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Mass rapid transit (MRT) systems are the backbone of transportation infrastructure in many cities. During emergencies, indoor subway stations become particularly susceptible to panic and overcrowding, making evacuation difficult. Therefore, simulating the evacuation and sheltering processes of a large number of individuals during emergencies is key in urban disaster response. In this study, a spatial evacuation risk model was used to enhance the safety of evacuation strategies in an MRT system. Data were collected on spatial architectural floor plans, and a database for communication and pedestrian flow was established. The behavioral patterns and distribution of individuals within stations and the characteristics of refuge spaces were also investigated. To simulate the processes of evacuation and sheltering, the Pathfinder evacuation simulation tool was used to construct a three-dimensional spatial model of a subway station. Specific scenarios were then constructed to simulate the procedures of evacuation and sheltering. Subsequently, the factors contributing to overcrowding-related hazards were analyzed to examine the spatial risks associated with crowd aggregation and evacuation and provide recommendations for improvement. Given its numerous advantages, this approach can serve as a valuable reference for conducting risk assessments in other large-scale crowd aggregation spaces. [ABSTRACT FROM AUTHOR]

Slope instability due to tectonic, hydrological and anthropogenic activities cause severe landslides in Himalaya. Joshimath, a densely populated Himalayan town witnessed a catastrophic landslide event during December 2022 and January 2023 causing damages to ∼700 buildings. We use Interferometric synthetic aperture radar, Global Positioning System and rainfall measurements to probe the kinematics of the Joshimath landslide. We separate the seasonal and episodic deformation components using singular spectrum analysis. While the low amplitude annual landslide motions are modulated by seasonal precipitation, acceleration phases are triggered by extreme rain events. Our analysis revealed episodes of cascading motions triggered by extreme rain events resulting an overall increase in landslide velocity from −22 mm/yr during 2004–2010 to −325 mm/yr during 2022–2023. We estimate the landslide depth (∼30 m) and hydraulic diffusivity (∼3 × 10−5 m2/s) using a 1‐D pore‐water pressure diffusion model. Our study reveals the importance of systematic monitoring of ground deformation and weather parameters for landslide hazard mitigation. Plain Language Summary: The Himalayas, world's largest and youngest mountain range formed as a result of the India‐Eurasia continental collision hosts thousands of landslides each year related to tectonic and anthropogenic activities. It is important to characterize the landslide kinematics, especially the slow moving landslides at the fast‐developing Himalayan urban centers for hazard assessment. A recent catastrophic landslide event in the Joshimath town in NW Himalaya occurred between December 2022 and January 2023 caused damages to ∼700 buildings leading to mass evacuation. We map the spatio‐temporal evolution of land deformation at Joshimath using about two decades of geodetic measurements and singular spectrum analysis technique. While the decadal‐scale landslide motions match well with the overall increase in rainfall intensity, the episodic accelerations are triggered by extreme rain events. The extreme rainfall event on 19 October 2021, triggered the latest episode of landslide acceleration, which eventually led to the tragic disaster. The present study, for the first time, provides constraints on the landslide depth and hydraulic diffusivity. Our study also emphasis on the systematic monitoring of ground deformation and weather parameters at the Himalayas for an effective landslide hazard preparedness and mitigation. Key Points: Joshimath landslide displays episodic and seasonal kinematic changes; episodic accelerations are triggered by extreme rain eventsThe 19 October 2021 extreme rain event triggered the latest episode of landslide acceleration culminating to the 2022 disasterDepth and hydraulic diffusivity of the landslide is constrained using 1‐D pore‐water pressure diffusion model [ABSTRACT FROM AUTHOR]

The traditional storage method of fire accident cases is mainly in the form of text, and it is difficult to effectively conduct comprehensive analysis due to the limited ability to display key information and fire knowledge. In this paper, a structured storage form of building fire cases was proposed based on knowledge graph, which can comprehensively describe and visualize the fire causes, the dynamic fire development process and evacuation process. It enables readers to get information and knowledge from building fire cases intuitively, and supports the comprehensive analysis for building fire prevention strategies. The knowledge graphs are constructed for two common building types (residential and public buildings), and have the capacity to reflect the dynamic development law of fires from ignition to spread in different buildings. Meanwhile, as the occupants' evacuation is the first concern when a fire occurs, the knowledge graphs also visualize the relationship among various conditions in the evacuation process. Different application scenarios are displayed in the paper, including case query, root-cause analysis and consequence forecasting, which shows the advantages and applicability of building fire knowledge graph. [ABSTRACT FROM AUTHOR]

In order to ensure the safety of life and property in large buildings, the design of emergency evacuation routes for large buildings based on cloud computing and GIS big data is studied. Combining cloud computing and GIS big data, a command model for emergency evacuation of large buildings is built. Emergency evacuation functions are realized through the access layer, business logic layer, cloud computing layer and data layer. GIS big data of large buildings is stored in the model data layer. GIS geographic data is clustered through the MapReduce based parallel K-means clustering algorithm in the cloud computing layer. After clustering, the emergency evacuation road network of large buildings is constructed through GIS in the business logic layer. On the road network, the emergency evacuation route selection method combining Dikstra algorithm and ant colony algorithm is used to realize the optimal route selection of emergency evacuation of large buildings. Experiments show that this method can effectively select the best evacuation path in large buildings, and the evacuation speed of the selected path is fast, which can ensure the safety of people in buildings. [ABSTRACT FROM AUTHOR]

