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This paper mainly investigated the fire resistance of different fire prevention schemes for 1670 MPa steel wires used in bridge cables. The fire resistance tests on bridge cables under different fire protection schemes were carried out. The failure modes and the varied patterns of temperature at different positions of the cables was studied, and the optimal design scheme of fire protection for bridge cables was also obtained. Furthermore, the tensile test of steel wire after fire was carried out to study the degradation law of mechanical properties of steel wire. The results showed that the cables undergo varying degrees of bending deformation after the fire, mainly due to the poor fire protection effect. The wrapping process of the fire protection scheme was a key factor affecting the protective effect. When the premature invalidation of the wrapping mode failed to occur, the aerogel material would have better thermal insulation behavior than the basalt fiber. The temperature rising rate of Schemes D (6 mm ceramic fiber aerogel tape), E (10 mm high silica glass aerogel tape) and F (10 mm nano thermal isolation felt-ceramic fiber aerogel) was relatively gentle, and the temperature of most measuring points within 4500s was not more than 300 °C. Based on the failure mode and the temperature of the cables, it could be judged that Schemes E and F were better than Schemes C (4 mm composite fiber fire-resistant isolation tape) and D while schemes A (4 mm basalt fiber needled felt) and B (4 mm aerogel tape) had the worst fire protection effect. Due to the surface temperature, the fracture morphology of steel wires after fire varied greatly, mainly divided into brittle fracture and ductile fracture. With the increase of temperature, the yield and ultimate strength of steel wire of Schemes A, B, C, D and E decreased greatly after fire, and along with a maximum decrease of 73.78% and 69.02% respectively. [ABSTRACT FROM AUTHOR]

The spatial-temporal characteristics of wildfires were summarized based on fire reports covering 55,863 wildfires with a total burned area of 289.91 km2 from 1995 to 2020 in Japan. The long-term decreasing trend was largely influenced by changes in social aspects, while the annual fluctuation was determined by large-scale events. The wildfire season started around early January in the southern part and gradually shifted northward over approximately three months. A total of 98.77% of cases were human-induced, and 1.23% were caused by lightning. Regarding response time after receiving the call, firefighting was started within 30 min in 89% of cases and controlled within 1 h in 85% of cases, where spatial characteristics were insignificant. Full-time fire departments utilized artificial water sources primarily in 72% of cases and natural water sources in 28%, while the rate using natural water sources increased as the burned area increased. Natural water sources from ponds and rivers exhibited regionalities. Cluster analysis revealed five wildfire regions reflecting natural and anthropogenic factors. Furthermore, the Mann–Kendall trend test concluded that the initiation process decreased almost uniformly across the country, while regional differences existed regarding the expansion process. Additionally, only human-induced wildfires had a significant decreasing trend. • The fire reports of 55,863 wildfire cases from 1995 to 2020 were summarized. • The decreasing trend of the number of fires was significant and human-influenced. • A total of 98.77% of wildfires were human-induced, and 1.23% were by lightning. • Firefighting was started in 30 min in 89% of cases after receiving the call. • 72% of cases used artificial water sources, and large cases needed natural sources. [ABSTRACT FROM AUTHOR]

Continuous fuel spill fires are a common accident scenario which needs to be considered for the safe operation of tunnels, given the potential threat posed to trapped persons. In this paper, a series of continuous spill fire experiments on a concrete surface were studied using a 1/8 reduced-scale tunnel model. Gasoline was used as the discharge fuel and the discharge rate varied from 1.5 to 5.2 ml/s. The burning area, steady regression rate, smoke front arrival time, and ceiling temperature were analyzed. The results show that the burning area spreads slowly following an initial rapid spill stage, with the spread process following a pattern of exponential decay. The steady regression rate is found to be approximately 63% of that of pool fires for the same burning area. At the same heat release rate, the smoke front moves faster for spill fires than pool fires because of the larger burning area, and a correlation is built to predict the smoke front arrival time. Finally, a ceiling temperature rise prediction model is developed which considers the spread and burning processes of the fire. The results are of practical importance in the quantitative risk assessment of liquid fuel fire accidents in tunnels, and their implications for personnel evacuation. • The spread processes of the liquid layer and smoke front of a continuous spill fire are studied in a model-scale tunnel. • The arrival time of the smoke front is smaller for spill fires than for pool fires due to a larger burning area operating. • The regression rate of spill fires is higher in a tunnel than in open space, and is lower on concrete than fireproof glass. • A ceiling temperature rise prediction model is developed and validated by experimental data from the tunnel spill fires. [ABSTRACT FROM AUTHOR]

