• Journal of the Korean Institute of Gas
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• v.16 no.6
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• pp.7-16
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• 2012

Combustion Toxic Effects among several factors of risk encountered during fire are important in the evacuation and final survival, and they are broader and fatal than the direct damages caused by flame. Most studies on fire toxicity until the present are limited to fatality, mainly deaths by fire through pathological research. In this study, it is conducted as a fundamental experiment to address 3 principles of animal experiment and to provide an alternative test to animal testing that is regulated by national building codes and it was conducted through approval by the animal testing ethics committee. Hence, in this study average time of activity stop was measured after directly inhaling toxic gases (HCN) to laboratory animals (mice) through gas toxicity test (KS F 2271) for major asphyxiating gases(HCN) which are produced during fire combustion. effects of Combustion toxic gases on body were quantitatively analyzed through changes in internal organs and hematological analysis, and electrophoresis of a single cell of these laboratory animals. Biological conclusion of combustion toxicology is drawn through approaches (pathological examination, blood test, blood biochemical test, electrophoresis analysis of single cell) which could not confirmed in existing gas toxicity test.

• Fire Science and Engineering
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• v.22 no.2
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• pp.30-37
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• 2008

We have performed the inflammability test for various flooring materials through a radiant heat panel tester by using the specification KSISO 9239-1 (an examination method of flooring materials) that has been set as an international standard for the fire prevention means of interior flooring materials. We have measured the flame spread distance, critical heat flux and smoke density generated by the fire of various flooring materials while using the radiant heat panel tester. The measurement result has shown the burning characteristics different from each other by the respective flooring materials and we could see that the surface materials and construction elements influence greatly on the heat release and smoke generation. We could see that the evaluation method above is an important test method in evaluating the critical heat flux, smoke generation and flame spread distance that are Important factors in studying for fire risks and it is judged that setting and applying a fire evaluation method of flooring materials suitable for the domestic construction use would be relevant.

• Journal of Korean Tunnelling and Underground Space Association
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• v.6 no.2
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• pp.129-139
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• 2004

The several assumptions and design parameters to determine the ventilation rate in tunnel ventilation system were examined. In longitudinal ventilating tunnel, the ventilation rate has been determined by the critical velocity above which the smoke propagation to the upstream of ventilating air is prevented. Based upon the examination of assumptions and experimental results, we suggested the improved method to determine the critical velocity. In transverse ventilating tunnel, we found that the ventilation rate has been determined in accordance with the custom rather than fire-smoke dynamics such as the critical velocity in the longitudinal ventilating tunnel. It is because the ventilation rate in the transverse ventilation system has been determined by considering only the ventilation of contaminant by vehicle. To improve the ventilation design parameters based upon the fire-smoke dynamics, we conducted model tunnel fire experiments. From the experimental results, smoke propagating distance and smoke filling were suggested as the design parameter to determine the ventilation rate in transverse ventilating tunnel. And tunnels in Europe designed by the custom is found to have the dangerous nature in view of fire safety.

• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.43-51
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• 2012

This study was carried out to observe the impacts of a mouse's inhalation of toxic gas SO2 generated from combustion on its organs by different concentrations. As for research methods: First, after concentrations of SO2 generation from combustion had been set to three: low (10.4 ppm), middle (24.9 ppm) and high (122 ppm) through Gas Toxicity Testing Method (KS F 2271) and SO2 combustion gas was exposed to eight mice in each concentration. Five mice that were able to move based on LD50, a criterion, which sets the down time of a mouse's average behaviors to over 9 minutes, were randomly selected in each concentration, and they were set up as the subjects of the study on toxicity bio-markers. Second, tissues were taken from heart, liver, lungs, spleen and the thymus gland of the mice selected in each concentration and a pathological examination of them was carried out. As a result, microvascular congestion appeared in the heart, and cell necrosis, cortex congestion and tubule medulla congestion, etc. in each concentration were observed in addition to vascular congestion in liver, lungs, spleen and the thymus gland. Also, it was found that the higher the concentrations of SO2 exposure is, the greater, the changes in the organs get. Through this study, SO2 of various toxic gases generated from fire turned out to affect the tissues of each organ of a mouse, it is expected that the toxic gases may greatly affect human body in case of actual fire, and this study is evaluated as having a significance as a basic data on inhalation toxicity assessment of toxic substances generated in combustion.

