Establishing the engineering properties of cement-based composites at elevated temperature requires costly, laborious, and time-consuming experimental work. Data-driven models can provide a robust and efficient alternative. In this study, extreme learning machine (ELM), support vector machine (SVM), artificial neural network (ANN), and decision tree (DT) models were trained to predict the residual compressive, splitting tensile, and flexural strengths of hybrid fiber-reinforced self-compacting concrete (HFR-SCC) exposed to high temperatures. Mixtures including macro and micro steel fibers, polyvinyl alcohol (PVA), and polypropylene (PP) were subjected to different temperature levels, leading to an experimental database of 360 specimens. Eleven input parameters including cement, fly ash, water, sand, gravel, fiber type, water reducer, and temperature were deployed. The residual mechanical strengths were targeted as output parameters. ANOVA was used to explore the influence of input parameters. Temperature was found to be the most influential parameter. Dataset consisting of 114 instances was retrieved from pertinent literature and used along with the authors’ experimentally generated dataset for residual strength prediction. The experimental results were compared with predictions of ELM, SVM, ANN, and DT. ELM achieved superior performance and can offer a robust tool for predicting the residual mechanical strengths of HFR-SCC upon exposure to high temperature.

Fires with a heat release rate that grows quadratically in time and levels off after the first automatic fire sprinkler is activated are routinely used in evaluating the consequences of fire in performance based design projects. In order to calculate the sprinkler activation time one needs to solve the differential equation that governs the heat transfer between the ceiling jet and the sensing element of the automatic fire sprinkler, an equation that depends on the temperature and velocity of the gas. Well-known empirical correlations between ceiling jet properties and heat release rate as well as numerical simulations can be used to determine the temperature and velocity of the gas. Here a comparison and discussion of the results obtained for the activation time and activation heat release rate using both approaches is presented, which can help authorities having jurisdiction to assess safety reports when there are no clear regulations about which method should be applied.

In airworthiness verification flight test on fire smoke detection systems in aircraft cargo compartments, simulated smoke from a smoke generator that can replicate the characteristics of actual fire smoke should be used. In current studies, most of the boundary conditions of smoke generators are adjusted by open-loop control to fulfill the equivalence of the actual fire smoke. However, this method consumes a large amount of resources and has difficulty achieving optimal results from the complex turbulent flow field of smoke in an aircraft cargo compartment. To solve this problem, a computational fluid dynamics (CFD) model was first established to simulate smoke in the full-scale cargo compartment mock-up. Then, a state-space model with the exit parameters of the smoke generator as the input and the smoke concentration in the full-scale cargo compartment mock-up as the state variable was constructed using the data generated by the CFD model. Subsequently, a closed-loop simulated smoke concentration control strategy is proposed. In this strategy, the sensor in the full-scale cargo compartment mock-up collects the simulated smoke concentration signal and feeds it back to the controller. The controller processes the control target and feedback signal in real time. It realizes the automatic closed-loop control of the simulated smoke concentration by automatically adjusting the boundary condition parameters of the smoke generator. In the control law design, the control input constraint and the error between the linear state-space model and the real flow are considered, making the linear state-space model a nonlinear model. Finally, we prove the stability of the control system. The simulation shows that the designed control law can realize the closed-loop control of smoke concentration. The findings of this study can expand the control of simulated smoke flow field in airworthiness verification flight test from open loop to closed loop, and offer a new theoretical approach for smoke simulation technology.

