• 한국안전학회지
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• 제29권6호
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• pp.49-54
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• 2014

Electrostatic eliminators are essential in various areas of manufacturing industries to protect electrostatic hazards and to reduce inferior products. For ion sources used in the charge neutralizers, there are corona discharge, soft X-ray, and ultraviolet and glow discharge. Among them, corona discharge is generally used, because the corona discharge can easily and economically produce positive and negative ions including electrons in air at atmospheric pressure. But it is necessary to equip explosion-protection electrostatic eliminators wherever hazardous atmosphere. The electrostatic eliminators and their testing method of explosion-protection type have been developed in this research. The contents and scope of the research as follows; developing the type 'Ex s IIB T4' electrostatic eliminator of explosion-protection; developing the type 'Ex s d IIB T4' electrostatic eliminator of explosion-protection; developing the explosion-protection performance testing method of electrostatic eliminator for using AC power source.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1996년도 학술발표회
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• pp.76-79
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• 1996

This paper provides an overview or an introduction covering the nature of explosions, explosion protection techniques and explosion protection systems(EPS), It is not intended to be a result for the design or research of protection including explosion suppression, venting, isolation, and an explanation to the mechanical system.

• 한국안전학회지
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• 제7권1호
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• pp.57-64
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• 1992

This study is conducted for both examination of theory for electrical explosion protection and investigation of operation condition of selected95 companies, to eseblish the safety standard of explosion protection for eletrical eqiupments that explosion is possible.

• Geomechanics and Engineering
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• 제28권3호
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• pp.209-224
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• 2022

In this study, the numerical analysis model of π-beam explosion is established to compare and analyze the failure modes of the π-beam under the action of explosive loads, thus verifying the accuracy of the numerical model. Then, based on the numerical analysis of different protection forms of π beams under explosive loads, the peak pressure of π beam under different protection conditions, the law of structural energy consumption, the damage pattern of the π beam after protection, and the protection efficiency of different protective layers was studied. The testing results indicate that the pressure peak of π beam is relatively small under the combined protection of steel plate and aluminum foam, and the peak value of pressure decays quickly along the beam longitudinal. Besides, as the longitudinal distance increases, the pressure peak attenuates most heavily on the roof's explosion-facing surface. Meanwhile, the combined protective layer has a strong energy consumption capacity, the energy consumed accounts for 90% of the three parts of the π beam (concrete, steel, and protective layer). The damaged area of π beam is relatively small under the combined protection of steel plate and aluminum foam. We also calculate the protection efficiency of π beams under different protection conditions using the maximum spalling area of concrete. The results show that the protective efficiency of the combined protective layer is 45%, demonstrating a relatively good protective ability.

• 방재기술
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• 통권19호
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• pp.29-35
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• 1995

This decument, translated and rearranged deseribes the features of dust explosion and the factors which have an important effect upon the hazard of dust explosion on the purpose of prevention the disaster caused by dust explosion. The dust explosion exist close to our common life as latently, but it seems to be overlooking in com-mon, regretably Tr need to be evoked.

• 한국화재소방학회논문지
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• 제29권6호
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• pp.20-25
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• 2015

2-Ethylhexanoic acid는 플라스틱의 충격보강제를 제조하는 물질로서 공정 중에 폭발위험성을 고찰하기 위하여 산소농도 변화에 따른 폭발범위, 폭발압력, 최대폭발압력상승속도를 실험한 결과 실험온도 $100^{\circ}C$에서, 산소농도 40~70%에서 폭발하한농도 3.2%를 구하였으며, 산소농도 21%에서 폭발하한 농도는 4.0%, 폭발상한 농도는 4.5%를 구하였다. 또한, 2-ethylhexanoic acid의 폭발압력은 산소농도 70%에서 1.4161 MPa의 최대폭발압력을 나타내었으며, 최대폭발압력상승속도를 구한 결과 산소농도 70%에서 62.692MPa/s를 구하였다.

