Metro Fire Research Articles

How do passengers’ psychological conditions and behavioral conditions change in metro fire evacuation: An online questionnaire-based experiment

How do passengers’ psychological conditions and behavioral conditions change in metro fire evacuation: An online questionnaire-based experiment

Understanding fire combustion characteristics and available safe egress time in underground metro trains: A simulation approach

Due to insufficient oxygen supply in the tunnel, incomplete combustion of the underground metro train fire easily produces toxic gases and smoke dust, causing difficulty in breathing for passengers and rescue. The experimental study of the fire combustion characteristics of metro trains in the tunnel is of great significance for designing metro fire extinguishing and fire prevention systems and providing reliable guidance for emergency evacuation in fire scenarios. A train fire model is established to study the effects of various factors on fire combustion characteristics and calculate the available safe egress time (ASET). The smoke spread characteristics under different conditions such as fire source power, fire source location, carriage layout, and train location are simulated. The simulation results show that the fire source power, location, and seat arrangement have a significant impact on the smoke spread characteristics of carriage fires and ASET.

A numerical study on smoke propagation in metro tunnel fires with different door opening scenarios

Abstract Numerical study was carried out to analyze the effect of door opening scenario on the smoke propagation in metro tunnel fires. The smoke back-layering length, critical velocity, and temperature distribution were studied under a total of 8 working conditions. Results show that the opening of emergency exit doors could result in a shorter smoke back-layering length in the train compartment. In such conditions, a smaller driving force was needed to approach the critical velocity. On the other hand, the high temperature area of the tunnel evacuation platform would change under different opening scenarios. The research result could be used as a deeper understanding of the smoke propagation of metro fire and a reference for the formulation of smoke control.

Study on Elevated Interval Evacuation of Metro Train considering the Influence of Fire, Railings, and Track Bed

Elevated metro is a typical type of urban rail transit that operates on viaducts. Due to its fast construction speed and low cost, it plays an important role in transportation systems with dense concentrations of people. Once a fire accident occurs in rush hour, it will cause high casualty and enormous injuries. In this regard, studying the characteristics of fire smoke spread and passengers’ evacuation is of profound significance. In this paper, Pyrosim and Pathfinder software was utilized to simulate metro fire and evacuation process. The variation of temperature, CO concentration, and visibility inside carriage and outside walkaway were studied to explore the characteristic of fire and smoke. Evacuation time, speed, density, and path were analyzed for six cases considering the influence of railing settings on evacuation walkaway and the use of track bed. The impact of smoke on movement speed reduction and temperature on the available door numbers were taken into consideration. Results revealed that the temperature of accident carriage rose to tenability limit after 50 s and the visibility decreased to 5 m within 150 s. CO concentration was below safety criteria due to sufficient oxygen. Temperature was the most important factor that leads to the risk of evacuation, especially inside the accident carriage. The length of evacuation walkaway could highly reduce evacuation time and density. Railings had a negative impact on evacuation while the usage of track bed had a positive effect. Besides, the impact of railings was not as significant as the usage of the track bed. Research results can provide decision‐making reference for fire protection and evacuation design to alleviate congestion and improve safety management.

Design for safety in metro station evacuation: a study of fire emergency evacuation behavior and simulation

PurposeMetro stations have become a crucial aspect of urban rail transportation, integrating facilities, equipment and pedestrians. Impractical physical layout designs and pedestrian psychology impact the effectiveness of an evacuation during a metro fire. Prior research on emergency evacuation has overlooked the complexity of metro stations and failed to adequately consider the physical heterogeneity of stations and pedestrian psychology. Therefore, this study aims to develop a comprehensive evacuation optimization strategy for metro stations by applying the concept of design for safety (DFS) to an emergency evacuation. This approach offers novel insights into the management of complex systems in metro stations during emergencies.Design/methodology/approachPhysical and social factors affecting evacuations are identified. Moreover, the social force model (SFM) is modified by combining the fire dynamics model (FDM) and considering pedestrians' impatience and panic psychology. Based on the Nanjing South Metro Station, a multiagent-based simulation (MABS) model is developed. Finally, based on DFS, optimization strategies for metro stations are suggested.FindingsThe most effective evacuation occurs when the width of the stairs is 3 meters and the transfer corridor is 14 meters. Additionally, a luggage disposal area should be set up. The exit strategy of the fewest evacuees is better than the nearest-exit strategy, and the staff in the metro station should guide pedestrians correctly.Originality/valuePrevious studies rarely consider metro stations as sociotechnical systems or apply DFS to proactively reduce evacuation risks. This study provides a new perspective on the evacuation framework of metro stations, which can guide the designers and managers of metro stations.