This paper improves the visual change-based personnel evacuation model by considering the evacuees' gravity. Specifically, first, the new model incorporates the gravity formula in the model's mechanic part to consider the influence of gravity. Second, the new model involves rules for determining the visual range of personnel moving in the stairwell. Third, the proposed model investigates the influence of the angle and width of the stairwell, the number of people, and other factors during personnel evacuation under the influence of gravity. The model is developed in Python and is compared with actual results, revealing that the proposed model is more realistic considering the evacuation time compared to current models. Indeed, under a fixed number of people, when the stairwell angle is less than 34°, the evacuation time decreases as the angle increases, and when the stairwell angle exceeds 34°, the evacuation time is almost unchanged. Additionally, under a fixed number of evacuees, the evacuation time decreases as the width of the stairwell increases, and due to stairwell width space redundancy, the evacuation time tends to stabilize. The results of the new model research provide reference for the design of building safety evacuation, thereby improving the safety of buildings. [ABSTRACT FROM AUTHOR]

In South Korea, the need to link fire and evacuation simulations to compare the available safety egress time (ASET) and required safety egress time (RSET) in real time when implementing performance-based design in buildings is increasing. Accordingly, the Consolidated Model of Fire Growth and Smoke Transport (CFAST) has been discussed as an alternative to the fire dynamics simulator, which requires high computational costs, sufficient experience in fire dynamics numerical calculations, and various input parameters and faces limitations in integration with evacuation simulations. A method for establishing a reasonable computational domain to predict the activation times of smoke and heat detectors has been proposed. This study examined the validity of using CFAST to predict factors relevant to the ASET evaluation. The results showed that CFAST, which solved empirical correlations based on heat release rates, predicted high gas temperatures similarly. Moreover, the applicability of the visibility distance calculation method using smoke concentration outputs from CFAST was examined. The results suggest that despite the limitations of the zone model, CFAST can produce reasonable ASET results. These results are expected to enhance the usability of CFAST in terms of understanding general fire engineering technology and simple fire dynamics trends. [ABSTRACT FROM AUTHOR]

A calamitous landslide happened at 22:00 on September 1, 2014 in the Yunyang area of Chongqing City, southwest China, enforcing the evacuation of 508 people and damaging 23 buildings. The landslide volume comprised 1.44 million m3 of material in the source area and 0.4 million m3 of shoveled material. The debris flow runout extended 400 m vertically and 1600 m horizontally. The Xianchi reservoir landslide event has been investigated as follows: (1) samples collected from the main body of landslide were carried out using GCTS ring shear apparatus; (2) the parameters of shear and pore water pressure have been measured; and (3) the post‐failure characteristics of landslide have been analyzed using the numerical simulation method. The excess pore‐water pressure and erosion in the motion path are considered to be the key reasons for the long‐runout motion and the scale‐up of landslides, such as that at Xianchi, were caused by the heavy rainfall. The aim of this paper is to acquired numerical parameters and the basic resistance model, which is beneficial to improve simulation accuracy for hazard assessment for similar to potentially dangerous hillslopes in China and elsewhere. [ABSTRACT FROM AUTHOR]

Earthquake simulations at the urban scale usually focus on estimating the damages to the built environment and the consequent losses without fully taking into account human behavior in crisis. Yet, human behavior is a key element for improving crisis disaster management; therefore, it is important to include it in seismic crisis simulations. In this study, an agent-based model for the simulation of pedestrian evacuation during earthquakes at the city scale is developed following an interdisciplinary approach. The model recreates the urban conditions using Geographic Information System (GIS) and a synthetic population, in addition to the earthquake consequences on the urban fabric. Moreover, the model integrates realistic human behaviors calibrated using quantitative survey results. We simulate pedestrian outdoor mobility with the different constraints that affect it such as the topography and the presence of debris. The simulator is applied to the case of Beirut, Lebanon. A what-if approach is adopted to analyze the population's safety in case of earthquakes in Beirut, particularly the open spaces' capacity to provide shelters and the effect of debris and realistic human behaviors on people's safety. The simulation results show that less than 40% of the population is able to arrive at an open space within 15 min after an earthquake. This number is further reduced when some open spaces are locked. Debris and realistic human behaviors significantly delay the arrivals to safe areas and, therefore, should not be neglected in earthquake simulations. [ABSTRACT FROM AUTHOR]

The cellular automata (CA) model has been a meaningful way to study pedestrian evacuation during emergencies, such as fires, for many years. Although the time step used in the CA model is one of the most essential elements, there is a lack of research on its impact on evacuation time. In this paper, we set different time step sizes in an extended cellular automaton model and discuss the effect of time step size on the overall evacuation time under different emergency types and levels. For a fixed step time mode, the larger the time step, the longer the evacuation time. In each time step size, the evacuation time gradually increases with the increase of emergency level, and there is a sharp increase when the time for pedestrians to move one step is exactly an integer multiple of the time step. When there is no friction between pedestrians, the evacuation time at each time step first decreases slightly with the increase of emergency level and then remains unchanged; the larger the time step, when the evacuation time remains unchanged, the lower the emergency level and the greater the evacuation time. For the variable time step model, when the friction between pedestrians approaches infinity, the total evacuation time does not change with the emergency level; when the friction between pedestrians is reduced, the total evacuation time slightly decreases with the increase of the emergency level. The less friction there is, the more significant the reduction. The results of previous actual experiments are also reflected in the simulation at a lower emergency level. The result shows that the time step size significantly impacts the evacuation simulation results of the CA model, and researchers should choose carefully to obtain more realistic simulation results. [ABSTRACT FROM AUTHOR]

This paper presents the critical egress parameters that influence emergency evacuation in a typical hospital building. A parametric study of a 20-story hospital building is conducted using a computer model "Pathfinder" to simulate the evacuation efficiency and assess the influencing parameters. The main egress parameters that influence the evacuation efficiency, including the location of stairways, number of stairways, location of the fire, exit width, and number of low-speed occupants are varied. Two scenarios are simulated: one being the regular (practice) evacuation drill and the other is the actual fire drill. The result shows that the location of stairways significantly affects the total evacuation time with the optimal stairway arrangement consisting of one stairway outside the core of the building. Similarly, the story level at which the fire occurs is another key parameter with fires at lower levels being critical to dictating the evacuation time in a hospital building. The total evacuation time when the fire occurs between the third and sixth floor is found to be 170 min which is 36% and 15% higher than fires at the top story levels (15–18th floor) and the intermediate story levels (9–12th floor), respectively. [ABSTRACT FROM AUTHOR]

