• Applied Chemistry for Engineering
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• v.32 no.1
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• pp.102-109
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• 2021

Recently, an interest in risk calculation methods has been increasing in Korea due to the establishment of classification code for explosive hazardous area on gas facility (KGS CODE GC101), which is based on the international standard of classification of areas - explosive gas atmospheres (IEC 60079-10-1). However, experiments to check for leaks of combustible or toxic gases are very difficult. These experiments can lead to fire, explosion, and toxic poisoning. Therefore, even if someone tries to provide a laboratory for this experiment, it is difficult to install a gas leakage equipment. In this study we find out differences among actual experiments, CFD by using FLACS and calculation based on classification code for explosive hazardous area on gas facility (KGS CODE GC101) by comparing to each other. We develpoed KGS HAC (hazardous area classification) program which based on KGS GC101 for convenience and popularization. As a result, actual gas leak, CFD and KGS HAC are showing slightly different results. The results of dispersion of 1.8 to 2.7 m were shown in the actual experiment, and the CFD and KGS HAC showed a linear increase of about 0.4 to 1 m depending on the increase in a flow rate. In the actual experiment, the application of 3/8" tubes and orifice to take into account the momentum drop resulted in an increase in the hazardous distance of about 1.95 m. Comparing three methods was able to identify similarities between real and CFD, and also similarities and limitations of CFD and KGS HAC. We hope these results will provide a good basis for future experiments and risk calculations.

• Journal of the Korean Institute of Gas
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• v.15 no.1
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• pp.68-73
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• 2011

The systems in Korea regarding manufacture, storage, transport and use of hazardous materials are regulated by the related laws and ordinances. The number of accident from hazardous materials has recently decreased but the size of accident has increased according to the hazardous substances are greatly consumed and delivered. The results of analysis showed that most of accidents are caused by human problems and occurred frequently at unauthorized facilities. It is suggested that workers should be trained more and the strict regulation on unauthorized facilities is needed to reduce the accidents caused by hazardous materials.

• Journal of Sensor Science and Technology
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• v.32 no.2
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• pp.75-81
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• 2023

The significance of gas sensors has been emphasized in various industries and applications, owing to the growing significance of environmental, social, and governance (ESG) management in corporate operations. In particular, the monitoring of hazardous gas leakages and detection of fugitive emissions have recently garnered significant attention across several industrial sectors. As industrial workplaces evolve to ensure the safety of their working environments and reduce greenhouse gas emissions, the demand for high-performance gas sensors in industrial sectors dealing with toxic substances is on the rise. However, conventional gas-sensing systems have limitations in monitoring fugitive gas leakages at both critical and subcritical concentrations in complex environments. To overcome these difficulties, recent studies in the field of gas sensors have employed techniques such as mobile robotic olfaction, remote optical sensing, chemical grid sensing, and remote acoustic sensing. This review highlights the significant progress made in various technologies that have enabled accurate and real-time mapping of gas distribution and localization of hazardous gas sources. These recent advancements in gas-sensing technology have shed light on the future role of gas-detection systems in industrial safety.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.4
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• pp.479-485
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• 1996

Volatile organic compounds are air pollutants exhausting from industrial process, evaporation of solvent, and so on. Most of VOCs are the combustible gas of low calorific value as it is diluted by air. The systems burning such a hazardous gas need to increase enthalpy in order to increase flame stability. In this study an incinerator with reciprocating flow in the honeycomb ceramic has been used for the experiment of VOCs control. By the reciprocating flow system, the enthalpy of combustion gas is effectively regenerated into the enthalpy increases of the combustible gas through the honeycomb ceramic, which provides a heat storage. The position of the reaction zone is strongly dependent on the parameters of mixture velocity and time frequency. Flame front is changed to the point where burning velocity is coincided with burning velocity in the honeycomb ceramic. In this system it is important that flame front should be located symmetrically at the center of honeycomb ceramic for the purpose of increasing the reaction rate at one point. Peak temperature becomes higher with decreasing time frequency, at which the flow direction is regularly reversed.

• Analytical Science and Technology
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• v.33 no.1
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• pp.49-57
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• 2020

Controlling the quality of indoor air is important in order to maintain a healthy life. In this study, we investigated the correlation between the hazardous substance concentration of indoor air and circulation based on different ventilation methods in the apartment, which is one of the representative housing types in Korea. As target substances, we considered the hazardous substances which are generated during the cooking process and radon gas which is originated from building materials. We measured the concentrations of carbon dioxide and fine particles in relation to type of food and ventilation methods in order to determine the change in the concentration levels of hazardous substances which are generated during the cooking process. On the other hand, we measured the concentration of radon gas before and after letting fresh air into a room through windows in order to determine the change in the concentration level of radon gas which is originated from building materials. The results show that turning on the ventilation fan plays a major role in reducing the concentration levels of hazardous substances in the kitchen, and that it is more effective to turn on the ventilation fan during cooking than after cooking to prevent the diffusion of hazardous materials produced by cooking through the indoor air. Also, the results indicate that letting fresh air into a room through windows more than one time a day is necessary to reduce the concentration level of radon gas in the room to safe concentration range.