Evaluation of Metro Fire Emergency Response Ability Based on WRSR

In order to clarify the status of subway fire emergency response capability, a comprehensive evaluation method based on the weighted rank-sum ratio method is proposed. Firstly, the factors affecting the emergency response capability of subway fire accidents was put forward on the basis of the current relevant laws and regulations, and a subway fire emergency response capability evaluation system was also built; secondly, the Analytic Network Process (ANP) was used to calculate the weight of each indicator in the system; then, the weighted rank sum ratio method (WRSR) is used to evaluate the overall status of the subway fire accident emergency response capability, and the sub-range of each subway emergency response capability is obtained; finally, model verification was conducted with 8 typical subways in Central China. The results show that C1, C3, C16, C20 and C29 constitute important indicators of subway fire emergency response capabilities; the constructed model can comprehensively evaluate the subway fire emergency response capabilities and facilitate its safety management.

The next nine minutes: Lessons learned from the large-scale active shooter training prior to the STEM school shooting.

As the incidence of active shooters increase, local emergency response has also changed. South Metro Fire Rescue coordinated a series of hyper-realistic active shooter simulation drills involving multiple agencies. "The Next Nine Minutes" was one of the largest active shooter drills performed to date with 904 personnel that were trained in 18 mass casualty active shooter drills. Evaluation was from point of injury to and including care in the operating room (OR), and evaluation of real-time system logistics. A total of 126 patients in Cut Suits® received a total of 479 procedures such as needle decompressions, cricothyrotomies, tourniquets, wound packs, and chest tubes. Central to this exercise, law enforcement (LE) established a warm zone from the initial shooting. EMS was able to move into the facility, locate casualties, extract the first victim, move them to a casualty collection point (CCP), and transport them to safety within 12 minutes. Strengths and weaknesses were identified in prehospital and in-hospital care. These included what roles agencies play in a true event, specific timing in establishing areas such as the warm zone and CCP, transportation, and logistics at the accepting hospitals. Only after the barriers to success were identified and addressed did the timing of casualty movement drastically improve. Lessons learned from this training were ultimately used to save lives at the STEM School, Highlands Ranch, and Colorado Shooting. This in situ immersion training should be practiced as a whole system.

A new method for personnel protection failure evaluation in metro fire with multiscenario coupled three dimensional model

With a closed environment and dense population, urban metros are difficult to evacuate quickly in the case of fire, which often leads to serious consequences such as stampedes. To deal with metro fires effectively, this paper presents a three-dimensional model for assessing the failure probability of personnel protection. First, scenario elements of metro fire evolution were selected based on typical cases and traditional performance-based evaluation methods, and a scenario element database was constructed. Second, based on this approach, a three-dimensional evolution model of the metro fire scenario was established to visually express the interaction relationship of each scenario element in plane dimensions. Finally, an evaluation model of the personnel protection failure risk index was constructed by coupling the metro fire, emergency management and trapped personnel, and the failure probability of personnel protection was calculated. This model can evaluate the real-time risk of death in the process of metro fire accidents and provide an important reference for emergency decisions and plan deployment.

Physiological reaction of passengers stress metro fire using virtual reality technology

In order to prevent the occurrence of negative stress reaction of subway passengers under fire and improve the positive stress reaction ability of subway passengers, the characteristics of fire stress physiological reaction of subway passengers were analyzed by experiment and catastrophe theory. Firstly, the virtual reality technology is used to realize the subway car fire, which requires the volunteers to escape to the ground safety exit smoothly according to the prompt; secondly, the heart rate and blood pressure of the volunteers are measured during the VR experience of the subway fire; thirdly, the heart rate and blood pressure are taken as the control variables and the stress state is taken as the state variable to establish the volunteer’s cusp catastrophe model of stress physiological response. Finally, statistical analysis and qualitative fitting analysis of experiment data were carried out. The results showed that only one volunteer had negative stress response under VR subway fire stress, and other volunteers were in a state of positive stress response. The physiological stress response of subway passengers meets the potential function condition of cusp mutation.