• Fire Science and Engineering
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• v.33 no.5
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• pp.28-36
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• 2019

In the present study, the effects of supply gas and water mist on the heptane pool fire extinguishing performance were investigated using the full cone and hollow cone twin-fluid atomizers. Air or nitrogen of 30 lpm (Liter per minute; L/min) was used as the supply gas, and the experiments were conducted under the water flow rate conditions of 0 lpm (i.e., discharge of air or nitrogen only) and 0.085 lpm (i.e., discharge of water mist with supply gas). Experimental results confirmed that the use of water mist discharge with the supply gas and full cone spray pattern reduced the fire extinguishing time as compared to that of only supply gas discharge and hollow cone spray pattern. In addition, for the discharge of water mist using the full cone twin-fluid atomizer, water mist significantly affected fire extinguishing performance, whereas the effect of the supply gas was less pronounced. On the other hand, for the discharge of water mist using the hollow cone twin-fluid atomizer, the fire extinguishing time was remarkably reduced by the supply of nitrogen, as compared with that of air, indicating that the supply gas as well as water mist can significantly affect fire extinguishing performance.

• Journal of the Optical Society of Korea
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• v.15 no.4
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• pp.340-344
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• 2011

Airborne infrared techniques have been used in wild land fire management for decades. This paper describes a kind of infrared scanning system based on a rotating drum with a tilted porthole underside the plane nose. This design increases the stability of the mechanism system, reduces air resistance and protects inner parts. Aberration characteristics of a tilted ellipsoid porthole are analyzed and an effective solution is invented which makes the system achieve $30^{\circ}$ field of regard. The system's ultimate value of modulation transfer function is near the diffraction limit, which indicates that the performance of the rotating optical system meets the imaging requirements.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.227-228
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• 2009

This study proceeded to find the optimum mixing rate of a high strength concrete with 80MPa of the contribution and composite effect on the resistance to fire of the fibers were analyzed and the corresponding results were exploited to derive practical mix proportions. Also proceeded to propriety examination of limit value for optimum operating condition.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.71-72
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• 2017

The oyster shell is lightweight and exhibits strength characteristics similar to sand. In this study, mortar specimens were fabricated by crushing them and processed to 5mm or less of the fine aggregate standard, and examined the fire resistance of the mortar according to changes in particle size distribution. In this experiment, seven particle size distribution conditions were tested. In addition, the mixing ratio was fixed at 1: 3, and the experiment was conducted in terms of the volume ratio because the densities of sand and oyster shells were different.

• Corrosion Science and Technology
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• v.20 no.5
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• pp.242-248
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• 2021

Unforeseen failures of boilers in power plants may affect the continuation of electricity generation. Main failures in boilers are influenced by the tube material, tube position, boiler service temperature and pressure, and chemical composition of the feed water and coal. This investigation was intended to find answers on the causes and mechanism of failure of the fire-side boiler water-wall tubes, due to perforation and corrosion. The tube conformed to the material requirements in terms of its chemical composition and hardness. Microscopic examination showed ferrite and pearlite indicating no changes in its microstructure due to the temperature variation. SEM test showed a single layer and homogenous film density particularly on the area far from perforation. However, layers of corrosion product were formed on the nearby perforation area. EDX showed that there were Na, Ca, S, and O elements on the failed surface. XRD indicated the presence of Fe₂O₃ oxide. The failure mechanism was identified as a result of significant localized wall thinning of the boiler water wall-tube due to oxidation.

• Herbal Formula Science
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• v.13 no.2
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• pp.125-140
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• 2005

This report describes 48 studies related to the use of Bulbus Fritillariae main blended prescriptions from Donguibogam. The following conclusions were reached through investigations on the prescriptions that use Bulbus Fritillariae as a key ingredient. All kinds of infection in a cough and the malignant tumor recorded the largest number of clinical frequency of the prescriptions in therapeutic use when Bulbus Fritillariae was taken as a principle medicine. The Prescriptions are compounded with Bulbus Fritillariae as a principle medicine can aplly to respiratory disease, eye disease, nose and ear disease, throat disease, a boil. Various pathogenic factors such as consumptive disease, phlegm, phlegm-fire, invasion by wind, affective by cold, fire, dyspepsia-fire are put to practical use. The dosage of Bulbus Fritillariae is 5 bun (about 1.88g) to 1 lyang(about 37.5g), however 1 jeon(about 3.75g) has been taken the most for clinical application. With examination the formulae of presciptions containing Bulbus Fritillariae, I found the basic prescriptions as well as the medicines are in conjunction with Bulbus Fritillariae and the theoretic grounds of formula in combining Bulbus Fritillariae as a group of medicine for presciption through this reseach.