National Fire Protection Association standard 1403 provides the fire service with guidance for conducting effective live fire training with the goal of minimizing health and safety hazards. The document provides guidelines for materials to be included in the training fuel package, but the fire service has raised questions about the use of specific types of wood products for this purpose. In this study, the fire dynamics generated when utilizing five different Class A materials that have been historically employed as training fuels [low density wood fiberboard, oriented strand board (OSB), pallets, particle board, plywood] in a single compartment fire training structure (Fire Behavior Lab) were characterized. A specific focus was placed on understanding the thermal and visual environment created for firefighters located at typical locations for instructors (front and rear of structure) and students (middle of the structure). The pallet fuel package required the longest time to transition through the six ventilation cycles while the OSB fuel package was the quickest. Additionally, the most consistent fire dynamics were demonstrated with the OSB fuel followed by particle board and plywood, while fiberboard and pallets resulted in less repeatable flashover or rollover demonstration. The OSB fuel package resulted in the highest peak heat fluxes and pallets resulted in the lowest. The most severe exposures were measured at the front instructor location. To control thermal risks when conducting training in the Fire Behavior Lab structure, instructors and students should orient themselves as low as possible in the observation area and behind the interior baffle when possible. Considering the high radiant exposures for the front instructor location, providing a local shield and reducing the time in the training structure can also reduce risk for thermal injury or personal protective equipment damage. Overall, different fuels can impact thermal exposures to firefighters, but varying fuels also affects the consistency of the fire dynamics being presented to the firefighting students.

Along with the rapid urbanization and economic growth in China over the last four decades, the higher education in Fire Safety Science and Engineering has been developed and changed significantly. This work systemically reviews the origin and evolution of fire safety higher education history in China, from Fire Protection Technology (before the 1980s) to Fire Safety Science and Engineering (from about 1985 to the 2010s) and to Human-Oriented Public Safety and Smart Firefighting (from the 2010s to today). The scopes of fire safety discipline are discussed by introducing the requirements of firefighters, registered professional fire protection engineers and safety engineers in China. The courses and curriculum in fire safety higher education in representative universities are introduced and compared in detail. By comparing their undergraduate and postgraduate programmes, we explain the context of fire safety education in different universities. From a historical viewpoint, we introduce the unique features and the diversity developed in different institutes, based on the evolution of programme documents and first-hand teaching materials. This review aims to introduce the higher education systems of fire safety in China to the world and encourage more international collaboration with the Chinese fire safety science and engineering communities in the future.

The analysis of the current state of fire statistics and data collection in Europe and other countries is needed to increase awareness of how fire incidents affect buildings and to support pan-European fire prevention and fire mitigation measures. The terminology and data collected regarding fire incidents in buildings in the EU Member States were mapped to obtain meaningful datasets to determine common terminology, collection methodology, and data interpretation system. An extensive literature review showed that fire data collection systems have been instrumental in informing firefighting strategies, evidence-based planning, prevention, and educational programmes. Differences and similarities between fire data collection systems were also investigated. The amount and quality of the information in fire statistical recording systems appear to be influenced by the complexity and structure with which the data are collected. The analysis also examined the existing fire statistics in the EU Member States and a few other countries. Finally, a detailed investigation of the number of fires, fire deaths, and injuries from 2009 to 2018 in several countries was examined based on data from a report by CTIF. The trends showed differences attributable to the existing fire statistical practices in terms of terminology and data collection, and interpretation. Part II proposes a common terminology for selected fire statistical variables. The results provide relevant information regarding fire safety at the European level and should be used to guide the development of more uniform fire statistics across Europe.

Reinforced concrete as the most important construction material suffers from long-term deterioration due to different exposure conditions. Fire attack is a critical exposure condition as it can lead to complete collapse of the structure. On the other hand, the repair and strengthening of existing structures have become necessary both technically and financially. Moreover, since high-performance concretes (HPCs) are extensively used as repairing or strengthening materials for different structures, their performance after exposure to elevated temperature needs to be investigated. Therefore, this study is directed to investigate the post-fire flexural behavior of RC slabs cast with traditional normal strength concrete (NSC) and strengthened with HPC. Twenty-one RC slabs were prepared and tested including casting the full thickness with the same mixture (single-concrete slabs) and composite slabs (cast with NSC and HPC). Different variables were considered; using high strength concrete, 30% fly ash, 30% slag, 0.5% polypropylene, 0.5% steel fibers, hybrid fibers (0.5% steel + 0.5% polypropylene), reinforcement ratio, the side exposed to elevated temperature (tension or compression), and joining the HPC layer to the NSC (shear studs or epoxy resin). The slabs were exposed to the required temperature of 600°C for 2 h. The results show that strengthening the RC slab in tension or compression by using HPC remarkably enhanced the slab’s performance after exposure to elevated temperature. Specially, composite slabs containing hybrid fibers in tension side when exposed to elevated temperature from the tension side recorded the highest cracking load, ultimate load, stiffness, toughness, and ductility index as compared to the NSC slab, with increases of 92.8%, 116%, 157%, 335%, and 86.9%, respectively.

