Fire Statistics Research Articles

분전반, 배전반 등에 사용하는 질산칼륨 기반의 소공간 소화장치의 성능에 관한 기초 연구 - 소화메커니즘 및 A급 소화성능을 중심으로

As there was no objective date on the fire extinguishing mechanism and performance of potassium nitrate-based small space fire extinguisher that can automatically extinguish fires in small spaces (less than 0.36 ㎡) such as distribution boards and distribution boards, we attemped to conduct basic research on this. We sought to confirm the importance of fires in switchboards and other devices through fire statistical analysis of electrical factors, and analyzed fire extinguishing mechanisms that react with heat based on potassium nitrate. We also sought to determine the interconnectivity of related variables through Class A fire extinguishing tests. Through analysis of fire statistics, the importance of electrical fires was confirmed and the cause of fire in the switchboard was investigated. By investigating its composition, it was found that it was a safe material that could be used for fire extinguishing, and that in the event of a fire, the thermal decomposition of KNO3 produced condensed aerosol particles, K2CO3, which could extinguish the fire. Through the Class A fire extinguishing test of the switchboard, it was confirmed that the fire could be reliably extinguished. The following conclusions were drawn through this study. 1. Analysis of fire statistics confirmed that electrical factors were the biggest cause of fire and that fires caused among this short circuit and insulation deterioration were the main causes. 2. The fire risk of switchboards, distribution boards, etc. was confirmed, and it was found that it was necessary to install simple fire extinguishers for small spaces that can quickly respond to and extinguish fires. 3. The fire extinguishing mechanism of potassium nitrate was confirmed to extinguish the fire by generating condensed aerosol particles, K2CO3, through thermal decomposition of KNO3 when a fire occurs. 4. Through the Class A fire extinguishing performance test, it was confirmed that there was a relationship between fire extinguishing delay time, weight, and volume, and the relationship could be expressed as , and it was found that a value of 1 or more is required for fire extinguishing.

Moment neural network and an efficient numerical method for modeling irregular spiking activity.

Continuous rate-based neural networks have been widely applied to modeling the dynamics of cortical circuits. However, cortical neurons in the brain exhibit irregular spiking activity with complex correlation structures that cannot be captured by mean firing rate alone. To close this gap, we consider a framework for modeling irregular spiking activity, called the moment neural network, which naturally generalizes rate models to second-order moments and can accurately capture the firing statistics of spiking neural networks. We propose an efficient numerical method that allows for rapid evaluation of moment mappings for neuronal activations without solving the underlying Fokker-Planck equation. This allows simulation of coupled interactions of mean firing rate and firing variability of large-scale neural circuits while retaining the advantage of analytical tractability of continuous rate models. We demonstrate how the moment neural network can explain a range of phenomena including diverse Fano factor in networks with quenched disorder and the emergence of irregular oscillatory dynamics in excitation-inhibition networks with delay.

Constructing neural networks with pre-specified dynamics

A main goal in neuroscience is to understand the computations carried out by neural populations that give animals their cognitive skills. Neural network models allow to formulate explicit hypotheses regarding the algorithms instantiated in the dynamics of a neural population, its firing statistics, and the underlying connectivity. Neural networks can be defined by a small set of parameters, carefully chosen to procure specific capabilities, or by a large set of free parameters, fitted with optimization algorithms that minimize a given loss function. In this work we alternatively propose a method to make a detailed adjustment of the network dynamics and firing statistic to better answer questions that link dynamics, structure, and function. Our algorithm—termed generalised Firing-to-Parameter (gFTP)—provides a way to construct binary recurrent neural networks whose dynamics strictly follows a user pre-specified transition graph that details the transitions between population firing states triggered by stimulus presentations. Our main contribution is a procedure that detects when a transition graph is not realisable in terms of a neural network, and makes the necessary modifications in order to obtain a new transition graph that is realisable and preserves all the information encoded in the transitions of the original graph. With a realisable transition graph, gFTP assigns values to the network firing states associated with each node in the graph, and finds the synaptic weight matrices by solving a set of linear separation problems. We test gFTP performance by constructing networks with random dynamics, continuous attractor-like dynamics that encode position in 2-dimensional space, and discrete attractor dynamics. We then show how gFTP can be employed as a tool to explore the link between structure, function, and the algorithms instantiated in the network dynamics.