• Safety and Health at Work
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• v.12 no.3
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• pp.416-420
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• 2021

Hazardous area classification design is required to reduce the explosion risk in process plants. Among the international design guidelines, only IEC 60079-10-1 proposes a new type of zone, namely zone 2 NE, to prevent explosion hazards. We studied how to meet the zone 2 NE grade for a facility handling hydrogen gas, which is considered as most dangerous among explosive gases. Zone 2 NE can be achieved considering the grade of release, as well as the availability and effectiveness of ventilation, which are factors indicative of the facility condition and its surroundings. In the present study, we demonstrate that zone 2 NE can be achieved when the degree of ventilation is high by accessing temperature, pressure, and size of leak hole. The release characteristic can be derived by substituting the process condition of the hydrogen gas facility. The equations are summarized considering relation of the operating temperature, operating pressure, and size of leak hole. Through this relationship, the non-hazardous condition can be realized from the perspective of inherent safety by the combination of each parameter before the initial design of the hydrogen gas facility.

• Journal of the Korean Institute of Gas
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• v.13 no.3
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• pp.7-14
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• 2009

Many countries are managing the transportation of hazardous materials under the specific provisions especially, as well as use, storage and management, because of their high risks. For the purpose of the revision of rail safety law for the safe transportation of hazardous materials, amount and kind of hazardous materials transported by rail in Korea are analysed and the standards of classification of hazardous materials are compared in domestic and abroad. There are lots of benefits for national rail safety law to implement an international law because our country's geographic location is convenient to connect the continent and to across the border. It is suggested that implementing a classification and test methods of hazardous materials enable to use internationally for the preparation of rail transportation to be increased.

• Journal of Drive and Control
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• v.19 no.2
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• pp.27-35
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• 2022

This study presents one man-portable, hazardous gas detecting and capturing robot. The robot can be fit in the trunk of a sedan car. Its weight is less than 20 kg. A dedicated gas intake mechanism is proposed for the robot. The robot can detect and capture gases at a height of 2 m above the ground, although the height of the robot is about 0.2 m. The performance of the gas intake mechanism is verified through computational fluid dynamics (CFD) analysis and experiments. Its gas detecting signals were acquired by serial communication and processed in Robot Operating System (ROS) based control software. The proposed robot can successfully move on rough terrains such as stairs, sand roads, and rock roads.

• Journal of the Korean Institute of Gas
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• v.28 no.1
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• pp.19-26
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• 2024

In workplaces handling flammable gas such as hydrogen, hazardous area is determined through KS C IEC 60079-10-1 standard. Because this standard determines the hazardous distance based on the release characteristic regardless of the type of gas, indoor/outdoor conditions, and atmospheric conditions, concerns are being raised about the effectiveness. In this study, simulations (PHAST, HyRAM) were performed to calculate the hazardous distance for hydrogen under various release characteristics and atmospheric conditions, and compared these results to IEC standard log-log graph. Also, we performed regression analysis according to each result. we found that the simulation results were 0.6 to 3.8 times less than the IEC standard, presented convenient linear regression equations. In addition, We confirmed that the results of hazardous distance varied based on wind velocity and atmospheric stability at the same release characteristic. In addition, we derived linear regression equations for release characteristics and hazardous distance that can be conveniently utilized. So, when classifying hazardous area in workplaces where they handle the hydrogen, the integrated graph and linear regression equation are helpful for confirming the hazardous area. Moreover, it is expected that the economic burden will be minimized by being able to classify reasonable hazardous area and to greatly reduce the risk of hydrogen explosion.

• Journal of international Conference on Electrical Machines and Systems
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• v.1 no.1
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• pp.128-134
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• 2012

This paper gives an overview of the requirements for electrical equipment in potentially explosive atmospheres and describes how these are applied to electrical machines and drives in hazardous areas. The method by which equipment can be shown to be safe in a whole range of gases, by testing in a single test gas, is covered. It is shown how the more recently introduced methods of protection for hazardous areas, increased safety and nonsparking, are ideally suited to AC machines and drives. A novel method of measuring the fullload temperature rise of electrical machines for hazardous, and other areas, without the need to connect a mechanical load to the machine's drive shaft is explained.