This paper describes the analysis of electrodermal activity (EDA) in the context of students' scholastic activity. Taking a multidisciplinary, citizen science and maker-centric approach, low-cost, bespoken wearables, such as a mini weather station and biometric wristband, were built. To investigate both physical health as well as stress, the instruments were first validated against research grade devices. Following this, a research experiment was created and conducted in the context of students' scholastic activity. Data from this experiment were used to train machine learning models, which were then applied to interpret the relationships between the environment, health, and stress. It is hoped that analyses of EDA data will further strengthen the emerging model describing the intersections between local microclimate and physiological and neurological stress. The results suggest that temperature and air quality play an important role in students' physiological well-being, thus demonstrating the feasibility of understanding the extent of the effects of various microclimatic factors. This highlights the importance of thermal comfort and air ventilation in real-life applications to improve students' well-being. We envision our work making a significant impact by showcasing the effectiveness and feasibility of inexpensive, self-designed wearable devices for tracking microclimate and electrodermal activity (EDA). The affordability of these wearables holds promising implications for scalability and encourages crowd-sourced citizen science in the relatively unexplored domain of microclimate's influence on well-being. Embracing citizen science can then democratize learning and expedite rapid research advancements. [ABSTRACT FROM AUTHOR]

Walking speed is a significant aspect of evacuation efficiency, and this speed varies during fire emergencies due to individual physical abilities. However, in evacuations, it is not always possible to keep an upright posture, hence atypical postures, such as stoop walking or crawling, may be required for survival. In this study, a novel 3D passive vision-aided inertial system (3D PVINS) for indoor positioning was used to track the movement of 20 volunteers during an evacuation in a low visibility environment. Participants' walking speeds using trunk flexion, trunk–knee flexion, and upright postures were measured. The investigations were carried out under emergency and non-emergency scenarios in vertical and horizontal directions, respectively. Results show that different moving directions led to a roughly 43.90% speed reduction, while posture accounted for over 17%. Gender, one of the key categories in evacuation models, accounted for less than 10% of the differences in speed. The speeds of participants under emergency scenarios when compared to non-emergency scenarios was also found to increase by 53.92–60% when moving in the horizontal direction, and by about 48.28–50% when moving in the vertical direction and descending downstairs. Our results also support the social force theory of the warming-up period, as well as the effect of panic on the facilitating occupants' moving speed. [ABSTRACT FROM AUTHOR]

Safety accidents frequently occur in university laboratories, making the evacuation of students from multiple exits a critical issue. In order to address this concern, we utilized the AnyLogic software to simulate a university laboratory environment. By quantifying the degree of awareness, representing safety education, safety training, and familiarity, we enhanced the expected speed within the primary social force model. Expanding on this foundation, we investigated various exit layouts and conducted experiments to develop an optimization scheme that evenly distributes exit locations and improves exit width. The objective of this approach was to resolve the problem of imbalanced utilization rates in multi-exit laboratories. The simulation results demonstrate that increased awareness not only enhances students' expected speed but also reduces evacuation time. Moreover, by implementing appropriate exit spacing and width settings, we were able to not only evenly distribute students but also alleviate congestion at exits, effectively resolving the issue of imbalanced exit utilization. [ABSTRACT FROM AUTHOR]

When the Conservative Member of Parliament and Leader of the House of Commons Jacob Rees-Mogg complained on London's LBC radio that the 72 victims of the 2017 Grenfell fire did not use common sense and simply leave the building, and that he could not understand how it had 'anything to do with race or class', he fell into a trap which is now at least 150 years old. This has seen the art and act of evacuating – especially tall buildings – blamed on the evacuees themselves. It is also revealing of an aesthetics of erasure which silences a classed, raced and gendered politics which has served to render certain subjects and bodies as not only victims, but culpable. The vertical evacuee has been considered too slow, too big, too indecisive, too passionate, too weak, too much, too many – too inadequate. In this paper, and in building on a wider politics of verticality and mobility, I pull on several threads of the gendered and raced geographies of high-rise vertical evacuation focusing particularly on the solidaristic movements and expressions of the workers. The paper explores the history of tall building evacuations, focusing on early high-rise factory fires, their investigation, and subsequent changes to fire regulation, building technologies and working practices in North America which affected predominantly young, female and migrant working labour. [ABSTRACT FROM AUTHOR]

The construction of hydrogen refueling stations (HRSs) is crucial in supporting the comprehensive popularization of hydrogen energy. However, many countries have difficulties expanding hydrogen infrastructure due to the high risk of hydrogen. In this work, a Computational Fluid Dynamics three-dimensional model is combined with individual lethality probability models to study the consequences of a leak explosion at the main components within a HRS. Two new canopies of hydrogen dispensers are designed to improve hydrogen evacuation efficiency. Results indicate that the safety distance based on the individual risk between the main equipment in the station can be reduced by 21.7%–67.0% compared with the actual layout distance. And the safety distance between dispensers, which is not specified in Chinese standards, is proposed to be 6.8 m. When the inclination angle of the dispenser canopy does not exceed 15° and the width does not exceed 12 m, the hydrogen leaking from the top of the dispenser has the smallest retention volume. Moreover, the tube trailers are advised to avoid parking in HRSs due to the increased consequences of explosive accidents. [Display omitted] • Various leakage and explosion accident scenarios of main components in HRS are analyzed. • The safety distance between the main components based on individual risk can be further reduced. • Two newly designed canopies significantly improve the hydrogen evacuation efficiency. • Effect law of long tube trailers on the explosion hazard range and overpressure peak is obtained. [ABSTRACT FROM AUTHOR]