This study concerns the under-ventilated combustion regimes of a fire scenario in mechanically ventilated enclosures. Using the theoretical approach of the well-stirred reactor model and the data-base of large-scale pool fire tests, the study analyses the mass loss rate as a function of the environmental conditions. The novelties lie in the analysis of a large set of realistic scenarios involving complex geometries (several compartment connected) and new ventilation configurations and the applicability of the well-stirred reactor model to interpret these scenarios. The variables of interest are the combustion regimes (stationary, transient or with rapid quenching), the duration of the combustion phase and the mass loss rate. The results show a satisfactory prediction of the well-stirred reactor model to interpret the experimental results of complex and realistic fire scenario and the robustness of this model to deal with the under-ventilated regimes. The analysis also highlights the interest of two new parameters rarely used in the literature, the ventilation factor and the mass factor, to characterize under-ventilated scenarios. The analysis points out the importance of the relationship expressing the burning rate as a function of environmental conditions (oxygen level and external flux) and extinction conditions. • Under-ventilated combustion regimes in mechanically ventilated enclosures • Effect of oxygen vitiation on the burning rate • Summary analysis from a large-scale fire test database • Application to complex scenarios representative of real fires event [ABSTRACT FROM AUTHOR]

Evaluation of potential fire scenarios and escape outcomes involves data and calculations for many different parameters and their interactions, with uncertainties regarding application to real systems. Assessment of fire development, occupant behaviors and effects of toxic smoke exposure during actual incidents can provide a reality check on engineering methods, data quality, assumptions and limitations. Because incidents encompass the performance of entire occupied built systems, they enable witness accounts, survival, medical and pathology outcomes and evidence of fire development and toxic smoke spread to be combined with fire, evacuation and toxicity modelling calculations. Since outcomes are known, they constrain the predictions derived, revealing previously unidentified parameters and enabling validation of current methodology. Examples from incidents highlight the following findings. • Pre-warning delays – neglected parameter, high consequence. • Effects of fire cues and warnings on occupant behavior and pre-travel times, and stair descent speeds in relation to visibility – generally validate current methods. • Probability of evacuation through irritant smoke– high consequence, needs more consideration. • Times to incapacitation from asphyxiant gases as a function of fuel composition and smoke density – useful assessment method. • Using smoke and carbon monoxide exposure toxicology to estimate fire development and exposure history - Useful method for fire scenario validation, confirms FED method validity. • Fire incident investigation by integration of fire dynamics, behavior and toxicity evidence. • Evacuation pre-warning delays had high consequences for survivability. • Pre-travel times and behaviors during incidents consistent with current methodology. • Low probability of entering irritant smoke had high consequence for outcomes. • Time to incapacitation can be derived from smoke:CO ratios for scenario validation. [ABSTRACT FROM AUTHOR]

The traditional methods to understand the development of elevated temperature in a structure, and also the associated structural response, are not representative of realistic fire scenarios. To provide a more accurate and realistic reflection of the fire development, the current paper develops a generic middleware which interfaces between the computational fluid dynamics (CFD) software Fire Dynamics Simulator (FDS) and the finite element (FE) analysis software OpenSees. This framework enables a fully integrated simulation of a realistic fire scenario including the heat transfer through the structure and the resulting thermo-mechanical response. The proposed framework is open-source and freely available and therefore can be used and further developed by researchers and practicing engineers and customised to their requirements. This paper shows validation against two sets of experimental results and one real fire incident. A number of different types of thermal boundary conditions such as gas temperatures and heat fluxes, are obtained from the CFD analysis and are then used in the subsequent heat transfer and thermo-mechanical analysis. The primary advantage of this computational tool is that it provides consultants and designers with the means to undertake large-scale projects requiring performance-based fire engineering solutions. • Open-source and free to distribute package for CFD-FEM software. • Validation against two experiments and one real fire incident. • A tool for performance-based design and fire investigation. [ABSTRACT FROM AUTHOR]