The number of people living in informal settlements has been growing in the last decades, as well as the fire-related issues brought by this condition. Although fire incidents are frequent in Brazilian informal settlements, a lack of fire statistics for such fragile areas is observed. For this reason, this paper introduces the problem of informal settlement fires in Brazil and discusses the lack of statistics and reliable records related to these occurrences, showing the difficulties brought by this lack of data. To cope with that, an alternative method to identify the city regions more prone to informal settlement fires has been proposed. This alternative method employs consolidated social indexes (municipal human development Index–MHDI, Social Vulnerability Index–SVI, Population Density in informal settlements, and Income Inequality Coefficient) to indicate fire-vulnerable areas in a Brazilian city (Porto Alegre). Online press news was used as the data source of fire occurrences and related deaths, which occurred between 2016 and 2021 in the city of Porto Alegre/Brazil. The results did not show a relation between fire-vulnerable areas and MHDI, but it was observed that all city regions with very high SVI presented informal settlement fire occurrences, while the population density in informal settlements was an indicator of regions at high fire risk. Additionally, it has been shown that income inequality could be used as a complementary index to point to areas vulnerable to informal settlement fires. Comparing the income inequality index and population density in informal settlements index of all city regions, it was shown that the regions with the highest indexes had more informal settlement fire occurrences identified from the online press. The introduced method suggested that social indexes already quantified for the city could be analysed together to identify the areas of the city more prone to suffer from informal settlement fires, when these areas cannot be identified through fire statistics (due to the lack of these statistics). Knowing the city’s regions more prone to informal settlement fires can assist policymakers and governmental authorities in recognizing social needs and taking part in related actions for those areas. Further studies are recommended to confirm the applicability of the presented method for informal settlements worldwide, which could include not only fires but also other hazards and disasters as well as other social metrics locally available.

The expensive nature and unique facilities required for fire testing make it difficult to conduct comprehensive experimental campaigns. As such, engineers can often afford to test a small number of specimens. This complicates attaining a proper inference, especially when addressing questions in the form of what would have been the fire response of a particular specimen had it been twice as large? Or had it been made from a different material grade? In hindsight, answering causal and hypothetical (counterfactual) questions goes beyond the capacity of statistical and machine learning methods which were built to address observational data. To overcome the above challenges, this paper presents a causal approach to answering such questions. In this approach, principles of causal inference are adopted to reconstruct the deformation-time history of reinforced concrete (RC) columns and propose an idealized fire response for these columns. The findings of this study indicate the significant influence of the loading level, aggregate type, and longitudinal steel ratio on the deformation history of fire-exposed RC columns.

The flammability of twelve (12) different alcoholic beverages was experimentally determined by means of flash point testing. The flash point of a liquid fuel is the temperature at which a pool of the substance produces enough flammable vapor to support a momentary flame that propagates over the surface of the pool when an external flame is introduced. The flame then subsequentially extinguishes due to the vapor being consumed. Similarly, the fire point is the temperature at which the pool sustains a flame for at least 5 s. The flash point and fire point of a fuel is dependent on the test method used for their determination. This study used the ASTM D92 method for an open-cup apparatus and the ASTM D3941 method for a closed-cup apparatus. Beers, wines, and liquors ranging from 5% to 94.5% alcohol by volume (%ABV) were tested. The goal of the selection was to supplement existing data on the flash point of alcoholic beverages and to determine if the type of alcohol (rum, vodka, wine, beer, etc.) or the derivative product (corn, sugar cane, potatoes, etc.) has an effect on the flash point or fire point of the liquid. It was concluded that %ABV is the most significant factor that influences flash or fire point when utilizing equivalent experimental test methods, and that the type of alcohol has no significant effect on ignition risk.

