Fire Risk Analysis Research Articles

BN-RA: A Hybrid Model for Risk Analysis of Overload-Induced Early Cable Fires

Cable overload is one of the most critical contributors to early cable fires. This study proposes a hybrid Bayesian network (BN)-based fire risk analysis model, to investigate the evolution of overload-induced early cable fire risks. In particular, the fire risk transmission paths caused by cable overload are reported, considering the critical factors that likely lead to fires. A BN with a specific structure was considered using the fire risk transmission paths. Later, given the risk index system, a hybrid fire risk assessment model caused by cable overload was developed based on the entropy weight method. Subsequently, the corresponding risk levels were evaluated based on the evolution of the fire risk, using numerical simulations. Finally, a case study was conducted to validate the proposed methods, and the results indicated that the proposed methods can effectively evaluate the state of the cable and explain the causes of fire risk, which can be used for early fire warnings.

Sensitivity analysis of input variables to establish fire damage thresholds for redundant electrical panels

In the worst case, a temporary ignition source (also known as transient combustibles) between two electrical panels can damage both panels. Mitigation strategies for electrical panel fires were previously developed using fire modeling and risk analysis. However, since they do not comply with deterministic fire protection requirements, it is necessary to analyze the boundary values at which combustibles may damage targets depending on various factors. In the present study, a sensitivity analysis of input variables related to the damage threshold of two electrical panels was performed for dimensionless geometry using a Fire Dynamics Simulator (FDS). A new methodology using a damage evaluation map was developed to assess the damage of the electrical panel. The input variables were the distance between the electrical panels, the vertical height of the fuel, the size of the fire, the wind speed and the wind direction. The heat flux was determined to increase as the vertical distance between the fuel and the panel decreased, and the largest heat flux was predicted when the vertical separation distance divided by one half flame length was 0.3–0.5. As the distance between the panels increases, the heat flux decreases according to the power law, and damage can be avoided when the distance between the fuel and the panel is twice the length of the panel. When the wind direction is east and south, to avoid damage to the electrical panel the distance must be increased by 1.5 times compared to no wind. The present scale model can be applied to any configuration where combustibles are located between two electrical panels, and can provide useful guidance for the design of redundant electrical panels.

Battery Train Fire Risk on a Steel Warehouse Structure

Lithium ion battery fire hazard has been well-documented in a variety of applications. Recently, battery train technology has been introduced as a clean energy concept for railway. In the case of heavy locomotives such as trains, the massive collection of battery stacks required to meet energy demands may pose a significant hazard. The objective of this paper is to review the risk evaluation processes for train fires and investigate the propagation of lithium ion battery fire to a neighboring steel warehouse structure at a rail repair shop through a case study. The methodology of the analyses conducted include a Monte Carlo-based dynamic modeling of fire propagation potentials, an expert-based fire impact analysis, and a finite element (FE) nonlinear fire analysis on the structural frame. The case study is presented as a demonstration of a holistic fire risk analysis for the lithium ion battery fire and results indicate that significant battery fire mitigations strategies should be considered.

Fire risk assessment for building operation and maintenance based on BIM technology

Building fires are the most common types of fires, and most fires occur during the operation and maintenance periods of buildings. A majority of the risk factors causing fire are inextricably linked to human life, which can only be controlled but not eliminated. Fire risk assessment is necessary to control fire risk and improve the preventive ability. The assessment method established in this study can scientifically calculate the fire risk value by quantifying the fire risk index of buildings. Combined with BIM technology, this method can quickly and reliably assess the fire risk of the target building model and realise the organic unity of science, effectiveness and economy. Based on the fire risk analysis method for engineering (FRAME), we propose an assessment index system for buildings in the operation and maintenance periods in terms of the potential risk level, acceptable risk level and protection level. In addition, a risk value calculation model for the operation and maintenance periods is established, and the risk value assessment standard is set to improve the firefighting ability of buildings. Furthermore, the assessment indexes are incorporated into the family attributes in Revit software to realise the information interaction between the assessment system and the model. The results show that BIM technology can be applied effectively to fire safety, to ensure that the fire risk prevention and control ability of the target has a more intuitive scientific basis. It also provides a direction and ideas for the development and application of BIM technology.