Kamaishi in Iwate Prefecture has suffered devastating damage on several occasions, including the 1896 Meiji Sanriku tsunami, the 1933 Showa Sanriku tsunami, the 1945 naval bombardment during W.W. II and the 2011 Great East Japan Earthquake. Each time, the city has recovered. This paper explores the history of reconstruction planning and urban development in Kamaishi and how the city's landscape and urban space have been shaped by disaster and reconstruction. In the Kamaishi area in modern times, temples, shrines and public facilities have been moved and new infrastructure has been developed repeatedly, after each disaster. The accumulated reconstructions have generated a landscape in which the city is centred on wide streets that form a vertical axis connecting the coast and the highlands. The need to evacuate has been woven into the urban space of Kamaishi through repeated experiences of disaster and reconstruction. In the reconstruction that took place after the Great East Japan Earthquake, new layers and facilities were added for commercial recovery and residential reconstruction, but the underlying intention was to build a network of evacuation routes. [ABSTRACT FROM AUTHOR]

Musculoskeletal disorders are prevalent in the construction industry, particularly among masons who are at risk of overexertion and back injuries due to the physical demands of their jobs. Previous research established that expert masons employ different work strategies that reduce joint loads and increase productivity; however, it was unclear which movement strategies they used. This study analyzed the movements of novice, apprentice, and expert masons to identify their postural characteristics. Specifically, the postures and motions of novice, apprentice, and expert masons are analyzed during a standard wall building activity using concrete masonry units, and the key markers of their techniques, such as trunk flexion and twisting, are investigated. Our findings describe the movement strategies experts use in comparison to inexpert groups. Through the analysis of expert motion techniques, the intrinsic movement knowledge of expert masons can be translated into numeric joint thresholds and coaching feedback for training programs. [ABSTRACT FROM AUTHOR]

In structural health monitoring (SHM), most current methods and techniques are based on the assumption of linear models and linear damage. However, the damage in real engineering structures is more characterized by nonlinear behavior, including the appearance of cracks and the loosening of bolts. To solve the structural nonlinear damage diagnosis problem more effectively, this study combines the autoregressive (AR) model and amplitude-aware permutation entropy (AAPE) to propose a data-driven damage detection method. First, an AR model is built for the acceleration data from each structure sensor in the baseline state, including determining the model order using a modified iterative method based on the Bayesian information criterion (BIC) and calculating the model coefficients. Subsequently, in the testing phase, the residuals of the AR model are extracted as damage-sensitive features (DSFs), and the AAPE is calculated as a damage classifier to diagnose the nonlinear damage. Numerical simulation of a six-story building model and experimental data from a three-story frame structure at the Los Alamos Laboratory are utilized to illustrate the effectiveness of the proposed methodology. In addition, to demonstrate the advantages of the present method, we analyzed AAPE in comparison with other advanced univariate damage classifiers. The numerical and experimental results demonstrate the proposed method's advantages in detecting and localizing minor damage. Moreover, this method is applicable to distributed sensor monitoring systems. [ABSTRACT FROM AUTHOR]

The detail and representation of a spatial layout varies with scale. This affects an individual's learning effectiveness and understanding, in turn directly influencing their behavior in a fire evacuation. However, the impact of layout learning methods with different spatial scales on fire evacuation behavior, and the relationship between spatial cognition and evacuation effects, remains unclear. We conducted spatial layout learning across three scales with 81 participants and simulated a fire evacuation scenario in a mobile virtual reality for groups. We collected evacuation decision-making and user experience questionnaires as . The results demonstrate that small-scale learning objects are the easiest for participants to understand in terms of spatial layout and relationships, but their performance in fire evacuation is poor. Large-scale learning objects significantly improve participants' evacuation efficiency. Spatial layout learning plays a crucial role in fire evacuation outcomes, but traditional spatial knowledge acquisition measurement methods cannot predict fire evacuation performance. This study sheds light on how spatial cognition influences fire evacuation behavior and provides a more reliable fire evacuation simulation method based on mobile virtual reality (MVR). [ABSTRACT FROM AUTHOR]

The complexity in nonlinear behavior of torsional-irregular buildings in combination with uncertainty due to the natural randomness of earthquake records has been always a main challenge for buildings' seismic design. To find a solution to this challenge, three reinforced concrete (RC) building archetypes were designed and next developed into their nonlinear models. Nonlinear static (pushover) analyses were performed to calculate the capacity of the archetype models in all principal and non-principal directions while incremental dynamic analyses (IDAs) were conducted by applying 30 accelerograms from both near-field and far-field earthquakes. The IDA capacity curves, collapse fragility curves and log-normal cumulative distribution functions (CDFs) were established by including both the aleatory randomness and epistemic uncertainty. Despite previous studies wherein fragility curves were given by evaluating structures' collapse along structural reference axes or simply on x , y -axes, in this paper, possible building collapse on a critical non-principal direction (where maximum seismic response was observed) was simulated and its probability was accounted for developing IDA curves and log-normal CDFs. Accordingly, this issue was mirrored in computing available/acceptable collapse margin ratios (CMRs). In addition to the well-known outline used for calculating CMRs in the literature (that is based on estimation of collapse capacity in terms of earthquake intensity measure (IM)), the framework proposed here includes a new method for calculating the CMRs in terms of displacement-based drift, ductility, and damage. The superiority of the proposed method over the former is consistent with the buildings' design procedure that is governed by storey drift control rather than base-shear strength. Refined statistics of CMRs given by taking into account displacement-based responses illustrate the available CMRs exceed the acceptable CMRs, meaning that a satisfactory safety margin against collapse will be anticipated in the targeted building class if a suitable yielding mechanism with sufficient ductility is provided for seismic force-resisting system by applying seismic design provisions of the current codes. [ABSTRACT FROM AUTHOR]

