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The aim of the research is to determine changes in the composition of selected gasoline compounds in cotton carpet samples due to different weathering times. EVO 95 gasoline was used as a fire accelerant and a cotton carpet was used as a matrix. The samples were exposed to various weathering durations (0–360 min) in laboratory conditions. We investigated samples that were unburnt (only weathered) and samples that were burned and subsequently subjected to further weathering. Residual gasoline compounds in carpet samples were determined by gas phase extraction (headspace – HS) coupled with gas chromatography (GC) and mass spectrometry (MS). We focused on the comparison of selected gasoline compounds; toluene, ethylbenzene, p-xylene, 1,2,3-trimethylbenzene (TMB), 1,3,5-trimethylbenzene and naphthalene. The biggest changes were determined in the reduction of the intensity of most volatile compounds (alkylalkanes), where toluene decreased by 11.92%. A similar but not so pronounced trend, occurred in the burned samples, where toluene decreased by 7.40%. Minor changes occurred in alkyl derivatives of benzene, where some of the total 15 gasoline markers also occur, e.g. (1,2,3-trimethylbenzene, 1,3,5-trimethylbenzene). On the contrary, naphthalene as a heavier compound showed an increase in intensity about 0.42%. For burnt samples, the increase was 1.31%. The results show that largest changes can be observed after four or five hours of weathering, which implies the need for rapid sampling and subsequent timely analysis. [ABSTRACT FROM AUTHOR]

Anthropological assessment of a scene for fatal fire victims can prove crucial in the search, recovery and identification of human remains from fire‐related death investigations. On scene contributions of the anthropologist include, but are not limited to, searching for remains in burnt structures, vehicles, roadside dumps, campfire accidents, and other fire investigations, as well as the proper documentation and collection of remains. While patterning and sequencing for all fire events is not standardized, thermal alteration can be classified and consistent terminology can be used to reflect commonalities and evaluation of thermally altered remains. Further, the anthropologist has the ability to evaluate damage to the remains in terms of possible associated trauma (e.g., antemortem, postmortem). However, scene investigators do not regularly call upon anthropologists to assist at the scene and often do not know the contributions and benefits of having an anthropologist on scene. This perspective article focuses on the development of fatal fire investigations within the United States, key terminology, and core concepts within anthropological sciences and provides recommendations for how fire investigators and anthropologists can collaborate–bridging the gap between the two fields. Uniting literature from fire science, anthropology, and fire investigations, this overview underscores the importance of anthropology and fire investigator collaboration. This article is categorized under:Forensic Anthropology > Taphonomic Changes and the EnvironmentForensic Anthropology > Trauma AnalysisForensic Anthropology > Anthropology in Mass Disaster & War Crime Contexts [ABSTRACT FROM AUTHOR]

The background and current studies in the area of fire investigation at the Turin Fire Department's Forensic Laboratory. It is uncommon to find an investigation facility, and even less often within fire brigade headquarters, that uses GC-MS and GC-TOF extensively to look for accelerants. During 16 years of intense effort, the Turin Fire Department in Italy accomplished various research projects on the identification of flame accelerants and more in fire residues. This collaborative effort between academics and firefighters is unique. It is based on the perspectives of individuals who often fight fires before going on to investigation. The article will outline the study that was done, explain how advances in instrumentation have produced ever-better outcomes and the next steps in the foreseeable future. [ABSTRACT FROM AUTHOR]

Electrical fires perennially rank first in fire occurrence types, with conductor overcurrent being one of the main inducements. This topic draws significant attention from scientific researchers and fire investigators. To understand the overcurrent fault and combustion characteristics of copper‐clad aluminum conductors, this paper examines 2.5 mm2 copper‐clad aluminum conductors that meet national standards, investigating morphological changes, temperature variations in the core and insulation layer, and flame propagation patterns under overcurrent conditions. Experiments using an electrical fault simulation device were conducted to study overcurrent failures of copper‐clad aluminum conductors under 52.5–105 A conditions. The results indicate that when the current exceeds 67.5 A, the conductor undergoes a series of changes during energization, including smoking, expanding, carbonizing, burning, and breaking; at 52.5 A, the insulation layer reaches thermal equilibrium at 150 s without combustion; for currents between 60–67.5 A, wire core temperature variations can be divided into three stages; at 75 A, the insulation layer reaches thermal equilibrium 10s before breaking; currents above 82.5 A see a sharp increase in temperature in both the core and insulation layer before the conductor breaks; above 97.5 A, the conductor first breaks and then burns. The research results have significant theoretical value in improving the scientific rigor of fire accident investigations and forensic evidence examinations. [ABSTRACT FROM AUTHOR]