Evidence based risk analysis of fire and explosion accident scenarios in FPSOs

The paper proposes a methodology for risk assessment and probabilistic modelling of fire and explosion accidents in Floating production storage and offloading (FPSO) units. The overall objective of the paper is to propose a Bayesian Network probabilistic framework towards quantification of fire and explosion events in FPSOs derived from a systematic analysis of incidental and accidental scenarios specific to FPSOs. A data set of around 800 incidents in FPSOs from various open-source agencies is prepared and analysed. The key features of the incidents are discussed and the relationships amongst the significant variables influencing the types of incidents are assessed. The circumstances of potential incidents related to fire and explosions are discussed. A detailed risk analysis is conducted using the risk matrix approach to screen and rank the major accidents occurring in FPSOs. Then, a Bayesian Network model of high-risk fire and explosion scenarios is developed based on evidences obtained from accident reports and expert opinions. The model uses a framework based on immediate causes, basic causes and causal factors to demonstrate various accidental scenarios specific to FPSOs. A sensitivity analysis is conducted to identify the most important causal factors and the aspects that need more research work for decision-making. The contribution of the present study is threefold: a methodology for comprehensive risk assessment in FPSOs is proposed; FPSO specific incidents and accidents are characterized; a probabilistic model for fire and explosion scenarios is developed from a causal framework. The results of the paper provide FPSO developers and operators with information to prevent and mitigate fire and explosion accidents.

Multi-criteria analysis and mapping of forest fire risk in Muğla Regional Directorate of Forestry

Orman yangın riskinin CBS temelli ve çok kriterli analizi; orman yangını riskini etkileyen en önemli kriterlerin tanımlanması, değer aralıklarının ve risk sınıflarının belirlenmesi, kriterlerin karşılaştırılması ve sonuç olarak risk endeksi ve risk haritasının üretilmesi aşamalarından oluşmaktadır. Bu çalışmada, Muğla Orman Bölge Müdürlüğü’nde (OBM) orman yangını riskinin hesaplanabilmesi için son 10 yılda (2010-2019) meydana gelen orman yangınları CBS ile analiz edilmiş, bu analizler arazi çalışmaları ile desteklenmiş ve özgün bir risk kriterleri tablosu düzenlenmiştir. Sonuç olarak Muğla OBM için risk endeksi hesaplanarak bir orman yangını risk haritası oluşturulmuştur. Çalışmanın esas hedefi, Muğla OBM baz alınarak, Türkiye’de orman yangını riskinin analizinde daha doğru sonuçlar alınmasını sağlamak amacıyla ve arazi ölçümlerinin de yardımıyla mümkün olduğu kadar objektif kriter değerlendirmeleri yapılması konusunda bir model oluşturmaktır.

Analysis of fire risk in the Amazon: a systematic review

Fires such as those that occurred in 2019 in the Amazon are examples of the intensification of these events in recent years and contradict the claim that forest fires only reach great proportions in years of extreme drought. This is a worrying scenario, as the Amazon Rainforest plays an important role in regional and global climate regulation. This study therefore sought to identify the methodologies used to describe and predict fire events in the Brazilian Amazon. For this, a systematic literature review was carried out in the open access databases Scientific Electronic Library Online (SciELO) and Directory of Open Access Journals (DOAJ) using the descriptors “fire risk” and “Amazon”, and their variants in the Portuguese language and the logical operator “AND” in the search. From the resulting search materia we identified the use of predictive models based on projections for climate change developed by the Intergovernmental Panel on Climate Change (IPCC), which indicate a substantial increase in the probability of fires. Another technique used is the crossing of heat foci data with the forms of land use, evidencing the areas that burn the most and when, as well as the most susceptible areas. There were also studies analyzing the performance of fire risk indexes, demonstrating those that could be used after adaptations to local characteristics. These results allow an understanding of the behavior of fire in the Amazon, since they provide a broad view of how studies on fires have been conducted and what techniques have been used.

Using the Landsat Burned Area Products to Derive Fire History Relevant for Fire Management and Conservation in the State of Florida, Southeastern USA

Development of comprehensive spatially explicit fire occurrence data remains one of the most critical needs for fire managers globally, and especially for conservation across the southeastern United States. Not only are many endangered species and ecosystems in that region reliant on frequent fire, but fire risk analysis, prescribed fire planning, and fire behavior modeling are sensitive to fire history due to the long growing season and high vegetation productivity. Spatial data that map burned areas over time provide critical information for evaluating management successes. However, existing fire data have undocumented shortcomings that limit their use when detailing the effectiveness of fire management at state and regional scales. Here, we assessed information in existing fire datasets for Florida and the Landsat Burned Area products based on input from the fire management community. We considered the potential of different datasets to track the spatial extents of fires and derive fire history metrics (e.g., time since last burn, fire frequency, and seasonality). We found that burned areas generated by applying a 90% threshold to the Landsat burn probability product matched patterns recorded and observed by fire managers at three pilot areas. We then created fire history metrics for the entire state from the modified Landsat Burned Area product. Finally, to show their potential application for conservation management, we compared fire history metrics across ownerships for natural pinelands, where prescribed fire is frequently applied. Implications of this effort include increased awareness around conservation and fire management planning efforts and an extension of derivative products regionally or globally.