Comparison of modulation efficiency between normal and degenerated primate retina.

With electrical stimulation, retinal prostheses bypass dysfunctional photoreceptors and activate the surviving bipolar or retinal ganglion cells (RGCs). Therefore, the effective modulation of RGCs is crucial for developing retinal prostheses. Substantial research has been performed on the ability of an electrical stimulus to generate a reliable RGC response. However, different experimental conditions show varying levels of how well the electrical stimulation evokes RGC spikes. Therefore, in this study, we attempted to extract an indicator to understand how the electrical stimulation effectively evokes RGC spikes. Six cynomolgus monkeys were used: three as controls and three as an N-methyl-N-nitrosourea (MNU)-induced retinal degeneration model. The retinal recordings were performed using 8 × 8 multi-electrode arrays (MEAs). Electrical stimulation consisted of symmetrical biphasic pulses of varying amplitudes and durations. The number of stimulation conditions that resulted in significantly higher post-stimulation firing rates than pre-stimulus firing rates was defined as the modulation efficiency ratio (MER). The MER was significantly lower in degenerated retinas than in normal retinas. We investigated the relationship between the variables and the MER in normal and degenerated primate RGCs. External variables, such as duration and inter-electrode distance, and internal variables, such as average firing rates and statistics (mean, standard deviation, and coefficient of variation [CV]) of inter-spike intervals (ISIs) of spontaneous spikes, were used. External variables had similar effects on MER in normal and degenerated RGCs. In contrast, internal variables affected MER differently in normal and degenerated RGCs. While in normal RGCs, they were not related to MER, in degenerated RGCs, the mean ISIs were positively correlated with MER, and the CV of ISIs was negatively correlated with MER. The most important variable affecting MER was the mean ISI. A shorter ISI indicates hyperactive firing in the degenerated retina, which prevents electrical stimulation from evoking more RGCs. We believe that this hyperactivity in degenerated retinas results in a lower MER than that in the normal retina. Our findings can be used to optimize the selection of stimulation channels for in vitro MEA experiments and practical calibration methods to achieve higher efficiency when testing retinal prostheses.

A Retrospective Analysis of The Causes of Industrial Fires in Istanbul Occurring Between 2015 and 2020

This study was conducted to analyze the causes of industrial fires that occurred in Istanbul from 2015 to the first half of 2020. An official application was made to the Istanbul Metropolitan Municipality Fire Brigade Department, which has archive data on this subject, to conduct the research and a sample set was created by filtering industrial fires from the data pool obtained after the approval of the application. In the analysis phase of the 4600 industrial fire data reached, the distributions of the fires according to years, the intended use of the property where the fire took place, the cause of the fire and the district where the fire took place were examined using the Chi-square analysis method. SPSS 22 software package was used in the analysis and the level of significance was determined as 0.05. The examination of the results of the analysis indicated that the leading cause of industrial fires in Istanbul between 2015 and 2020 was electrical equipment with a rate of 44.8%. Electrical equipment was followed by hot work equipment, heating equipment, cigarettes, flammable and explosive chemicals, cooking equipment and arson, respectively. In the study, the reasons of the fires obtained as a result of the analysis of the data were examined, a comparison with the US industrial fire statistics was made and recommendations for improving data and preventing the recurrence of industrial fires were made. In addition, it was emphasized that robust statistics on the causes of fires played an important role in the development of fire prevention strategies and legislation.

