• Journal of the Korean Society of Safety
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• v.19 no.1
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• pp.49-55
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• 2004

This study presents an analysis of comparison of P-type fire detection system with fuzzy logic-applied fire detection system. The fuzzy logic-applied fire detection system has input variables obtained by fire experiment of small scale with K-type temperature sensor and optical smoke sensor. And the antecedent part of fuzzy rules consists of temperature and smoke density, and the consequent part consists of fire probability. Also triangular fuzzy membership function is used for input variables and fuzzy rules. To calculate the final fire probability a centroid method is introduced. A fire experiment is conducted with controlling wood crib layer, cigarette to simulate actual fire and false alarm situation. The results show that peak fire probability is 25[%] for non-fire and is more than 80[%] for fire situation, respectively. The fuzzy logic-applied fire detection system suggested here is able to distinguish fire situation and non-fire situation very precisely.

• Journal of the Korea Safety Management & Science
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• v.2 no.2
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• pp.41-55
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• 2000

The main objective of this paper is to propose a measure of evaluation for non-normal process capability. If a process is not normally distributed, but normal-based techniques are used, serious errors can result. Our approach to solve this problem is that the Pearson system, the Johnson system, and the Burr system are selected for estimating a measure of process capability using the percentage nonconforming. In this paper, we found that the Pearson system and the Johnson system were a conparatively reasonable methods to calculate out of specification by example.

• Journal of Food Hygiene and Safety
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• v.14 no.1
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• pp.104-114
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• 1999

This study was conducted to find out the proper ways of implementation of Hazard Analysis Critical Control Point (HACCP) concepts applicable to the current Korean food inspection system. The following recommendations are based on an in-depth review of the Canadian Food Safety Enhancement Program (FSEP), which is one of the leading HACCP programs adapted to the food industry. Since 1997, the HACCP system has been voluntarily applied to meat processing plants in Korea in accordance with the Food Protection Law. But the guidelines are obscure and inadequate to expand to the diversity of food plants, and are therefore only applied to a limited number of plants of small scale enterprise. For these reasons, it is necessary to prepare an enhanced food safety control program focused not only on the HACCP plants but also on the non-HACCP plants. The national program should be the fundamental framework of a food safety control policy enforced by all the relevant authorities. The Prerequiste Program of Canadian Food Inspection Agency and Sanitation Standard Operating Procedures (SSOP) of FSIS are good example programs for the non-HACCP plants. These programs, which are a major part of the HACCP system, could easily be adapted to the Korean food industry. To improve the current HACCP implementation guideline, it is necessary to develop a detailed implementation manual, generic HACCP model, training program, and an audit program.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.3
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• pp.265-272
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• 2023

Objectives: Since the material safety data sheets(MSDS) submission and non-disclosure review system was introduced in January 2021, the implementation status of MSDS for chemical manufacturing and importing workplaces being supervised for the first time. Methods: A supervisory team consisting of two labor inspectors and one from the Korea Occupational Safety and Health Agency directly visited the selected workplaces to check compliance with the MSDS system as a whole. Results: As a result of supervising 214 chemical substance manufacturing/importing workplaces, a total of 241 violations of the law were found in 121 workplaces, or 57% of them. In response, the Ministry of Employment and Labor took legal action on 8 cases in 6 locations, imposed a fines totaling of 249.69 million won on 120 chemical handling workplaces, and took action to correct the violations immediately. Conclusions: Major violations were in the order of non-request for warning signs, non-submission of MSDS, non-execution of MSDS training, and non-posting of MSDS. This shows the reality that employers who handle chemical substances are sufficiently communicating chemical information to workers. In the future, the government will actively implement preparation and submission support and system guidance for the implementation of the MSDS system, while making efforts to ensure that the MSDS system works well in the field through thorough on-site supervision in the future.