Religiosity potentially has a significant economic impact in Australia, but we do not currently have a good understanding of that impact. Research sponsored by the research project called 'The Study for the Economic Impact of Religion on Society' (SEIROS) has sought to capture, in part, the role religiosity plays in contributing to economic life in Australia by measuring how religious commitment enhances volunteering and donation behaviour. That research focuses on an individual's commitment rather than their institutional engagement with religious organisations. Based on a survey of religious engagement, and building on the approach of Lyons and Nivison-Smith (2006), SEIROS engaged Deloitte Access Economics (DAE) to build a logistic regression model which captured a positive impact of religiosity on volunteering and giving, measured by comparing persons coming to faith in adult life against people who never identify as being religious. However, this article argues that the DAE study suffers from the limitation of measuring religiosity as a 'treatment effect' captured by conversion in adult life and excludes the cohort of persons who have been religious since youth. As a result, the impact of religious engagement on giving of time and money may be understated. [ABSTRACT FROM AUTHOR]

With the acceleration of urbanization, the frequency of building fire incidents has been increasing year by year. Therefore, rapid, efficient, and safe evacuation from buildings has become an urgent and important task. A construction fire escape path planning method based on an improved NavMesh algorithm is proposed in this paper. Firstly, by using the method of local updates in the navigation grid, redundant computation is reduced, and the update time of the improved algorithm is about 6.8% of that of the original algorithm, immediate generation of navigation is achieved. Secondly, the heuristic function of the pathfinding algorithm is improved, and a multi-exit path planning mechanism is proposed to achieve more efficient, which can quickly plan a safe evacuation path away from the spreading fire and smoke in the event of a fire. Finally, a new evaluation index called Navigation Grid Complexity (NGC) is proposed and demonstrated to measure the quality of navigation grids. The feasibility and effectiveness of the proposed method are validated through simulation experiments on actual building models, which can provide real-time, efficient, intelligent, and safe path planning for rapid evacuation of evacuees in the fire scene. [ABSTRACT FROM AUTHOR]

In this study, based on a real fire in an object intended to produce electricity, the method of fire extinguishing by fire protection units with components of the Integrated Rescue System was characterised. The goal was to examine the effectiveness of extinguishing the mentioned type of fire in cooperation with other components of the Integrated Rescue System and the effectiveness of the intervention, where the priority task was the rescue of people from a fire-endangered building with forces and resources deployed in the vicinity of the fire. In the study, the time factor of the arrival of individual components, material and technical equipment, and security was also considered and, based on calculations, the possibilities of the starting units to extinguish the fire and ensure the evacuation of people in the building. Subsequently, after evaluating and examining all possibilities, conclusions were chosen and determined from the results at the place of the intervention and recommendations were defined for future fires in similar objects. [ABSTRACT FROM AUTHOR]

Previous tsunami numerical model results show that the 1755 tsunami reached the Figueirinha beach 35 min after the earthquake, resulting in the inundation of the beach, the parking lot, and two sections of the road on the beach. Thus, an effective evacuation plan for the beach must be identified. However, conducting drills and evacuation exercises is costly and time-consuming. As an alternative, this study develops an agent-based model (ABM) to simulate the evacuation of beach users. The findings from this study reveal that, across the six considered scenarios, it is not feasible to evacuate all beach users in less than 35 min. The results also show there are only two routes available for evacuation—the left and right sides—with the left side offering a shorter evacuation time. However, both evacuation options come with advantages and disadvantages. The results of this study will be disseminated to local stakeholders. [ABSTRACT FROM AUTHOR]

Exit signs are intended to help occupants promptly and accurately select evacuation paths during emergencies. However, according to previous studies and accident cases, exit signs are not helpful for occupants during emergency situations, which can be attributed to limited visibility due to the smoke generated during fires. Further, most exit sign installation standards do not consider exit sign visibility in smoke-filled environments. Thus, exit sign visibility can be considered to be low during actual fires. To overcome this issue, a means of improving visibility was investigated in this study by changing the exit sign color. A full-scale experiment was conducted to analyse the maximum cognitive distance (The maximum cognitive distance is defined as the greatest distance at which an observer can clearly identify the content of an exit sign) according to the exit sign safety colour in which a smoke-filled environment was simulated using a translucent eye patch. The smoke-filled environment was divided into nine levels of obstructed visibility according to the visibility distance when a translucent eye patch was worn. The maximum cognitive distance was measured for exit signs in seven safety colours (red, orange, yellow, green, blue, navy, and purple). The results showed that the mean maximum cognitive distances of the navy, purple, blue, and red exit signs were greater than that of the green exit sign, which is widely used currently. The navy, purple, blue, and red exit signs had mean maximum cognitive distances approximately 1.29 times, 1.23 times, 1.22 times, and 1.21 times longer than that of the green exit sign, respectively. The differences in the mean maximum cognitive distance were found to be statistically significant at a level of 0.05. This study's analysis showed that these four colours had a greater contrast effect on the background colour (white) than green. Hence, the contrast difference between the safety colour and the background colour is considered the main parameter affecting cognitive performance for the exit sign lighting. [ABSTRACT FROM AUTHOR]