The effect of fire source location (FSL) on compartment fire phenomena with a single natural ceiling vent was experimentally investigated under various vent area (VA) and heat release rate (HRR) conditions. Two FSL cases, where the fire source was located at the centre (FSLC) and on the side (FSLS) of the floor, were tested. In the bidirectional vent flow patterns of FSLC and FSLS, the detailed locations where the smoke outflow and the fresh air inflow occurred were different. Empirical correlations were proposed for predicting the smoke outflow areas. FSLC exhibited a higher central velocity of the outflow, larger estimated mass flow rate of the outflow, and lower temperatures inside the compartment than FSLS. The estimated mass flow rate of the outflow depended more on VA than on HRR. A previous correlation was more suitable for FSLS than FSLC in predicting the mass flow rate of the outflow. [ABSTRACT FROM AUTHOR]

Magnesium is a combustible metal that poses various safety risks, including fires and explosions. However, there are limited safety measures available to prevent and respond to potential fires and explosion incidents in the metal industry. In this study, the combustion process of Mg fires was closely examined using infrared thermal imaging, focusing on the effects of Mg powder size. For the experiment, Mg powder was burned by increasing the temperature to approximately 967.4 K using an ignition unit and controller equipped with a tungsten heater. Moreover, combustion velocity measurement experiments for Mg particle sizes of 75, 100, and 150 μm were conducted using the combustion velocity measurement device presented in the NFPA 484 standard. On combustion of Mg, flames are observed; smoke is emitted as demonstrated by thermal and flow visualization experiments. The combustion velocity measurement experiment results demonstrated that the greater the slope value (combustion velocity) for the combustion length over time, the faster is the combustion velocity, with the 75 μm particle size having the fastest combustion velocity. The results of this experiment can be utilized as references for Mg fire control design and to gain a better understanding of the scope of smoke and fire hazard investigation measures. [ABSTRACT FROM AUTHOR]

This study investigated the possibility of extending the soot morphology analyses to acoustically agglomerated soot deposited on the surface of smoke alarms and of applying the validity of soot analysis for unique chemical signatures in the field of fire investigations. Through collecting soot samples, including agglomerated soot acquired from smoke alarms, this research presents a pioneering stride in soot morphology data analyses conducted by leveraging advanced deep learning methodologies. Preliminary outcomes underline that the proposed convolutional neural network model has the potential to decode intricate soot characteristics and to distinguish soot particle images between diverse fuel types and burning conditions. In particular, for the acoustically agglomerated soot collected by smoke alarms, it was also found possible to decode their intricate morphology by applying the proposed data-driven approach. [ABSTRACT FROM AUTHOR]

The characteristics of the vegetation fire (VF) regime are strongly influenced by geographical variables such as regional physiographic settings, location, and climate. Understanding the VF regime is extremely important for managing and mitigating the impacts of fires on ecosystems, communities, and human activities in forest fire-prone regions. The present study thereby aimed to explore the potential effects of the confounding factors on VF in India to offer actionable and achievable solutions for mitigating this concurring environmental issue sustainably. A global burn area (250 m) data (Fire-CCIv5.1) and fire radiative power (FRP) were used to investigate the dynamics of VF across seven different divisions in India. The study also used the maximum and minimum temperatures, precipitation, population density, and intensity of human modification to model forest burn areas (including grassland). The Coupled Model Intercomparison Project-6 (CMIP6) was used to predict the burn area for 2030 and 2050 future climate scenarios. The present study accounted for a sizable increasing trend of VF during 2001–2019 period. The highest increasing trend was found in central India (513 and 343 km2 year−1 in the forest and crop fire, respectively), followed by southern India (364 km2 year−1 in forest fire), and upper Indo-Gangetic plain (128 km2 year−1 in crop fire). The FRP has varied significantly across the divisions, with the north-eastern Himalayas exhibiting the highest FRP hotspot. The maximum and minimum temperatures have the greatest influence on forest fires, according to Random Forest (RF) modeling. The estimated pre-monsoonal burn area for 2050 and 2050 future scenarios suggested a more frequent forest fire occurrence across India, particularly in southern and central India. A comprehensive forest fire control policy is therefore essential to safeguard and conserve forest cover in the regions, affected by forest fire periodically. [ABSTRACT FROM AUTHOR]

