• The Journal of the Convergence on Culture Technology
• /
• v.5 no.3
• /
• pp.43-54
• /
• 2019

In this study, results of completion inspection are investigated according to the performance of the firefighting construction supervision personnel and according to the necessity of clean air supply in a performance test of the firefighting construction supervision personnel. The results of the completion inspection are measured and the causes of defects in the fire protection facilities after issuance of a completion inspection certificate are analyzed. The findings of this investigation can be used to minimize the risk of apartment fires and improve the performance of firefighting construction supervision personnel. The results of this study are summarized as follows. First, the results of the completion inspection conducted by the firefighting construction supervision personnel varies according to particular occupation. The performance of fire facility supervisors from design companies and fire construction companies were significantly higher than the fire officers. Therefore, it is necessary to employ supervisors who have experience in supervising the construction of apartments, in order to improve the performance of fire construction supervision officers. Second, the analysis of the completion inspection results according to the necessity of a clean air supply for performance tests of firefighting construction supervision personnel showed that the necessity of a clean air supply was significantly higher for fire facility supervisors from design companies and fire construction companies than for the fire officers. In order to improve, the completion inspection should be carried out up until the completion date of the building. In addition, a system needs to be established to ensure that clients are not able to demand that a completion inspection certificate be issued on the construction completion date. Finally, it is found that defects of completion inspection after issuance of a completion inspection certificate affects the result of the completion inspection. The results of the completion inspections conducted by the fire facility supervisors from design companies and fire construction companies were affected significantly less by defects than that of the general contractors. Research shows that faults have occured in firefighting facilities after the issuance of a completion inspection certificate due to the client and the construction company demanding the issuance of the completion inspection certificate.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.2
• /
• pp.325-333
• /
• 2015

In this paper, we are aim to analysis the effects of optical cable fault on customer complaints. We considered several causes: the elapse time to allow repair from the optical cable fault, whether working day or not, seasonality and human error, external construction, optical cable cutting or core banding that is controllable causes and natural disasters, vehicle crash, fire that is uncontrollable causes. The results of analysis are as follows: First, customer complaints increase through indifferencial relationship when using the production function for the number of expected victims and elapsed time due to the optical cable fault. Second, not only the elapsed time but also controllable variables, human error, external construction, the core cut occurs, increased customer complaints due to optical cable faults.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2008.11a
• /
• pp.918-921
• /
• 2008

There are various accident at the Construction site like fall, electric shock, roll over, clash, fire, body cutting. By the way, falls are the most causes accidents. So, the best way of decreasing Construction accidents is decreasing falls. Already, there are many studies about falls accidents, but those studies were pointed out unrealistic because falls accidents are increasing. For that reason, this study look for more concrete device. In this study, grasp the cause of falls accident from 2007 to 2008. 06. 30. And then, stand on this factor I set my face to look for the causes of falls accident. This access means will drive to remove core causes, and then that means will decrease the falls accidents. Moreover that means will contribute decreasing the hole construction accidents.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.4
• /
• pp.568-574
• /
• 2020

Recently, the installation of energy storage systems (ESSs) that have a range of functions, such as power stabilization of renewable energy sources, demand control, and frequency regulation, has been increasing annually. On the other hand, since the fire accident of ESS occurred at Gochang Power Test Center in August 2017, 29 fire accidents with significant property losses have occurred, including the Gyeongsan substation and Kunsan PV power plant. Because these fire accidents of ESS are arisen regardless of the season and capacity of ESS, an analysis of the fault characteristics in ESS is required to confirm the causes of the fire accidents accurately and ensure the safety of the ESS. This paper proposes the modeling of ESS using PSCAD/EMTDC S/W to identify the fault characteristics and ensure the safety of the ESS. From the simulation results of fault characteristics based on various scenarios, it is clear that the insulation of ESS may be breakdown due to the largely occurring CMV (common mode voltage). Furthermore, the CMV between the PCS and battery can be reduced, and the insulation breakdown of ESS can be prevented if an SPD (surge protect device) is installed in the battery and PCS sides, respectively.

• Fire Science and Engineering
• /
• v.32 no.2
• /
• pp.57-66
• /
• 2018

The most urgent requirement in the event of disaster and fire in a skyscraper is to establish a system that enables people inside to evacuate safely. Hence, a practical direction needs to give evacuees confidence in the evacuation by reducing the psychological anxiety caused by the relatively large number of people inside and at the same time, the physically prolonged evacuation travel line. Evacuation tests with large numbers of people were conducted three times to solve these challenges and identify phenomena and issues that occurred during the experiment. The results revealed the factors that could cause a delay in evacuation and suggested improvements. The study results of this paper are as follows. First, a recent fire at a multipurpose high-rise resulted in a number of casualties due to a lack of experience with the disaster prevention system. To prevent such cases from occurring in advance, adaptability was achieved by conducting evacuation tests. Second, the data collected in the evacuation simulation statistics and the actual escape drills were compared and analyzed. Third, in the evacuation experiment, a large number of people could not participate in the experiment. The reasons for not participating were analyzed and their impact on the actual evacuation time was confirmed. Fourth, equipment aids were purchased to establish the optimal response measure to the causes of a delay in escape time and the standards for ensuring the safety of the evacuee were specified by developing improvements to minimize the evacuation delay time through comparative before and after analysis of the experiment. These results can be used for fire safety control of skyscrapers to improve the efficiency of evacuation.