Experimental and Numerical Analysis of Fire Risk in Historic Chinese Temples: A Case in Beijing

ABSTRACT To analyze the extent of fire risk in historic Chinese wooden structure buildings, the fire load characteristics of a historic temple in Beijing were studied. In this paper, thermogravimetric and cone calorimeter experiments were conducted on raw wood collected from historic Chinese buildings. Based on the experiment results, temple fire experiments were conducted in a full-scale model temple with high fire load in a historic Chinese wooden structure temple. FDS software was used to explore the characteristics of fire growth and spread in the initial fire. The results demonstrated that the pyrolysis kinetics parameters of historical wood were smaller than those of fresh wood. The reference temperature at 150°C with wood density of 410 kg/m3 in wooden structure building fire simulation was relatively credible. Flashovers are more likely to occur in historic wooden structure buildings of lower wood density and pyrolysis parameters.

Investigation of Tourism Interaction with Forest Fire Risk Areas in Cirali Region

Forest fires appear as a real destruction with human activities or natural forces. Despite the impossibilities to control the nature, it's possible to map fire risk areas and reduce the number of fires and prevent the damages. GIS can be used effectively to create a forest fire risk map with the capacity to evaluate the factors that cause fire. Cirali region, which is under constant fire threat were chosen for this research. Cirali region is located in Antalya province, southwest of Turkey as an agricultural village and a tourism area. As a result of the fire risk analysis, it has been determined that is concentrated around the residentials with high fire risk and the roads connecting the residentials. The interaction between Cirali region tourism and forest fire risk is analysed with the DPSIR model that shows the fire risk factors affecting the tourism in the region directly or indirectly.

Fire and explosion Risk Analysis Using Bow-Tie Method and Fuzzy-Bayesian Network in Process Industries

Fire and explosion Risk Analysis Using Bow-Tie Method and Fuzzy-Bayesian Network in Process Industries

Parameters that affect tenability conditions during fire emergency in metro tunnels

Underground spaces are characterized by special conditions and complexity, as well as by severe consequences in the event of an accident. Although the frequency of fire accidents in tunnels or metro stations is low, in worst cases they may lead to severe fatalities and damages. In order to have a more accurate prediction of fire impacts, most safety standards enforced worldwide suggest the development of special risk analyses. This needs to be made having in mind fire characteristics, geometrical and ventilation parameters so as to have an accurate view of the thermal and smoke propagation within the underground space. In this paper a parametric analysis is carried out, varying input values, crucial for fire risk analysis, like fire curve and heat release rate maximum (HRRmax), as well as ventilation and tunnel geometry. Key factors like visibility conditions, temperature and CO concentration are recorded through the fire dynamic simulation (FDS), in order to determine the conditions inside the metro tunnel. Furthermore, the fractional effective dose (FED) that occupants might receive in a period of time, in different positions inside the tunnel, is calculated. Based on the above, detailed data on the prevailing conditions are gathered and conclusions can be drawn regarding the influence of each parameter’s evolution on the tenability conditions inside the tunnel. Hence, the analysis can illuminate key issues to consider for performing an accurate risk analysis in an underground environment.

A multivariate approach to assess the structural determinants of large wildfires: evidence from a Mediterranean country

This paper analyses the factors behind wildfire propagation in a Mediterranean European country, Portugal, using a set of variables related to vegetation and climatic, topography and human aspects. Spatial cluster analysis was used to find homogeneous regions, and two-part regression models were used to model the contribution of the different elements driving extensive fire propagation. Our findings confirm the presence of spatial variability in the contribution exerted by most structural factors driving large wildfire spread. Additionally, the results of this study show that vegetation types, in particular the presence of shrubs, and a lack of human activities, such as agriculture, represent the main factors facilitating fire spread in this region, corroborating information from previous work. This research provides relevant input for implementation in different fields, from large fire awareness and prevention to the development of wildfire policies, as well as addressing methodological concerns in fire danger and fire risk analyses.

Analysis of the indoor fire risk based on the Pyrosim simulation

In order to study the effects of different fire conditions on the indoor fire process, this paper uses Pyrosim to perform a fire simulation of a simple indoor room in the paper, we have compared and analyzed the changes of the temperature, the smoke layer height, and the heat flow in two different conditions with the window and door being open, or with the window closed but the door opened 30 seconds later after the fire broke out. Pyrosim simulation results show that in the first 30 seconds of the fire outbreak, the fire development has nothing to do with the opening and closing of doors and windows. In the middle and late stages of the fire, when the door and window are fully open, the temperature and heat flow of the simulated room are low, and the height of the smoke layer from the ground is high. In the simulated room, with the window closed and the door opened after 30 seconds, the maximum temperature in the simulated room was about 10 higher than that in Condition 1.

