• Journal of the Korean Society of Safety
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• v.27 no.4
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• pp.20-25
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• 2012

The purpose of this study is to analyze the thermal characteristics and to study fire hazard of electric leakage by iron power accumulated on circuit breaker in an iron processing factory. The thermal characteristics were analyzed while current was applied to the powder for ten minutes. Results showed that temperature of iron powder at 100 mA is $160^{\circ}C$ and at 175mA is $240^{\circ}C$. The sparks have occurred as iron powder drops between two(hot line and neutral line) wires and then iron powder explosion occurred while dropping continuously the iron powder on two lines. Those who work in the iron processing industry need to periodically remove and maintain the iron powder. The thermal characteristics in this paper can be used for electrical fire investigation and for basic data of thermal characteristic of leakage current through iron powder at iron processing factories.

• Journal of the Korean Institute of Gas
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• v.22 no.1
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• pp.9-17
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• 2018

In the consideration of the working conditions, which have several kinds of works operating at the same time, at construction sites, it is difficult to prevent industrial accidents. There are a number of works to employ flammable materials and hot works simultaneously operated without fire protection systems. It causes a huge fire and casualties. In this research to analyze an accident case, the reasonable prevention methods are suggested throughout the property tests for the organic solvents and the analysis of the behavior for vapour cloud in the underground area of the construction site.

• Safety and Health at Work
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• v.11 no.3
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• pp.322-334
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• 2020

Background: Spontaneous combustion of coal is one of the factors which causes direct or indirect gas and dust explosion, mine fire, the release of toxic gases, loss of reserve, and loss of miners' life. To avoid these incidents, the prediction of spontaneous combustion is essential. The safety of miner's in the mining field can be assured if the prediction of a coal fire is carried out at an early stage. Method: Adularya Underground Coal Mine which is fully mechanized with longwall mining method was selected as a case study area. The data collected for 2017, by sensors from ten gas monitoring stations were used for the simulation and prediction of a coal fire. In this study, the fuzzy logic model is used because of the uncertainties, nonlinearity, and imprecise variables in the data. For coal fire prediction, CO, O₂, N₂, and temperature were used as input variables whereas fire intensity was considered as the output variable.The simulation of the model is carried out using the Mamdani inference system and run by the Fuzzy Logic Toolbox in MATLAB. Results: The results showed that the fuzzy logic system is more reliable in predicting fire intensity with respect to uncertainties and nonlinearities of the data. It also indicates that the 1409 and 610/2B gas station points have a greater chance of causing spontaneous combustion and therefore require a precautional measure. Conclusion: The fuzzy logic model shows higher probability in predicting fire intensity with the simultaneous application of many variables compared with Graham's index.

• Fire Science and Engineering
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• v.20 no.3 s.63
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• pp.29-34
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• 2006

The flash and fire point are the most important combustible properties used to determine the potential for the fire and explosion hazards of flammable material. The flash point is defined as the lowest temperature at which a flammable liquid gives off sufficient vapor to form an ignitable mixture with air near its surface or within a vessel. The fire point is the temperature of the flammable liquid at which there will be flaming combustion, sustained 5 seconds in response to the pilot flame. In this study, the flash points and fire points were measured to present raw data of the flammable risk assessment for acids, using Pensky-Martens Closed Cup(C.C.) apparatus (ASTM-D93) and Tag Open-cup (O.C.) apparatus(ASTM D 1310-86). The measured fire points were compared with the estimated values based on 1.11 times stoichiometric concentration. The values calculated by the proposed equation were in good agreement with measured values.

• Journal of the Korean Institute of Gas
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• v.23 no.6
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• pp.39-60
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• 2019

Korea Gas Safety Corporation is developing consequence analysis system for combustible materials release events to enhance risk assessment technology and its efficiency. Unlike general consequence analysis programs, the final consequence area was implemented through ETA analysis based on API-581 standard, and a convenient user interface was constructed based on HTML5-based responsive web technology. In addition, a phase equilibrium module using third-order state equations (such as Peng-Robinson, SRK, and RK) and fugecity was implemented to analyze the mixture quality. Also. using the consequence analysis algorithm introduced in CCPS books and TNO Yellow Book, we developed material leak analysis module, fireball, pool fire, jet fire, flash fire, and vapor cloud explosion consequence assessment module. In addition, the conditions for calculating the safety distance were prepared with using the control values in the EIGA standard, PAC, and Bevi Reference Book.

