• Fire Science and Engineering
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• v.23 no.6
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• pp.10-15
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• 2009

Flame height calculation in a forest fire is a crucial part of predicting horizontal or vertical flame spread flared by radiation heat transfer. Flame height, which is one of the flame characteristics, can be estimated by the average height of luminous flame. This research relied on flame height observation test on P. densiflora surface fuel bed, which are surface combustibles in a forest, and calorimeter to measure Heat Release Rate, thus produced $H_f=0.027(\dot{Q'})^{2/3}$, flame height calculation equation for surface fuel. The research did not take into consideration such conditions as external velocity, slope and other variables that could affect flame height. According to comparison among experiment results, calculation results of the above formula and those of existing Heskestad formula (1998), it was found that standard error in fallen pine needles between experimental results and calculation results of the above formula amounts to 0.08, whereas standard error in same plant between experimental results and calculation results of existing Heskestad formula amounts to 0.23.

• Fire Science and Engineering
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• v.31 no.4
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• pp.26-34
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• 2017

The purpose of this study is to identify and improve the performance of the adjacent room ventilation system in living room ventilation facilities, and compare and analyze the smoke control regulations of the NFPA code and the national fire safety standard (NFSC). The analysis method was fire dynamics simulation (FDS) and was used to analyze the, variations of the air supply amount, width of the boundary, change in indoor combustion and wind velocity of the incoming air. It was found to be advantageous to secure the clean layer when the amount of air supplied is less than the amount of discharged air in the fire room. However, in the supply room, it is more effective to secure the clean layer when the amount of supplied air is larger than the amount of discharged air, as a longer boundary width gives rise to better performance. In addition, it is necessary to consider the amount of air supplied and discharged as a function of the kind of flammable material. Moreover, decreasing the air inlet wind speed and amount of incoming air is advantageous for securing the clean layer of the fire room.

• Journal of the Society of Disaster Information
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• v.15 no.1
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• pp.98-108
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• 2019

Purpose: The purpose of this study is to test the sprinkler performance to protect the wall and ceiling joints of the sandwich panel warehouse in case of fire. Method: Based on the field surveys, test was setup and combustibles were prepared. The sprinkler discharge tests were performed at the corner of the wall and right under the sprinkler head. Results: It has been found that operation of the K-80 closed sprinkler head prevents the ignition of the sandwich panel and therefore no damage to the joints of sandwich panels. To prevent skipping phenomenon, it is necessary to install the sprinkler head from the corner of the wall and to keep a minimum distance of 2.4m and a maximum distance of 3m. Conclution: A Standard Operation Procedure should be prepared to suppress and rescue of fire brigade for a sandwich panel warehouse protected by perimeter sprinklers preventing a ignition of core materials and control fire.

• Journal of the Korea Institute of Building Construction
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• v.21 no.1
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• pp.79-86
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• 2021

On the construction site, there exists frequently a high likelihood that a fire accident can lead to a large-scale disaster. In the previous studies, the diverse outcomes have been focused on the improvement of relative statutes and tried to realize the suppression and confrontation of the fire accidents. In this study, the limitations on the site were identified through prior research reviews, and the fire risk assessment checklist was proposed through the analysis of the massive accident cases. The checklist was divided into the prevention and minimization steps and developed into 16 categories of total risk factors. According to the results from the cases applied in this study, if the installation status is checked, such as removing combustibles, and broadcasting facilities for evacuation are installed, it is expected that the casualties will be minimized or zeroed. By developing a fire risk assessment checklist, this study provides the implications of the theoretical and realistic fire accident prevention, and supports the ways to minimize the damage resulted from the fire accidents on construction sites. In the further, deriving universe and common items about repeated occurrences of a work type will be needed as a subsequent research.

• Journal of the Korean Institute of Gas
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• v.27 no.3
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• pp.84-90
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• 2023

Oxygen, which is always present in the atmosphere among the three elements of combustion, can cause fires and explosions with only a very small amount of combustibles under high-pressure oxygen conditions. The burning rate is also significant, and can rise to temperatures that can have a direct impact, such as melting process equipment and piping in an instant. Therefore, accidents that occur under high pressure oxygen often cause more damage than other accidents. Recently, while operating a valve installed in an oxygen supply pipe, rapid combustion and rupture occurred inside, resulting in human casualties due to an explosion. In the case of an old carbon steel pipe, particles generated during operation become combustible and can cause accidents. . In particular, since oxygen facilities are facilities licensed under the High Pressure Gas Safety Management Actand there are no restrictions under the Occupational Safety and Health Act, accumulating these standards is of utmost importance. Therefore, in this study, based on accident cases and overseas standards, methods for improving safety when handling hyperbaric oxygen are reviewed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.2
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• pp.9-16
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• 2024

In this paper, we aimed to convert the fire curve in volume units to a fire curve per unit area for application in the Fire Dynamic Simulator (FDS) surface heat release rate method. The fire curve was expressed dimensionlessly considering the total combustion characteristic time, and improvements were made to represent the appropriate ratios for the growth , steady, and decay phases concerning the fire intensity. Additionally, a correction function for combustion characteristic time varying with mass increase was derived. Also to control the growth time values according to the increase in mass, a function to correct the growth phase ratio was derived. Consequently, utilizing existing data, a formula was established to determine the reference mass for combustion materials and predict the fire curve based on mass increase.