This paper presents experimental and numerical results of an investigation into the thermal and structural behaviour of an innovative modular structural steel system, which includes cellular beams, that was tested in a 1-h standard fire scenario while loaded. The modular system consists of a 5.66 × 3.8 m rectangular steel frame, with a profiled steel sandwich decking (SD) system attached, which comprises of (a) profiled steel decking, (b) fibre cement, and (c) calcium silicate boards and strips. The SD system is suspended from the underside of the horizontal structural members to provide inherent fire protection to the steel beams from the bottom and acts as the load-bearing component of the flooring. The purpose of the experiment was to determine the fire resistance of the structural system, whilst under load, which is primarily based on the fire resistance of the SD system. Temperature data for the SD system was collected during the experiment and used to validate a numerical finite element analysis model. This study shows that the SD system was able to achieve a fire resistance rating of 57 min in the experiment which was governed by insulation resistance. A lower fire resistance rating is estimated based on numerical models. Structural resistance was maintained throughout the test. During preliminary testing structural collapse was observed in a separate experiment which highlights how the system is sensitive to damage to the ceiling boards. Numerical results highlight that thermal bowing and movement may result in changes in thermal interactions between adjacent elements. This paper provides novel large-scale experimental data on a loaded flooring system in fire.

Firefighters’ or instructors’ exposure to airborne chemicals during live-fire training may depend on fuels being burned, fuel orientation and participants’ location within the structure. This study was designed to evaluate the impact of different control measures on exposure risk to combustion byproducts during fire dynamics training where fuel packages are mounted at or near the ceiling. These measures included substitution of training fuels (low density wood fiberboard, oriented strand board (OSB), pallets, particle board, plywood) and adoption of engineering controls such as changing the location of the instructor and students using the structure. Experiments were conducted for two different training durations: the typical six ventilation cycle (six-cycle) and a shorter three ventilation cycle (three-cycle) with a subset of training fuels. In Part A of this series, we characterized the fire dynamics within the structure, including the ability of each fuel to provide an environment that achieves the training objectives. Here, in Part B, airborne chemical concentrations are reported at the location where fire instructors would typically be operating. We hypothesized that utilizing a training fuel package with solid wood pallets would result in lower concentrations of airborne contaminants at the rear instructor location than wood-based sheet products containing additional resins and/or waxes. In the six-cycle experiments (at the rear instructor location), OSB-fueled fires produced the highest median concentrations of benzene and 1,3 butadiene, plywood-fueled fires produced the highest total polycyclic aromatic hydrocarbon (PAH) concentrations, particle board-fueled fires produced the highest methyl isocyanate concentrations, and pallet-fueled fires produced the highest hydrogen chloride concentrations. All fuels other than particle board produced similarly high levels of formaldehyde at the rear instructor location. The OSB fuel package created the most consistent fire dynamics over six-cycles, while fiberboard resulted in consistent fire dynamics only for the first three cycles. In the follow-on three-cycle experiment, PAH, benzene, and aldehyde concentrations were similar for the OSB and fiberboard-fueled fires. Air sampling did not identify any clear differences between training fires from burning solid wood pallets and those that incorporate wood-based sheet products for this commonly employed fuel arrangement with fuels mounted high in the compartment. However, it was found that exposure can be reduced by moving firefighters and instructors lower in the compartment and/or by moving the instructor in charge of ventilation from the rear of the structure (where highest concentrations were consistently measured) to an outside position.

Certain groups (e.g., those of higher age, lower educational attainment, lower income, living alone, immigrants, etc.) have a greater risk of residential fire mortality. Previous research has also shown that individuals belonging to high-risk groups have generally lower levels of fire protection, and it has been suggested that this is due to a lower risk perception in this group. As such, this study investigates how the perceived risk of being injured in a residential fire varies in the Swedish population. The results show that risk perception varies in the Swedish population depending upon sociodemographic factors. When the different sociodemographic factors are controlled against each other, women, individuals with a low educational level, individuals living in rural communities and individuals born outside of the Nordic countries consistently experience their risk to be higher. With the exception of women, the results show that high-risk individuals have a high risk perception. These results are important as they indicate that it is not a lack of risk awareness that is the reason why high-risk groups are less inclined to implement fire safety practices.