Char depth can be a useful measurement to help fire investigators in their work, but the conclusions that can be drawn from it are still debated. While its use to highlight fire spread patterns is usually recognised, there is no consensus on its further interpretation to determine heat exposure or fire duration. The present paper aims at investigating the relationship between char depth and cumulative exposure (heat flux density integral over the exposure duration, in [MJ/m2]). A cone calorimeter was used to expose samples of four wood species (oak, beech, fir, and particleboard) to controlled heat fluxes for varying durations. This proved that, for a given cumulative exposure, the measured char depths are comparable, even if this cumulative exposure is obtained in very different ways. This quantitative analysis (e.g. predicting the cumulative exposure based on a char depth measurement) is an important addition to the typical qualitative use of char depth measurements (i.e. the estimation of fire spread direction). Moreover, the layer of wood that might have burned away, which is often difficult to estimate in the field, could be easily related to the char depth, making this type of measurement even more useable by fire investigators. • Char depth is well described by the cumulative exposure (MJ/m2). • Square root relationships fit the data from this paper and the literature well. • Cumulative exposure can now be deduced from a char depth measurement, and vice versa. • Another simple fit could take into account the layer of wood that has burned away. [ABSTRACT FROM AUTHOR]

Coupled fire and evacuation computer simulations are used to numerically reconstruct a fatal fire that occurred in an indoor shooting range in Korea in 2009. Of the 16 occupants, 15 were killed and one survived. The analysis demonstrates that this approach can accurately reproduce the outcome of this fire. The approach is then used to forensically analyse the incident to identify factors significantly contributing to the high loss of life. In particular, occupant response times and flame spread rate over the polyurethane foam (PUF) cladded walls are investigated. The results suggest that it is unlikely that anyone could have survived if response times were greater than 5 s. Furthermore, it is suggested that fatalities couldn't have been avoided even if response times were zero. It is also demonstrated that gunpowder residue on the PUF walls is the critical factor in producing the high loss of life. The average number of fatalities could be reduced from 14.9 in the reconstruction case to 0.1 if the walls are completely free of gunpowder residue. However, to completely eliminate fire related casualties, it is necessary to use a PUF wall cladding material with low flame spread rates together with an effective gunpowder cleaning system. [ABSTRACT FROM AUTHOR]

There are several different preventive measures that can be used to reduce the number of fire fatalities in residential buildings, but information on how effective different measures are for different groups are, however, lacking. As a result, general measures are often implemented on large portions of the total population, which is not as cost-effective as targeting certain measures for certain groups in the population. Therefore, an analysis of fire statistics and data based on fire investigations reports is performed in this paper in order to provide recommendations for how different preventive measures can be targeted effectively. The studied population is divided into various groups based on the type of measures that are effective for each group, and it is seen that the effectiveness of different preventive measures are depending on age, gender, occupancy type, whether an individual is living alone and whether the individual is a smoker. The effectiveness of the different studied measured are presented in terms of fraction of fatalities averted and the benefit per implemented measure. The results presented in this paper is novel and can be used to motivate targeted interventions and for cost-benefit analyses. [ABSTRACT FROM AUTHOR]

Large open-plan compartment fires in modern buildings may exhibit a local burning region travelling across the floor plan as a 'travelling fire'. This phenomenon has been found in the forensic investigations of fire accidents and in the large compartment fire tests. The fire impact in a large compartment is spatially non-uniform and time-variant, which can cause severe local damage to structural components. Advanced from the previous models assuming constant travelling, the natural fire model established in this paper comprises time-variant and test-based travelling behaviour models and localised fire models of various modes. It is demonstrated with the fast-spread Veselí fire test and the slow-spread Malveira fire test. A generic structural model is set up within OpenSees for fire to examine the thermal impact on structural members under various travelling fire scenarios of different travelling parameters, fire travelling directions, and beam sizes. Locally much higher thermal responses are represented after introducing behaviour models while adopting the same design fire load. Based on the work in this paper, a library of design fire models can be potentially enabled to examine the fire safety performance of structures regarding the realistic fire load and fire impact aiming for discovering unknown worse fire scenarios. • Time-variant travelling behaviour models are proposed for large compartment fire scenarios with transitions of fire modes. • The travelling behaviour models are demonstrated with a fast-spread fire and a slow-spread fire. • The thermal responses of the steel beam are dominated by the "stay time" and intensity of the near field. • By introducing travelling behaviour models, design fire scenarios of locally high fire impact can be found. [ABSTRACT FROM AUTHOR]