There are currently efforts to inform the public of the fire safety benefits of keeping bedroom doors closed when occupants are sleeping. A closed door can provide a substantial advantage to sleeping occupants of a bedroom in the event of a fire by hindering the spread of heat and toxic gases. The overall benefit in this arrangement is clear when occupants have interconnected smoke alarms inside and outside the sleeping areas as detection and notification of the fire is not hindered by a closed door. Concerns have arisen for situations when such a detection and notification arrangement is not present in the residence and the door can act as an obstacle for rapid detection and notification of occupants. Calculations and data from the fire science literature were used to evaluate the effect of a closed bedroom door on the number of unsuccessful evacuation outcomes that may result from fires originating in the bedroom, as well as the effect of a closed bedroom door on the audibility of smoke alarms for fires originating elsewhere in the residence. This was combined with statistics on smoke alarm coverage, residential fires, and fatalities to quantify the unsuccessful evacuation outcomes. These results were compared with the number of fire fatalities where a closed bedroom door could offer a benefit. Overall, it was found that the number of unsuccessful evacuation outcomes from a closed bedroom door were relatively small and that the potential benefit of closing a bedroom door was far greater. The analysis concludes that on a purely technical basis, closing the bedroom door at night will save lives and provides a net benefit to the public. [ABSTRACT FROM AUTHOR]

Research characteristics and define toxic substances that remain in emergency clothing after fires in abandoned and demolition buildings. As a basic component of the integrated rescue system, members of the Fire and Rescue Service may be primarily or secondarily exposed to the effects of dangerous substances that penetrate the body as part of intervention activities. Personal protective equipment (PPE) used by firefighters can be characterized as a potential source of hazardous exposure to toxic contaminants commonly found and released during fires. The research task was to detect these contaminants in individual samples based on gas chromatography (GC) and subsequently to determine the decontamination methods of firefighters and PPE after an intervention. Based on a real intervention in an abandoned and demolished building where there was a fire, firefighters from individual fire stations intervened, where, as stated in the research, they intervened in the mentioned protective equipment. The amount of dangerous substances was determined based on gas chromatography in the Control and Chemical Laboratory of the Ministry of the Interior in the village of Jasov. The stated procedure was used to determine the amount of residual hazardous substances on emergency clothing and the procedures for possible elimination of the hazard. [ABSTRACT FROM AUTHOR]

The article discusses the importance of technological innovations for occupational safety and latest technologies for disaster risk management during emergency building evacuation plans in Companies. The article also focuses on the latest innovations for emergency lighting for buildings seeking environmental certifications by the company, Zemper, ensuring public safety guildelines and organizational effectiveness in financial growth of the company.

A short-term rapid subsidence event occurred in the Bi Guiyuan community in Balitai Town, Tianjin City, leading to the tilting of high-rise buildings and the emergency evacuation of over 3000 residents. In response to this incident, InSAR (Interferometric Synthetic Aperture Radar) technology was swiftly employed to monitor the subsidence in the area before and after the event. Our observations indicate that the region had maintained stability for 8 months prior to the incident. However, over the course of the 15-day event, the ground experienced more than 10mm of subsidence. By integrating the findings from an InSAR analysis with geological studies, we speculate that the rapid subsidence in the region is related to the extraction of geothermal resources. It is suspected that during drilling operations, the wellbore mistakenly penetrated a massive underground karst cavity. Consequently, this resulted in a sudden rapid leakage of drilling fluid, creating a pressure differential that caused the overlying soil layers to collapse and rapidly sink into the cavity. As a result, short-term rapid subsidence on the ground surface and tilting of high-rise buildings occurred. [ABSTRACT FROM AUTHOR]

Indoor fire is a sudden and frequent disaster that severely threatens the safety of indoor people worldwide. Indoor fire emergency evacuation is crucial to reducing losses involving various objects and complex relations. However, traditional studies only rely on numerical simulation, which cannot provide adequate support for decision-making in indoor fire scenarios. The knowledge graph is a knowledge base that can fully utilize massive heterogeneous data to form a sound knowledge system; however, it has not been effectively applied in the fire emergency domain. This study is a preliminary attempt to construct a knowledge graph for indoor fire emergency evacuation. We constructed the indoor fire domain ontology and proposed a four-tuple knowledge representation model. A knowledge graph was constructed with 1852 nodes and 2364 relations from 25 indoor fire events. The proposed method was tested for the case study of Henan Pingdingshan '5.25' Fire Accident in China. Results show that the proposed knowledge representation model and the corresponding knowledge graph can represent complicated indoor fire events and support indoor fire emergency evacuation. [ABSTRACT FROM AUTHOR]

The collection of relevant information about the vulnerability of infrastructure damaged by landslides is not an easy task due to the existence of several compounding factors and uncertainties. This makes it difficult to quantitatively estimate their vulnerability to slow-moving landslides. This paper presents a new vulnerability assessment model for masonry buildings on slow-moving landslides based on physical models and field observations. A masonry building model is made of brick and concrete at a scale of 1:10 to physically simulate the damage in structures caused by ground tension cracks commonly developed on slow-moving landslides. The tension crack opening process is simulated through a load-controlled table with an aperture on which the building model is constructed. The strain on the wall and its foundation were measured, and the damage of the model (crack formation and evolution for each loading step) was collected, described, and analyzed. These data were used to develop failure criteria for masonry buildings in rural areas in China in terms of a quantitative vulnerability curve. The quantitative model of vulnerability for masonry structures was established based on fuzzy mathematics and the Weibull function applied on the test data and observations. The vulnerability curve is verified with field cases of masonry buildings damaged by ground tension cracks associated with slow-moving landslides in the Three Gorges Reservoir area. The results support further testing and use of vulnerability curve proposed. [ABSTRACT FROM AUTHOR]

