• Journal of Radiation Industry
• /
• v.12 no.4
• /
• pp.303-310
• /
• 2018

Since Roentgen discovered X-rays, radiation sources have been utilized for many areas such as agriculture, industry, medicine and fundamental chemical research. As a result, human society has gained lots of benefits. However, if a radioactive material is used for the malicious purpose, it causes serious consequences to humanity and environment. Consequently, international organizations including International Atomic energy Agency (IAEA) have been emphasizing establishment and implementation of security management to prevent sabotage and illicit trafficking of radioactive materials. For this reason, the rule of technical standards of radiation safety management was revised and the public notice of security management regarding radioisotope was legislated in 2015 by Nuclear Safety and Security Commission (NSSC). Several radioactive sources which have to be regulated under the above rule and the public notice have been utilized in Advanced Radiation Technology Institute (ARTI) of Korea Atomic Energy Research Institute (KAERI). In order to control them properly, security management system such as access control and physical protection has been adapted since 2015. In this paper, we have analyzed the public notice of NSSC and its field application case. Based on the results, we are going to draw improvement on the public notice of NSSC and security system.

• Journal of the Korean Society of Radiology
• /
• v.16 no.7
• /
• pp.815-824
• /
• 2022

The current radiation safety management system is also applied to radiation practices at universities. The application of the law raised concerns about poor radiation practice education and hindering the development of radiology. Accordingly, the Korean Radiology Professors Association needed to grasp the reality of the management system for radiation practice education at each university and the current radiation safety management system in the department of Radiological science. So, a survey was conducted on heads of radiological science departments across the country. Through the survey, it was found that the current application of the Nuclear Safety Act to radiation safety management in the department of Radiological science is excessively restrictive and not very effective. In addition, radiology practice education for the purpose of training health and medical professionals should be controlled by the Ministry of Health and Welfare and the Korea Centers for Disease Control, but there is a problem of being supervised by the Nuclear Safety and Security Commission. Therefore, in this study, as a legal improvement plan to solve this problem, first, a plan according to a partial amendment to the Higher Education Act, second, a plan to be supervised by the Ministry of Health and Welfare through the amendment of article 37 of the Medical Service Act, third, article 20-2 of the Enforcement Decree of the Medical Service Technologists Act was newly inserted to propose three measures to be supervised by the Ministry of Health and Welfare.

• Journal of Radiation Protection and Research
• /
• v.33 no.2
• /
• pp.77-86
• /
• 2008

This study attempted to provide reference materials for improving the behavior level in radiation safety managements by drawing a prediction model that affects the radiation safety management behavior because the radiation safety management of medical Cyclotrons, which can be used to produce radioisotopes, is an important factor that protects radiation caused diseases not only for radiological operators but average users. In addition, this study obtained follows results through the investigation applied from January 2 to January 30, 2008 for the radiation safety managers employed in 24 authorized organizations, which have already installed Cyclotrons, through applying a specific form of questionnaire in which the validity was guaranteed by reference study, site investigation, and focus discussion by related experts. The radiation safety management were configured as seven steps: Step 1 is a production preparation step, Step 2 is an RI production step, Step 3 is a synthesis step, Step 4 is a distribution step, Step 5 is a quality control step, Step 6 is a carriage container packing step, and Step 7 is a transportation step. it was recognized that the distribution step was the most exposed as 15 subjects (62.5%), the items of 'the sanction and permission related works' and 'the guarantee of installation facilities and production equipments' were the most difficult as 9 subjects (37.5%), and In the trouble steps in such exposure, the item of 'the synthesis and distribution' steps were 4 times, respectively (30.8%). In the score of the behavior level in radiation safety managements, the minimum and maximum scores were 2.42 and 4.00, respectively, and the average score was $3.46{\pm}0.47$ out of 4. Prosperity and well-being programs in the behavior and job in radiation safety managements (r=0.529) represented a significant correlation statistically. In the drawing of a prediction model based on the factors that affected the behavior in radiation safety managements, general characteristics, organization characteristics, and selfefficacy didn't show a significant path statistically in which the prosperity and well-being programs in job characteristics affected the behavior in radiation safety managements. Therefore, it is necessary to establish a strategy that improves the level of prosperity and well-being levels in job characteristics in order to increase the behavior in radiation safety managements. Thus, this study provides basic materials for the radiation safety management of Cyclotron through the full-scale investigation that is first applied in Korea.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.31 no.4
• /
• pp.342-352
• /
• 2021