Abstract: Fire scene investigation relies on in situ investigation (observations that take place where the fire occurred) and laboratory analysis. Nowadays the role and place of fire modelling in fire forensic investigation are debated within the forensic community. The main objective of this work is to propose a methodology to consider the stochastic aspect of fire development in a specific case by using fire modelling. Therefore, a stochastic fire safety engineering tool so-called SCHEMA-SI (Stochastic Computation and Hybrid Event Modelling Approach-Sécurité Incendie) developed at the CSTB (French Scientific and Technical Construction Centre) has been used to reconstruct a fire scene that occurred in 2007 in a senior care facility situated in the Paris suburb (France). In this case study, several fire scenarios were generated with SCHEMA-SI from probabilistic data in order to perform fire scene investigation. Each scenario is composed on one hand by a succession of dated events and on the other hand by physical quantities time-evolution at different locations in the building (heat release rate, temperature, interface height…). The objective of this work was to find the scenarios which allow getting an acceptable agreement between the calculated values and the observations from the real situation in the fire scene. Among the thousands of fire scenarios generated, 20% were compliant with the fire scene observations. The analysis of these compliant scenarios gave a better idea of what might have happened in the care facility. At the end, the contribution of numerical simulation in a fire scene analysis is discussed. [Copyright &y& Elsevier]

Abstract: An important cause of fire departure in industrial facilities is due to electrical origin and particularly to electrical cabinets. The investigation of such fires has been scarce up to now and has been investigated exclusively in the nuclear industry. The Institut de Radioprotection et de Sûreté Nucléaire (IRSN) conducted a large number of experiments involving electrical cabinets burning either under a calorimetric hood or inside a mechanically ventilated compartment to investigate this topic. Calorimetric hood experiments demonstrated that the most important parameter is the size of the vents of the cabinet and that the time to flashover depends on many factors and seems somewhat random with regard to the observable parameters. The influence of the compartment on the fire behavior depends on the temperature of the surrounding atmosphere of the cabinet and on the oxygen content in the compartment at the level of the inlet vent of the cabinet. The compartment strongly impacts the pyrolysis of the combustible, affecting the fire duration, but has a weak effect on the Heat Release Rate (HRR). Experiments were usually remarkably reproducible, opening the way to a phenomenological description of this type of fire. A semi-empirical model based on the coupled solution of ventilation limit and excess pyrolysate could then be developed. This model was introduced in a zone code, and an ad-hoc modeling of the fire extinction based on a critical surfacic mass loss rate is proposed. The major features of the compartment fire experiments such as characteristic HRR and fire duration could then be reproduced with acceptable error. The development of such a semi-empirical model is a common practice in fire safety engineering concerned with complex combustibles. [Copyright &y& Elsevier]

Abstract: Four full-scale fire experiments using 4-door sedan passenger cars were carried out. The cars were ignited either at the splashguard of the right rear wheel or at the left front seat in the passenger compartment with a gasoline spill. The temperature inside the burning car and the mass loss rate were measured. The burning of the 4-door sedan was composed of three compartmental fires: the engine compartment, the passenger compartment, and the rear part inclusive of the fuel. In the experiments where ignition was initiated at the splashguard, the flame spread in the following order: to the rear part of the car, to the passenger compartment, and to the engine compartment. Breakage of the window glass markedly affected the spread of fire into the passenger compartment. The quantity of gasoline in the fuel tank also affected the speed of spread of the fire, because the gasoline ignited at an early stage of the fire. In the experiment where ignition was initiated in the passenger compartment, the fire gained force after the windshield was broken entirely. The flame spread in the following order: to the passenger compartment, to the engine compartment, and to the rear part of the car. The temperature within the passenger compartment peaked at 1000°C. The heat release rate (HRR) curves showed several peaks depending on the burning of the three compartments. The HRR increased markedly when the fire spread to several different parts of the car at the same time. The HHR peaked at 3MW when the passenger compartment and fuel (gasoline) burned simultaneously. The measured HRR curves were characterized by superposition of a Boltzmann curve and a Gaussian curve in order to obtain a model, which allowed us to make a more precise prediction of the fire spread probability from a burning car to nearby structures. The HRRs of burning cars were described by the sum of HRR from each compartment. [Copyright &y& Elsevier]