ОСОБЕННОСТИ ОРГАНИЗАЦИИ БЕЗОПАСНОСТИ НАСЕЛЕНИЯ И ПОЖАРНЫХ-СПАСАТЕЛЕЙ ПРИ ВОЗНИКНОВЕНИИ ЛЕСНЫХ ПОЖАРОВ В АРКТИЧЕСКОЙ ЗОНЕ

The article considers the problems on organization of safety of the population and fire-fighters-rescuers as a result of forest fires in the Arctic zone. It is connected with the scale and long-distance spread of forests, as well as with the conditions of harsh climate. On the example of the Republics of Karelia and Yakutia the statistics of forest fires for the period of the last six years is given. On the basis of the analysis of statistics of forest fires and causes of their occurrence the recommendations on increase of safety of the population and fire-fighters-rescuers at carrying out of actions on localization and liquidation of forest fires are formulated. They are reduced to strengthening of grouping in regions of the Arctic zone, improvement and equipping with modern technical means of protection and specialized equipment adequate to climatic conditions of the region, means of emergency evacuation of rescuers from critically dangerous zones.

Multi-day neuron tracking in high-density electrophysiology recordings using earth mover’s distance

Accurate tracking of the same neurons across multiple days is crucial for studying changes in neuronal activity during learning and adaptation. Advances in high-density extracellular electrophysiology recording probes, such as Neuropixels, provide a promising avenue to accomplish this goal. Identifying the same neurons in multiple recordings is, however, complicated by non-rigid movement of the tissue relative to the recording sites (drift) and loss of signal from some neurons. Here, we propose a neuron tracking method that can identify the same cells independent of firing statistics, that are used by most existing methods. Our method is based on between-day non-rigid alignment of spike-sorted clusters. We verified the same cell identity in mice using measured visual receptive fields. This method succeeds on datasets separated from 1 to 47 days, with an 84% average recovery rate.

Multi-day neuron tracking in high-density electrophysiology recordings using earth mover's distance.

Accurate tracking of the same neurons across multiple days is crucial for studying changes in neuronal activity during learning and adaptation. Advances in high-density extracellular electrophysiology recording probes, such as Neuropixels, provide a promising avenue to accomplish this goal. Identifying the same neurons in multiple recordings is, however, complicated by non-rigid movement of the tissue relative to the recording sites (drift) and loss of signal from some neurons. Here, we propose a neuron tracking method that can identify the same cells independent of firing statistics, that are used by most existing methods. Our method is based on between-day non-rigid alignment of spike-sorted clusters. We verified the same cell identity in mice using measured visual receptive fields. This method succeeds on datasets separated from 1 to 47 days, with an 84% average recovery rate.

Fire Risk Assessment in Museums on the HERIe Web-based Decision-supporting Platform

ABSTRACT Fire statistics indicate that fire, despite significant technical progress in the field of fire protection, is a significant risk to the long-term preservation of cultural property. Management of the risk requires tools which quantitatively relate the risk of fire to the characteristics of buildings and collections and the effectiveness of fire protection measures. Such tools must be accessible to, and useful for, conservation professionals and related decision-makers. To address the challenge, a module assessing fire risk for collections in museums has been developed on the HERIe online digital decision-supporting platform using the methodology proposed by Jean Tétreault transformed into a mathematical algorithm. It takes into account building characteristics and the proportion of the collection stored in showcases, as well as the vulnerability of the collection materials to heat, combustion, smoke, and water. This information is used to forecast loss to collection value over a selected time horizon. Fire likelihood is estimated from the fire statistics available in the user’s country, area, or organization. Risks to collections associated with correct and unwanted activation of automatic fire suppression systems are also considered.