城市地下空间火灾风险分析及防范对策

城市地下空间火灾风险分析及防范对策

Understanding Asset Management, a Fire Risk and Life Safety Analysis

Understanding Asset Management, a Fire Risk and Life Safety Analysis

Harmonized dataset of surface fuels under Alpine, temperate and Mediterranean conditions in Italy. A synthesis supporting fire management

Surface biomass characterization plays a key role in wildfire management. It allows classifying vegetation fuels flammability for fire risk analysis, to define silvicultural prescriptions for fire hazard reduction, to plan prescribed burning, or to model fire behavior and its effects, such as greenhouse gas and pollutant emissions. To facilitate fuel classification and analysis of potential fire behavior and effects in Italy, we harmonized 634 measurements of surface wildland fuels from Alpine, temperate and Mediterranean environments. The dataset provides quantitative data for duff, fine dead fuels and downed woody material, live grasses and shrubs fuel components. Surface fuel data were harmonized by subdividing loads (Mg ha-1) to standard size classes for dead (0-6, 6-25 and 25-75 mm) and live (0-6, 6-25 mm) fuels, collecting percent cover and depth/height (cm) of the various fuel components, and classifying observations into 19 fuelbed categories. To ensure comparability with existing vegetation classification systems, we classified each observation according to the European Fuel Map, the Corine Land Cover classes (level IV), the European Forest Types, and the forest categories of the Italian National Forest Inventory. The dataset and a photo description of each fuelbed category are available as Supplementary material. This dataset is the first step to develop several products at the national scale such as: (i) fuel type classification and mapping; (ii) carbon stock and wildfire emission estimates; (iii) calibration of fuel models for the simulation of fire behavior and effects.

Effects of Welding Time and Electrical Power on Thermal Characteristics of Welding Spatter for Fire Risk Analysis

To predict the fire risk of spatter generated during shielded metal arc welding, the thermal characteristics of welding spatter were analyzed according to different welding times and electrical powers supplied to the electrode. An experimental apparatus for controlling the contact angle between the electrode and base metal as well as the feed rate was prepared. Moreover, the correlations among the volume, maximum diameter, scattering velocity, maximum number, and maximum temperature of the welding spatter were derived using welding power from 984–2067 W and welding times of 30 s, 50 s, and 70 s. It was found that the volume, maximum diameter, and maximum number of welding spatters increased proportionally as the welding time and electrical power increased, but the scattering velocity decreased as the particle diameter increased regardless of the welding time and electrical power. When the measured maximum temperature of the welding spatter was compared with an empirical formula, the accuracy of the results was confirmed to be within ±7% of the experimental constant C=112.414×Pe−0.5045. Results of this study indicate quantitatively predicting the thermal characteristics of welding spatter is possible for minimizing the risk of fire spread when the electrode type and welding power is known.

GIS-based Fire Risk Assessment and Fire Station Site Selection——Taking Dujiangyan City as An Example

This study takes the urban area of Dujiangyan City as the research area, ten risk assessment factors are selected to conduct the fire risk assessment and analysis, including substations, building floor area ratios and miniature fire stations, and uses analytic hierarchy process, buffer analysis and overlay analysis. The minimize facilities model and maximize coverage model in location allocation model (LA model) are used to optimize fire station site selection. The research results show that there are still greater fire risks in the south and northeast of Dujiangyan City. The addition of two small and medium-sized fire stations in the north section of Yanhua road and in south section of Rainbow Avenue can basically realize to cover the areas with higher fire risks thoroughly.

Development of a 3D risk analysis technique for fire disaster and its application on accident simulation of a public site

In this research, we constructed a three-dimensional fire risk analysis technique (3D-FRAT) for common building fires. To demonstrate its effect, the 3D-FRAT employed a self-developed 3D risk-calculating module in combination with the Fire Dynamics Simulator (FDS) software to simulate the Welcome Restaurant accident that happened on February 15, 1995 in Taichung City, Taiwan. This study only focuses on thermal radiation and provide a preliminary method to quantify a fire risk. Different firefighting equipment that comply with the related building and fire-preventive regulations have been used in the simulations to test their mitigating effectiveness on the accident. The results were shown by animation, 3D pictures, and sliced pictures to facilitate the researchers’ understanding of human hazards caused by thermal radiation or smoke in a specific fire accident. The minimal personnel escaping times for different hazardous factors were estimated; various firefighting designs that can reduce loss of human life and property were also perused. According to the simulation results, the individual risk values in Welcome Restaurant were between 3.108 × 10−9 to 2.719 × 10−5 (deaths/year). It is foreseeable that the 3D-FRAT can become a useful tool for related organizations to choose better fire-resistant buildings or fire-fighting equipment in the future.