• Journal of the Korean Society of Industry Convergence
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• v.23 no.5
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• pp.865-874
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• 2020

Offshore drilling units have a very dangerous working conditions due to the harsh working environment of the ocean and the high possibility of fire or explosion. This study would identify the hazards that emerge from the marine environment in the operation and maintenance phase of offshore drilling units and show how these hazards can be reduced through risk assessment/management. Various risk reduction and management measures were first reviewed, and Job Safety Analysis (JSA) was selected as the risk assessment technique of this study. In order to understand the characteristics of offshore drilling operations, accident statistics of onshore and offshore drilling were analyzed and compared with each other, and major risk factors for offshore drilling were derived. The jobs in which offshore drilling accidents occur more frequently than onshore drilling was analyzed as the job of fastening, transporting and moving pipes and various materials. This result is due to the limited space of the ocean and the work environment that is prone to being shaken by wind, waves and ocean currents. Based on these statistical results, the job of picking and making up drill pipes was selected as a high-risk job, and JSA was performed as an example. A detailed safety check procedure is proposed so that workers can fully recognize the danger and perform work in a safe state that has been confirmed.

• Korean Chemical Engineering Research
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• v.55 no.5
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• pp.629-637
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• 2017

Severe dust explosions occurred frequently in food processing industries and explosion damage increase by flame propagation in pipes or plants. However there are few fire explosion data available due to various powder characteristics. We investigated the characteristics of ignition and explosion on sugar, cornstarch and flour dust with high frequency accidents and high social demand. The measurements showed the median diameter of 27.56, 14.76, $138.5{\mu}m$ and ignition temperature has been investigated using by thermo-gravimetric analysis (TGA) and differential scanning calorimeter (DSC). The maximum explosion pressure ($P_m$) and dust explosion index ($K_{st}$) of sugar, cornstarch and flour are 7.6, 7.6, 6.1 bar and 153, 133, 61 [$m{\cdot}bar/s$], respectively. The flame propagation time in duct was calculated in order to evaluate the damage increase due to flame propagation during dust explosion. The explosion hazard increase due to flame propagation was higher in the order of sugar, flour and cornstarch dust.

• Journal of the Society of Disaster Information
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• v.13 no.1
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• pp.15-25
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• 2017

Since the late 19th century, the annual average temperature of the Earth has risen due to excessive emission of greenhouse gases, and abnormal weather phenomena such as heavy rain and heavy snowfall have been increasing frequently all over the world. In a city with high population growth due to high economic growth, fire and terrorist accidents can cause serious property damage and human casualties. The purpose of this study is to propose the need for evacuated facilities to protect victims, and suggest adequate shelters' size which can be protectable them. In spite of the Ministry of Public Safety and Security designated 3.3 square meters of per capita capacity, they does not specify the basis about setting this criterion.

• Journal of the Korean Institute of Gas
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• v.21 no.4
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• pp.30-41
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• 2017

Although chemical substances have greatly contributed to prosperous human life and industrial development and made a great contribution to humanity, some dangerous substances are harmful to health and the environment. Thus, so long ago developed countries have also established strict safety standards. Korea is growing into a major chemical market, accounting for 3.4% of the global chemical market. The domestic laws related to chemical substances are similar to foreign countries, but there are many differences in detail, posing a lot of risks to safety, health and the environment as well as causing many problems in industry. In order to improve these problems, this study carried out to unify the domestic chemical law and the international standardization system (GHS) and to solve the trade barriers in the export and import by industry. In addition, researchers proposed a unified approach to classification and division of physical hazards, as advanced as developed nations, as a basis for prevention and response to accidents in dangerous goods.

• Korean Chemical Engineering Research
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• v.52 no.6
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• pp.750-754
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• 2014

Quantitative risk analysis has been performed for a pervaporation process for production of high test peroxide. Potential main accidents are explosion and fire caused by a decomposition reaction. As the target process has a laboratory scale, the consequence is considered to belong to Category 3. An event tree has been developed as a model for occurrence of a decomposition reaction in the target process. The probability functions of the accident causes have been established based on the frequency data of similar events. Using the constructed model, the failure rate has been calculated. The result indicates that additional safety devices are required in order to achieve an acceptable risk level, i.e. an accident frequency less than $10^{-4}/yr$. Therefore, a layer of protection analysis has been applied. As a result, it is suggested to introduce inherently safer design to avoid catalytic reaction, a safety instrumented function to prevent overheating, and a relief system that prevents explosion even if a decomposition reaction occurs. The proposed method is expected to contribute to developing safety management systems for various chemical processes including concentration of hydrogen peroxide.