A novel approach to feasible optimal cooperative search and coverage for wildfire emergency management

This paper presents a novel near non-dominated solution approach for distributed cooperative search and coverage (CSC) in uncertain environments for wildfire emergency management. The goal is to efficiently cover the extent of the wildfire and search for unknown stationary fire hotspots using a team of flying agents. Certain management factors such as time and the number of agents can directly impact the effectiveness of cooperative wildfire coverage and fire hotspots search in environments with scattered and widespread uncertainties. To address this, a near non-dominated solutions approach for a new CSC mission in a specific forest region is proposed in this paper. This approach involves generating a dataset based on previously completed wildfire management missions and probability features matching processes. Accordingly, prime and appointed surveillance regions are defined, and previously completed CSC missions are formulated as optimization problems to generate an optimal dataset. Afterward, the normalized cross-correlation algorithm is utilized to identify data that closely matches the probability pattern of the initial probability map of the current mission. By allocating the parameters of the identified data to the operational parameters of the current mission, the performance of the distributed cooperative fire hotspot search and wildfire coverage mission can be enhanced. This allocated data to the current mission serves as the near non-dominated solution. The effectiveness of the proposed strategy is validated and demonstrated via CSC simulations.

Temporal Characterization of Fire Accidents in China

Based on the fire accident statistics, this study uses the seasonal index method to comprehensively analyze the temporal pattern of fire occurrence in China from 2010 to 2015. The study scientifically reflects that the number of fire occurrences has an extremely close relationship with time, and summarizes the temporal pattern and characteristics of fire occurrences. This study concludes that the high incidence of large fire accidents in China occurs in the time period of 3:00 a.m. to 5:00 a.m. The probability distribution model of the average total number of accidents in each time period was established and the Kolmogorov test was carried out, which shows that the time characteristics of fire accidents in China can be understood with the probability distribution model as a whole. The results of the analysis of the time characteristics of the fire accidents can provide decision-making information for combating fire accidents.

Environmentally safe installation for determining the fire resistance of coatings and fire resistance tests of small fragments building structures

Actuality. Taking into account fire statistics, the task of preventing the occurrence and spread of fires is urgent. It is obvious that the fire resistance of building structures, which must be taken into account at the design stage, is of the greatest importance and influence on the development and spread of fires in buildings and structures. Conducting fire experiments makes it possible to obtain the most complete information about the behavior of building structures under fire effects, however, the scale of field tests, labor-intensiveness, energy consumption and damage to the environment prompts the search and development of alternative methods that would ensure the environmental friendliness of the tests, compliance with the conditions of the experiment ( standard fire temperature regime), and at the same time would make it possible to estimate the limit of fire resistance of a building structure in reduced dimensions or to experimentally determine the fire-resistant ability (efficiency) of fire-resistant coatings. Purpose. The main goal of the article is rationale use of an installation for determining the fire-resistant capacity (efficiency) of fire-resistant coatings and fire resistance tests of small-sized fragments of building structures, taking into account the reduction of the harmful load on the environment. Main results. Research has been carried out and the design features of the installation have been substantiated, the principle of which is to heat the inner space of the chamber with the help of electric heating elements, which, unlike liquid fuel (diesel fuel, fuel oil, gas), do not harm the environment. A control unit-module of variable voltage regulation designed to regulate the heating temperature of the radiation panel in the test chamber has been developed. The design of the created test setup makes it possible to increase or decrease the temperature on the heating surface of the test sample, not only with the help of the heating temperature regulator, but also in manual mode, by moving the test sample closer or further away from the radiation panel along the guides. Conclusions. According to the results of experimental tests, it was established that the chamber of the installation warms up uniformly and according to the standardized temperature-time dependence Ts = 345lg (8t+1)+20). At the same time, the temperature regulation process using BP-10 with triac output ensures stable operation of electric heating elements up to temperatures of 1000 °C. A feature of the created installation is the possibility of additional lowering or raising of the temperature on the heating surface of the experimental sample, in case of its deviation during the experiment, by means of approaching or moving away from the sample to the heating panel. The conducted studies confirm the necessary reproducibility of experimental results.

