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Background: In Pedróg?o Grande on 17 June 2017, two fire fronts merged and the propagation of the fire was influenced by the interaction of these non-symmetric fire fronts. Aims: This wildfire motivated us to study a junction fir...
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Background: In Pedróg?o Grande on 17 June 2017, two fire fronts merged and the propagation of the fire was influenced by the interaction of these non-symmetric fire fronts. Aims: This wildfire motivated us to study a junction fire with two non-symmetrical fire fronts. The analysis of the movement of the intersection point and the angle (γ) between the bisector of the fire lines and the maximum rate of spread (ROS) direction is of particular relevance. Methods: The study was carried out at Forest Fire Laboratory of the University of Coimbra in Lous? (Portugal) with laboratory experiments. Key results: We found that, for small rotation angles (δ), the non-dimensional ROS of the intersection point depends on the slope angle (α) and the initial angle between fire fronts. Conclusions: For high α, the non-dimensional ROS was highly influenced by the convection process and γ where the maximum ROS occurred, increased when δ increased. However, the radiation process was more relevant for lower α and influenced the non-dimensional ROS. For these cases, the maximum spread direction was close to that of the fire line bisector. Implications: The present work aimed to explain fire behaviour during the Pedróg?o Grande wildfire.
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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 M...
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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.
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In 2017 the UK Health and Safety Executive commissioned a report (MH/17/27) on the suitability of the ISO 22899-1:2007 jet fire resistance test (JFRT) as a means of demonstrating performance of Passive Fire Protection (PFP) materi...
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In 2017 the UK Health and Safety Executive commissioned a report (MH/17/27) on the suitability of the ISO 22899-1:2007 jet fire resistance test (JFRT) as a means of demonstrating performance of Passive Fire Protection (PFP) materials or systems to a range of jet fire scenarios. The aim was to address current industry concerns regarding the suitability of the test for characterising PFP materials response in' high heat flux' scenarios.
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Most fire-related injuries and fatalities in the UK, and other parts of the world, continue to occur during fires in the home incidents where it is acknowledged that human factors play a contributing role. Yet the field of fire sa...
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Most fire-related injuries and fatalities in the UK, and other parts of the world, continue to occur during fires in the home incidents where it is acknowledged that human factors play a contributing role. Yet the field of fire safety lacks an up-to-date review of the literature on human behaviour during fires in domestic spaces. Given there is now a growing body of work looking at human behaviour in dwelling fires, a review of the literature in this area is timely. Drawing from published studies, this paper sets out what is currently known about human behaviour in dwelling fires and highlights the differences that appear to exist between these spaces and what is known and accepted about human behaviour in public, commercial and industrial spaces. This paper then goes on to consider the nature of "fire risk", arguing that much of the work in this area continues to conflate, or fails to recognise the existence of, different types of risk profiles, instead considering fire risk as a single type of risk, based mainly on factors related to fatalities. However, research findings point towards fire risk as at least three separate forms: the risk of a fire occurring, the risk of fire injury and the risk of fire fatality. By drawing together the literature on human behaviour in dwelling fires this paper argues that those who survive dwelling fires cannot be considered as "near miss fatalities", but instead must be treated as a separate and distinct group.
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Developments in the understanding of fire behaviour for large open-plan spaces typical of tall buildings have been greatly outpaced by the rate at which these buildings are being constructed and their characteristics changed. Nume...
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Developments in the understanding of fire behaviour for large open-plan spaces typical of tall buildings have been greatly outpaced by the rate at which these buildings are being constructed and their characteristics changed. Numerous high-profile fire-induced failures have highlighted the inadequacy of existing tools and standards for fire engineering when applied to highly-optimised modern tall buildings. With the continued increase in height and complexity of tall buildings, the risk to the occupants from fire-induced structural collapse increases, thus understanding the performance of complex structural systems under fire exposure is imperative. Therefore, an accurate representation of the design fire for open-plan compartments is required for the purposes of design. This will allow for knowledge-driven, quantifiable factors of safety to be used in the design of highly optimised modern tall buildings. In this paper, we review the state-of-the-art experimental research on large open-plan compartment fires from the past three decades. We have assimilated results collected from 37 large-scale compartment fire experiments of the open-plan type conducted from 1993 to 2019, covering a range of compartment and fuel characteristics. Spatial and temporal distributions of the heat fluxes imposed on compartment ceilings are estimated from the data. The complexity of the compartment fire dynamics is highlighted by the large differences in the data collected, which currently complicates the development of engineering tools based on physical models. Despite the large variability, this analysis shows that the orders of magnitude of the thermal exposure are defined by the ratio of flame spread and burnout front velocities (V_S/ V_(BO)), which enables the grouping of open-plan compartment fires into three distinct modes of fire spread. Each mode is found to exhibit a characteristic order of magnitude and temporal distribution of thermal exposure. The results show that the magnitude of the thermal exposure for each mode are not consistent with existing performance-based design models, nevertheless, our analysis offers a new pathway for defining thermal exposure from realistic fire scenarios in large open-plan compartments.