Abstract: This paper investigates the structural behaviour of unbonded post-tensioned one-way spanning concrete slabs in fire conditions. The slabs were simply supported and reinforced with 15.7mm nominal diameter seven-wire mono-strand tendons. A nonlinear finite element model for the analysis of post-tensioned unbonded concrete slabs at elevated temperatures was developed. The mechanical and thermal material nonlinearities of the concrete, prestressing tendon and anchorages have been carefully inserted into the model. The interface between the tendon and surrounding concrete was also modelled, allowing the tendon to retain its profile shape during the deformation of the slab. The temperature distribution throughout the slab, time–deflection behaviour, time–longitudinal expansion, time–stress behaviour in the tendon, and the failure modes were predicted by the model and verified against test data. The study has shown that the coefficients of thermal expansion currently used in the European Code for calcareous and siliceous concrete can lead to inaccurate predictions of the structural behaviour. A parametric study was conducted to investigate the effects on the global structural behaviour due to the change in the aggregate type, load ratio and boundary conditions. It was shown that by varying the boundary conditions the fire resistance was greatly affected. Although changing the aggregate type and load ratio affected the time-displacement response, the fire resistance defined by failure of the slab was not affected due to the splitting mode of failure above the tendon locations not being affected by these parameters. Comparison with the codes shows that the UK code BS8110 is generally unconservative, whereas the Eurocode EN1992-1-2 provides reasonable design rules. [Copyright &y& Elsevier]

Wildland fires present a threat to both the environment and to homes and businesses in the wildland urban interface. Understanding the behavior of wildland fires is crucial for developing informed risk management techniques, such as prescribed burning, to prevent uncontrolled fires, which devastate communities globally. In this work, an optically accessible facility was developed combining traditional and optical diagnostic techniques to study the combustion of wildland fuels. This facility was then used to study the burning characteristics of loblolly pine needles (Pinus taeda). Mass loss rate, flame temperature, propagation rate, flame geometry, and OH* chemiluminescent flame intensity were measured for fuel loadings of 0.98, 1.31, and 1.63 kg/m2. Mass loss rate increased linearly with fuel loading. The flame propagation rate increased slightly with fuel loading while approaching an asymptotic value. The flame height and surface area increased more significantly with fuel loading, but also approached asymptotic values. Flame depth increased slightly with fuel loading, and throughout the duration of the test. The flame intensity and flame temperature did not change significantly with fuel loading. • Developed an optically accessible, intermediate-scale experimental facility. • The burning characteristics of loblolly pine straw were studied. • Both traditional and modern optical diagnostic techniques were used. • Increasing fuel loading results in a proportional increase in mass loss rate. • Mass loss rate estimates from optical data correlate well with load cell data. [ABSTRACT FROM AUTHOR]

Controlled gas burner experiments were conducted in single- and two-story residential style structures instrumented with pressure transducers, thermocouples, and bi-directional probes throughout the structures. Exterior doors and window openings were vented in a controlled sequence to investigate the effect of the resulting flow paths on fire-induced flow dynamics and thermal conditions in the structures. The data collected in these experiments provides validation cases for the fire modeling community which currently lacks full-scale data from experiments in realistic residential style structures. The Fire Dynamics Simulator was used to model each scenario in a validation exercise that also investigated the sensitivity of the pressure predictions to the model parameters. The model was capable of predicting the qualitative changes in pressure measurements due to ventilation events as well as the apparent elevation of the neutral plane. Peak pressures were predicted to within 6% on average and quasi-steady static pressures were predicted to within 24% on average. The mean instantaneous error between the experimental pressures and those predicted with the "Localized Leakage" method was approximately 53% compared to 67% with the "Pressure Zone Leakage" method prior to the first ventilation event. • FDS pressure predictions are sensitive to leakage definition in sealed structures. • The "Localized Leakage" method is more accurate prior to structure ventilation. • FDS temperature and velocity predictions are insensitive to leakage definition. [ABSTRACT FROM AUTHOR]

Abstract: Experimental studies on charring of wood are reviewed with the objective of providing guidance for interpretation of char patterns in fire investigations. It is shown that in room fires, the charring rate of wood members that do not have gaps or joints is similar in magnitude to values obtained from fire-resistance tests. But floors and other assemblies having joints that are not solidly glue-laminated char through much more rapidly. Especially rapid charring rates in floor constructions imply high heat fluxes and good ventilation—they are not an indicator that liquid accelerants were used. Fires started with a liquid fuel that do not lead to widespread involvement of other combustibles within the room leave easily recognized burn patterns. [Copyright &y& Elsevier]