METHODOLOGY FOR STUDYING THE FIRE PROTECTION ABILITY OF A FIRE PROTECTION COATING BASED ON POLYSILOXANE AND OXIDES OF ALUMINIUM, TITANIUM, AND CHROMIUM FOR STEEL BUILDING STRUCTURES

Fires and their negative consequences are a significant problem today. The final report of the World Fire Statistics Centre in 2023 shows that an average of 3.7 million fires occurred annually between 1993 and 2021. The fire resistance of building structures has paramount importance and influence on the development and spread of fires in buildings and structures, which needs consideration at the design stage. Particular attention should be paid to metal structures when used in construction since their fire resistance limit is about 15 minutes, depending on the profile and cross-section of the structure, and this, in turn, limits their use in buildings and structures where the fire resistance class of structures is REI 15. A way to increase the fire resistance class of a steel building structure is its fire protection implemented using dedicated means that protect the steel structure from the effects of high fire temperatures. The study aims to develop a methodology and determine the heating time of prototypes of steel plates with a fire-retardant coating based on polysiloxane and oxides of aluminium, titanium, and chromium to a critical temperature depending on the coating thickness (0.3, 0.45, 0.6, 0.8 mm) and the thickness of the steel plate (0.3, 0.5, 0.8 cm). To determine the fire protection capacity of the developed fireproof coating, we used the method regulated by clause 7.4 of DSTU-N-P B V.1.1-29:2010 ‘Fireproof treatment of building structures. General requirements and control methods’. The authors have developed a methodology for conducting experimental studies of the effectiveness of fire protection coatings using an installation for determining the fire protection capacity (effectiveness) of fire protection coatings, the principle of which is to heat the interior of the installation chamber using electric heating elements. The heating time of the prototypes of steel plates with the developed fire protection coating to the critical temperature was determined, depending on the coating thickness and the thickness of the steel plate. We found that the extreme temperature in a steel plate with a thickness of 0.3 cm is reached at 23, 34, and 46 minutes with a coating thickness of 0.3, 0.45, and 0.6 mm, respectively. Experimental studies of steel plates with thicknesses of 0.5 and 0.8 cm have shown that with an increase in plate thickness at the same values of the thickness of the fire protection coating, the time to reach the extreme temperature increases by about 1 minute. At a coating thickness of 0.8 mm, for steel plates with thicknesses of 0.3 and 0.8 cm, the temperature on the unheated surface of the prototype did not reach the extreme value.Given the results obtained, it will be relevant to solve the inverse problem of thermal conductivity to determine the thermal and physical characteristics of the coating based on numerical data from experimental studies. Keywords: research methodology, standard temperature regime, fire protection coating, steel building structure.

Evaluating 900 Potentially Harming Fires in Germany: Is the Prescriptive Building Code Effective? German Fire Departments Assessed Fire Safety Measures in Buildings Through On-Site Inspections

Fire statistics mirror the outcome of fire prevention. Most fire statistics in Germany deal with the loss of life, value, and fire department actions (number of interventions, nozzles used, or alarm category like a false alarm). However, these results also represent the safety level the legislator has set through the prescriptive building regulations. The current statistics cannot evaluate the level of fire safety and the fulfillment or necessity of fire safety precautions. Today, expert judgment from firefighters is necessary to fill this gap. Here, we show the first evaluation of fire prevention and hazard protection measures by evaluating 900 potentially harming fires throughout Germany. In contrast to minor fires, these fires have advanced to the extent that they could potentially violate the protection objectives outlined in building regulations. The fire department association developed a questionnaire to evaluate the fire safety level and possibly reduce unnecessary fire safety regulations. One hundred twenty-three fire departments carried out the questionnaire, which are responsible for 25% of the German population. Fire prevention officers of the fire departments went to the scene after the fire was extinguished, and the fire safety concept of the building could be evaluated. We found a high rate of injuries, smoke spread, need for rescue by firefighters, and higher than expected firefighter response times after arrival at the scene. Surprisingly, smoke spread rates correlated with building height and not with building age. It was even possible to assess the risk of multiple casualties. Overall, the questionnaire results give insight into the current level of fire safety in existing buildings. Ways and rates for smoke and fire spread prove the importance of second escape routes and the influence of human misconduct. According to these results, current building code regulations are sufficient to prevent fire spread. On the other hand, smoke spreading is a severe threat to people’s safety. For example, the data shown can be applied in Bayes nets or other risk calculations to optimize individual building designs or even governmental building codes concerning fire safety engineering. Based on our observations, science, and building codes, authorities could in the future establish a performance-based building code instead of the current prescriptive code. This paper presents the first approach in Germany to quantify the expert judgment of fire departments and use it as a source of knowledge for fire prevention.

