• Nuclear Engineering and Technology
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• 제54권11호
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• pp.4195-4208
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• 2022

In this study, operator habitability was numerically evaluated in the event of a fire at the main control bench board (MCB) in a reference main control room (MCR). It was investigated if evacuation variables including hot gas layer temperature (HGLT), heat flux (HF), and optical density (OD) at 1.8 m from the MCR floor exceed the reference evacuation criteria provided in NUREG/CR-6850. For a fire model validation, the simulation results of the reference MCR were compared with existing experimental results on the same reference MCR. In the simulation, various input parameters were applied to the MCB panel fire scenario: MCR height, peak heat release rate (HRR) of a panel, number of panels where fire propagation occurs, fire propagation time, door open/close conditions, and mechanical ventilation operation. A specialized-average HRR (SAHRR) concept was newly devised to comprehensively investigate how the various input parameters affect the operator's habitability. Peak values of the evacuation variables normalized by evacuation criteria of NUREG/CR-6850 were well-correlated as the power function of the SAHRR for the various input parameters. In addition, the evacuation time map was newly utilized to investigate how the evacuation time for different SAHRR was affected by changing the various input parameters. In the previous studies, it was found that the OD is the most dominant variable to determine the MCR evacuation time. In this study, however, the evacuation time map showed that the HF is the most dominant factor at the condition of without-mechanical ventilation for the MCR with a partially-open false ceiling, but the OD is the most dominant factor for all the other conditions. Therefore, the method using the SAHRR and the evacuation time map was very useful to effectively and comprehensively evaluate the operator habitability for the various input parameters in the event of MCB fires for the reference MCR.

• 한국안전학회지
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• 제38권6호
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• pp.72-78
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• 2023

The purpose of this paper is to derive a quantified approach for Operator Manual Actions (OMAs) based on the existing fire Human Reliability Analysis (HRA) methodology developed by the Korea Atomic Energy Research Institute (KAERI). The existing fire HRA method was reviewed, and supplementary considerations for OMA quantification were established through a comparative analysis with NUREG-1852 criteria and the review of the existing literature. The OMA quantification approach involves a timeline that considers the occurrence of Multiple Spurious Operations (MSOs) during a Main Control Room Abandonment (MCRA) determination and movement towards the Remote Shutdown Panel (RSP) in the event of a Main Control Room (MCR) fire. The derived failure probability of an OMA from the approach proposed in this paper is expected to enhance the understanding of its reliability. Therefore, it allows moving beyond the deterministic classification of "reliable" or "unreliable" in NUREG-1852. Also, in the event of a nuclear power plant fire where multiple OMAs are required within a critical time range, it is anticipated that the OMA failure probability could serve as a criterion for prioritizing OMAs and determining their order of importance.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.112-116
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• 2008

The combustion properties of sandwich panels were tested according to ISO 13784-1(Room Corner Test for Sandwich panel building systems) method to supplement ISO 9705 Room corner test, and analyzed comparatively. Several variables including heat release rate, smoke production rate, FIGRA, SMOGRA, thermal configuration, visual check lists and so on, were analyzed for four materials on sandwich panel systems. Finally, Fire performances of test results on each material by ISO 13784-1 are categorized by applying to the classification system of both EN 13501-1 and Eurefic research program

• 한국안전학회지
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• 제18권4호
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• pp.71-77
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• 2003

To inject fresh air into a fire room, Positive Pressure Ventilation (PPV) can be used and the blower of PPV increases inside pressure of the room. It makes high flow rate of products of combustion, smoke and heat from the structure, and it is very helpful to fireman on the fire extinguishing work. The flame moves to the direction of airflow and the temperature of flame can be decreased rapidly. In this experiment, a water mist system is applied to PPV to increase the effectiveness, and various effective factors are studied. n-Heptane and pine wood stick were used as fuel. Temperatures at the above and behind the combustion pan were strongly reduced by the water mist system and by the convective cooling with airflow. The smoke density was also decreased by PPV with water mist system and it can be explained by the absorption of smoke particles on the water mist droplet and by the strong exhausting effects of mobile fan.

• 한국화재소방학회논문지
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• 제34권4호
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• pp.22-28
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• 2020

복합소재 고체 가연물의 화재발생시 발생되는 열방출률을 ISO 9705 룸코너 시험을 통해 측정하였고 Fire dynamics simulator (FDS)에서 제공하는 열방출률 예측모델을 이용하여 전산해석을 수행하였다. 복합소재 고체 가연물로는 PU폼과 PP, 철재로 대부분 구성되어있는 영화관 의자를 선정하였다. FDS에서 제공되는 열방출률 예측방법을 단순모델과 열분해 모델로 구분하고 각각의 모델을 적용하여 동일한 조건에서 전산 해석한 결과, 열분해 모델을 통해 예측된 열방출률과 화재성장율이 단순모델을 이용하는 경우에 비해 ISO 9705 룸 코너 시험을 통해 측정된 결과와 잘 일치함을 확인할 수 있었다.

• 한국화재소방학회논문지
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• 제21권3호
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• pp.15-23
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• 2007

일반주택 화재시 가연성이 높은 폴리우레탄폼 소재의 소파가 연소될 때 다량의 독성가스가 포함된 연기가 발생한다. 이 경우 실내거주자는 고온의 연기와 독성가스로 인해 피난의 어려움을 겪고, 극단적인 경우 사망에 이르게 된다. 본 연구에서는 다세대주택 화재시 계단실 개구부의 개폐조건이 화재실과 계단실의 화재특성에 미치는 영향을 조사하기 위하여 CFD 시뮬레이션을 수행하였다. 화재실험에서 얻어진 유동장의 온도, 일산화탄소 농도 및 연기가시거리의 자료를 분석하여 화재안전한계 기준값과 부분유효량에 근거한 화재위험평가를 하였다. 화재실의 경우, 온도와 일산화탄소 농도는 각각 최대 $290^{\circ}C$와 4,740 ppm이며, 온도에 의한 거주자의 불능상태 도달시간은 발화 후 약 144초이다. 계단실의 경우, 창문이 개방된 경우의 온도와 일산화탄소 농도는 화재안전한계 기준 값 이하로서 개방되지 알은 경우 보다 크게 감소되었다. 또 계단실의 연기가시거리는 개방된 경우가 개방되지 않은 경우보다 화재안전한계 기준 값에 더 빨리 도달되었다. 결론적으로 다세대주택 계단실의 개구부를 개방할 경우 거주자의 화재위험 가능성은 낮아진다.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2005년도 공동추계학술논문발표회 논문집
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• pp.191-195
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• 2005

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2003년도 추계학술논문발표회논문집
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• pp.3-8
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• 2003

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1998년도 추계학술발표회 논문 초록집
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• pp.97-99
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• 1998

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2003년도 춘계학술논문발표회논문집
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• pp.59-65
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• 2003