Objectives: This study analyzed the local exposure levels of radiation emitted from the equipment with soft X-ray ionizers to investigate the radiation exposure levels in Liquid Crystal Display(LCD) manufacturing processes. Methods: This study measured the local radiation levels for the equipment installed in two LCD manufacturing companies. The equipment were installed at diverse processes and equipped with various number of ionizers. The local radiation levels were measured on the surface of the equipment by using direct reading equipment, and the measurements were converted into annual effective dose by considering the radiation exposure time of workers. Statistical analyses were performed to investigate the radiation exposure characteristics. Results: Annual effective doses for 97.6% of the equipment being measured were less than 1 mSv. However, the range of annual effective doses was 0.004 mSv ~ 2.167 mSv, which indicated a large variation among the equipment. Statistical analyses of the study found that this large variation was raised due to improper shielding of the equipment rather than process and/or equipment characteristics. To pinpoint the cause of this large variation in annual effective dose, this study improved the shielding of the equipment being radiated over 1 mSv and found that their average effective dose was reduced from 1.604 mSv to 0.126 mSv after shielding improvement. Conclusions: Relatively high exposure levels of radiation were observed in some equipment where their shielding were insufficiently thick and/or sealed. This finding implies that the shielding of the equipment is an important engineering countermeasure to control the radiation exposure levels in industries.

• Journal of Institute of Control, Robotics and Systems
• /
• v.10 no.3
• /
• pp.249-254
• /
• 2004

The radiation dosage of nuclear fuel handling machine of PHWR type NPP during normal operation is measured using semiconductor detectors. In order to predict and mitigate the damage of main components in fuel handling machine, caused by high irradiation, the radiation dosage exerted to the components by neutron and gamma ray is measured independently during one time of the fuel exchange, which is used far estimating the radiation dosage for one year. This result can guarantee the safety and economical efficiency for determining the replacement time of the high cost main components in fuel handling machine.

• Journal of Radiation Protection and Research
• /
• v.44 no.2
• /
• pp.64-71
• /
• 2019

Background: It is very difficult to distinguish between a radioactive contamination source and background radiation from natural radionuclides in the marine environment by means of online monitoring system. The objective of this study was to investigate a statistical process for triggering abnormal level of count rate data measured from our on-line seawater radioactivity monitoring. Materials and Methods: Count rate data sets in time series were collected from 9 monitoring posts. All of the count rate data were measured every 15 minutes from the region of interest (ROI) for $^{137}Cs$ ($E_{\gamma}=661.6keV$) on the gamma-ray energy spectrum. The Shewhart ($3{\sigma}$), CUSUM, and Bayesian S-R control chart methods were evaluated and the comparative analysis of determination methods for count rate data was carried out in terms of the false positive incidence rate. All statistical algorithms were developed using R Programming by the authors. Results and Discussion: The $3{\sigma}$, CUSUM, and S-R analyses resulted in the average false positive incidence rate of $0.164{\pm}0.047%$, $0.064{\pm}0.0367%$, and $0.030{\pm}0.018%$, respectively. The S-R method has a lower value than that of the $3{\sigma}$ and CUSUM method, because the Bayesian S-R method use the information to evaluate a posterior distribution, even though the CUSUM control chart accumulate information from recent data points. As the result of comparison between net count rate and gross count rate measured in time series all the year at a monitoring post using the $3{\sigma}$ control charts, the two methods resulted in the false positive incidence rate of 0.142% and 0.219%, respectively. Conclusion: Bayesian S-R and CUSUM control charts are better suited for on-line seawater radioactivity monitoring with an count rate data in time series than $3{\sigma}$ control chart. However, it requires a continuous increasing trend to differentiate between a false positive and actual radioactive contamination. For the determination of count rate, the net count method is better than the gross count method because of relatively a small variation in the data points.

• Journal of Radiation Protection and Research
• /
• v.46 no.1
• /
• pp.14-23
• /
• 2021

