Evaluating Fire Risk of Long-term Care Hospitals for the Elderly

Long-term care hospitals for the elderly have a high risk of fire. To reduce this risk, the installation of a horizontal refuge area has been stipulated since 2015. However, most hospitals are still at risk due to the lack of retroactive regulations. Therefore, in this study, the efficiency of the horizontal refuge area was analyzed through evacuation safety evaluation using fire and evacuation simulations. As a result of evacuation safety evaluation for the two hospitals, the reduction ratio of evacuation time was 70% (day time) and 77% (night time). In addition, evacuation safety can be secured through the installation of a horizontal refuge area. The results of this study are expected to be used as a basis for preparing retroactive regulations for horizontal refuge areas in long-term care hospitals for the elderly in the future.

A Study on the Method to Secure Evacuation Safety of Long-term Care Hospitals for the Elderly through Actual Condition Surveys

In long-term care hospitals, there are many patients with reduced mobility and the fire compartment is difficult, so there is a high possibility of large-scale casualties in the event of a fire. Various studies have been conducted to reduce these risks, but studies on problems related to evacuation safety and improvement measures are lacking. Therefore, this study intends to examine the problems related to evacuation safety through a fact-finding survey targeting two hospitals and to suggest improvement measures. As a result, problems related to 1) maintenance of fire doors, 2) establishment of a horizontal evacuation plan, 3) evacuation mechanism, and 4) recognition and implementation of worker evacuation plans were derived, and improvement measures for each problem were suggested.

Determination of Appropriate Operation of Firefighting Facility using Fire and Evacuation Simulations

Recently, a performance-based design of a fire protection facility has been proposed that significantly contributes to the construction of safe and reliable buildings. Improving the performance of the fire protection facility will enable protection of the public along with the infrastructure. Designs focusing on the fire protection performance generally add or modify architectural aspects through fire and evacuation simulations. However, a secure evacuation system aided with CCTVs has rarely been considered as an active system. Particularly for apartments, it is very difficult to assure evacuation safety without using an active system in fire and evacuation simulations with the front door of the burning room open. Safety can be achieved by combining a passive system with an active system, on the basis that the building premises has the foundation of a passive system. The regulation on the evacuation delay time in the nation was brought in effect through the SFPE paper but was deleted since the data reliability was insufficient. Therefore, the aim of the present study is to analyze the operation of a fire protection facility required to ensure safety by planning multiple simulations of a fire and evacuation system. An apartment has been considered as an example to design the foundation for a standard evacuation safety system. An active system is applied to execute fire and evacuation simulations, with focus on the fire protection performance.

Comparison of the Spreading Characters of Fire Products in the Typical Metro Stations of Washington, D.C., and Guangzhou

Fire is one of the most common disasters that threaten the safety of the crowd in metro stations. Due to the variations in the design of metro stations, the hazard posed by the spreading products of the fire can pose different risks. The typical structures of metro stations in Guangzhou and Washington, D.C., are very different from each other. In Washington, D.C., the “high-dome” structure is predominant in the construction of metro stations, while in Guangzhou, most metro stations have the “flat ceiling” structure. In this article, a numerical modeling for fire dynamic simulation is used to predict and compare the spreading characters of fire products (the smoke height change, the temperature distribution and the visibility change) when fires with 2.5 MW heat release rate occur in the platform center and at the platform end in the two kinds of metro stations. The results show that, in the same fire scenario, the lowest smoke heights monitored in the Guangzhou model is 0.6 m (fire at the platform end) and 0.8 m (fire in the platform center) above the safe smoke height in 360 s after a fire breaks out, while it is 6.15 m (fire in the platform center) and 6.2 m (fire at the platform end) above the smoke height in the Washington model. The temperature increment in the Guangzhou model is 23 °C (fire in the platform center) to 29 °C (fire at the platform end) in 360 s after the fire breaks out, while the temperature increment in the same period in the Washington model is 8.5 °C (fire at the platform end) to 9 °C (fire in the platform center). The visibility of most areas on the platform of the Guangzhou model is about 1 m no matter the fire is in the platform center or at the platform end at 360 s after the fire begins, while in the Washington model, the visibility of most areas is 1.5–13.5 mm (fire at the platform end) to 4–14 m (fire in the platform center) at the same moment. Based on the results, the environment is worse when the fire happens at the end of the platform than that when the fire happens in the platform center of the Guangzhou model. While the fire location has fewer impacts on the smoke height, temperature, and visibility in the Washington model, metro stations with a high-dome structure can be beneficial to fire evacuation safety; however, the construction cost can be high. Metro stations with flat ceiling are widely used in more cities for it has lower construction cost; to compensate for its weaker abilities under fire conditions, it is suggested that smoke exhaust systems should be carefully and fully considered.