The frequent occurrence of thermal runaway accidents of lithium-ion batteries has seriously hindered their large-scale application in new energy vehicles and energy storage power plants. Careful analysis of lithium-ion batteries can essentially determine the cause of the accident and then reduce the likelihood of lithium-ion battery thermal runaway accidents. However, there are few current studies on lithium-ion battery accident investigation, and the destruction of traces due to the violent reaction of the battery's thermal runaway increases the difficulty of battery accident investigation. The thermal runaway accident scenarios of lithium-ion batteries with different states of charge will show different regular characteristics of the thermal runaway properties and trace characteristics of lithium-ion batteries. Establishing the relationship between the thermal runaway characteristics of lithium-ion batteries, the trace law and the state of charge can effectively improve the technology of in-depth battery accident investigation. This study investigated the thermal runaway and trace characteristics of lithium-ion batteries triggered by nail penetrating at different states of charge using 8 Ah soft pack lithium iron phosphate batteries as the research object. The results show that lithium iron phosphate Li-ion batteries do not trigger thermal runaway under nail penetrating conditions when the state of charge is less than 20%, with no obvious phenomena and slight changes in the voltage and surface temperature of the battery, with the temperature only rising by 5 ℃. Both the 60% and 100% SOC LiFePO4 batteries underwent thermal runaway within a few seconds after the needle puncture and produced a large amount of white smoke, with the voltage rapidly dropping to 0 V and the maximum temperature on the front of the battery reached 93 ℃ and 125 ℃, respectively, and the rate of temperature rise was significantly higher in the latter than in the former, with both reaching temperatures above 200 ℃ at the penetration point and higher than at the entry point, while the 100% SOC battery showed electrical sparks and more smoke after the puncture due to a more violent internal short-circuit. The state of charge affects the cracks and particle spacing on the surface of the anode electrode and the smoothness of the surface. The results of this paper provide ideas for qualitative and quantitative analysis of lithium-ion battery accident causation, which can provide guidance for effectively improving the ability to investigate lithium-ion battery accidents. [ABSTRACT FROM AUTHOR]

Historic timber structures face substantial fire loads and complex fire risks. Subsequent renovations and utilization may influence their fire safety performance. Therefore, accurately predicting indoor fire development in historic buildings and assessing their fire safety performance is crucial. Numerical fire simulation is currently at the forefront of analyzing and assessing fire risks in historic buildings. However, there is a shortage of globally accessible historic building fire data. This paper proposes a method to determine fire scenarios, peak heat release rates, and development curves of indoor fires in wooden historic buildings through a fire load investigation. Using the Guangzhou ancestral hall as an example, PyroSim fire dynamics simulation software is employed to calculate fire development and assess the available safe evacuation time. The simulation results are subsequently input into the Pathfinder evacuation simulation software to ascertain the required safe evacuation time for indoor occupants. A comparative assessment is conducted to evaluate the fire safety performance before and after the renovation of historic buildings. The research findings indicate that installing closed glass curtain walls in the courtyards of ancestral hall buildings in Guangzhou accelerates the infiltration of smoke during fires, leading to rapid fire spread and long-distance ignition, significantly reducing the time available for safe evacuation. Therefore, when renovating and utilizing the ancestral hall buildings in Guangzhou, the installation of ventilation and smoke extraction systems should be prioritized to slow down fire development. Additionally, controlling the number of indoor occupants is an effective management measure to mitigate fire damage in historic buildings. [ABSTRACT FROM AUTHOR]

Featured Application: Machine learning in forensic science and the use of MATLAB for identification and classification of petrol source. Petrol is considered the most common fire accelerant. However, the identification and classification of petrol sources through the years has proven to be a challenging field in the investigation of fire debris analysis. This research explored the possibility of identifying petrol sources by high-field NMR methods accompanied by ML (machine learning). The automated identification and classification of petrol brands were achieved for first time based on the ML classification model developed in this research. A hierarchical classification model was constructed using local classifiers to categorize neat or weathered petrol into its sources. [ABSTRACT FROM AUTHOR]