• Journal of the Korean Society of Safety
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• v.35 no.5
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• pp.22-29
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• 2020

In this study, combustion and smoke release characteristics of a non-class 1E cable for nuclear power plants were investigated according to aging period. The aging was reproduced through an accelerated aging method for interval of 10 years :10, 20, 30 and 40 year, which was applied the Arrhenius equation. The cable was subjected to accelerated aging. In order to understand combustion and smoke release characteristics, the cone calorimeter test was performed according to the standard code of KS F ISO 5660-1. Heat release rate, mass loss rate, average rate of heat emission and smoke production rate were examined through cone calorimeter test. Fire performance index, fire growth index and smoke factor were derived from test results for the comparison of quantitative fire risk. When comparing the fire performance index and the fire growth index, the early fire risk tends to decrease as aging progresses, which might be attributed from the fact that the volatile substances of cables were evaporated. However, when comparing the heat release rate, average rate of heat emission and mass loss rate, which represent the mid and late periods of the fire risk, the values of accelerated aging cables were much higher than those of non-aged cable, which signifies the unstable formation of the char layer resulted in the change in the performance of flame retardants. In addition, the results from the smoke characteristics show that the accelerated aging cables were lager than the non-aged cables in terms of overall fire risk. These results can be used as baseline data when assessing fire risk of cables and establishing fire safety code for nuclear power plants.

• Safety and Health at Work
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• v.2 no.1
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• pp.52-56
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• 2011

Objectives: The occupational accident rate was officially reported to be 0.77 per 100 workers in 2001 and 0.70 in 2009. The stagnant decrease in accident rate raises a question about the effectiveness of prevention activity because there have been active prevention efforts in the past 10 years. It is also necessary to know the exact status of occupational injuries to direct a prevention strategy. Methods: The author re-analyzed occupational injury statistics to find the reason for stagnant decreases in occupational injuries. Compensated occupational injuries cases were used to calculate fatal and non-fatal injury rates. Injuries from commuting accidents and sports activities were excluded as well as occupational diseases. The number of workers was adjusted to that of full time equivalent employees. Results: The fatal injury rate excluding injuries associated with commuting accidents, sports activities, and occupational diseases decreased from 12.59 in 2001 to 8.20 in 2009. In 2007, 67.5% of accidents that involved being caught in objects, which are mostly caused by machines and equipment, occurred in the manufacturing industry; this type of incident has decreased since 2001. The fatal and non-fatal injury rates in the manufacturing industry have continuously decreased while the rates in the service industry have not changed from 2001 to 2009. Non-fatal injuries might not be reported in many cases. The number of insured workers was underestimated as long working hours were not adjusted for in the reporting system. Conclusion: The occupational fatal injury rate has decreased and the non-fatal injury rate might have decreased during the last 10 years, although the statistics show stagnancy. The decrease of the injury rate was countervailed by various factors. Hence, the current accident rate does not reflect the actual situation of accidents in Korea. Korea needs to develop an improved system to more accurately calculate occupational fatal and non-fatal injury rates.

• The Korean Journal of Air & Space Law and Policy
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• v.33 no.1
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• pp.81-120
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• 2018