Survey and Investigation of Usage Status According to the Installation of Underground Fire Extinguisher Boxes in Korea’s Traditional Markets

Currently, traditional markets are structurally vulnerable to fire because of the dense concentration of old wooden buildings with tangled wires, such as aging facilities. Particularly in traditional markets, street vendors are usually disorderly located, and nearby roads are crowded due to illegal parking and vehicles stopping on the driveway. When a fire breaks out, it is difficult for the fire truck to enter, which is necessary to extinguish the fire in the early stages and prevent it from expanding into a large fire. With modernization, the number of fires is on the decline; however, fires in traditional markets continue to increase. According to the analysis of fire statistics from January to November 2023, 49 out of 819 fires in sales facilities were in traditional markets, accounting for 5.98% of fires in sales facilities. This is an increase of about 18 cases and an increase of 2.8% compared to fire statistics of about 3.19%, or 31 out of 972 fires at sales facilities as of 2017. Through these statistics, we can observe that the number of fires in sales facilities has decreased; however, the number of fires in traditional markets has increased. Traditional markets are at high risk of accidents due to the poor management of aging facilities and the lack of safety awareness among merchants. Specifically, in the event of a fire, which is likely to develop into a large fire in a short period due to structural problems, construction of high-density shopping malls, and mass loading of highly flammable goods, raising concerns about safety issues. As these problems have continued, the National Fire Agency has developed an emergency fire extinguisher box that could be buried underground in districts requiring fire prevention reinforcement, such as traditional markets and dosshouses. On January 20, 2018, and on May 2, 2018, ten units were first installed in the Seoul area. In this study, we conducted a survey on the current status of underground fire extinguishing systems boxed in traditional markets to identify the merchants' perceptions and analyze the operation of underground fire extinguishing systems boxed in the market.

Табиғи және техногендік сипаттағы өрттердің зиянды шығарындыларын талдау

Over the past decade, the number of natural and man-made fires has increased, which lead to great casualties, serious environmental pollution and large economic losses. The paper presents the statistics of forest and steppe fires for 2022 in the Republic Kazakhstan, and the statistics of deaths in emergencies associated with a fire. During forest fires, the composition of combustion products depends on the composition of wood and the conditions of its combustion. Accordingly, the emissions are carbon dioxide, nitrogen, carbon monoxide and sulfur dioxide. Also, the calculation of the explosion radius in the diesel fuel warehouse was made. It has been established that the maximum explosion pressure and flame temperature for mixtures of limiting composition are practically constant at different initial pressures. For a mixture of constant composition, these characteristics change significantly with an increase in the initial pressure. The composition of combustion products is analyzed at various initial pressures. From the analysis of time scales, area, facilities and equipment, ignition sources, types of emergency substances and liability, statistical results show that the most dangerous area is the loading and unloading area and the most vulnerable facility and equipment are storage tanks. Meanwhile, the proportions of ignition sources are distributed so evenly that the prevention of fire and explosion must be equally focused on several factors of influence. A vapor cloud explosion may be the most common type of accident at oil depots, and management responsibility dominates all accident causes. A visual interpretation of the obtained results is presented.