Nowadays, the damaging effects on humanity, such as extreme weather caused by climate change, the pandemic-induced isolation, or the drastic increase in the cost of energy carriers, etc., have led to the need to change the design of our buildings. The need to design buildings for safety, prevention and sustainability requires a change in our design thinking. The damaging effects of these extremes all have an impact on the fire safety situation of a building. The conclusions of fire investigation procedures suggest that a disorderly state of the built environment typically develops prior to fire starts. As stated above, the researchers are investigating the degree of orderliness in the research, for which they are using network science methods. Based on the hypothesis, tidiness is also an aesthetic value, whose high level of appearance determines the appropriate fire safety situation. The high aesthetic value of architectural fire protection correlates with the degree of orderliness, i.e. it is a significant determinant of the long-term sustainable stable fire safety situation of a building. [ABSTRACT FROM AUTHOR]

The post-fire assessment of concrete structures is a complex task that requires the integration of multiple measurements from different techniques. The current approach to integrate information from different sources relies mainly on expert judgement, meaning that no explicit consideration is given to the precision of different techniques. This paper presents a Bayesian updating methodology that integrates information from different sources about the maximum temperature the concrete experienced during fire exposure at a certain depth, such as discoloration and rebound hammer measurements, by considering the uncertainties and errors associated with measurements. The data is then used to update the prior information on the uncertain parameters of interest, here the fire load density and opening factor. These updated distributions provide a better estimate of the fire exposure, thermal and damage gradient and the residual condition of the structure. The proof-of-concept and effectiveness of the proposed methodology are demonstrated through a case study. The results show that the proposed methodology is able to effectively incorporate the uncertainties and errors associated with the assessment techniques, producing more reliable estimates of the fire severity. This method has the potential to improve the post-fire assessment process and provide more accurate information for the rehabilitation of concrete structures. [ABSTRACT FROM AUTHOR]

In 2005, a line-of-duty death of an instructor at a firefighter training facility spawned research into both firefighter training and improving firefighter protective gear. Since the incident, there has been additional research into the material properties, firefighter facepiece performance, and the classification of firefighter exposures. This has been in parallel to significant improvements in the ability to model fires and predict, rather than prescribe, fire growth. As this recent body of work was not available at the time of incident investigation, the incident was revisited using the current version of Fire Dynamics Simulator. The full day of training evolutions was modeled in Fire Dynamics Simulator using recent data on wood pyrolysis (the fuel) and facepiece reaction to heat. Fire Dynamics Simulator results were evaluated against the testing done following the incident. Facepiece research was used to develop hole formation criteria that could be evaluated from Fire Dynamics Simulator predictions of facepiece exposure. This was used to compare the performance of facepieces contemporary with the incident to today's facepieces. In addition, exposure predictions were evaluated in the context of exposure hazard categories developed for firefighter protective gear. [ABSTRACT FROM AUTHOR]