Wall restriction is an important factor affecting flame space development, air entrainment and heat transfer. To investigate the smoke characteristics in the one-dimensional horizontal spreading stage at different transverse fire locations in tunnel, FDS was used to simulate and analyze the smoke mass flow rate. The results show that the average smoke mass flow rate is positively correlated with distance from fire source to sidewall and heat release rate (HRR). The maximum smoke temperature rises decay exponentially along the longitudinal direction of the tunnel. Based on dimensional analysis, a prediction model is proposed to predict the average smoke mass flow rate in one-dimensional horizontal spreading stage in tunnel. For wall fires, predicted mass flow rate is 1.29 times of Zukoski model via generalizing the "mirror" effect. For non-wall fires, the dimensionless smoke mass flow is proportional to the 0.19 power of the dimensionless HRR. Besides, the reliability of the prediction model is verified by comparing with full-scale and reduced-scale experiments.

This gait biomechanics study investigated stride length (SL), stride duration (SDN), the peak values of ground reaction forces (GRFspeak), required coefficient of friction (RCOFpeak), leg joints’ angles (anglepeak), angular velocity (angvelx.peak), angular acceleration (angaccx.peak), minimum angle (anglemin.) of the foot, and muscles’ electromyography (EMG) during the stance phase (SP) of the dominant leg following an exhaustive stair ascent on a stair machine. Data were collected by a three-dimensional motion capture system synchronized with EMG and force plate while walking down a 10° inclined stationary walkway. Although the leg muscles’ EMG showed no significant local muscle fatigue (LMF) during post-exhaustive walking downwards, the SL was significantly (p < 0.05) shorter than the pre-exhaustive. The mean vertical GRFzpeak. was significantly (p ≤ .01) reduced during late stance (LS) phase, however, the antero-posterior GRFypeak. was found to be significantly (p ≤ 0.01) higher. The RCOFpeak. was significantly (p ≤ .05) higher during the post-exhaustive walking downwards, LS phase. The available coefficient of friction value of ~ 0.350 seems to be the RCOF to reduce slips and falls on an inclined dry surface. None of the post-exhaustive lower limb joints’ anglepeak, anglemin., ang.velx.peak, and ang.accx.peak were significantly changed in post-exhaustion walking, except the knee ang.accx.peak., which was significantly (p < 0.05) increased during the LS period. The constrained post-exhaustive gait biomechanics indicate a perturbed gait, which may increase the risks for slips and fall-related accidents, when walking downwards and working on slopes. However, the non-significant joint angle changes imply that walking down is less demanding in a kinesiological perspective compared to walking up an incline.

The problem of fires in informal settlements has been recognized as a global phenomenon, affecting thousands of people annually and representing an extreme risk for millions. Informal settlements are characterized by poor infrastructure, lack of access to essential services and dwellings built from flammable materials. Their vulnerability to fire is extreme as even where losses are minimal fires ruin lives, damage property, and undermine socioeconomic development. Currently, there is a great need to understand the proportion and characteristics of the problem around the world. As an attempt to help fill this knowledge gap, this paper presents a detailed description of the problem of informal settlement fires in Colombia. This investigation includes the contextualization of the problem, a morphological description of several common dwelling types, and their socio-economic characteristics in terms of the number of people, physical conditions, and provision of services. The statistics associated with informal settlement fires in Colombia are reported, with emphasis on the number of dwellings destroyed, people affected, ignition sources and challenges for fire suppression operations. Finally, a case study highlighting the development of a typical informal settlement fire in Colombia is presented. The results reported in this paper are suitable to support emergency protocols and prevention strategies aiming to mitigate the risk associated with informal settlements.

