• Journal of the Korean Institute of Gas
• /
• v.16 no.6
• /
• pp.128-135
• /
• 2012

In this paper, we proposed a system and a scenario to raise efficiency of gas safety management by developing wireless ZigBee communication modules, smart-home gas safety appliances and the system suitable for gas safety. Our designed system consists of a micom gas meter, an automatic extinguisher, sensors, and a wall-pad. A micom-gas-meter monitors gas flow, gas pressure, and earthquake. An automatic fire extinguisher checks combustible gas leaks and temperature of $100^{\circ}C$(cut off) and $130^{\circ}C$(fire). Sensors measure smoke and CO gas. In our novel system, a micom-gas meter cut off inner valve with warnings, an automatic fire extinguisher cut off middle valve and spray extinguishing materials, and sensors generate signals when detecting smoke and CO and then take a next action. Gas safety appliances and sensors automatically takes measures, and transmit those information to a wall-pad. The wall-pad again transmits real time information to server. Users can check and manage gas safety situations by connecting BcN server through web or mobile application. We hereby devised scenarios for gas safety and risk management based on the smart, and demonstrated their efficiency through test applied to filed.

• Fire Science and Engineering
• /
• v.34 no.1
• /
• pp.11-17
• /
• 2020

As performance-based design (PBD) has a direct impact on evacuation safety assessments, designing fire scenarios based on real fire tests is essential. To improve the reliability of the PBD for fire safety in multiplexes, information on fire behavior, such as heat release rate (HRR) and fire spread rate, are provided in this study by conducting a standard fabric flammability test. To this end, several chairs were arranged in a pattern that resembled a theater-style seating. The peak HRR and heating value per unit mass for each chair ranged from 415 kW to 988 kW and 15.2 MJ/kg to 23.8 MJ/kg, respectively. The heating values per unit mass of the new and old chairs were 23.6 MJ/kg and 16.7 MJ/kg, respectively. As the quantity of plastic and cushioning materials in the new chairs was more than that of the old ones, the new chairs were more vulnerable to fire hazards. Furthermore, when the chairs were arranged in a line, the fire spread rate was observed to be 0.39-0.42 m/min, regardless of the ignition location. Finally, a fire growth curve showing the peak HRR and fire spread rate was also demonstrated.

• Journal of Energy Engineering
• /
• v.17 no.4
• /
• pp.212-217
• /
• 2008

This study carried out the safety evaluation of non-refillable butane can for portable gas range equipped with relief valve for prevention of explosion. The can is heated by electric heater at the real using condition and the extreme condition after installing at a portable gas range for checking the operating pressure and the evaluating suitability of releasing flux. And the possibility of fire or explosion was tested when the gas was released from the relief valve at the real condition. As a result of this safety evaluation test, a non-refillable butane can with relief valve prevents the can from exploding by control of internal pressure.

• Journal of the Korea Safety Management & Science
• /
• v.17 no.2
• /
• pp.117-127
• /
• 2015

This study investigated the smoke blocking and control systems for the safety of residents evacuation and for the prevention of smoke spread through the central corridor in the event of central corridor type of intelligent building fire. We offered additional ways of utilizing smoke ventilators and intake ventilation equipment and utilized CFD-based fire simulation program(FDS Ver.5.5.3) in order to analyze the effect. As a result, many differences in the smoke block effect, depending on the application of smoke ventilator and location of installation, was found. In addition, the result was found that larger effect was showed not in the case of application of smoke ventilator in central corridor only but application in fire room. The reason is that the smoke leakage is blocked primarily as air is flowed in the fire room through open door by operation of intake smoke ventilator in the public corridor and secondarily, the smoke leakage to the public corridor could be blocked as fire and smoke were released to the opened smoke ventilator continuously. Especially, the effect was maximized through complex interactions by applying smoke ventilator and intake ventilation equipment in corridor together rather than applying smoke ventilator and intake ventilation equipment independently. The proposed measure through this study shall be considered from architectural plan as one of ways for blocking from smoke spread to the central corridor in the central corridor type of intelligent building. In addition, flaws on regulation shall be established and supplemented.

• Journal of the Korean Institute of Gas
• /
• v.28 no.1
• /
• pp.85-99
• /
• 2024

As the proliferation of hydrogen electric vehicles accelerates, there is observed diversification in hydrogen refueling station models. This diversification raises safety concerns for different types of stations. This study conducted a quantitative risk assessment of a multi-vehicle hydrogen station, capable of simultaneously refueling cars, buses, and trucks. Utilizing Gexcon's Effects&Riskcurves Software, scenarios of fire and explosion due to hydrogen leaks were assessed. The study calculated the impact distances from radiative heat and explosion overpressure, and measured risks to nearby buildings and populations. The largest impact distance was from fires and explosions at dispensers and high-pressure storage units. High-pressure storage contributes most significantly to personal and societal risk. The study suggests that conservative safety distances and proper protective measures for these facilities can minimize human and material damage in the event of a hydrogen leak.