The study was undertaken to assess the province of Marinduque's fire incidence from 2018 to 2022 and determine its firefighting capability, which includes fire prevention programs, tools, PPEs and Equipment (fire trucks), manpower, skills and trainings acquired, facilities and infrastructure and financial resources management. Present the level of performance in implementing fire prevention programs, and to know if there is a significant relationship of firefighting capabilities and performance of BFP-Marinduque Personnel. To identify the gaps in the implementation of fire prevention programs as well as the problems encountered and strategies employed by the personnel and management of the Bureau of Fire Protection in the province of Marinduque from 2018 to 2022. Further, to propose a framework of service delivery for fire prevention based from the results of this study that could be helpful in the future researches. The descriptive research method was used in this study. The documentation records obtained from the Bureau of Fire Protection Provincial Office in Tampus, Boac, Marinduque, and the province's six Municipal Fire Stations, as well as the survey questionnaires administered in each station and the provincial office, are the sources of data. The information was tallied, analyzed and interpreted. The statistical tools that were utilized to treat and interpret the data required for the study are frequency count, percentage calculations, ranking, and Pearson correlation coefficient. Fire Incidence in the Province of Marinduque reveals a total of 58 fire events. The municipalities of Boac, Buenavista, Gasan, Santa Cruz, and Torrijos have similar fire causes, except for Mogpog, which has open flames or unsupervised cooking as the leading cause of fires in this area. The capability of the Marinduque Bureau of Fire Protection (BFP) in terms of tools, personal protective equipment, and the number of firetrucks indicates a varied landscape of readiness throughout towns, with an overall capability of 74.49% and a verbal description of "adequate." In terms of manpower, the total capability of the BFP in Marinduque is assessed as "adequate" at 62.06%. In terms of firefighting capability in terms of acquired skills and trainings. BFP staff possess a broad range of skills that can be categorized into three: hard skills, professional skills, and specialized skills. The firefighting capability in terms of adequacy and sufficiency of facilities and infrastructures yields a total mean for adequacy of 3.25, implying that these facilities, on average, provide what is necessary but with room for improvement. The total sufficiency mean is 3.06. BFP Marinduque has maintained a consistent budget utilization rate of 100% for the last five fiscal years. The mean performance ratings for various Fire Prevention activities range from 4.08 to 4.69, indicating that the BFP's performance is either "Very Satisfactory" or "Outstanding". There is a significant relationship of firefighting capabilities to the performance of BFP-Marinduque therefore null hypothesis is rejected. [ABSTRACT FROM AUTHOR]

Injecting carbon dioxide is the most effective means of preventing and extinguishing fires in sealing hazardous areas, but the traditional method slowly and remotely injects carbon dioxide gas into the well after gasification on the ground, which is dependent on the complete mine pipe network without cooling effect. To inject liquid directly from the tank with vacuum interlayer and heat insulating powder for rapid inerting and cooling, a new approach using track mobile platform to go deep into the underground mine disaster area is proposed, so the liquid can be delivered to the nozzle at the end of DN40 large diameter pipe, and the continuous gasification jet can be realized. The experimental results show that: (1) The liquid volume in a tank of vacuum degree within 2.0 Pa and 200 mm interlayer reduced no more than 15.5% after 48 days; (2) Taking the pressure in the tank as the power source, because of environmental differences inside and outside the pipe after 100 m pressure holding delivery, the physical form of liquid and gas could be converted instantly; (3) The continuous discharge time without ice blocking for a tank full of 2 m3 liquid was about 10.5 min under 25 L dual mode nitrogen pressurization, which is 1/12 of injection time after ground gasification; (4) Based on the temperature decrease trend measured at different positions, the cooling characteristics on liquid gasification jet path are quantified, and the calculation formula of temperature changing with time on the center line of liquid gasification jet is obtained. Through this new approach, the integration of vacuum insulated storage, safe mobile transportation, and continuous and rapid release with large flow can be achieved for the liquid carbon dioxide. [ABSTRACT FROM AUTHOR]

Currently, rural fire protection issues in China loom large, resulting in frequent fire incidents due to an inadequate rural fire infrastructure and insufficient firefighting resources. Consequently, prompt fire suppression becomes challenging, leading to significant casualties and economic losses. To address these challenges and align with the national rural revitalization strategy, our research team dedicated 5 years to meticulously scrutinizing fire incident data in China spanning from 2012 to 2022, alongside an extensive review of international documents. We conducted on‐site investigations in rural areas across 63 cities in 11 provinces, including Anhui and Jiangsu. By analyzing fire data and field investigation results, we identified the causes and percentages of 11 types of rural fires, as well as summarized five types of rural fire hazards and six types of rural fires. Drawing from insights gleaned from the experiences of countries such as the United States, Australia, Canada, and South America, we have formulated eight policy recommendations for rural fire protection, encompassing aspects like organization, responsibility, planning, construction, operation, and maintenance, as well as public awareness. Therefore, we anticipate that this study will catalyze enhancing rural fire protection efforts in China and other developing nations. [ABSTRACT FROM AUTHOR]