• Fire Science and Engineering
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• v.25 no.6
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• pp.32-38
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• 2011

As the using rate of an explosive gas has been increased in the industrial site, the regional residents adjacent to the site as well as the site workers have frequently fallen into a dangerous situation. Damage caused by accident in the process using hydrogen gas is not confined only to the relevant process, but also is linked to a large scale of fire or explosion and it bring about heavy casualties. Therefore, personnel in charge should investigate the kinds and causes of the accident, forecast the scale of damage and also, shall establish and manage safety countermeasures. We, in Anti-Calamity Research Center, forecasted the scope of danger if break out a fire or/and explosion in hydrogen gas facilities of MLCC firing process. We selected piping leak accident, which is the most frequent accident case based on an actual analysis of accident data occurred. We select and apply piping leak accident which is the most frequent case based on an actual accident data as a model of damage forecasting scenario caused by accident. A jet fire breaks out if hydrogen gas leaks through pipe size of 10 mm ${\Phi}$ under pressure of 120 bar, and in case of $4kw/m^2$ of radiation level, the radiation heat can produce an effect on up to distance of maximum 12.45 meter. Herein, we are going to recommend safety security and countermeasures for improvement through forecasting of accident damages.

• Journal of the Korean Society of Safety
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• v.22 no.4
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• pp.110-116
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• 2007

There have been 3E problems of energy, economy and environment since the earth has its history. Especially, as the industrial society is highly developing, human need in daily life has also changed drastically. With the introduction of 40 hour working week system, more households enjoy picnics on weekends. More gas accidents take place on Saturdays and on Sundays than any other days of week. Consequently, this study tries to find out the influence of flame caused by the explosion of butane canister on the adjacent combustibles and people by simulating relevant quantity of TNT. In addition, the damage estimation was conducted by using API regulations. If the scale of the radiation heat is known by calculating the distance of flame influence from the explosion site, the damage from the site can be easily estimated. And the accident damage was estimated by applying the influence on the adjacent structures and people into the PROBIT model. According to the pro bit analyze, the spot which is 50cm away from the flame has 97% of the damage probability by the first-degree burn, 8% of the damage probability by the second-degree burn and 4% of the death probability by the fire.

• Journal of the Korean Institute of Gas
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• v.9 no.4 s.29
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• pp.50-56
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• 2005

Liquefied Petroleum 6aso-PG) is combustible gas which used for fuel for domestic and automobiles. A research for adjust a component of LPG to improve the fuel characteristics and control the manufacturing process of that is carrying in petrochemical industry. Some kinds of LPG blending is considered as a adjusting method to control component of LPG. LPG is mainly propane for domestic use and butane for automobile use but propylene and butylene also a kind of LPG Change of explosion characteristic and combustion gas component by mixing of propylene in propane and butane was measured and analysed in this research. Based on the result of experiment, it was found that explosion pressure and pressure rise rate was slightly increased with mixing rate of propylene and it was considered the possibility of increasing the CO concentration in combustion gas with increase the mixing rate of propylene.

• Journal of the Korean Society of Safety
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• v.25 no.3
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• pp.53-60
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• 2010

LPG(Liquefied Petroleum Gas) vehicles in metropolitan area are being applied to improve air quality and have been proven effective for the reduction of air pollutant. In addition, LPG demand is growing rapidly as an environmentally friendly energy source and its gas station is also increasing every year. Consequently, this study tries to find out the influence of flame caused by the VCE(Vapor Cloud Explosion) in filling station on the adjacent combustibles and people by simulating relevant quantity of TNT. In addition, the damage estimation was conducted by using API regulations. If the scale of the radiation heat is known by calculating the distance of flame influence from the explosion site, the damage from the site can be easily estimated. And the accident damage was estimated by applying the influence on the adjacent structures and people into the PROBIT model. According to the probit analyze, the spot which is 30m away from the flame has 100% of the damage probability by the first-degree burn, 99.2% of the damage probability by the second-degree burn and 93.4% of the death probability by the fire.

• Journal of Energy Engineering
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• v.28 no.4
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• pp.42-47
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• 2019

In this study, combustion characteristics were measured by selecting di-n-buthylamine, which is widely used as an emulsifier, insecticide, additive, rubber vulcanization accelerator, corrosion inhibitor, and raw material for dye production. The flash point of the di-n-buthylamine was measured by Setaflash, Pensky-Martens, Tag, and Cleveland testers. And the AIT of the di-n-buthylamine was measured by ASTM 659E. The explosion limits of the di-n-buthylamine was calculated using the measured flash points by Setaflash tester. The flash point of the di-n-buthylamine by using Setaflash and Pensky-Martens closed-cup testers were experimented at 38 ℃ and 43 ℃, respectively. The flash points of the di-n-buthylamine by Tag and Cleveland open cup testers were experimented at 48 ℃. The AIT of the di-n-buthylamine was experimented at 247 ℃. The LEL and UEL calculated by using lower and upper flash points of Setaflash tester were calculated at 0.69 vol% and 7.7 vol%, respectively. The measurement of the flash point measurement and the calculation method of the explosion limit prediction presented in this study can be used to study the fire and explosion characteristics of the other combustible liquids.