To promote the aviation safety reporting system that is operated to enhance aviation safety and to utilize related information, it should first be preceded by standards for non-punishment and data protection. It is because the purpose of collection and analysis of aviation safety related data through the aviation safety reporting system is to prevent recurrence of accidents by investigating their causes through collection and analysis of diverse types of information related to aviation safety. Both mandatory and voluntary reporting systems are in operation for aviation safety under the current Aviation Safety Act. It is said that they were introduced to survey causes for accidents and to prevent recurrences. In fact, however, it is hard to expect active implementation of the reporting system for aviation safety unless the reporters are firstly exempted from punishment. Therefore, the system should be improved so that it can satisfy its purpose and the purposes of data collection concerning aviation safety through examination of the purposes of the reporting system. One of the matters that needs to be considered to promote the reporting system should be the scope of aviation safety hindrances presupposed under the current institution. The voluntary aviation safety reporting system differs from the systems of ICAO or the key advanced countries, including the USA and the UK as it limits the target accidents subject to reporting to minor aviation safety hindrances only. That being said, improvements should be made by requiring mandatory reporting of aviation safety hindrances based on their severity while recognizing a greater variety of aviation safety concerns like international standards. Safety actions and sharing of information based on collection and analysis of diverse data related to aviation safety will greatly contribute to enhance aviation safety as the purposes of the reporting system are to explore causes for accidents and to prevent their recurrences. What is most important in this regard is strict data protection and non-punishment principles; compliance with them should be secured. We can hardly expect the successful operation of the system unless the reporter is exempted from punishment and the relevant data is protected as promotion of voluntary reporting is an essential factor for enhancing the safety culture. Otherwise, the current system may induce hiding of relevant facts or data to evade punishment. It is true that the regulation for enhancing safety tends to have limitations or blind spots; nevertheless, it should still be enforced strictly and completely. Technological progresses and mistakes of operators appear in different forms based on individual cases. The consequential damages may amount to a truly severe level. Therefore, we have studied and suggested to the methods of activiation and amendments on the aviation safety reporting system, which is referred for one of the proactive safety management systems. The proposed improvement of the reporting system and introduction of non-punishment for collection of aviation safety data for deploying a preemptive prevention system would serve as the backbone for enhancing aviation safety in Korea.

• Journal of the Korea Safety Management & Science
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• v.3 no.3
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• pp.175-190
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• 2001

We propose, a new process capability index $C_{psk}$(WV) applying the weighted variance control charting method for non-normally distributed. The main idea of the weighted variance method(WVM) is to divide a skewed or asymmetric distribution into two normal distributions from its mean to create two new distributions which have the same mean but different standard deviations. In this paper we propose an example, a distributions generated from the Johnson family of distributions, to demonstrate how the weighted variance-based process capability indices perform in comparison with another two non-normal methods, namely the Clements and the Wright methods. This example shows that the weighted valiance-based indices are more consistent than the other two methods in terms of sensitivity to departure to the process mean/median from the target value for non-normal processes. Second method show using the percentage nonconforming by the Pearson, Johnson and Burr systems. This example shows a little difference between the Pearson system and Burr system, but Johnson system underestimated than the two systems for process capability.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.3
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• pp.365-374
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• 2023

Objectives: After the MSDS submission and non-disclosure review system was introduced in January 2021, there were compliance difficulties in the field. Accordingly, for the establishment of the MSDS system, the government intends to investigate what has been improved and what urgently needs to be improved in the future, and to suggest detailed improvement plans. Methods: The background and problems of urgent difficulties in the field handling chemicals were investigated, and realistic improvement plans were derived through review of other laws related to the MSDS system and overseas cases. Results: In order to guarantee the safety of the public while at the same time promoting corporate R&D, it is necessary to alleviate the non-disclosure screening system for chemical substances for R&D, and to improve the irrationality of failing to implement the non-disclosure screening system due to information on unclassified substances being circulated. For this reason, it seems necessary to ease the requirement to submit all ingredients. In addition, it is necessary to strengthen punishment to raise awareness so that health problems do not occur due to the harmfulness and danger of hidden substances among workers who handle chemical substances and downstream users due to false descriptions in MSDS. Conclusions: All members of our society, including chemical manufacturers/importers and handling companies, academia, civil society, and the government, each subject of chemicals, should take an interest in the entire process from production to disposal of chemicals and work together to prevent harm to the public.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.12
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• pp.1637-1639
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• 2014

In the past, the analog protection relays have been widely used for the safety-related systems in the nuclear power plants due to their stability and reliability. Meanwhile, as the high performance digital system has been developed, the digital systems have been adopted in the non-safety systems. However, since the digital systems currently used in the non-safety systems were not developed according to Q-class standard, Commercial Grade Item Dedication (CGID) procedure should be performed in order to apply them to the safety-related system. The purpose of this paper is to describe the CGID procedure including the analysis of the hardware architecture as well as the software embedded in protective relay to apply to the emergency diesel generator in the nuclear power plant. The entire CGID procedure was performed strictly according to the international standard and regulations.