In this research, we conducted an experimental analysis of a Kerosene/air burner designed according to the FAA's proposed ISO 2685 standard. The burner serves as a vital tool for generating flames and burnt gases, simulating real-world conditions relevant to fire safety studies. The core objective of this study was to comprehensively characterize the burner's behavior. Through a series of experiments, we investigated the influence of the equivalence ratio on several key parameters, including the spatial distribution of gas temperature (monitored using thermocouples), heat flux (measured with heat flux gauges), and the composition of gas emission species. Notably, our findings revealed a significant correlation between the equivalence ratio and these parameters. Specifically, we observed that as the equivalence ratio increased, so did the flame temperature, heat flux, and heat release rate. This increase continued until a critical equivalence ratio value of 1.03 was reached, resulting in a flame temperature of 1101.5°C and a heat flux of 140 kW/m2. Furthermore, our study encompassed a pyrolysis test on various composite materials, including Carbon-phenolic, Carbon-BMI, and Carbon-PEKK. The comparative analysis of these materials highlighted the superiority of Carbon-PEKK, which exhibited the lowest mass loss, the highest back-face temperature without experiencing significant material delamination, and the lowest concentration of gas emission species. Importantly, our investigation also delved into the influence of the equivalence ratio on the flow's turbulence characteristics, a critical factor in comprehending the burner's performance and its interactions with materials in the context of fire safety scenarios. These findings contribute to a better understanding of combustion dynamics, which is invaluable for enhancing fire safety measures and developing more efficient flame-generating systems. [ABSTRACT FROM AUTHOR]

• Polymer pile, foam-backed carpet can produce horizontal fire spread. • Self-propagation of fire in polymer/foam carpet can link multiple seats of fire. • Self-propagation of fire in polymer/foam carpet leaves characteristic evidence. • Understanding the fire spread mechanism will reduce erroneous conclusions on causation. • Self-propagation of fire in polymer/foam carpet is a fire safety risk issue. An eight year old boy was badly injured by a fire in his bedroom in May 2005. He spent his ninth birthday in intensive care and died a month later. This case study discusses a missing link into the pattern of fire development which made it difficult to identify the point of ignition. An absence of burning to the floor and isolated areas of burning seemed incongruous with the general pattern of fire development. Several fire investigation texts suggest that carpet cannot spread fire by itself; those texts that do mention the possibility, do not describe the mechanism in detail, nor what evidence an investigator might expect to see after the fire. Experimentation with samples of carpet gave good insight into the mechanism and its effects, thereby providing the missing link by which to connect the areas of burning and identify the point of origin. If elements of the mechanism described in this paper are known, a reader could discern enough from the many papers available to support a working hypothesis but as yet, there is no single paper that describes the phenomenon mechanistically from start to finish, especially to those who have not encountered elements of it before; hence, this paper presents some novel findings. The test involved polypropylene fibre carpets with integral polyurethane foam underlay, a very common type of carpet owing to its low cost and high durability. This is, therefore, an important mechanism of fire spread for fire investigators to be aware of and to understand. As this is a case study, rather than a research paper, the matters are dealt with empirically so the author cautions that when considering this mechanism in a new matter, the investigator should make their own tests of its validity. [ABSTRACT FROM AUTHOR]

The ability to accurately identify fire patterns is the fundamental requirement for fire investigations. The corrosion layers of steel in fire scenes exhibit three distinct characteristics. First, due to steel's nonflammable nature, steel patterns can be preserved better at the fire site than patterns formed on other combustible materials; second, both the high temperature and the smoke during the fire affect the high‐temperature oxidation process; and third, the corrosion layer of steels inevitably undergoes further evolution after the fire because of the subsequent room‐temperature corrosion. This study focuses on investigating Q235 steel because of its extensive use in construction and vehicles. The pattern evolution processes of high‐temperature oxidation at elevated temperatures in air, polyethylene (PE), and polyvinyl‐chloride (PVC) combustion smoke and the corresponding subsequent corrosion at room temperature were systematically investigated from the perspective of macroscopic and microscopic morphology. The results showed that the smoke atmosphere played an important role in the formation of the corrosion layer of Q235 steel. Compared with samples oxidized in air, samples oxidized in PE combustion smoke exhibited a uniform and dense oxide layer on the surface, which inhibited the corrosion at room temperature further. The PVC combustion smoke accelerated the high‐temperature oxidation of the sample, and its influence on the subsequent room‐temperature oxidation process was closely correlated with the temperature of the high‐temperature oxidation. The results of this study provide important references for understanding the formation of the corrosion layer of Q235 steel for fire investigations. [ABSTRACT FROM AUTHOR]

