• Proceedings of the Safety Management and Science Conference
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• 2012.11a
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• pp.215-223
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• 2012

Or maybe moving dangerous goods tanks of motorists excluded from the scope of the supervision of the fire department and fire prevention education as a blind spot on the part of a large party evidence of markers of contamination loading of dangerous goods according to the type of education that can be handled only by preparing the institutional arrangements accident is blocking the moving path of Dangerous Goods moving tanks and loading dangerous goods on fire budget move the path that corresponds to the report received by securing the extinguishing agent is required to neutralize the ash and fire suppression and repression through skills training from large disasters in advance blocking devices should prepare that will.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.939-944
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• 2018

Clean fire extinguishing agents refer to chemical that can replace Halon 1211 and Halon 1310 according to the Montreal Protocol fermented to protect the Earth's ozone layer. In Korea and abroad, system standardization and performance evaluation of clean fire extinguishing agents are being carried out. This paper proposes an optimal nozzle shape by modeling and numerical analysis of various nozzle shapes based on general clean fire extinguishing system. The ejection speed of the nozzle can be improved by studying three - dimensional modeling of the nozzle for two shapes, Type A and B. Flow analysis was performed on the two types of nozzles and the gas velocity and pressure distribution were measured with different nozzle diameters. It was confirmed that the jetting speed was changed at the nozzle outlet according to the number and diameter of the nozzle holes. The flow rate increased with increasing the pressure regardless of the nozzle hole diameter. Based on the results obtained from the experiment, the K-factor value was deduced. Finally, a nozzle with a 12-hole structure with a 5-mm nozzle hole was proposed.

• Fire Science and Engineering
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• v.29 no.2
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• pp.79-83
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• 2015

The fire accident is a representative type of disaster that can largely impact on business. Therefore, precautionary measures and rapid initial response is very important when a disaster occurs. The storage of porous combustibles is inevitable in coal yard, plywood processing industry, and others that are currently operating. Initial fire fighting of fire and identifying the ignition point in such a porous combustible storage space are so difficult that if the initial response is failed, being led to deep-seated fire, surface fire is likely to result in secondary damage. In addition, deep-seated fire can cause personal injuries and property damage due to a large amount of toxic gases and reignition. Therefore damage reduction measures is required around the storage space to handle a porous flammable. Improving the penetration performance of the concentration of the surfactant is carried out as underlying study, which is about an deep-seated fire extinguishing efficiency augmentation when using wetting agents. The porous materials used in the experiments is radiata pine wood flour, which occupies more than 75% of the domestic wood market. Fire fighting water is selected as Butyl Di Glycol (BDG), which is being used for infiltration extinguishing agent, and the experiment was carried out by producing a standard solution. The experiment was carried out on the basis of the Deep-Seated Fire Test of NFPA 18. The amount of watering, porous material to the internal amount of penetration, and runoff measurement out of the porous material was conducted. According to experimental results, as the surface tension is reduced, the surfactant concentration macroscopic penetration rate decreases, but infiltration to a porous material is shown to have growth characteristics.

• Fire Science and Engineering
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• v.28 no.2
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• pp.14-19
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• 2014

A current standard exist only on the surface tension in the current domestic wetting agent technology standards, so it is difficult to the performance evaluation of the wetting agent through the standard. So this study presents the optimized performance evaluation methods by scale model experimental equipment in order to present techniques for performance evaluation of wetting agents. The purpose of this study is to investigate validity of experimental results of the self-designed scale model experiment equipment by a comparative analysis of experimental results of the NFPA 18 experiment and the experiment using the self-designed scale model experiment equipment. As a result of a comparative analysis of experimental results of the NFPA 18 experiment that evaluate only the permeation performance on the contton and the experiment using the self-designed scale model experiment equipment that evaluate the permeation performance and fire extinguishing performance on wood flour, the discrimination of the permeation performance was confirmed in both the NFPA 18 experiment and the self-designed scale model experiment equipment. And a result of self-designed experiment equipment have clear discriminatory more than NFPA 18 by internal temperature measurement using the thermocouples.

• Fire Science and Engineering
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• v.18 no.1
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• pp.7-12
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• 2004

For CFCs and Halons regulated by Montreal Protocol and their alternatives of HFC-23, HFC-125 HFC-227ea, HFC-236fa and the mixtures of inert gases of $Ar, N_2 and CO_2$, the thermodynamic properties of saturated pressure, density, enthalpy and viscosity were compared. In this study, the data from literature were expressed as a function of temperature. Thermodynamic properties of HFC compounds were similar to those of Halon-1301. Inert gas was mainly used as a mixture, but the physical properties of the inert gas does not have the favorable advantages over those of Halon-1301.