Key technology of lightweight Web3D online planning of metro fire escape

Virtual training of metro fire evacuation definitely becomes considerably more efficient and convenient immigration of trainees from the PC desktop to mobile web browsers. However, web browsers face extreme difficulty in sustaining online visualization of large-scale building information modeling (BIM) data on metro, FDS smoking data, crowding passengers, and planning of fire evacuation path simultaneously due to the weak rendering capability and limited networking bandwidth. Herein, a novel lightweight Web3D technology roadmap is proposed to address these problems. First, the lightweight preprocessing of metro BIM data is performed by semantic and geometric retrieval of repetitive entities. Second, crowding passengers are visualized online by reusing several avatars and behavior randomly in terms of textures and scales in a lightweight manner. Third, substantial smoking data are reduced by redundancy elimination and voxel normalization and rendered online with spirit texture particle. Finally, the backbone escape paths are extracted by clustering the virtual evacuation traces that are collected by virtual reality devices, such as HTC VIVE, as initial heuristics, and a lightweight metro fire evacuation planning evacuation based on adaptive ant colony optimization is realized on mobile web browsers. Numerous tests have been conducted online, and experimental results show that the proposed method can be loaded remotely in a few seconds and visualized on mobile web browsers smoothly.

A risk-based approach for crowd evacuation performance evaluation under metro fire

This paper aims to evaluate the crowd evacuation performance in a metro fire by using the limit state equation to describe the egress process. The limit state equation is established by the available time margin in fire evacuation, which comprises the evacuee's response time, behaviour time and movement time to an exit. Here, the available time margin in a fire evacuation is determined by the duration of time the smoke takes to exceed the evacuee's respiration level, the time that the smoke is detected by fire alarm and the time that the evacuee needs to respond and move to an exit during evacuation. Further, Monte Carlo simulation approach has been employed to integrate the fatality rates and the probabilities of occurrence of different scenarios in a typical metro in Xiaobailou station of station-Tianjin Line 1. Through this case study, it is shown that the evacuee's response time, behaviour time and movement time to exits can be integrated in a stochastic process model.

Environment Protection for Human Behavior in Metro Fire

Questionnaire surveys to passengers in metro have been performed. Frequency distribution statistics was conducted about their personal information, environmental information and human behavior information in fire. On the basis on that, the author made a comparison between results of this research and ones of other researches for buildings fires in domestic, and gained a coincident result. These conclusions will provide more accurate and more effective supports for fireproofing design. At the same time, these conclusions also are good for the fire prevention and environment protection.Questionnaire surveys to passengers in metro have been performed. Frequency distribution statistics was conducted about their personal information, environmental information and human behavior information in fire. On the basis on that, the author made a comparison between results of this research and ones of other researches for buildings fires in domestic, and gained a coincident result. These conclusions will provide more accurate and more effective supports for fireproofing design. At the same time, these conclusions also are good for the fire prevention and environment protection.

Study on the Human Behavior in Metro Fire

With the rapid development of city subway, subway disaster problems aroused people's attention. Subway fire especially priority among priorities in subway disaster. This research mainly rely on the way of questionnaire survey, conducted a statistical study on metro fire evacuation behavior. The author has carried on questionnaire investigation to the passengers of some subway station in Tianjin Metro Line 1. The author sent out 116 questionnaires, received effective questionnaires 100 copies. The questionnaire content mainly includes the basic personal information, the surrounding environment and the passenger behavior in fire condition. The author analyzes the first behavior survey of different sex, different age, different education, different frequency and different subway fire experience reaction. Management departments according to the behavioral responses of passengers improve and optimize the subway facilities and fire evacuation passage.

Research on Mobile Water Spray Device Reducing the Temperature of Metro Fire

Reducing the temperature is one of the key technologies in the metro fire emergency rescue, so it is the basic work to be done. Rapid and effective cooling can reduce the casualties caused by the metro fire. Water spray can quickly absorb a lot of heat for its large surface area. Water spray can quickly cool down the temperature of the metro fire and reduce the casualties caused by high temperature. Mobile water spray device is used in emergency rescue of the metro fire in this paper. Research on the mobile water spray device can do contribution to reduce casualties caused by metro fire.

