• Fire Science and Engineering
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• v.15 no.1
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• pp.34-40
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• 2001

Fire extinguishing efficiency of mixed gaseous agents were investigated by the cup-burner test and predicting by the model of flame extinguishing concentration. The binary mixed agents that tested were carbon dioxide/HFC-23, carbon dioxide/HCFC-22, carbon dioxide/HFC-227ea, carbon dioxide/HFC-125, carbon dioxide/FIC-13I1, Hexafluoropropylene/HFC-23 and ternary mixed agents were carbon dioxide/HFC-23/HFC-l34a, carbon dioxide/HFC-23/HFC-227ea, carbon dioxide/HFC-23/HFC-125. A model which contains the flame extinguishing concentration and composition of pure components predicted the flame extinguishing concentration of mixture well. This model was superior when each component of the mixture exhibit physical fire extinguishing performance.

• Journal of the Korean Society of Safety
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• v.33 no.3
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• pp.46-51
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• 2018

A basic sprinkler system is a fire extinguishing system that can be easily installed in a fire-vulnerable place such as a publicly used establishments. However, the publicly used establishments are not only complicated in structure, but also have a large amount of flammable interior materials, and the users are not normally in a normal state, which is a very dangerous fire-fighting object. Therefore, due to the low fire extinguishing performance of the basic sprinkler system installed in the publicly used establishments, the fire suppression control can not be performed quickly in case of fire, which may increase the life and property damage. In this study, the cases of quantitative changes of extinguishing water used in basic sprinkler system and the cases of addition of additives such as wetting agents, reinforced agents to improve extinguishing performance were compared. Experimental results showed that the extinguishing performance was improved as the quantity of extinguishing water increase and the reinforced agents showed similar performance to that of 60% increase in the amount of extinguishing water. The cooling time to $200^{\circ}C$ and oxygen concentration were improved up to 14.3% and 34.5%, respectively. In the case of using the wetting agent, the cooling time to $200^{\circ}C$ and oxygen concentration did not show any significant improvement, but showed the effect of preventing deep seated fire. In order to prevent loss of life and property, it is necessary to improve the performance of the basic sprinkler system by increasing amount of extinguishing water or using additives like reinforced agents.

• Journal of the Korean Society of Safety
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• v.23 no.6
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• pp.95-99
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• 2008

Halon was known as a cause of the ozone layer destruction. In 1987, it was designated as one of the ozone-layer-destroying materials in the Montreal Protocol. Therefore substitutes of Halon agent has been developed including inert gas extinguish system, which is one of the most widely used fire extinguishing system. This study intended to increase the efficiency of inert gas extinguishing agent by using inert gas additives. As IG-541 shows high extinguishing power, the experiment was performed to measure the effects of gaseous additives to it. Cup-burner fire extinguishing apparatus was used with n-Heptane fuel. Among many of pure inert gaseous agents, Helium showed the most excellent extinguishing power. When Helium was added to IG-541, fire extinguishing power was increased and the concentration of oxygen in chimney also risen. By adding Helium to IG-541, the effectiveness of inert gas fire extinguishing system is able to be increased.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2009.04a
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• pp.165-171
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• 2009

A compound agent that mixes inert gas agents and halocarbon agents and a complex fire suppression system using the compound agent have been developed. The ultimate goal of this study is to develop the extinguishing agent which doesn't destroy the ozone layer and has low GWP and to develop the fire suppression system. As a result of the test and research for inert gas agents and halocarbon agents, nitrogen and FK-5-1-12 were selected finally and have been tested and studies for three years. Thus, the optimal extinguishing agent and fire suppression system have been accomplished. The performance of the agent and system was tested according to KFI performance test technical standards for gas fire extinguishing system and the fitness of the agent and system for a fire was certified by Korea Fire Industry Technology Institute (KFI).

• Journal of the Society of Disaster Information
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• v.19 no.3
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• pp.644-655
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• 2023

Purpose: Metal fires occur in metal handling, processing, waste storage plants, etc. It is difficult for firefighters to extinguish metal fires, and it takes a long time, so caution is needed in fire suppression. Method: In this study, current statistics and problems of metal fires were introduced, and then the effectiveness was verified by experiments with using fire extinguishing agents used in Korea. Comparative suppression experiments of 5 different fire extinguishing agents for burning powders of 99.9% magnesium over 150 ㎛ were performed following the metal powder type test method of Class D fire in ISO 7165. Result: 5 fire extinguishing agents are the power types of dry sands and expanded vermiculites most commonly used in Korea, the certified class D fire extinguisher used abroad, and ochers requiring verification, and the liquid silica gel. Conclusion: The results of experiments showed expanded vermiculites were the best metal fire extinguishing agent considering effectiveness, convenience of use, and economical feasibility.