London Fire Brigade''s real fire library is a database of information collected from real fire incidents by specialist teams of experienced fire investigators operating in the Greater London Area. A sample of this data collected over a five-year period has been used to characterise the distributions of fire sizes, fire growth rates and times between events that occur in building fires in a form suitable for use with probabilistic risk assessment. The effect of occupancy type, ignition source, first material ignited, and first aid fire-fighting by the occupants on the form of these distributions was then examined. Incidents that produced very large losses, rapid growth rates and extended time delays were also analysed to try to determine the reasons why such extremes occur in real fires. [Copyright &y& Elsevier]

To improve on the performance of traditional ship fire alarm systems, this paper investigates a dual-sensor device employing a grey-fuzzy algorithm. The theoretical aspects of the device and its experimental evaluation are presented. In terms of the algorithm, first an adaptive fuzzy classification system with an automatically generated rule base is developed for accurate fire-detection response to the output of a sensor pair (one temperature K-type thermocouple and one analog photoelectric smoke detector). Second, two alternative grey GM(1,1) prediction models are developed for anticipating trends in real-time temperature and smoke data, thus allowing early fire warning. Finally, the fuzzy system is combined with the grey-prediction algorithms for final testing. In the engine room of a docked coastal fishing trawler, two experimentally controlled fires are created, one open flame and one smoldering, and results from the sensor pair are recorded. As-detected results for each fire are processed by computer which tests the response behaviour of the alternative fuzzy-grey options and selects the optimal options set, and also compares the dual-sensor pair as conventionally operated in a commercial detector. Results indicate grey-fuzzy algorithms combining fuzzy rule-based classification and grey GM(1,1) unified-dimensional new message modelling are feasible in real-time shipboard fire detection, allowing accurate fire alarm triggering from 30 to 60 s earlier than conventional methodology. [Copyright &y& Elsevier]

London is a large capital city with a population of approximately seven million people. It shares many problems with other large cities around the world, including deaths due to fire. Many of these fire deaths can be linked to social problems such as poor housing, loneliness, illness, etc.Data from the London Fire Brigade Real Fire Library—a unique database of information collected from real fire incidents by dedicated teams of fire investigators operating in the Greater London Area has been used to obtain a range of statistics about fatal fires and fire death victims for the 5-year period from 1996 to 2000. Most deaths occurred in unintentional dwelling fires. The statistical information has therefore been analysed to identify the main factors involved as to why people die in unintentional dwelling fires and see what lessons can be learnt from these deaths.Common risk factors identified in the unintentional dwelling fire deaths investigated include smoking, alcohol, old age, disability, illness, living alone, social deprivation and not having a working smoke alarm fitted. Comparisons are also made with the results found from other studies and measures for preventing unintentional dwelling fire deaths are examined. [Copyright &y& Elsevier]

In most places where a fire started, electric molten marks that may be the cause of the fire are found. Various methods have been studied for identifying these electric molten marks to be either the cause of a fire (a primary molten mark (PMM)) or one caused by the flames of the fire (a secondary molten mark (SMM)). Little was studied, however, on their identification using the carbonized residue remaining in the molten marks.In this study, therefore, it was examined whether it was possible to discriminate between the PMMs and SMMs by analyzing the crystal structure of the carbon in the carbonized residue, which came from PVC insulation, remaining in the primary and the SMMs.As a result, it has been found that PMMs contain both graphitized carbon and amorphous carbon, whereas SMMs only contain amorphous carbon. [Copyright &y& Elsevier]

In recent years, there has been a growing number of projects on informal settlement (IS) fire research, which has been primarily focused on understanding the fire dynamics in IS through full-scale experiments. However, much less is known about real IS fire incidents. Recently, a Framework for Fire Investigations in Informal Settlements (FFIIS) was developed. However, the FFIIS has not been applied to real IS fire incidents yet. This paper seeks to conduct fire investigations by applying the FFIIS to three real fire events. One of them was recorded by a CCTV camera and was analysed in depth in previous work. The video footage was used to benchmark the findings obtain using the FFIIS. The application of the FFIIS allows one to develop hypotheses that more accurately define the area of fire origin and pattern formation sequence. This implies that the fire pattern for large post-flashover fires in ISs can be treated as wildland fires pattern, as proposed by the FFIIS. Additionally, spread rates and the impact of dwellings' separation distances, in these incidents, are studied. Understanding the limitations and the quality of the information that can be obtained when applying the FFIIS is fundamental to improve the guidelines proposed. • A Framework for fire investigations in informal settlement was applied to real fires. • It is the first time that a well-define framework is applied to informal settlement. • The recording of one of the selected fires was used to benchmark the findings. • Hypotheses for the fire origin and pattern formation sequence were developed. • Additionally, fire spread rates and the reasons for home survival were studied. [ABSTRACT FROM AUTHOR]