• Journal of the Society of Disaster Information
• /
• v.18 no.3
• /
• pp.574-580
• /
• 2022

Purpose: As corn oil is semi-drying oil, it has more double bonds than non-drying oil and is easier to combine with oxygen. In addition, among the causes of spontaneous ignition, accidents caused by oil-soaked cloths due to oxidative heat are gradually increasing. Therefore, the purpose of this study is to understand the characteristics of spontaneous combustion according to the number of towels and the amount of corn oil at 65℃. Method: After setting the test temperature to 65℃, 25ml, 50ml, 75ml of corn oil per towel was sprayed. The central temperature of the sample rises above the set temperature. It was determined, and when the central temperature of the sample became similar to the set temperature, it was determined as non-igniting. Result: After evenly distributing 25ml of corn oil per towel, as a result of the experiment, 5 towels did not ignite, and 10 and 15 towels ignited. Also, as a result of an experiment using 50ml and 75ml of corn oil per towel, spontaneous ignition occurred when the number of towels was 5, 10, or 15 sheets. Conclusion: Even a small amount can cause a fire if the conditions for spontaneous ignition are met.

• Fire Science and Engineering
• /
• v.19 no.1 s.57
• /
• pp.80-86
• /
• 2005

In this study effects of the natural wind and the forced smoke ejection by operating the exhaust fan are studied numerically to examine the flow characteristics of the smoke and heat generated from a fire on the platform of an underground subway station. Three different situations, including 1) the case with no natural wind and no exhaust fan operation, 2) the case with natural wind but no exhaust fan operation and 3) the case with no natural wind but exhaust fan operation, are considered for the numerical analyses. The numerical results show that the natural wind causes a rapid spread of the fire along the tunnel resulting in rapid spread of the smoke and heat over the platform which affects the escape. The operation of the exhaust fan also results in the rapid spread of smoke and heat over the platform, but the time required for reaching the safe escaping height of the smoke layer with the exhaust fan operation is much longer than that without the exhaust fan operation. The numerical results also show that the required capacity of the exhaust fan becomes larger when the effect of the natural wind is included.

• Fire Science and Engineering
• /
• v.23 no.3
• /
• pp.40-47
• /
• 2009

Nowadays the diversity and large-capacity of electric appliances are strong effect on electrical fires augment in an alarming way. But, as the inactive response characteristics of the existing RCD (Residual Current protective Device) used on low voltage power distribution system, so control of overload and electric short circuit faults, major causes of electrical fires, are not enough. Therefore, this paper is confirmed the unreliability of the existing RCD by electrical fault simulator and is proposed a Electrical Fire Disaster Prevention Device (EFDPD) by using a high precision current sensor (namely, reed switch) for the prevention of electrical disasters in low voltage power distribution system caused by overload or electric short circuit faults. The sensitive reed switch in the proposed EFDPD exactly detects the increased magnetic flux with the overload or the short current caused by a number of electrical faults, and the following, the EFDPD has double protection function which operates self circuit breaker or rapidly cuts off the existing RCD. The proposed EFDPD is confirmed the excellent characteristics in response velocity and accuracy in comparison with the conventional circuit breaker through various operation performance analysis. The proposed EFDPD can also prevent electrical disaster, like as electrical fires, which resulted from the malfunction and inactive response characteristics of the existing RCD.

• Fire Science and Engineering
• /
• v.25 no.6
• /
• pp.136-145
• /
• 2011

One of a large proportion among the causes of fire is electrical factors, and of fire by electric factors, the accident which accounted for over certain percentage is electric leakage and ground fault. In order to reduce the electric leakage and ground fault, the technical guidelines on the protection of ground fault in the low-voltage electrical line (KECG 1091-2011) was amended for reflecting recent international standard, IEC 60364-4-41, and new conservation methods, which improved the reliability by recovering the facility's all-time use operation and breakdown defect, was on the rise. Accordingly, in this paper, after grasping the fire's status for last 10 years and analyzing the risk of electrical fires, and as a way to improve the electric leakage and ground fault accident which accounted for more than certain percentage, the revision of KECG 1091-2011 will be reviewed. And then, after applying to the preventive conservation methods in order to enhance the protection reliability of electric leakage and ground fault detection, the problems at issue routine inspection scheme and durable years scheme in time-scheduled conservation method are listed, along with suggestion of the problem-solving scheme, and the leakage current integrated monitoring systems and digital electric leakage devices by status monitor conservation method will be proposed.

• Journal of the Ergonomics Society of Korea
• /
• v.30 no.1
• /
• pp.87-98
• /
• 2011

In this study, we investigated and identified criterial human factors(errors), most of which lead to terrible ship accidents such as collisions, sinking, fire and explosions resulting both in human lives and physical damages to ships as well as surrounding environments. To this end, we went through the accident reports of 413 cases over 2005~2009 period and classified the human factors into 6 major factors with 19 sub ones which were constructed in hierarchical order. The relative importance of major factors was calculated and among others the lack of awareness turned out to be the most important factor with the weight of 0.391. The contributions of the results in the research are two fold: it will help (i) identify the root causes of ship accidents and prevent further potential ship related incidents, (ii) analyze the degree of the risk associated with the ship accidents, when risk analysis is performed.