• Fire Science and Engineering
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• v.32 no.5
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• pp.22-33
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• 2018

The amount of halogen clean fire extinguishing agents has been increased by the excellent features of extinguishing, adaptability and no residue. On the other hand in situations without a hazard assessment and safety standard of agents, chemical accidents by the agents occurs frequently. This study was performed to propose the halogen clean agents' regulatory exposure limit and safety standard including the quantitative ventilation system with gas leak monitoring, hazard recognition and optimal personal protection selection through a literature review and experimental research.

• Fire Science and Engineering
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• v.16 no.3
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• pp.77-83
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• 2002

We measured flame extinguishing concentration and flue gas composition in the n-heptane fuel cup-burner system using inert gas agents such as nitrogen, argon, carbon dioxide and their mixtures. The flame extinguishing concentration of binary gaseous mixture was well predicted by model which contains the flame extinguishing concentration and composition of pure components. The higher average specific gravity of the mixed inert gas agents, the more excellent flame extinguishing performance. And the structure of enclosed space also affects the fire extinguishing. The composition of carbon dioxide in the flue gas was decreased with increasing extinguishing agent used. Nitrogen monoxide production is not related with increasing nitrogen, but increased at rapid mass flow rate of air in the cup-burner.

• Fire Science and Engineering
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• v.28 no.4
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• pp.1-7
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• 2014

Several complex devices and equipments are installed in the car's engine room, including various kind of oils or other flammable materials. So re-ignition is very likely to take place in it. In addition, it is restrictive for the driver or the occupant to open the bonnet and to spray the fire extinguisher in the engine room due to the high possibility of explosion. Therefore, a fire extinguishing system, which can detect a fire and inject the fire extinguishing agent to extinguish it, and fire extinguishing agents including HFC-227ea, which can stand the high temperature within the engine room and hold the viscosity sufficient to keep it in the kind of foam, were developed and tested. And the suffocation effect and the cooling effect come from the fire extinguishing principle of the foam fire extinguishing agent and the inhibiter catalyst effect come from the one of HFC-227ea was led simultaneously, and fire extinguishing agents without the secondary damage caused by residuals after the fire extinguishment like a case of the powder fire extinguishing agent, were developed. And experiments using a vehicle collision after the discharge is complete, foreign material can be removed without extinguishing the advantage that experimental results obtained.

• Journal of the Korean Society of Safety
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• v.27 no.6
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• pp.59-63
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• 2012

The use of dry chemical powder has been increased as it can be stored for a long period and sustain in stable condition compared to gas or liquid phase extinguishing agents. A new type of dry chemical powder using Zeolite was produced in the research. Chemical powder was adsorbed into Zeolite 13X, a porous material appearing negative catalytic effect, to create extinguishing powder obtaining core shell structure and measured physical properties and run a small scale fire extinguishment. SEM, XRD, TA analysis was also executed, and extinguishing characteristics were measured by fire extinguishing experiment on oil pool fire. The experiment showed that the average particle size of Zeolite 13X was equivalent, indicating about $3{\pm}1{\mu}m$ and thermal analysis result illustrated that Zeolite 13X showed exothermic reaction peaks at $900^{\circ}C$ due to solid-state transformation. Extinguishing characteristics on oil fire of $NaHCO_3$/Zeolite 13X and $NH_4H_2PO_4$/Zeolite were improved, influenced by adsorbed extinguishing powders on Zeolite 13X and Zeolite 13X that contains high phase transition temperature.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1539-1546
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• 2011

Halon which is one of the typical fire extinguishing agents for special purposes was banned not only to use but to manufacture because it destroys the earth's ozone layer. There have been many efforts to find or create Halon alternatives and Novec1230 which is one of the eco-friendly fire extinguishing agents is nominated. In this paper 6 kinds of valve structures were suggested to apply Novec1230 to fire extinguishing agents for railroad vehicles as Novec1230 needs different valve specifications from Halon and spray shapes and action time were compared and measured. As the results, the extinguishing times of A type and F type valves are 20% faster than the other 4 types, and 178% faster than MIL-DTL-62547(USA). Therefore, they can be suggested to the eco-friendly extinguishing agents and Novec1230.