A Study on the Improvement Plan of Performance-based Design of Officetels of Residential Structure

This study aims to identify the effect of the occupant density, application of the evacuation delay time, and the degree of opening of the fire doors in the household, parameters that are used in the performance-based design of the officetels of a residential structure, on the evaluation of evacuation safety and to suggest realistic alternatives. To this end, a preliminary survey was conducted on the number and ratio of residential officetels among the performance-based design targets in Gwangju Metropolitan City, which were implemented up to December 2020. Following this, two representative examples were selected, and for each type, an occupant density of 9.3 m2/person and 18.6 m2/person and an evacuation delay time of W1 and W2 were applied. In addition, for the degree of opening of the fire doors, full opening, 1/4 opening, and leakage gap were applied. With these conditions, the evaluation of evacuation safety was performed for 32 cases. Results of the evaluation showed that evacuation safety was secured in all cases for an occupant density of 18.6 m2/person, an evacuation delay time of W2, and the application of a leakage gap to the opening of the fire door. Therefore, using the above mentioned three parameters for the performance-based design of officetels of residential structures, we have proposed a more realistic design method in this study.

A Study on the Analysis of Vertical Walking Speed Considering the Confluence of Occupants in the Stairwell of a High-rise Building

In a fire incident case in a modern high-rise complex building, most occupants use the stairs to evacuate; hence, it is critical to secure the safety of vertical escape routes, such as the stairs. However, in Korea, the size of the stairwell is stipulated as a universal standard, and there are insufficient regulations and studies on the behavioral characteristics of occupants that may occur during the vertical evacuation of buildings. Therefore, in the evacuation experiment conducted at the W University in Japan, the relationship between the density and velocity of the occupants and the flow coefficient were analyzed during merging in the stairwell to derive a regression equation. When the stair width acted as a variable, the behavioral characteristics of the occupants and the evacuation time inside the stairwell were analyzed to obtain the basic data for improving the evacuation safety in the stairwell.

High-Rise Building Evacuation Simulation Based on Physical Stamina of Evacuees

Currently, high-rise buildings are being continuously constructed, and thus, it is necessary to predict evacuation safety in advance in case of emergency situations in high-rise buildings. However, current studies focus only on the movement of individuals in evacuation situations for predicting the final evacuation time. Therefore, in this study, a simulation of realistic evacuation in high-rise buildings was performed based on characteristics such as the physical stamina of evacuees. The evacuation simulation was performed on the world's tallest high-rise building, Burj Khalifa, and comparative verification was performed with and without consideration of the physical stamina of evacuees. The results of the simulation indicated that the total evacuation time significantly increases when physical stamina is considered. Hence, realistic evacuation in high-rise buildings is possible when the stamina of evacuees is considered.

Modelling Route Choice in Crowd Evacuation on Passenger Ships

This paper proposes an agent-based simulation model with route choice process to predict the crowd behaviours and evaluate the evacuation safety on passenger ships. The model focuses on the behaviours of two common types of passengers that are not typically accounted for during most evacuation analyses, namely, passengers who are not familiar with the ship layout and passengers who have family members or friends with them. In the proposed model, a marker concept is introduced to represent critical routing points of the layout and passenger agents make a route choice based on their surroundings and characteristics instead of just following the shortest routes. The simulation model is tested by two small but targeted scenarios and one comprehensive scenario on a ship deck. For ship designers, a more realistic evacuation time is provided to better assess the evacuation performance of a ship, and a heat map of crowd density is presented to identify possible bottleneck areas.