• Korean Journal of Human Ecology
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• v.19 no.1
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• pp.215-225
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• 2010

This study had the purpose of presenting a residential environment solution as a desirable educational environment for middle school students to grow soundly and to achieve proper self-realization while providing basic materials to build up a suitable residential environment by comparing and analyzing what relationships exist between different home backgrounds, residential environments and middle school students' social maturity. This research was conducted from Feb. 11, 2008 to Feb. 13, 2008. The subject of this research was 601 students in 3 middle schools located in Gyunggi-do. The data analyzed used the SPSS 11.5 version. The summary of this study's results is as follows. First, in terms of home background, the higher the parents' educational background and social and economic position, the greater the students' social maturity. Second, in terms of home environment, the more spacious the living space, the better the water and sewage system and rest room, the more convenient the air conditioner and kitchen system, the better the lighting, ventilation, soundproofness, insulation, the less the danger in relation to fire, crime, traffic accidents, disaster, the greater the students' social maturity. Third, in terms of the home environment related to the correlation between the residential environment and social maturity, all areas such as housing facilities, housing structural environment and housing safety showed static correlations and proved that the residential environment has an important influence on social maturity. Accordingly, in order to build up an ideal residential environment, we should make efforts to expand and improve better facilities at home considering privacy, lighting, ventilation, soundproofness, heating etc. and remove unsound factors that obstruct students social maturity and build up clean and safe residential environment with good relations with their neighbors.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.2
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• pp.177-184
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• 2017

Many ground subsidence accidents have happened in Korea. The accident was caused by the subsidence and leakage of the deteriorated sewage pipe. This study aims to establish the empirical data of the ground penetration radar(GPR) detection for ground subsidence. A test bed was also manufactured for the same purpose. The GPR detection variables are embedment depth and horizontal distance of embedded cast iron pipe and expanded polystyrene(EPS). From the detection results, the EPS embedded by a depth of 1.5m was difficult for detection. The EPS closely embedded to the cast iron pipe within a 0.5m distance had a very strong cast iron pipe signal. Therefore, the detection was impossible. This study developed an image processing program, called the GPR image processing program(GPRiPP), to process the GPR detection results. Its major function is the gain function, which amplifies the wiggle wave signal. Compared to the existing programs, the GPRiPP is capable of showing a similar image processing performance.

• Journal of Hydrogen and New Energy
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• v.25 no.6
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• pp.609-619
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• 2014

In the present study, the frequency of the undesired accident was estimated for a quantitative risk assessment of a large-scale hydrogen liquefaction plant. As a representative example, the hydrogen liquefaction plant located in Ingolstadt, Germany was chosen. From the analysis of the liquefaction process and operating conditions, it was found that a $LH_2$ storage tank was one of the most dangerous facilities. Based on the accident scenarios, frequencies of possible accidents were quantitatively evaluated by using both fault tree analysis and event tree analysis. The overall expected frequency of the loss containment of hydrogen from the $LH_2$ storage tank was $6.83{\times}10^{-1}$times/yr (once per 1.5 years). It showed that only 0.1% of the hydrogen release from the $LH_2$ storage tank occurred instantaneously. Also, the incident outcome frequencies were calculated by multiplying the expected frequencies with the conditional probabilities resulting from the event tree diagram for hydrogen release. The results showed that most of the incident outcomes were dominated by fire, which was 71.8% of the entire accident outcome. The rest of the accident (about 27.7%) might have no effect to the population.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.18 no.1
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• pp.58-63
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• 2010

Introduction : Head trauma is the main cause of death in aircraft crash. In a Michigan study of structurally survivable, fatal accidents, 80% of the fatally injured had received head trauma. We tried to develop a new helmet for passengers, and perform its efficiency test. Methods : An aircraft helmet requires an excellent protection against head trauma, lightness, and small volumes. In addition, it must be wearable, fire resistant, and non toxic when it is burning. We developed two new helmets made from silicone foam which met all theses requirements. One was thin (2.5cm), and the other was thick (6.3cm). These looked like a motorcycle helmet and had only a soft silicone as liner material without an outer hard shell. Therefore we can carry them easily inside aircrafts. The standard test for helmet is Snell's drop test. It measures the impact acceleration of head shaped metal wearing helmet during we drop it at certain heights. Impact sites were total 5 sites (front, back, right, left and top) for each helmet. All these sites were impacted twice. Results : The thickness of impact sites varied from 2.5cm to 6.3cm. The impact acceleration of 2.5cm thickness site when it was dropped from 1.0 meter was 379g. But, that of 6.3cm thickness site when it was dropped from 1.5 meter was only 163g. Unfortunately, both helmets didn't meet the Snell Standard for motorcycle helmets. Discussion : If we add suitable outer hard shell, and change its thickness and design, the efficiency will be increased. A study indicated that helmet could reduce the risk of head trauma up to 85%. We made helmet for passengers in aircraft crash for the first time. If we improve its weak points, it will decrease the frequency of head trauma in aircraft craft.

• Journal of Acupuncture Research
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• v.28 no.2
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• pp.49-55
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• 2011

Objectives : This study was to develop programmable and rechargeable electronic moxibustion device as an interdisciplinary research focusing on traditional Korean medicine. Methods : This device deployed several advances on safety and conveniences with the advantage of programmable heat stimulation, heating material and recharging method. The gradient of heat stimulation was programmed with the reference of previous studies and own measurements. The heat curve reached its efficacious stimulus temperature after three minutes, and maintained until 13 minutes with $42^{\circ}C$. We also incorporated feedback from field hospital experiences with the help of hospital staffs. Results : This device can prevent damages from skin burn and fire accidents, and control the smoke, smell and residue of moxa itself. Conclusions : This study will contribute for the development and improvement of efficacious and safe treatment methods for the traditional Korean medicine.