• Fire Science and Engineering
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• v.17 no.3
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• pp.61-73
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• 2003

Most of the accidents occurred from the chemical plants are related to the catastrophic gas release events when the large amount of toxic materials is leaked from its storage tank or transmitting pipe lines. In this case, the greatest concerns are how the spreading behaviors of leakages are depended on the ambient conditions such as air stability and other environmental factors. Hence, we have focused on the risk assessments and consequential analysis for chlorine as an illustrative example. As appeared in the result, Fire & Explosion Index depicted it a bit dangerous with presenting the comprehensive degrees of hazard 90.7. And as a result of Phast6.0/ALOHA, the trends of each scenario appeared considerably identical although there are some differences in the resulting effects according to the input data for the Gas Model. The consequence analysis is performed numerically based on the dense gas mode. In the future, using more correct input data, material properties, and topographical configuration, the method of this research will be useful for the guideline of the risk assessment when the release of toxicants breaks out.

• Fire Science and Engineering
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• v.33 no.5
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• pp.7-12
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• 2019

To investigate the influence of the char layer formed during the combustion process on the pyrolysis of wood combustibles, ISO 5660-1 cone calorimetry experiments and Fire dynamics simulator (FDS) simulations were performed, and the results from these two methods were compared. The wood combustible selected as the fuel for this study, Douglas fir, has been widely used for the production of building materials, furniture, etc. The heat release rate (HRR) measured from the cone calorimetry experiment was in good agreement with the result predicted by the FDS simulation. However, the FDS simulation failed to predict the heat released by the smoldering combustion process, due to the absence of the char surface reaction in the model. The FDS simulation results clearly indicate that the char layer formed on the surface of combustibles produces a thermal barrier which prevents heat transfer to the interior, thickening the thermal depth and thus reducing the pyrolysis rate of combustibles.

• Journal of Korean Society of Forest Science
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• v.85 no.1
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• pp.66-75
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• 1996

This study was carried out to examine the forest fire effect on water storage characteristics in the forests. Water storage capacity of the burned area was analyzed by several major factors, such as soil pore, maximum water content, effective water storage, and percolation rate. The results obtained from the analysis of major factors are as follows; The deeper soil depth, the less total pore, coarse pore, effective water storage, and percolation rate. However, fine pore increased slightly in both burned area and control plot. As compared with control plot, burned area showed lower percolation rate, coarse pore, and effective water storage, but higher values of fine pore. Directly after forest fire, the soil pore is little affected. But as the time passes, top soil structure changes and soil pore also is affected even in a deep soil. Estimated effective water storage was lower at top soil of Namcheon and at deep soil of Namha in all the burned areas, but slowly decreased in deep soil compared to control plots. Therefore it was concluded that forest water storage capacity was greatly affected by the forest fire.

• Journal of Fashion Business
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• v.24 no.3
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• pp.30-39
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• 2020

This study was conducted to identify problems in domestic flame-retardant performance specifications. Currently, the domestic wallcovering anti-inflammatory regulations are not prepared for damage caused by smoke, with the carbonized area as the main function. In particular, given that smoke is the main cause of human casualties and injuries in a fire, it is reasonable that the flame density and toxicity of the wallcovering should also be the main performance indicators. The scope and method of research in this study were as follows. First, a prior study related to fire on various wallcoverings was considered. Second, it raised questions about the effects of smoke in the event of a fire and domestic anti-inflammatory performance tests. Third, textile wallcovering samples were manufactured with viscose rayon for experimental verification of the problems and tested by Korean and EU standards without flame retardant processing to analyze the differences between each regulation. Fourth, the performance of flame retardant wallcovering according to Korean standards was evaluated using smoke density and harmful gas testing methods. The results of each test were as follows. Non-fire retardant wallcovering was rejected by Korea standards. However, B-s1.d0 in Europe. Smoke density testing and harmful gas by domestic combustion processing on the same sample showed that the smoke density increased about 4.3 times more than before, and the harmful gas test showed that the suspension of the post-processing sample slowed earlier than the non-processed sample.

• Journal of the Korean Wood Science and Technology
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• v.41 no.6
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• pp.559-565
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• 2013

This study evaluated the ability of white and brown rot fungi to decompose fire retardant-treated wood by measuring mass loss. Anti efficacy of FRT against sapstain and mold fungi was evaluated. Wood was treated with liquid sodium silicate and boric acid, ammonium borate, di-ammonium phosphate. Retardant treated wood was then subjected to fungal decay resistance tests performed according to KS standard method using a brown-rot fungus, Fomitopsis palustris and white rot fungus Trametes versicolor. Aspergillus niger, Penicillium funiculosum, Rhizopus nigricans, Aureobasidium pullulans, Tricoderma virede fungi were used anti-sapstain and mold test. Boron and phosphorus chemicals used in this study increased the resistance of fire retardant treated wood against both fungal attack. Anti mold and sapstain efficacy of the fire retardant treated wood was excellent but there were difference depend on mold. After the liquid sodium silicate treatment, the second chemical treatment process could lead chemical fixation into wood, which effects decay resistance.

• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.493-510
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• 2021

Mineral wool is an insulation material commonly used in passive fire protection (PFP) systems on offshore installations. Insulation materials have only been considered functional materials for thermal analysis in the conventional offshore PFP system design method. Hence, the structural performance of insulation has yet to be considered in the design of PFP systems. However, the structural elements of offshore PFP systems are often designed with excessive dimensions to satisfy structural requirements under external loads such as wind, fire and explosive pressure. To verify the structural contribution of insulation material, it was considered a structural material in this study. A series of material tensile tests was undertaken with two types of mineral wool at room temperature and at elevated temperatures for fire conditions. The mechanical properties were then verified with modified methods, and a database was constructed for application in a series of nonlinear structural and thermal finite-element analyses of an offshore bulkhead-type PFP system. Numerical analyses were performed with a conventional model without insulation and with a new suggested model with insulation. These analyses showed the structural contribution of the insulation in the structural behaviour of the PFP panel. The results suggest the need to consider the structural strength of the insulation material in PFP systems during the structural design step for offshore installations.

• The Korean Journal of Emergency Medical Services
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• v.26 no.3
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• pp.137-148
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• 2022

Purpose: This study aims to provide essential data for developing educational methods and content, tailored for the prehospital field situation, by analyzing the effects of education regarding the management of cardiac arrest. Methods: This study is a primitive experimental study of 55 new firefighters in C Fire Service Academy. Data were collected from the training which was imparted using the CPR virtual reality simulation program (CBS 2.0) in accordance with COVID-19 quarantine rules and social distancing. Data were analyzed utilizing SPSS version 25.0. Results: After VR simulation training, knowledge about performing CPR (14.85) and self-efficacy (4.12) were significantly high (p<.001). Learning immersion was also high (3.99±0.59), but learning satisfaction was even higher (4.34±0.62). Depending on the recruitment field, firefighters showed higher learning immersion (4.04±0.58 vs 3.68±0.63) and self-efficacy (4.16±0.55 vs 3.91±0.84) than 119 EMTs' but, there was no significant difference between them. In contrast, The quality of performance of CPR by EMT's was significantly higher than that of firefighters (p=.025). Depending on previous simulation experience, there was no significant difference among dependent variables. Conclusion: Virtual reality simulation shows positive results in learning immersion, learning satisfaction, self-efficacy, and performance of CPR. Therefore, we propose that virtual reality simulation training can be a new educational paradigm.

• Journal of the Society of Disaster Information
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• v.20 no.3
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• pp.593-600
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• 2024

Purpose: In this study, fundamental research was conducted to capture sparks generated during the arc welding process. Method: To this end, a mock-up collection device was developed, consisting of a blower for suction, a nozzle, and a filter and magnet at the suction point. To analyze the correlation between the shape of the filter and its magnetic properties, the porosity and pore size of both carbon filters and Colgate filters were quantified under conditions of a welding machine capacity of 1,800W and a welding time of 70s. The collection efficiency of sparks was calculated for magnetic strengths of 2.6, 3.4, and 4.05kgf. Result and Conclusion: As a result, empirical formulas were derived for the blower's suction capacity, magnetic strength, porosity, and pore diameter for capturing sparks, with experimental results confirming consistency within ± 10%. The findings of this study are expected to provide a quantitative design approach for collection devices that can minimize the risk of fire spread associated with welding operations at construction sites.

• Journal of the Korean Institute of Gas
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• v.3 no.1
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• pp.21-26
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• 1999

Chemical plant's fire and explosion does not only damage to the chemical plants themselves but also damage to people in or near of the accident spot and the neighborhood of chemical plant. For that reason, Chemical process safety management has become important. One of safety management methods is called 'the quantitative analysis', which is used to reduce and prevent the accident. The results of the quantitative analysis could be used to arrange the equipments, evaluate the minimum safety distance, prepare the safety equipments. In this study we make the computer program to make easy to do Quantitative analysis of the accident. The output of the computer program is the magnitude of fire(pool fire and fireball) and explosion(UVCE and BLEVE) effects. We used the thermal radiation as a measure of fire magnitude and used the overpressure as a measure of explosion magnitude. In case of BLEVE, the fly distance of fragment can be evaluated. Also probit analysis was done in every case. As the case study, Buchun LPG explosion accident in Korea was analysed by the program developed. The simulation results showed that the permissible distance was 800m and probit analysis showed that 1st degree bum, 2nd degree burn, and death distances are 450, 280, 260m, respectively the simulation results showed the good agreement with the results from SAFER PROGRAM made by Dupont.

• Journal of the Korean Institute of Gas
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• v.24 no.4
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• pp.18-24
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• 2020

The purpose of this study is to validate thermal hinderance effects, i.e., feasibilities, of fire-proof structure for LPG tank exposed to fire from adjacent burning building. The panel materials suggested for the fire-proof structure are (1) 10 mm-thick wood, (2) wood with fireproof coating, (3) 75 mm-thick Expanded Polystyrene, (4) 75 mm-thick glass wool filled sandwich panel, and (5) 75 mm-thick autoclaved lightweight concrete. The square planar fire source of 1 ㎡, a matrix of nozzles releasing 120-140 g/s of LPG, is used to heat up the wall and the tank beyond, mimicking heat transfer from burning exterior wall finishes. The feasibility is tested by inspecting structural integrity after test, and then by examining temperatures at both sides of panels and tank's front surface as well as heat fluxes. As a result, it can be concluded that, among the suggested sample materials, fire-proof wall with ALC panel only showed the feasibility for explosion prevention with the proven evidences of structural integrity and least increase in temperature of tank.