• Fire Science and Engineering
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• v.30 no.1
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• pp.111-120
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• 2016

This study is intended to provide legislative direction for fire products life expectancy. Domestic and international laws relating to fire products life expectancy have been reviewed, and the results of a Fire Safety Manager Consciousness (FSMC) survey were analyzed. The FSMC survey has been designed in order to assist with the establishment of appropriate fire safety policy. A questionnaire survey was conducted with 660 fire safety administrators from 17 municipal and provincial districts, with the intention of gaining expertise on the extension of life-span for 32 fire products. The survey also asked for candidates opinions on future policy direction. Based on the survey results and the review of policies within other nations, we have devised a set of policy issues with the intention of extending the life-span of fire-safety items. The survey result revealed that 79.3% of Fire Safety Managers (FSMs) concurred with the establishment of legislation regarding the maintenance and correct care of fire-safety products. Overall, over 30% of FSMs were in favor of regulations regarding Ddry chemical fire extinguishers (77.3%), fire detectors (44.6%), fire hoses (44.4%), gaseous agent fire extinguisher (40.6%), automatic descending life lines (36.2%), exit lights (35.9%), air respirators (35.9%), extinguishing systems for residential cooking facilities (33.9%), automatic spray-type extinguishing units (33.9%), emergency lights (31.2%), and gas leakage detectors (30.7%). Especially, among these, dry chemical fire extinguishers (60.0%), detectors (20.0%), and fire hose (18.8%) were identified as the fire products primarily in need of maintenance legislation. The general consensus is that fire products older than 10 years need to be replaced. Based on the survey results, there was general agreement that fire product life expectancy is in need of legislation. This study recommends the introduction of fire product life expectancy legislation in phases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.74-79
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• 2017

The fire extinguishing performance of hybrid nozzle systems is improved by injecting an extinguishing agent concentrically into the target site and, in this study, water mist is used as a water curtain to confine the droplets of the agent. In this study, we numerically investigated the effect of the foundation angle and injection pressure on the performance of a hybrid nozzle by evaluating the mean radius of the volume fractions of the agent and water mists. An experiment involving a water mist nozzle was carried out to validate the numerical method and then the droplet behaviors, e.g., stochastic collision, coalescence and breakup, were calculated with 2-way interaction Discrete Particle Modeling (DPM) in the steady state for the hybrid nozzle system. The mean radius of the water mists increased by about 40 %, whereas that of the agent decreased by about 21 %, when the injection pressure was increased from 30 bar to 60 bar. In addition, the mean radius of the agent increased by about 24 % as the foundation angle of the hybrid nozzle head increased from $30^{\circ}$ to $60^{\circ}$. As a result, it can be inferred that the injection angle and pressure are important factors for hybrid water mist designs.

• Journal of the Society of Disaster Information
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• v.18 no.3
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• pp.581-588
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• 2022

Purpose: This study is about offering ways of improving existing technical standards in order to propose how to deal with coal deep-seated fire and to increase effectiveness of wetting agent. Method: This study conducts infiltration experiment using eight tons of coal, three types of wetting agents and fire water. And this study analyzes domestic and international technical standards, overseas experimental cases. Result: It is found that two findings are identified; one is fire water cannot infiltrate into the coal due to high level of surface tension, and the other is three types of wetting agent can infiltrate into the coal to the depth of 5~25cm. Also, domestic wetting agent technical standards include measuring surface tension only and testing wood on extinguishing capacity test. On the other hand, this study found that deep-seated fire experiment using cotton, B-class fire test using heptane are used from abroad. Besides it is analyze that capillary rise test, sink test, contact angle measurement are conducted to increase effectiveness of wetting agent at the U.S. Bureau of Mines. Conclusion: Based on standards and cases of U.S. NFPA and Bureau of Mines, this study suggests that domestic technical standards should include adding a new test standard which measures infiltration directly.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.4
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• pp.349-355
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• 2019

A fire, be it caused intentionally or unintentionally, leads to economic loss and physical damage, and requires digestion. The number of fires is increasing yearly, and electrical fires account for more than 30% among the main causes of fires. Electric wires that catch fire typically employ silicone coatings; silicone has organic as well as inorganic properties. Silicon is a natural, nonexistent, synthetic product with numerous applications. In this study, a silicon rubber for application in wires was prepared by high-temperature vulcanization (HTV) with a Shore A hardness of 70. We report results for the flame retardancy test and the fire safety characteristics via inorganic analysis. For this, a quartz inorganic material was added to the wire specimen, and 18% powdered extinguishing agent ammonium phosphate and expanded vermiculite respectively. Thus, expanded vermiculite showed the best flame retardancy and fire safety characteristics.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.04a
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• pp.136-139
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• 2011

국가화재안전기준 107 및 107A에서 할로겐화합물 소화설비와 청정소화약제 소화설비 설계시 하나의 방호구역을 담당하는 저장용기의 소화약제의 체적합계보다 소화약제의 방출시 방출경로가 되는 배관(집합관을 포함한다)의 내용적의 비율이 설정된 값 이상인 경우 당해 방호구역에 대한 설비는 별도의 독립방식으로 하도록 요구하고 있다. 이산화탄소 소화설비의 경우에는 이산화탄소의 증기압이 충분히 높으므로 방출배관의 용적에 대한 제한사항이 포함되어 있지 않으나 저압이산화탄소 소화설비의 경우 약제의 저장온도가 낮으므로 방출시 기화되어 설계시 의도한 방출량을 만족시키지 못할 수 있다. 본 논문에서는 저압이산화탄소 소화설비에 대한 방출배관 용적 제한 필요성에 대하여 논의하였다.