In modern buildings, false ceilings are widely used for building services systems and aesthetic purposes, but they also pose challenges in terms of fire safety. A fire accident typically results from the failure of multiple safety measures or components. In many fire accidents, fire and smoke reached the false ceiling and kept spreading in the interstitial space without any detection. This study first generates a numerical database of false ceiling fire scenarios by varying the room dimensions, false-ceiling leakage area, fire size and locations. Then, a smart model based on machine learning to predict the fire smoke motion below and above the false ceiling is developed. The trained model is capable to predict the activation time of fire detectors and sprinklers for any given false ceiling design and fire scenario. This methodology enables a designer to generate multiple fire scenarios and determine the available safe egress time (ASET) for performance-based fire engineering designs especially in terms of fire detection time. In case of a real fire, with the data feed from the fire sensor network, the trained machine learning model can further predict the critical building fire events with the false ceiling, such as multi-compartment fires, smoke in the evacuation path, and structural failures. This work proposes a smart framework for improving the building fire safety design of false ceilings and the sensor-driven fire forecast to support firefighting.It enhances the emergency response processes by enabling dynamic risk assessment through prediction of critical events. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

During an evacuation from a building, the use of particular exits may vary significantly resulting in some becoming crowded while others are rarely used, which may cause inefficient egress. In this study, a new method of quantifying this varying exit usage and subsequently categorizing them into five different performance groups is proposed. This method is expected to allow us to compare the performance of exits in the same building as well as exits between separate buildings. To quantify the exit usage, the actual numbers of occupants using specific exits for a certain period are needed as well as the design occupant load and design number of occupants using the specific exits. The former values are obtained by actually counting occupants and the latter values are determined by exit design criteria, i.e., calculations found in building and life safety codes. Seven exits are selected from two buildings and their performance is compared quantitatively as a proof of concept. We hope these equations can be used in future research for the quantitative and qualitative study of exit usage. [ABSTRACT FROM AUTHOR]

Rapid perception of the location of the fire point is crucial to building fire emergency response in the process of building fire emergency response, which can help firefighters direct fire-fighting operations, effectively control fire sources, and provide strong evidence for the analysis and investigation of fire causes. This paper uses acoustic CT temperature measurement technology to determine the fire source location of a building fire and verifies its validity and applicability as follows: we construct various fire point numerical models based on the fire dynamics simulator (FDS) and obtain temperature data at different times; neural network means were used to obtain the time-of-flight (TOF) of an acoustic wave traveling; the large ill-conditioned matrix equation of acoustic flight under different meshing schemes was constructed and solved based on the simultaneous algebraic reconstruction technique (SART) and least squares QR-decomposition (LSQR), and then reconstruction temperature data under each scheme were obtained. Through the error analysis, the reconstruction effect of each reconstruction scheme is evaluated, and then the applicability of the location coordinate determination of the fire point is analyzed. The results show that the determination of the fire location under the conditions of various fire points in the building space can be realized by acoustic CT temperature measurement technology. [ABSTRACT FROM AUTHOR]

To accurately simulate realistic pedestrian evacuation from a fire, a cellular automaton model of the dynamic changes in pedestrian movement parameters is developed in conjunction with fire dynamics software. The fire dynamics software is used to simulate the spread of smoke within the scene to obtain visibility and CO concentration data within the scene. We imported the smoke data into the cellular automata and adjusted the pedestrian movement speed over time, resulting in simulation data that closely align with reality. The results show that for the single-room scenario, as pedestrian density increased from 0.1 to 0.5 persons per square meter ( p / m 2 ), the influence of the percentage of pedestrians familiar with their location on evacuation efficiency decreased from 44.93% to 24.52%. Conversely, in the multi-room scenario, it increased from 23.68% to 38.79%. The proportion of pedestrians less affected by smoke decreases and stabilizes as the CO yield increases. In the single-room scenario, when the CO yield is below 10%, the crowd with a low percentage of pedestrians familiar with the site is more affected by smoke than those with a high percentage. In the multi-room scenario, the victimization rate of the crowd follows an increasing-then-decreasing curve, ultimately stabilizing with changes in CO yield. [ABSTRACT FROM AUTHOR]

This study proposes a modified cellular automaton to simulate passenger ship fire evacuation. A fire dynamics simulator (FDS) is used to simulate the firing process for the passenger ship. The generated carbon monoxide (CO) concentration, temperature, and visibility are converted into equivalent lengths and input to the equivalent field of the modified cellular automaton. The fire field is applied to keep the evacuees away from the fire. And game theory is adopted to solve the conflict in the choice of route for evacuees. With or without fire on the passenger ship, three different evacuees' densities are used to study the influence of different proportions of evacuees who are familiar with exits during the evacuation time. The positions of exits are also studied. The results show that when the fire release rate increases from 3000 to 8000 kW s−2 for the same evacuation scenario, the earliest time that evacuees are in danger is 50% earlier. The impact of fire on evacuees is greater than that of evacuees' density. In the case of two close exits or exits close to the bulkheads, the congestion near exits is obvious and has the greatest effect on the evacuation time of the high evacuees' density. [ABSTRACT FROM AUTHOR]

Cryogenic liquid nitrogen (LN 2) is proposed as an effective fire suppressant/extinguisher for challenging fires. Upon reaching a fire source, this inert cryogen vaporizes expediently and separates the fuel from the air. Additionally, it cools the burning fuel and slows down its pyrolysis/gasification reactions. A prior investigation concentrated on the survivability of single LN 2 droplets, following breakup of the jet exiting the nozzle, and the predicted the droplet size that reaches a target. This investigation addresses the application of a liquid nitrogen jet for the extinction of fires with a combination of experiments and theoretical analysis. Small scale laboratory experiments were conducted with a sprayer and larger scale experiments were conducted with a cryogenic hose and nozzle. In these experiments the reach of the liquid nitrogen jets was measured, and their fire extinction capabilities were assessed. Numerical simulations were performed with the ADREA-HF CFD code using the mixture approach and explicit modelling of LN 2 evaporation using the Lee model. Numerical results on the reach of a liquid nitrogen jet qualitatively matched the experimental observations for release of a liquid nitrogen jet in open atmosphere. The Lee model coefficient was found to depend strongly on the nozzle diameter. An integral model was also constructed to explore the effects of relevant parameters, such as the LN 2 storage tank pressure, the initial jet vapor quality, the jet velocity at the nozzle exit and the effects of the ambient air entrainment. Based on experiments and theoretical analysis, it became evident that for effective extinction of a fire with liquid nitrogen a commercial nozzle should have a large diameter and should be brought close to the burning target, i.e., within a few meters. As this action can pose potential safety risks to firefighters, the advancement of the nozzle towards the fire should be operated remotely. [ABSTRACT FROM AUTHOR]

