFS support test, named CFSS‐2) and in a confined and mechanically ventilated facility (2 CFS tests, named CFS‐3 and CFS‐4). This study aims at investigating the effects of confined and ventilated conditions on cable tray fires that used a halogen‐free flame retardant cable‐type. The CFS‐3 and CFS‐4 tests involved 2 ventilation renewal rates of 4 and 15 h?1, respectively. The confined conditions lead to decrease the fire growth rate and the peaks of mass loss rate and heat release rate, compared with open atmosphere. The reductions are larger for the lower ventilation renewal rate. Furthermore, it is shown that the CFS‐4 test may be classified as a well‐ventilated fire and the CFS‐3 test as an under‐ventilated fire. For this last one, its fire characteristics and its consequences in the fire room highlight an oscillatory behaviour, with the same low frequency, for about 30 minutes. These oscillations arise from successive combustions of unburnt gases. 相似文献
16.
Marcelo M. Hirschler 《火与材料》2017,41(8):993-1006
This work provides an up‐to‐date review of the fire properties of poly(vinyl chloride) (PVC) materials, both rigid (unplasticized) and flexible (plasticized). The fire properties addressed include ignitability, ease of extinction (oxygen index), flame spread (small scale and intermediate scale), heat release, smoke obscuration, smoke toxicity, hydrogen chloride emission and decay, and performance in real‐scale fires. This comprehensive review includes a wide selection of references and tables illustrating the properties of PVC materials in comparison with those of other polymeric materials, including, in many instances, wood materials. The work puts these fire properties in perspective, showing that the heat release rate (the key fire property) of rigid PVC (and that of properly flame‐retarded flexible PVC) are among the lower values found for combustible materials. This work also shows that the smoke toxicity and smoke obscuration resulting from burning PVC materials in real‐scale fires is in the same range as those of other materials. 相似文献
17.
Marty Ahrens 《火与材料》2021,45(1):8-16
Home fires in which soft furnishings were first ignited or contributed to fire spread cause a disproportionate share of US home fire deaths. Although the death toll from these fires is much lower than in the 1980s, the rate of death per 1000 reported fires has doubled. Data from the National Fire Incident Reporting System and the National Fire Protection Association's annual Fire Experience Survey were used to create national estimates of these fires and casualties. Including both fires in which upholstered furniture was the item first ignited and contributed most to fire spread, in 2013‐2017, upholstered furniture was involved in an estimated average of 7120 (2%) home fires per year, resulting in an average of 570 (22%) deaths per year. Mattresses or bedding were involved in estimated average of 10 530 (3%) home fires per year, resulting in an average of 370 (14%) deaths annually. In most of these fires and deaths, the item was first ignited. Smoking materials were the leading cause of these fires (20%‐26%) and associated deaths (52%‐54%). Various types of operating equipment and small open flames also play a role. Understanding the causes of these fires is essential to develop new strategies to prevent them. 相似文献
18.
The paper focuses on the detailed characterization of ventilation controlled fires of industrial products that are likely to govern accidental fire scenarios in fire resistant enclosures. Results regarding under‐ventilated fires of substances that are not polymers are presented to illustrate the capability of the fire propagation apparatus (FPA) to qualify such types of fires. Based on results from heptane fire tests in both well‐ and under‐ventilated fire conditions, a set of recommendations was previously provided in order to check the validity of the experimental results. The application of these recommendations is illustrated for the selected liquid substances containing hetero‐atoms. It emerges that the fire propagation apparatus assesses quite easily the performance of well‐controlled fires in both well‐ and under‐ventilated conditions. Another major outcome of our work is that the potential of the FPA has the capability to address fire issues outside the conventional use of the equipment, in particular to qualify the burning behaviour of chemicals on the full spectrum of ventilation conditions. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
19.
A literature review was performed to assess the state of knowledge of the effects of railcar interior finish materials on fire growth and fully developed fires from railcars. An overview is provided on standards and requirements currently used to regulate interior finish materials. Following this review, an overview of experimental and computational research is provided on railcar interior finish flammability and its impact on fire growth. A survey of the research on fully developed fires and the potential heat release rates of railcars is then presented. This includes scaling laws, experimental research, and model development. Future research recommendations are then presented. 相似文献
20.
Several -i-isocyanates have become commercially important materials, used as intermediates in the manufacture of a wide variety of polyurethane products, yet little is recorded on their behaviour if involved in fire. This paper describes a series of programmes carried out under the auspices of the International Isocyanate Institute Inc. First, a small-scale laboratory investigation of the ignition, heat release, smoke and toxic gas production characteristics of di-isocyanates was carried out. Second, their behaviour in drumstock and pool fires, respectively, was examined, using full-sized samples and selected real-fire scenarios. Part 1 records the results for toluene di- isocyanate (TDI) showing the need for a modest energy input to ignite it from a pilot flame. It then burns in a steady rather than vigorous manner, leaving no residues. Toxic gases evolved are mainly carbon monoxide, while free isocyanate is likely in the early stages of the fire, and hydrogen cyanide may be important in well-developed fires. Drumstock material behaviour in a fire is dictated mainly by the rupture characteristics of the containers, which can be violent. A series of simple guidelines is suggested, which includes the need for firefighters to wear full protective clothing and fresh-air breathing equipment. It is also recommended that drumstock TDI should be stored away from easily ignitable materials. 相似文献