• International Journal of Internet, Broadcasting and Communication
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• v.16 no.2
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• pp.227-236
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• 2024

Chinese high-rise hotels are large in size, densely populated, and have a lot of combustibles. Once a fire occurs, the fire and smoke spread rapidly, and once a fire accident occurs, it is easy to cause a large number of deaths. Fires have a greater impact on special populations such as elderly and children who move slowly. At present, research mainly focuses on the impact of high-rise building structures on evacuation consequences, but there is very little research on the safety evacuation consequences of elderly people and children in high-rise hotels. This paper focuses on the elderly and children living in high-rise hotels in China. We studied three scenarios in which the elderly and children were placed on high floors, middle floors, and low floors. For the above three scenarios, use pathfinder software for simulation, According to the simulation results, when the elderly and children are mainly concentrated in the lower floors (2nd and 3rd floors), the evacuation time is the shortest, 147 seconds. The evacuation time for the elderly and children on the middle floor (6th and 7th floors) is the longest, at 191.5 seconds. Compared to being placed on high floors, safely staying on low floors for all ages reduces evacuation time by 44.5 seconds and improves evacuation efficiency by 23.24%. The final safety evacuation plan is that in daily safety management, hotels should arrange elderly and children occupants on lower floors as much as possible to reduce the total evacuation time and improve personnel evacuation efficiency. This has great guiding significance in the safety management of high-rise hotels.

• Fire Science and Engineering
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• v.33 no.6
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• pp.87-94
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• 2019

Through a press release dated July 17, 2018, the Anti-Corruption and Civil Rights Commission recommended that the National Fire Agency develop preventive measures against fire in the "Indoor Archery Ground" and "Room Escape Café" etc., which were originally excluded from the category of "Publicly Used Establishments." This study developed the hierarchy of domains and indicators of measurement for fire risk assessment of the new business of publicly used establishments through the Delphi Method. It analyzed the goodness of fit scores (over 3.00) and secured an average score of 4.25. Using AHP analysis, the ratio of consistency for the domains of measurement of fire risk assessment was found to be 4.0%, which was lower than CR ≤ 0.1 (10%). The consistency of subsequent measurement indicators were distributed in the range of 0.1%~3.6%, and they were identified as being commonly consistent. The indicators of measurement appeared as follows in order of importance and priority: Type of Internal Passage of Establishment and Evacuation Capacity of Exit (0.316), Control of Ignition Source (0.141), Inherent Risk (0.106), Appropriateness and Adaptiveness of Fire Detection System (0.097), Control of Inflammables/Combustibles (0.084), Guides and Facilities helping Evacuation (0.075), Fire Resistant Structure and Finishing Materials (0.060), Compartmentalization and Emergency Exit (0.049), Risk of Fire Expansion (0.046), and Appropriateness and Adaptiveness of Fire Extinguishing Facilities (0.026). The findings of this study are expected to be expansively used as data for future research on the development of fire risk assessment indicators.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.154-160
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• 2020

This study analyzed the fire intensity according to the zones classification between traditional market stores using FDS software. Modeling was conducted for the Seomoon traditional market district 4 at Daegu, which places combustibles, such as textiles and clothing near the passageway. The first ignition point assumed a short circuit fire situation at the fourth store combustible. The analysis was conducted under similar conditions as the fire situation in 2016. When there was no section wall, the fire spread rapidly through radiation in all directions from the fire-origin point. After 600 seconds, the mall was burnt to the ground. When section walls were present, however, the fire could be restricted inside the compartment. The first intensity of the two analysis conditions was predicted from the total heat energy from 200 seconds (X₁) to 600 seconds (X₂), where the heat generation rate began to increase rapidly. As a result of installing section walls near the fire point, heat energy generation of approximately 11.12 MW (55.68 %) was delayed. Further analysis of smoke control, according to the section wall arrangement and re-installation facilities, will be needed to study the characteristics of fire in traditional markets comprehensively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.626-631
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• 2018

An emergency evacuation support system is used to maintain evacuation routes by pressurizing a space inside screens. In cases of fire, it is important to understand the thermal distributions in the tunnel for preventing system failure. In this study, we numerically investigated the effect of fire on an emergency evacuation support system in a large fabric store with some fire scenarios with different combustibles. The critical temperature for system failures was assumed to be $200^{\circ}C$. As a result, the highest temperature was predicted in the ceiling part due to the effect of a ceiling jet, and the fire safety of the screen was secured at distances of 20 to 30 m according to the heat release rate. To prevent the inflow of smoke into the system, it is necessary to maintain more than 5 Pa if positive pressure inside the smoke screen. The results of this study could be useful for designing an emergency evacuation support system.