Lightweight Arc Fault Detection Method Based on Adam-Optimized Neural Network and Hardware Feature Algorithm

Arc faults are the main cause of electrical fires according to national fire data statistics. Intensive studies of artificial intelligence-based arc fault detection methods have been carried out and achieved a high detection accuracy. However, the computational complexity of the artificial intelligence-based methods hinders their application for arc fault detection devices. This paper proposes a lightweight arc fault detection method based on the discrimination of a novel feature for lower current distortion conditions and the Adam-optimized BP neural network for higher distortion conditions. The novel feature is the pulse signal number per unit cycle, reflecting the zero-off phenomena of the arc current. Six features, containing the novel feature, are chosen as the inputs of the neural network, reducing the computational complexity. The model achieves a high detection accuracy of 99.27% under various load types recommended by the IEC 62606 standard. Finally, the proposed lightweight method is implemented on hardware based on the STM32 series microcontroller unit. The experimental results show that the average detection accuracy is 98.33%, while the average detection time is 45 ms and the average tripping time is 72–201 ms under six types of loads, which can fulfill the requirements of real-time detection for commercial arc fault detection devices.

Collective neural network behavior in a dynamically driven disordered system of superconducting loops

Collective properties of complex systems composed of many interacting components such as neurons in our brain can be modeled by artificial networks based on disordered systems. We show that a disordered neural network of superconducting loops with Josephson junctions can exhibit computational properties like categorization and associative memory in the time evolution of its state in response to information from external excitations. Superconducting loops can trap multiples of fluxons in many discrete memory configurations defined by the local free energy minima in the configuration space of all possible states. A memory state can be updated by exciting the Josephson junctions to fire or allow the movement of fluxons through the network as the current through them surpasses their critical current thresholds. Simulations performed with a lumped element circuit model of a 4-loop network show that information written through excitations is translated into stable states of trapped flux and their time evolution. Experimental implementation on a high-Tc superconductor YBCO-based 4-loop network shows dynamically stable flux flow in each pathway characterized by the correlations between junction firing statistics. Neural network behavior is observed as energy barriers separating state categories in simulations in response to multiple excitations, and experimentally as junction responses characterizing different flux flow patterns in the network. The state categories that produce these patterns have different temporal stabilities relative to each other and the excitations. This provides strong evidence for time-dependent (short-to-long-term) memories, that are dependent on the geometrical and junction parameters of the loops, as described with a network model.

ОСОБЕННОСТИ ИССЛЕДОВАНИЯ ПОЖАРОВ, СВЯЗАННЫХ СО ВЗРЫВАМИ ТОПЛИВОВОЗДУШНЫХ СМЕСЕЙ

Explosions of fuel-air mixtures and their accompanying fires are perhaps the most common emergencies. A high probability of this kind of emergency is typical for both industrial facilities and the residential sector.
 When studying fires associated with deflagration (explosive) gorenje fuel-air mixtures, experts often face a number of questions that are difficult to solve when using the standard methodological approach used in the study of a classic fire. The article presents an expert analysis of fires caused by the ignition (explosion) of a fuel-air mixture. The paper also presents statistics of fires associated with explosions of fuel-air mixtures over the past five years, which provides data on the categories of objects and the nature of fuel-air mixtures.

Linking the future likelihood of large fires to occur on mountain slopes with fuel connectivity and topography

AbstractIn the long run, ongoing climate change is expected to alter fuel production as well as the frequency and severity of fire weather, which may result in an unprecedented frequency of extreme fire events. In this paper we propose a simplified and spatially explicit method to assess the probability of experiencing large fires, based on topography (slope length) as well as extent and aggregation of the forested area (fuel connectivity). We considered 21 homogeneous pyroregions covering entire Switzerland as a study case and computed the length of the upslope paths within the forested areas, simulating ignition points on a systematic 100 × 100 m square grid. We then compared the obtained path lengths for each pyroregion with selected historical large forest fire statistics (e.g., mean area of the largest 5% of fires, maximum burnt area per fire) collected over the course of the last 30 years. This resulted in rather high R2 values, ranging from 0.558 to 0.651. The proposed approach was shown to allow for an easy identification and geo-localization of potential hotspots in terms of the likelihood for large fires to occur in mountainous regions, which is a prerequisite for a targeted planning of fire management measures aimed at preventing large fires and related post-fire gravitative natural hazards.