This paper presents the experimental findings on fire resistance of concrete encased steel (CES) composite columns made of C120 concrete and S500/S690 high-strength steel section. Eight full-scale CES columns were tested under concentrated load and heated under the ISO834 fire until failure. The fire performance of each CES column specimen was evaluated by analysing the fire resistance time, axial displacement-time curve, temperature-time curve, rotational angle of end support, post-fire conditions of the concrete surface and failure mode. The experimental study showed that the addition of polypropylene fibre was effective in minimizing explosive concrete spalling in high-strength CES columns to achieve comparable fire resistance time as those of normal-strength CES columns. A database containing 40 CES specimens was established to assess the accuracy of the current design methods in predicting the fire resistance of CES columns. The limitations of each design method were discussed based on whether they can provide safe and accurate predictions of the fire resistance of tested CES column specimens. Finally, recommendations were provided to modify the current methods for fire resistant design of CES columns made of high-strength concrete. • ISO834 fire tests were carried out on eight high-strength concrete encased steel columns. • Steel contribution ratio affects the fire resistance of CES columns. • A database containing 40 fire-tested CES columns is established. • Current design methods overestimate the fire resistance for some tested specimens. • Design methods in EN1994-1-2 can be extended for high-strength CES columns. [ABSTRACT FROM AUTHOR]

Investigation of fires are useful tools for gathering experience and knowledge of how and why fires occur and why they develop as they do. Several tools for accident investigation that also are applicable for analysis of fires are available. Data from fires is valuable for different branches of the fire safety science and are also used in revisions of fire regulations. This paper describes the concept of accident investigation with focus on learning and presents how investigation from fires has been used as a valuable tool in Norwegian fire safety management. Examples of how learnings have improved the residential fire safety level in Norway over the last decades are described. Three different analyses of fatal fires over four decades have given knowledge about how and why residential fires start, and how the victims could be characterized. The fire fatality rate in Norway has decreased by 50% from 1970 until 2014, one of the reasons for this is believed to be implementation of several targeted fire safety measures over the years. Through fire investigations combined with research, new trends in society and their possible implications on fire safety can be uncovered and lead to a more proactive fire safety management. • Fire accidents are useful case studies for many disciplines in fire safety science. • Investigation results have led to important revisions of fire safety regulations. • Learning from investigations have increased the fire safety level in Norway. • Learning from previous fires will also increase the awareness of new fire risks. [ABSTRACT FROM AUTHOR]

Informal settlements regularly experience small and large fires. In South Africa, there were 5940 informal settlement fires during 2017, which is approximately 16 per day. Currently, post-fire investigations are often not being conducted, and close to 40% of all fire causes in informal settlements are labelled as "undetermined". Conducting post-fire investigations can provide important information to develop better evidence-based responses for improving fire safety in these communities. It is acknowledged that due to the inherent nature of informal settlements high levels of certainty in fire-cause determination are often not possible. After ignition, the onset of flashover occurs rapidly, thus most structures are destroyed within minutes, and often multiple dwellings are involved in a single incident. This paper seeks to apply well-known forensic fire investigation principles (primarily using NFPA 921), to informal settlements to develop a framework and guidelines, in order to (a) identify the fire origin and the fire cause, (b) obtain data on human behaviour in fire, (c) understand the fire spread sequence, and (d) evaluate the effectiveness of suppression and response efforts. The proposed methodology was used to analyse the Imizamo Yethu fire that occurred in 2017. Additionally, the work highlights the challenges associated with conducting such investigations. [ABSTRACT FROM AUTHOR]