• Structural Engineering and Mechanics
• /
• v.80 no.6
• /
• pp.701-709
• /
• 2021

The paper aims at improving the understanding and mitigating the effects of tunnel fires that may breakout due to the burning fuel and/or explosion within the tunnel. This study particularly focuses on the behavior of the commonly used horse shoe geometry of tunnel systems. The problem has been obtained using an adequate well-established program incorporating the Lagrangian approach. A transient-thermo-coupled static structural analysis is carried out. The effects of radiation and convection to the outer walls of the tunnel is studied. The paper also presents the impact of the hazard on the structural integrity of the tunnel. A methodology is proposed to study the tunnel fire using a model which uses equivalent steel sheet to represent the presence of reinforcements to improve the computational efficiency with adequate validation. A parametric study has been carried out and the effect of suitable lining property for mitigating the fire hazard is arrived at. Detailed analysis is done for the threshold limits of the properties of the lining material to check if it is acceptable in all aspects for the integrity of the tunnel. The study may prove useful for developing insights for ensuring tunnel fire safety. To conduct such studies experimentally are tremendously costly but are required to gain confidence. But, scaled models, as well as loading and testing conditions, cannot be studied by many trials experimentally as the cost will shoot up sharply. In this context, the results obtained from such computational studies with a feasible variation of various combinations of parameters may act as a set of guidelines to freeze the adequate combination of various parameters to conduct one or two costly experiments for confidence building.

• Korean Chemical Engineering Research
• /
• v.57 no.2
• /
• pp.225-231
• /
• 2019

In Korea, the minimum separation distance between aboveground high-pressure natural gas pipeline and buildings is regulated by Korea gas safety (KGS) code. In this paper, The technical backgrounds for the revision of the KGS code related to the minimum separation distance was presented. A consequence-based approach was adopted to determine the minimum separation distance by a reasonable accident scenario, which was a jet fire caused by the rupture of one inch branch line attached the gas pipeline. Where, the higher thermal radiation flux threshold was selected for workers in industrial area than for people in non-industrial area, because the workers in industrial area were able to escape in a shorter time than the people in public. As result of consequence analysis for the accident scenario, we suggested the KGS code revision that the minimum separation distances between high-pressure natural gas pipeline installed above ground and buildings should be 30 meter in non-industrial area and 15 meter in industrial area. The revised code was accepted by the committee of the KGS code and now in effect.

• Journal of the Korean Institute of Gas
• /
• v.12 no.2
• /
• pp.25-31
• /
• 2008

Recently risk management based on a quantitative assessment is considered to improve the level of safety in Korea. This paper focuses on the procedure of the quantitative risk assessment for natural gas pipelines. For that purpose, the methods to estimate failure frequency based on failure causes from European Gas Pipeline Incident Data Group and BG Transco, to analyze consequence caused by fire, and to calculate individual risk and societal risk have been proposed systematically in this paper. Risk criteria of individual risk and societal risk have been proposed by considering the environment of pipeline route in Korea. The proposed procedure of quantitative risk assessment may be useful for risk management during the planning and building stages of a new pipeline, and modification of buried pipeline.

• Fire Science and Engineering
• /
• v.34 no.1
• /
• pp.18-25
• /
• 2020

In this study, the heat release rate of pipe insulation is analyzed by considering the installation status in accordance with the standards ISO 20632 and NFPA 274. The flame retardation rate was evaluated for six types of test samples: polyethylene foam covered with beaten silver (PE(S)), PE foam tapped (PE(N)), elastomeric closed cell thermal insulation (rubber), Japanese PE foam (PE(J)), Japanese polyurethane foam (PU(J)), and Japanese styro form (ST(J)) by EN 13501-1 and fire growth curve. The results show that PU(J), PE(J), and PE(N) were Class E and ultra-fast, NFPA 274 test standards for Class D and Fast, and PE(S) by ISO 20632 were Class C and Slow, and Rubber and ST(J) were Classes and Low. However, the changes in the time-averaged maximum heat release rate for each test standard (ISO 20632 and NFPA 274) to evaluate the flame retardation rate differed among identical materials. This means that the fundamental study is necessary to analyze the more accurate reasons.

• Journal of the Korean Institute of Gas
• /
• v.14 no.1
• /
• pp.37-41
• /
• 2010

The most important element for improving the process safety that occurs from the flare system installed to convert into safe materials by burning the inflammable or toxic gases within the process and this is specified in the API 521 Code so that the radiation does not cause a risk factor. The flames that occur from the flare stack holds the shape of jet fire due to the pressure and flow velocity of discharge gas. This study has identified the shape of flames by using the Chamberlain Model rather than the API 521 Code method, analyzing the radiation due to this.