Background: For radiological protection and control, the International Commission on Radiological Protection (ICRP) provides the nominal risk coefficients related to radiation exposure, which can be extrapolated using the excess relative risk and excess absolute risk obtained from the Life Span Study of atomic bomb survivors in Hiroshima and Nagasaki with the dose and dose-rate effectiveness factor (DDREF). Materials and Methods: Since it is impossible to directly estimate the radiation risk at doses less than approximately 100 mSv only from epidemiological knowledge and data, support from radiation biology is absolutely imperative, and thus, several national and international bodies have advocated the importance of bridging knowledge between biology and epidemiology. Because of the accident at the Tokyo Electric Power Company (TEPCO)'s Fukushima Daiichi Nuclear Power Station in 2011, the exposure of the public to radiation has become a major concern and it was considered that the estimation of radiation risk should be more realistic to cope with the prevailing radiation exposure situation. Results and Discussion: To discuss the issues from wide aspects related to radiological protection, and to realize bridging knowledge between biology and epidemiology, we have established a research group to develop low-dose and low-dose-rate radiation risk estimation methodology, with the permission of the Japan Health Physics Society. Conclusion: The aim of the research group was to clarify the current situation and issues related to the risk estimation of low-dose and low-dose-rate radiation exposure from the viewpoints of different research fields, such as epidemiology, biology, modeling, and dosimetry, to identify a future strategy and roadmap to elucidate a more realistic estimation of risk against low-dose and low-dose-rate radiation exposure.

• Nuclear Engineering and Technology
• /
• v.51 no.1
• /
• pp.303-309
• /
• 2019

Tritium is an important nuclide that must be monitored for radiation safety management. In this study, HTO was orally administered to rats at the level of 37 kBq ($1{\mu}Ci$) or 370 kBq ($10{\mu}Ci$) to examine tissue distribution and excretion levels. After sacrifice, wet and dry tissue samples were weighed and analyzed for tissue free-water tritium (TFWT) and organically bound tritium (OBT). The mean tissue concentrations of TFWT (OBT) were 30.9 (17.8) and 4.4 (8.1) Bq/g on days 7 and 13 at the 37 kBq level and 30.8 (64.6) Bq/g on day 17 at the 370 kBq level. To assess the cytogenetic damage due to tritium exposure, a cytokinesis-blocked micronucleus (MN) assay was performed in blood samples from rats exposed to HTO for 14 and 21 days after oral administration. There was no significant difference in the MN frequencies between the control and exposed rats.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.10 no.3
• /
• pp.41-48
• /
• 2014

This paper provides the design of system software for the management of radiation dose that is generated by using computerized tomography(CT). Recently, the radiation leakage incident of Japanese nuclear power plant was in the news internationally and there is a growing interest not only in nuclear power plant but in medical radiation exposure. In spite of the fact that currently safety management of radiation is under control only the workers of the radiation involved, now the exposure management of patients have been required. As surgery and inspections using the radiation have increased, this medical radiation exposure is increasing too. But it is a real situation that medical institutions don't know the level of radiation exposure applied to the patient. Therefore, a system for managing the radiation exposure of a patient from the medical institution is required. This paper proposes a design of a software program that manages the radiation exposure of CT which is a typical imaging tool to use the radiation in the medical institution. By check the amount of radiation dose and set the limit of dose, we would be of help to optimize the medical exposure of the patient.

• Journal of radiological science and technology
• /
• v.30 no.4
• /
• pp.313-320
• /
• 2007

There are the Medical Radiation Health and Safety Act(the Patient Radiation Health and Safety Act, the Radiologic Technologist Act), the Medical Laboratory Technologist Act, the Physical Therapy Practice Act, and the Dental Hygienist Act, etc in America. However, Korea has only one Act for a medical radiologic technologist(including radiation therapy technologist, nuclear medicine technologist), medical laboratory technologist, physical therapist, occupational therapy examiner, dental hygienist, and so on. It is the Medical Technologist Act. Therefore, the Medical Radiation Health and Safety Act for a radiologic technologist(including radiation therapy technologist, nuclear medicine technologist) has to be enacted independently in Korea. It is the purpose of this Act to provide for the appropriate certification of persons using radioactive materials, equipment emitting ionizing radiation on humans or performing medical imaging for diagnostic and therapeutic purposes. In Korea, the radiologic technologist is a "fusion technologist" who is a person other than a licensed practitioner as a radiographer, radiation therapist, nuclear medicine technologist, computed tomography technologist, magnetic resonance technologist, mammographer, sonographer, medical dosimetrist, quality management technologist, etc. This Act will have some provisions related to the definitions, reserved title, scope of practice, specialized technologist, application for licensure, radiologic technology council, renewal, continuing education, the radiation control advisory commission, etc. This Act will ensure that quality radiation therapy treatments are delivered and that quality diagnostic information is presented for interpretation, which will lead to accurate diagnosis, treatment and cure. Accurate diagnosis can be provided only when a personnel is properly educated in technique, equipment operation and radiation safety. In the end, this Act will protect the civil right to health. By regulating the personnel responsible for performing those procedures, this Act will mean improved care for patients-higher quality images, improved accuracy, and less exposure to radiation.