In addition to classical compartment fire development stages, smoke explosion s can occur for underventilated conditions while the ventilation openings remain the same. Smoke explosions are different from backdrafts, involving changes in ventilation by additional openings. In this study, the burning history of medium-density fibre (MDF) cribs located at three different elevations has been investigated for the first time in an underventilated enclosure having two vertical openings at the front wall. The effects are examined of different fuel locations, the crib geometry and the ventilation on the mass loss and heat release rates. The fuel mass loss and heat release rates being nearly independent of the crib location and type depend on a new ventilation parameter determined from the distance between the two openings in a simplified way including effects of mass pyrolysis rate and gas temperatures. The mass air inflow is also proportional to this ventilation parameter and independent of the gas temperatures. In some experiments, however, the fires produced single or multiple smoke explosions after a dip in the heat release rate ejecting flames outside. The occurrence of a smoke explosion in relation to the porosity of crib, appearance of smouldering and the vitiated environment is also discussed. [ABSTRACT FROM AUTHOR]

Façade systems play an important role in fire compartmentation of a building and reducing the likelihood of fire spreading through and outside of the building walls. The use of sprinklers in building regulations often allows for smaller building separation. However, no additional benefits are usually given to additional internal sprinkler protection of the external glass façade using standard pendant sprinklers. Four compartment fire experiments were performed with non-fire-rated aluminium façades with two- and three-layered Insulating Glass Units (IGU), protected by pendant-type sprinklers (DN15, K-factor = 80, T = 68 °C). Sprinklers were in row 14–55 cm from the glazing, with 1.514–1.83 m separation distance. In all experiments, façades achieved satisfactory performance in terms of glazing integrity, insulation and reducing the thermal radiation. Under a non-uniform water distribution, parts of the glass were dry (1.7%–15.7% of IGU area), where we have observed soot deposition and local damage to fire exposed glass layer, but no loss of the structural integrity. The temperatures on the unexposed side did not exceed 86 °C, the peak measured temperature of the internal glass surface was 173 °C. The performed experiments confirmed the capability of standard pendant-type sprinklers to enhance the fire protection features of a building façade. Image 1 • Four large scale compartment fire experiments were performed. • Sprinklers may substantially improve the fire performance of building façade. • Non-uniform heat transfer through glass did not lead to loss of structural integrity. • Sprinklers efficiently cool the thermal plume from ventilation windows. • External thermal radiation from fire is shut out by the sprinklers. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the far-field radiation properties of modelled gaseous pool fires in cross winds, which have not been previously discussed in the literature. Bench scale experiments were conducted to quantify the evolution of radiation emission of pool fires using square porous burners (stainless-steel boxes filled with quartz sand) of different sizes (8, 10, 15 and 20 cm), employing propane as the fuel. The radiation heat flux as well as the radiation fraction were measured by a single-point method. For all pool fires employed, it was found that the radiation heat flux, as well as the radiation fraction, declined with increasing wind speed from ~0.5 m/s up to ~5 m/s. Based on an assumed triangular geometric approximation of flame projection area of wind-blown pool fires, a simplified correlation related to the flame surface area exposed to the radiometer was proposed to interpret the changing radiation fraction of pool fires of different sizes and heat release rates (HRR) in cross winds. The proposed function correlates the experimental data well under relative strong wind conditions (Fr > 1). This work provides new basic data revealing the radiation evolution behaviour of gaseous pool fires with respect to wind speed. • Far field radiation properties of gaseous modelled wind-blown pool fires. • Flame radiation fraction quantified for various pool fire sizes, HRRs and wind speeds. • A proposed triangular geometric approximation of wind-blown pool fires. • Proposed function correlates data well under relative strong wind conditions. [ABSTRACT FROM AUTHOR]

The study presented herein describes an exploratory investigation on the fire performance of intumescent coatings used on timber elements. Timber samples, uncoated or coated with three different thicknesses of a commercially available thin intumescent coating, were tested using high-performance radiant panels according to the H-TRIS fire test method. Test samples were heated for 60 min at a constant incident radiant heat flux of 50 kW/m2. Uncoated samples quickly ignited, while coated samples showed good adherence between the intumescent coating and the timber substrate and limited flaming. At the start of the heating exposure, the intumescent coating rapidly swelled up to a quasi-steady thickness. The presence of the intumescent coating at the exposed surface of timber samples seemed to delay the onset of timber charring and also to reduce the average charring rate after initiation of charring. The delay is proportional to the DFT of the intumescent coating, up to 40 min from the start of heating for a DFT of 2.1 mm (based on 300 °C isotherm). The experimental results described herein showed that thin intumescent coatings may be effectively used on timber for delaying the onset of charring and assuming a reduced timber charring rate during heating. [ABSTRACT FROM AUTHOR]