Research on Decreasing Temperature Technology of Emergency Rescue in Metro Fire

Decreasing the temperature of fire field is one of the most important technologies of metro fire emergency rescue. It is calculated that the total heat is released in metro fire and the mass of ice, liquid nitrogen and dry ice are needed when the temperature is decreased to 60°C. Ice is the best option among the three through comprehensive analysis from mass, volume, transportation, storage and so on. Research on cooling technology of emergency rescue in metro fire can do contribution to reduce metro fire casualties.

Study on availability and issues of evacuation using stopped escalators in a subway station

SUMMARYRecent years have seen an increasing number of deep subway stations, and many of the existing stations have been made progressively barrier free. This has been accompanied by the installation of more and more escalators, and often existing stairways have been converted to escalators. This has resulted in fewer egress paths in an emergency case. Considering this background, firstly, a crowd walking experiment using stopped escalators was conducted in order to get the base data, for example, on obtained walking speed, for the parameters in the evacuation simulation of several fire scenarios in a typical subway station. Secondly, a smoke movement simulation of the metro fire scenarios was conducted to demonstrate the applicability of the smoke model in a two‐layer zone model. Finally, based on the results of the evacuation and smoke simulations of the chosen subway station, we examined the availability and the issues of evacuation using stopped escalators. As a result, it was found that the evacuation potential of passengers on a platform is considerably improved if escalators are permitted in addition to stairs for emergency evacuation. Several issues to be considered for the safe operation of escalators are identified. Copyright © 2011 John Wiley & Sons, Ltd.

Study of the human evacuation simulation of metro fire safety analysis in China

Metro construction in China enjoyed and will continue to enjoy unprecedented development in the tenth 5 Year Plan period and the upcoming eleventh 5 Year Plan period. In China, cities are densely populated, and as a modernized urban rail transit means, metros have been undertaking increasingly important tasks of large passenger flow transportation, under which circumstance the injury and casualty will be enormous if an accident occurs. China's work safe laws and regulations have stipulated that safety evaluation must be carried out during planning, design, construction and operation of metros. As a part of the metro safety evaluation, occupant safe evacuation is a critical aspect to be assessed. This paper will first introduce the occupants evacuation design in the construction of metros in China based on Code for design of metro (CFDOM) (GB 50157-2003), including evacuation passage design, evacuation time and evacuation safe area as well as fire-engineering-based occupants evacuation design philosophy and calculation method. Finally, a computer simulation of the process of evacuation of occupants from deep buried metro station (DBMS) by using occupants evacuation dynamic model will be conducted on the example of DBMS of Guangzhou Metro Line 6, so as to study whether the occupants can be safely evacuated from DBMS in case of fire.

Human-Robot Interaction Design: Understanding User Needs and Requirements

Goal-Directed Task Analysis is being applied to assessing the needs and requirements for developing novel techniques and tools to permit a small number of humans to supervise large robotic teams. The paper presents a preliminary overall goal hierarchy as well as a preliminary communication goal hierarchy based upon the initial analysis. This research involves working directly with the Nashville Metro Police department's Bomb Squad and the Nashville Metro Fire Department's HAZMAT team. The focus is the assessment of actual user needs and requirements employing well-defined user centered design practices in combination with Goal-Directed Task Analysis. The resulting Goal- Decision-SA structure will be employed to develop potential human-robot interaction designs for further qualitative and qualitative evaluation. The objective is to successfully integrate robots into the Chemical, Biological, Radiological, Nuclear and Explosive device search and rescue tasks such that the robots complement and augment the current human capabilities.

Searching efficient plans for emergency rescue through simulation: the case of a metro fire

In this paper we present the way we modelled and simulated a metro system in the case of a tunnel fire, and discuss the ways this simulation may support the search for efficient rescue plans. The metro system was modelled as a complex adaptive system, comprising four interacting and co-evolving subsystems: (i) the fire and the released smoke, (ii) the group of passengers, (iii) the technological system, and (iv) the metro personnel. Based on this model, an agent-based simulation was developed. This simulation provides an appropriate dynamic representation of the designer’s problem space, enabling him (i) to apprehend the critical dependencies and invariants of the system under consideration, (ii) to identify the features that should characterise the designed emergency rescue plans, and (iii) to assess their efficiency. To demonstrate the usefulness of the adopted approach for the design of an efficient emergency rescue plan, the results of two experiments exploring alternative sequences of the metro personnel’s actions under different circumstances are presented.