• 한국안전학회지
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• 제28권2호
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• pp.31-36
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• 2013

For lighting of dark and hazardous workplace such as compartment of ships under construction, workers should use hand lamps of explosion-proof type. However, the heavy weight of such lamps has prevented most impatient workers from using such types of lamps extensively. In this paper, we developed a light weight hand lamp of intrinsic safety type which reduced the weight a lot while maintaining or improving the lighting and explosion-proof function. We made a prototype which consisted of lamp fixture and high frequency power supply. Testing results show that the hand lamp meets well all the explosion-proof testing requirements of the Korea Occupational Safety and Health Agency. And more, we surveyed the explosion protection technology of a light weight hand lamp, and suggested the advantage/disadvantage to apply lighting of hand lamp about economical aspect.

• 한국지열·수열에너지학회논문집
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• 제14권3호
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• pp.21-28
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• 2018

This paper presents two-step simulations to calculate the influence of blast-induced pressures on explosion-protection valves installed at the boundary between a protection facility and a tunnel entering the facility. The first step is to calculate the respective overpressure on the entrance and exit of the tunnel when an explosion occurs near the tunnel entrance and exit to approach the protection facility. Secondly, the blast pressures on the explosion-protection valves mounted to walls located near the tunnel inside approaching the protection facility are analyzed with a 0.1 ms time variation using the results obtained from the first-step calculations. The following conclusions could be derived as a results: (1) The analysis of the entrance tunnel scenario, P1, leads to the maximum overpressure of 47 kPa, approximately a half of the ambient pressure, at the inner entrance due to the effect of blast barrier. For the scenario, P2, the case not blocked by the barrier, the maximum overpressure is 628 kPa, which is relatively high, namely, 5.2 times the ambient pressure. (2) It is observed that the pressure for the entrance tunnel is effectively mitigated because the initial blast pressures are partially offset from each other according to the geometry of the entrance and a portion of the pressures is discharged to the outside.

• 한국안전학회지
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• 제13권2호
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• pp.116-121
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• 1998

Various flammable vapors as energy source and raw material have been stored, transported in the industries, and accidental leakage of these vapors occurs occasionally. Without an appropriate protection system, flammable vapors can be ignited and serious damage results from them. To reduce the risk caused by explosion, we should know the explosion limit and explosion characteristics. In this study, the maximum explosion pressure, the maximum explosion pressure rise, the effect of temperature and mixing with other vapor were measured in a cylindrical vessel. Experimental results showed that maximum explosion pressure of flammable vapor was about 3.1~$4.2 kg/cm^2$ and it was reached 3.4 times faster than that at explosion limit. The lower explosion limit was coincided well with Le Chateilier's equation, however, upper explosion limit was not.

• 한국가스학회지
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• 제10권3호
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• pp.60-64
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• 2006

카본블랙 제조공정에서 발생되는 부생가스의 폭발한계와 폭발특성을 연구하였다. 부생 가스의 75% 가량은 수분과 질소였으며 가연성 성분으로는 수소를 비롯한 메탄, 아세틸렌, 일산화탄소 등을 포함하고 있어 연료로 활용하고 있다. 부생 가스중의 가연성 가스 성분들에 의해 공정상에 폭발 및 연소의 위험이 있다. 실험결과 얻어진 폭발한계범위는 17.1%에서 70.7%였으며 르샤틀리에 법칙을 이용하여 예측한 값과는 상당한 차이가 있었다. 또한 폭발특성 실험 결과 폭발압력은 최대 $5.4kg/cm^2$이었고 평균 폭발압력 상승속도는 $39.2kg/cm^2/s$였다. 이러한 결과들은 부생 가스의 취급 및 이용에 따른 폭발이나 화재 사고시 공정과 시설 등에 치명적인 손상을 입힐 수 있으므로 가스폭발 방지 및 방호조치가 필요하다.