This paper studies the fire performance of steel warehouse with their main elements insulated with fire protection boards composed of gypsum‐based mortars with perlite using the heat transfer and thermomechanical analysis in finite element (FE) software. The primary aim is to identify the optimal thickness of the fire protections boards based on the assigned fire model in thermal analysis. Besides that, a parametric study is also conducted by considering various factors that are often overlooked or not explicitly mentioned in fire design guidelines, such as EN 1991‐1‐2. The findings facilitate the development of optimized fire design approaches, ensuring the structural integrity and safety of steel warehouses under fire conditions. [ABSTRACT FROM AUTHOR]

The physics and the dynamics of static fires were studied numerically and experimentally by burning single Douglas fir trees. The mass loss rate was recorded, as well as the radiative heat flux and temperature at different positions. The numerical simulations were carried out using a fully physical CFD code (FireStar3D), and two levels of description were considered: in the first one, the vegetation was represented using a single fuel-type; in the second, four fuel-types were considered. The numerical results were compared to the experimental data for fuel moisture content of 14% and 50%. The results clearly show the advantage of considering several fuel-types to represent the tree; nevertheless, compared to the experiments, faster tree burning dynamics is obtained by simulation. The role played by the ignition process was also analysed numerically, highlighting the sensitivity of the tree burning dynamics to the ignition protocol. [ABSTRACT FROM AUTHOR]

In this paper, we create a virtuous cycle ecosystem of AI data for judging electric fire status. Data collection reflects feedback on inspection results such as collection of electric fire status judgment data through cloud sourcing and purification, processing, inspection and data disclosure of the collected data. It is necessary to determine the cause of the damage through fire forensics in order to confirm the property damage caused by the fire. The damage investigation so far is based on the experience of the investigator, and it is difficult to conduct a sufficient investigation and analysis of multiple fires. Accordingly, by building a data set for AI learning for the cause analysis of electric fires, The AI composition that can overcome the subjective and unprofessionalism of the forensic of electric fires is made. Therefore, we study the reliability and system development feasibility of digital conversion of fire detection report and data for AI learning. [ABSTRACT FROM AUTHOR]

Electrical fires frequently occur due to the ignition generated by electrical gadgets, wiring, cables, and multi-taps. These fires can cause numerous human casualties and property damage every year. The mechanisms that cause electrical fires are generally unique and require specialist research to understand their features fully. Due to the rising number of electrical fires, IT-based assessment models for electrical fire causes assessment have been proposed and experimented with to improve efficiency and accuracy. This survey aims to thoroughly examine and analyze the current advanced practices in detecting and evaluating electrical fire causes, focusing explicitly on IT-based assessment methods and simulations to provide a comprehensive review. The research objectives are achieved by conducting a survey on techniques and procedures utilized in prior works and research. Firstly, we introduce the survey of factors contributing to electrical fires. Next, electrical fire simulations to determine the causes and behavior of electrical fires are investigated. The assessment of electrical techniques to understand electrical fire causes has been emphasized. Lastly, the summaries and proposed enhancements to advance the progress in this domain are examined. To the best of our knowledge, this is the first time a survey on electrical fire causes assessment of IT-based approaches has been conducted. These findings are expected to become a valuable reference in this domain.

The analysis of charred bodies represents a serious challenge for forensic pathologists, and an interdisciplinary approach is often the only way to determine the cause and manner of death. We present an unusual case in which the charred body of a 61‐year‐old man was found inside his burning vehicle. In order to determine cause and manner of death, an interdisciplinary team was employed, with experts in forensic pathology, forensic radiology, toxicology and fire investigations. Post‐mortem computed tomography, autopsy and toxicology ruled out the presence of trauma injury and detected signs of vital exposure to fire and blood alcohol levels. On the other hand, according to fire investigations, the fire started inside the car and partially burned fragments of a garden hose were found along the right side of the car. A suicide could therefore be hypothesized, with the man having attempted to poison himself with the car's exhaust fumes and having set the car on fire. The death was consistent with a complicated suicide in which the victim, in a state of reduced capability, accidentally set his car on fire and was unable to escape. The hypothesis of a complex suicide, with the car having been set deliberately on fire, could not, however, be ruled out. [ABSTRACT FROM AUTHOR]