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A survey of ophthalmic plastic and reconstructive surgeons as well as seven-year data regarding claims made to the Ophthalmic Mutual Insurance Company (OMIC) is used to discuss operating room fires in periocular surgery.
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Human land use practices, altered climates, and shifting forest and fire management policies have increased the frequency of large wildfires several-fold. Mitigation of potential fire behaviour and fire severity have increasingly ...
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Human land use practices, altered climates, and shifting forest and fire management policies have increased the frequency of large wildfires several-fold. Mitigation of potential fire behaviour and fire severity have increasingly been attempted through pre-fire alteration of wildland fuels using mechanical treatments and prescribed fires. Despite annual treatment of more than a million hectares of land, quantitative assessments of the effectiveness of existing fuel treatments at reducing the size of actual wildfires or how they might alter the risk of burning across landscapes are currently lacking. Here, we present a method for estimating spatial probabilities of burning as a function of extant fuels treatments for any wildland fire-affected landscape. We examined the landscape effects of more than 72 000 ha of wildland fuel treatments involved in 14 large wildfires that burned 314 000 ha of forests in nine US states between 2002 and 2010. Fuels treatments altered the probability of fire occurrence both positively and negatively across landscapes, effectively redistributing fire risk by changing surface fire spread rates and reducing the likelihood of crowning behaviour. Trade offs are created between formation of large areas with low probabilities of increased burning and smaller, well-defined regions with reduced fire risk.
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Three full-scale fire experiments were conducted to assess methods of hardening the motorcoach against penetration of a tire fire. The first method was to replace the combustible fender and exterior side panel above the wheels wit...
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Three full-scale fire experiments were conducted to assess methods of hardening the motorcoach against penetration of a tire fire. The first method was to replace the combustible fender and exterior side panel above the wheels with stainless steel sheet metal. The second method was to coat the plastic fender and side panel with an intumescent layer. The third method was to install a sheet steel fire plume deflector between the fender and side panel. A special burner was used that imitates the frictional heating of hub and wheel metal caused by failed axle bearings, locked brakes, or dragged blown tires. For each experiment, heating to obtain tire ignition was initiated on the exterior of the passenger side tag axle wheel. Measurements of interior and exterior temperatures, interior heat flux, and heat release rate were performed. Standard and infrared videos and still photographs were recorded. The experimental results were compared with those obtained with no fire hardening. The metal replacement method performed best and prevented fire penetration for over 30min longer than the nonhardened cases. The intumescent coating extended fire penetration by about 20min longer than the nonhardened cases. The steel plume deflector had no significant impact on the timing for fire penetration of the windows. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
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The concept of fire regime refers to a variety of fire characteristics occurring at a given place and period of time. Understanding fire regimes is relevant to fire ecology and fire management because it provides a better understa...
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The concept of fire regime refers to a variety of fire characteristics occurring at a given place and period of time. Understanding fire regimes is relevant to fire ecology and fire management because it provides a better understanding of effects of fire as well as the potential effects of different future scenarios. Recent changes in the traditional fire regimes linked to climate and socioeconomic transformations in European Mediterranean areas have influenced fire regimes and their effects on both ecosystems and people. This paper presents a methodology for characterising fire regimes based on historical fire statistics. The analysis includes three dimensions: density, seasonality and interannual variability. The raw records were pre-processed to eliminate errors, and a principal component analysis was performed to identify the primary factors involved in the variation. A cluster analysis was then used to define the fire regimes. Approximately 38% of the spatial cells examined were found to have significant fire activity, but in spite that fires are important in these areas, fire activity showed a high interannual variability. Four fire regimes in the Spanish peninsular territory were described in terms of the density and seasonality of fire activity.Digital Object Identifier http://dx.doi.org/10.1071/WF12061
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The work of the fire service has changed during the last decades from being essentially operational to include a larger variety of activities to increase fire safety in society. Also, the theoretical understanding of fire developm...
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The work of the fire service has changed during the last decades from being essentially operational to include a larger variety of activities to increase fire safety in society. Also, the theoretical understanding of fire development, fire dynamics in buildings and fire safety engineering have improved. There are several good examples of areas were fire dynamics theories have supported and improved the fire service activities associated with building fire safety during the last decades. Despite such examples the quality of knowledge transfer between theory and research, and the more practical arena, such as fire service activities is sometimes questionable. This paper includes a systematic literature review and an interview study that is used to discuss how fire dynamics is used to support fire service activities today and where the use of fire dynamics theory could or should be increased in the future. It is found in the paper that fire dynamics theories are currently used more in the preventative and investigative areas than in the operational area of fire service activities. The primary reasons for this is that the timeframe is much shorter in the latter and that there are established procedures and tactics that work well for the common operational situations. However, there is a potential to use fire dynamics theories more in the operational area when it comes to events that occurs less frequent and with a longer duration than for example the normal compartment fire. In general, there is room for improvement of the use of fire dynamics in the fire service and a way forward could be a stronger link between theory and practice in education and training.
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