Building fires are one of the most common fire types and tend to cause heavy casualties. During the evacuation, the shortest path makes the escapees leave the accident scene faster. Meanwhile, the safety of escapees in the evacuation process cannot be ignored. Optimal path should both ensure evacuation efficiency and maximize the safety of escapees. A bi-objective path planning model, which considers both path risk and path length, is presented. Path risk is based on five risk factors that are likely to cause casualties in a fire: carbon monoxide (CO), hydrogen cyanide (HCN), temperature, visibility, and crowding. The linear weighted sum method is used to convert the risk-objective model and the length-objective model into a dynamic bi-objective path planning model. The Dijkstra algorithm is modified to solve the model. The modified algorithm outperforms the traditional Dijkstra algorithm in terms of both efficiency and adjustment ability. The simulation analysis of a building fire shows that the bi-objective model and algorithm can plan a combined optimal evacuation path for escapees considering risk and path length, which avoids the area with high risk level and optimizes the evacuation path length.

Thatched rooves are exist all over the world and a common challenge is fire safety. There are many reports that complete villages burned down in the middle ages. In the early modern period, administrations started imposing urban building regulations and the use of non-combustible materials such as ceramic tiles and metal on the rooves became spread wide in rural areas. As a result, the thatched roof is becoming rare. On the other hand, the thatched roof and its supply source, prairie, have been re-evaluated in modern times contributing to 20% of total carbon dioxide fixation. Moreover, it helps to nurture biodiversity and a sustainable society. In this paper, the current building regulations concerning on thatched rooves are compared between the UK, Denmark, the Netherlands and Japan. It has been found that some distance is required from the boundary and the installation of fire resistant boards underneath the thatch as a fire barrier are common in Europe. On the other hand, zoning system and water cannons are used against firebrand in Japan. By categorizing these fire prevention methods, concepts and evaluation methods in each method became clearer. At first, the concept of fire prevention on the roof needs to be considered. If it is difficult to achieve by any one of noncombustibility of materials, distance, water cannon or fire retardant coating, then fire prevention inside the house is considered next. Also, fire prevention to neighboring house is only considered by restriction of linings for existing regulations, but prevention of fire spread due to ejected window flames also needs to be considered in case that a thatched roof located close to a neighboring house. And the following missing pieces were measured to expand the range of application in each method to all the other countries. The critical heat flux for Japanese plant materials was measured in Cone calorimeter test to apply the European concept, distance, to Japan. The value was 10–15 kw/m2, and it was validated by a real fire investigation. And the heating temperature to a secondary layer in the European membrane system was measured to be able to estimate the necessary thickness of a Japanese clay roof as the fire barrier. A cost-effective drencher system outside the thatched roof originating from the Japanese snow melting system is also proposed. A water flow of 3.5 L/m/min successfully prevented fire spread on thatched rooves in an ISO 12468 test and a firebrand shower exposure experiment. In addition, a non-combustible eave consisted of a noncombustible window overhang under the thatched roof was evaluated using window flame.

Concern for the health of the natural environment is growing as human population grows. Recently, renewed attention has been given to the environmental impact of fires and the fire implications of sustainability choices made in the built environment. To properly understand the environmental impact of fires, however, it is crucial that we can estimate fire emissions. This paper explores the concept of fire emissions and emission factors and investigates the potential to use small scale testing to develop emission factors for fire emissions. The findings show that there is a potential to use dynamic tests such as the cone calorimeter (CC, ISO 5660) and fire propagation apparatus (FPA, ISO 12136) to develop emission factors to estimate larger scale fire emissions, at least for CO and CO2 emissions. While there is a spread of data from between the CC or FPA and the medium scale tests, this is of the same order or less than the spread between the two small scale tests. The spread in emission factor values from the various tests is smaller for CO2 than for CO and greatest for small CO-emission factors (< 10 g/kg). More work is needed to similarly characterise a broad range of species.

Structural steel, when exposed to fire, loses its tensile strength and ability to resist deformation. Both organic and inorganic material-based passive fire protection systems, are being traditionally used to protect steel structures in such scenarios. This study focused on comparing the performance of the same organic and inorganic coatings in standard fire, hydrocarbon fire, and jet fire conditions. Standard, hydrocarbon fire, and jet fire experiments were carried out in full-scale fire resistance furnaces as per ASTM E-119, UL 1709, and ISO 22899-1 respectively. From the results, it was observed that both organic and inorganic materials tend to underperform in jet fire scenarios, when compared with standard and hydrocarbon fire due to the impingement/turbulence effect and the thermo-mechanical effect caused by the velocity of the gas.