To overcome some limits of classical neuronal models, we propose a Markovian generalization of the classical model based on Jacobi processes by introducing downwards jumps to describe the activity of a single neuron. The statistical analysis of interspike intervals is performed by studying the first passage times of the proposed Markovian Jacobi process with jumps through a constant boundary. In particular, we characterize its Laplace transform, which is expressed in terms of some generalization of hypergeometric functions that we introduce, and deduce a closed-form expression for its expectation. Our approach, which is original in the context of first-passage-time problems, relies on intertwining relations between the semigroups of the classical Jacobi process and its generalization, which have been recently established in [P. Cheridito et al., J. Ec. Polytech. - Math., 8 (2021), pp. 331--378]. A numerical investigation of the firing rate of the considered neuron is performed for some choices of the involved parameters and of the jump distributions. [ABSTRACT FROM AUTHOR]

Considering the high level of risks that infection with the bacteria Erwinia amylovora has in apple orchards in Romania, we have undertaken a four consecutive years (2019-2022) investigation in terms of fire blight occurrence. In the experimental plots typical symptoms, such as wilted or necrotic shoots in the form of 'shepherd's crook, were visible for two consecutive years (2021-2022), while flower clusters were not affected. The highest damage degree was observed in 2022, when was recorded the least amount of precipitation in the May-June period, but accompanied by extreme phenomena, such as strong winds. At the same time, during the study, the average daily temperatures in the case of May were the highest in 2022, respectively the second highest, in the case of June, being exceeded only by June 2019. According to our observations, the climate changes in the area, which consist of both the increase of the average annual temperature and the occurrence of some extreme phenomena with greater frequency, are favoring factors to increase the occurrence of Erwinia amylovora and amplify the fire blight symptoms in apples. [ABSTRACT FROM AUTHOR]

In this work, a number of experiments were conducted in a reduced scale bifurcation tunnel with a ratio of 1:10 to explore the influence of the position of longitudinal fires (placed in branch tunnel) on smoke temperature profile under forced ventilation. Three heat release rates, six ventilation velocities, and three fire locations were considered. The main findings are summarized below, as follows: The temperature of smoke downstream of the main tunnel decreases with the rate of ventilation and longitudinal fire location. In contrast, the smoke temperature downstream of the fire source inside the branch tunnel drops with the ventilation velocity; the maximum temperature of the flame under the ceiling of the tunnel rises with longitudinal fire location. The dimensionless longitudinal smoke temperatures downstream of the main tunnel decrease exponentially with longitudinal distance, and the same observation is found in the branch tunnel. The attenuation coefficient k in the main tunnel increases with longitudinal ventilation velocity according to a power law but does not change significantly with longitudinal fire locations. However, the exponential coefficient k′ in the branch tunnel decreases linearly with ventilation velocity, whereas it increases with longitudinal fire location inside the branch tunnel. Lastly, modified models are established for estimating the longitudinal profile of temperatures downstream of the main tunnel and branch tunnel, where the influence of the rate of ventilation and location of the fire are taken into account. [ABSTRACT FROM AUTHOR]

The overcurrent fault of copper wire is an important cause of electrical fire, and the combustion process of which is relatively complicated. In this study, the rated current of 32A of the wire was taken, and the electrical fault simulation device was used. After the overcurrent Io was set to 128A, 160A, 192A, and 224A, respectively, to analyze the combustion evolution process of PVC‐insulated copper wire, the evolution of pyrolysis gas from the insulating layer, and the change of functional groups. The results show that when the overcurrent fault of PVC‐insulated copper wire happened, the core wire was turning red, the wire was deforming, the smoke was releasing, the insulating layer was dripping, the wire was fusing, and the continuous burning occurred. When the current Io < 160A, there was only one fusing point on the wire. In addition, when an overcurrent fault occurred in the PVC‐insulated copper wire, the temperature rise rate increased exponentially, which can be divided into three stages of the initial heat accumulation stage, the wire fusing stage, and the continuous burning stage. Furthermore, CO, HCl, CH4, olefins, and aliphatic and aromatic compounds were precipitated during the combustion process of the PVC insulating layer. The quality of the insulating layer decreased with the increase in temperature, and the weight loss rate was higher at 300°C. The conclusions of this study have provided experimental basis and technical support for the physical and evidence identification of fire accidents. [ABSTRACT FROM AUTHOR]