This study focuses on vehicle and pedestrian traffic management in freeway tunnels during emergencies such as fire propagation caused by traffic accidents. Such accidents can result in traffic breakdowns in a short time and a limited space, leading to severe health and safety issues. This study establishes a parsimonious bimodal tunnel evacuation management strategy that can provide real-time evacuation instructions by combining real-world historical traffic data and a cell transmission model (CTM). To exploit the evacuation capability of road tunnels with both vehicle cross and passenger passages, an equivalent cellular traffic network of a road tunnel and its escape facilities is first developed for bimodal evacuation. Simultaneously considering efficiency and social fairness in an emergency evacuation, a risk evaluation function is initially established and embedded in a system optimal objective function. The rationale of the proposed compact system models and the mechanism of effective traffic management measure generation is validated based on a real freeway tunnel emergency happened in Melba and Mullum-Mullum tunnels in Melbourne, Australia. The results suggest that the proposed CTM-based model has twinned the bimodal traffic characteristics and the flexibility to balance the evacuation efficiency and social fairness consideration in road tunnels under emergency conditions. [ABSTRACT FROM AUTHOR]

Building evacuation safety has been one of the focal points of researchers, and there is a wealth of research findings for certain places (e.g., buildings with a high population density) or for particular research subjects (e.g., the physically challenged ethnic group). However, current publications are relatively rare in analyzing the features of physically impaired individuals in crowded places and their impact on the effectiveness of the whole evacuation process, including non-disabled people. Additionally, only such studies tend to concentrate on the behavioral characteristics of disabled people, which lack exploring and comparing evacuation optimization strategies and evaluation of comprehensive evacuation performance. This paper proposed a computer simulation-based method that combined horizontally phased evacuation and vertically phased evacuation, supplemented with the use of handicapped ramps and a reasonable arrangement of class locations, to achieve the optimal evacuation performance of a teaching building with special consideration of the heterogeneous population. And then, a simulated building model was constructed to test and compare the effectiveness and applicability of these approaches through 33 evacuation scenario studies. The results found that (1) component design can improve evacuation effectiveness, with the arrangement of ramps and the location of stair doors successfully reducing evacuation time by 12% and 6.6%, respectively; (2) a combination of two ramps and separate handicap access can decrease evacuation time by 18%; (3) the horizontal-phased evacuation approach drops evacuation time by 7.1%, but the vertical-phased evacuation strategy is not very efficient. When the two are successfully combined, evacuation time is further reduced to 9.2%; and (4) based on the above measures, the evacuation time can be finally shortened by 19% if the veteran teachers are concentrated in the classrooms on the lower floors. These obtained conclusions will provide significant reference and methodological support for the safe evacuation of other similar buildings with heterogeneous populations. [ABSTRACT FROM AUTHOR]

The underground space in the Starting Area in the Guangzhou International Financial City is being developed to save resources and improve land benefits. However, high-density development has increased the likelihood of fires. Therefore, PyroSim and Pathfinder were used in this study to investigate the fire smoke flow and personnel evacuation in the underground space in the Starting Area. Firstly, the 2D temperature cloud map and the temperature and visibility recorded by sensor A over time of Zone I in the Starting Area were analyzed. Then, the 3D smoke diffusion, the 3D temperature diffusion map, and the value of thermocouple and smoke obscuration recorded by sensors of Zone II were analyzed. Next, smoke flow of Zones III to V in the Starting Area under different fire source positions was simulated. Finally, the personnel evacuation model was established to simulate the personnel flow rate and density. The simulation results show that the available safe evacuation time for people is 530 s when all the firefighting facilities fail and fire breaks out in Zone I. For large public spaces, the overall spread speed of fire is fast, which requires the use of the fire control system in time to control the spread of fire. Fortunately, the space of evacuation time is relatively sufficient; it only takes 143 s to evacuate personnel safely in Zone II, which is sufficient compared to the time for the fire to completely spread. Suggestions were made for fire safety management, such as evacuating personnel to the safety exits of other adjacent areas during a fire and installing linkage fire alarm systems in large public space s. [ABSTRACT FROM AUTHOR]

In this paper, performance-based fire-protection design is used for the fire-safety design of public amenities with restrained personnel activities. In these places, tourists' activities are constrained in a limited space such as cockpit moving along the track. Since it is another typical scenario of fire-protection problem that cannot fully comply with the current mandatory codes and regulations, simulation analysis is used in order to ensure that such fire scenario could achieve performance objectives as expected. Firstly, corresponding fire-protection performance objectives, strategies and simplified evaluation criteria are brought forward in this paper. Then, through simulating the smoke flow in the fire using the computational fluid dynamics software FDS, the effectiveness of the smoke control strategy is verified. Meanwhile, the escaping environments of these fire scenes are analyzed. Further, the personnel evacuation simulation software (Pathfinder) is resorted to simulate the personnel emergency evacuation. The efficiency and the total time that consumed are obtained. Finally, by analyzing the similarities and differences of evacuation under different fire scenes, the fire and smoke spread in the riding area can be effectively controlled, and a safe evacuation environment can be provided for the evacuation of tourists. [ABSTRACT FROM AUTHOR]