• Journal of the Korean Society of Safety
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• v.34 no.4
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• pp.22-31
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• 2019

The flammable liquid conductivity is an important factor in determining the generation of electrostatic in fire and explosion hazardous areas, so it is necessary to study the physical properties of flammable liquids. In particular, the relevant liquid conductivity in the process of handling flammable liquids in relation to the risk assessment and risk control in fire and explosion hazard areas, such as chemical plants, is classified as a main evaluation item according to the IEC standard, and it is necessary to have flammable liquid conductivity measuring devices and related data are required depending on the handling conditions of the material, such as temperature and mixing ratio for preventing the fire and explosion related to electrostatic. In addition, IEC 60079-32-2 [Explosive Atmospheres-Part 32-2 (Electrostatic hazards-Tests)] refers to the measuring device standard and the conductivity of a single substance. It was concluded that there is no measurement data according to the handling conditions such as mixing ratio of flammable liquid and temperature together with the use and measurement examples. We have developed the measurement reliability by improving the structure, material and measurement method of measuring device by referring to the IEC standard. We have developed a measurement device that is developed and manufactured by itself. The test results of flammable liquid conductivity measurement and the data of the NFPA 77 (Recommended Practice on Static Electricity) Annex B Table B.2 Static Electric Characteristic of Liquids were compared and verified by conducting the conductivity measurement of the flammable liquid handled in the fire and explosion hazardous place by using Measuring / Data Acquisition / Processing / PC Communication. It will contribute to the prevention of static electricity related disaster by taking preliminary measures for fire and explosion prevention by providing technical guidance for static electricity risk assessment and risk control through flammable liquid conductivity measurement experiment. In addition, based on the experimental results, it is possible to create a big data base by constructing electrostatic physical characteristic data of flammable liquids by process and material. Also, it is analyzed that it will contribute to the foundation composition for adding the specific information of conductivity of flammable liquid to the physical and chemical characteristics of MSDS.

• Fire Science and Engineering
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• v.23 no.3
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• pp.11-16
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• 2009

This paper describes a detecting method for indication of an electric accident in electric equipments. For that, loads of electric equipment is consisted of incandescent lamps. And the electric accident is simulated a tracking test apparatus according to KS C IEC (Korea Standard C International Electrostatic Commission) 60112 at some part of the simulation of the electric equipment. Simulated electric accident is occurred from static states through discharge in progress, carbon formation to tracking breakdown. The total current of electric equipments is measured and analyzed for detecting of indication of the electric accident using a current monitor. For the result, as an electric accident processed, as a current pulse is bigger and a ratio of appearance also increases at certain part of current waveforms. And standard deviation and probability distribution for certain part of current waveforms show remarkably different pattern in each step of electric accident which is irrespective of amount of load.

• Fire Science and Engineering
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• v.31 no.3
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• pp.19-24
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• 2017

Flammable substances are used in laboratories and industrial process. The flash point (FP) is one of the most important physical properties used to determine the potential for characterizing the fire and explosion hazard of liquids. The FP data at 101.3 kPa were measured for the binary systems {toluene+ethylbenzene}, {methlycyclohenxane+ethylbenzene} and {n-heptane+ ethylbenzene}. The experiments were performed according to the standard test method (ASTM D 3278) using a SETA closed cup flash point tester. The measured FPs were compared with the values predicted using the following activity coefficient models: Wilson, Non-Random Two Liquid (NRTL), and UNIversal QUAsiChemical (UNIQUAC). The average absolute deviation between the predicted and measured lower FP was less than 1.74 K.

• Fire Science and Engineering
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• v.32 no.1
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• pp.1-6
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• 2018

The flash point is one of the most important parameters used to characterize the ignition and explosion hazards of liquids. Flash points were measured for several binary systems containing toluene, including {methanol+toluene}, {ethanol+toluene}, and {1-propanol+toluene}. Experiments were performed according to the standard test method using a SETA closed cup flash point tester. The measured flash points were compared with the predicted values calculated using the following $G^E$ models: Wilson, NRTL, and UNIQUAC. The average absolute deviation between the predicted and measured lower flash point was less than 1.69 K.

• Journal of Korean Society of Steel Construction
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• v.19 no.4
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• pp.425-434
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• 2007

The SC (steel-concrete) composite column was developed to take advantage of the relative economy of using concrete as opposed to steel in carrying large compressive forces. As the SC composite column is pre-fabricated, its use can minimize laborand can speed up the erection of a steel building. In this study, an experiment was conducted to analyze the influence of several parameters, such as the load ratio, the concrete ratio of an area, and its performance with or without fire protection, on the performance of the SC composite column. This paper proposes that the calculation of the strength reduction ratios of columns be done by increasing the temperature. Theoretical equations were used to evaluate the effectiveness of the fire resistance of the SC composite column, and the results of the test and analysis were compared. The fire resistance of the SC composite column was increased by decreasing its load ratio, but the concrete ratio of an area has minimal influence on the fire resistance of the SC composite column.

• Fire Science and Engineering
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• v.23 no.3
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• pp.131-137
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• 2009

This study measured smoke control damper leaking amount of condition of various kinds examination regarding AMCA Standard 500-D-98. As result of study establish because smoke control damper leaking amount performance curve that use tester data of engineering applies right design method of smoke control system and test method design, drawing examination, performance test and do so that right comprehension and performance about skill may be defined. Also user wishes to prove performance of smoke control system and construct smoke control system of reliable performance-based design derive smoke control damper quality improvement continuously selection of smoke control damper by performance judgment of performance curve.

• Fire Science and Engineering
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• v.30 no.4
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• pp.121-127
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• 2016

This study analyzed the structural and electrical characteristics of an iron fittings type Corrugated Stainless Steel Tubing (CSST) damaged by the Primary Current Injection Test System (PCITS). CSST consists of cladding, tube, nuts, clamp ring, flare cap, socket, and ball valve. For an evaluation of the dielectric withstand voltage, the area between the live part and non-live part of the CCST shall withstand a voltage of 220 V AC for one minute. For an evaluation of the insulation performance by 500 V DC, it is required that the insulation exceed more than $1M{\Omega}$ before the temperature rise test, $0.3M{\Omega}$ after the test. Although the average resistance of the product was $11.5m{\Omega}$, that of the product damaged at a current of 130 A by the PCITS was $11.50m{\Omega}$. Furthermore, parts of the cladding were melted and black smoke appeared when a current of 130 A applied for 10 s. After 60 s, most parts were heated and turned red. At 120 s, the parts that turned red had widened. Although it did not form a normal distribution because the P value was 0.019 with a confidential interval of 95%, it revealed outstanding characteristics with an AD (Anderson-Darling) value of 0.896 and a standard deviation of 0.5573.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.182-193
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• 2022

Purpose: By measuring and evaluating the risk of biodiesel through non-volatile residue (NVR) and flash point and explosion limit measurement at a specific temperature according to ASTM test standards, the risk of chemical fire causative substances is identified and a universal evaluation method By derivation and securing the risk-related data of the material, it can be used for the identification and analysis of the cause of the fire, and it can be applied to the risk assessment of other chemical substances Method: In order to measure the risk of biodiesel, it was measured using the non-volatile residue(NVR) measurement method, which measures how much flammable liquid is generated at a specific temperature. Heating was tested by applying KS M 5000: 2009 Test Method 4111. In addition, the flash point was measured using the method specified in ASTM E659-782005, and the energy supply method was measured using the constant temperature method. In addition, the explosion limit measurement was conducted in accordance with ASTM E 681-04 「Standard test method for concentration limits of flammability of chemicals(Vapors and gases)」 test standard. Result: As a result of checking the amount of combustible liquid by the non-volatile residue (NVR)measurement method, the non-volatile residue(NVR) of general diesel when left at 105±2℃ for 3 hours was about 30% (70% of volatile matter) and about 4% of biodiesel. In addition, similar results were obtained for the non-volatile residue(NVR)heating temperature of 150±2℃, 3 hours and 200±2℃ for 1 hour, and white smoke was generated at 200℃ or higher. In addition, similar values were obtained as a result of experimentally checking the explosion (combustion) limits of general diesel, general diesel containing 20% biodiesel, and 100% biodiesel. Therefore, it was confirmed that the flammability risk did not significantly affect the explosion risk. Conclusion: The results of this study suggested the risk judgment criteria for mixtures through experimental research on flammable mixtures for the purpose of securing the effectiveness, reliability, and reproducibility of the details of the criteria for determining dangerous substances in the existing Dangerous Materials Safety Management Act. It will be possible to provide reference data for the judgment criteria for flammable liquids that are regulated in the field. In addition, if the know-how for each test method is accumulated through this study, it is expected that it will be used as basic data in the research on risk assessment of dangerous substances and as a basis for research on the determination of dangerous substances.

• Fire Science and Engineering
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• v.31 no.3
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• pp.11-18
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• 2017

In this study, a non-halogen type organic-inorganic hybrid flame retardant sol, which can impart flame resistance to synthesize silicate of inorganic material and silane coupling agent of organic material by a sol-gel method, were newly manufactured. The addition of flame retardant will prevent loss of life in a fire because smoke from the flammability of interior finishing materials used as the construction materials poses a major danger. The smoke density measurement standard based on flame retardant performance standards, experiments were conducted according to the test equipment and procedures of ASTM E 662. The non-flaming mode experiment and the flaming mode experiment were conducted to confirm the performance of the manufactured flame retardant sol. As a result, the manufactured flame retardant sol improved the physical properties and heat resistance of existing flame retardants, and decreased the smoke production of the fire. Therefore, it may be possible to reduce the damage caused by smoke and expand the applications to various interior finishing materials.

• Fire Science and Engineering
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• v.28 no.4
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• pp.104-111
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• 2014

The purpose of this study is to investigate the CPR within ambulance. The Subjects were 890 emergency medical technicians in fire department in Gyeonggido. After continuing education program, the emergency medical technicians completed the questionnaires from January to February, 2012. Questionnaire consisted of demographic characteristics, method of chest compression (one handed or two handed), chest compression - ventilation ratio, and hands only CPR. Data were analyzed by frequency analysis and Chi-square test, t-test. One-way analysis of variance (ANOVA) was followed by Scheffe post-hoc test to analyze changes in all parameters between all groups. One handed chest compression accounted for 14.0% and two handed chest compression accounted for 86.0%. Hands only CPR accounted for 71.7% and standard CPR (30:2) accounted for 28.3%. In order to perform the high quality CPR, as least three persons must be dispatched in the ambulance. The flexible management of manpower may improve the survival from the cardiac arrest. A systemic approach for educating and training EMT's in CPR is needed.