• 대한디지털의료영상학회논문지
• /
• 제11권2호
• /
• pp.69-77
• /
• 2009

This study gives an account of the collateral standards in IEC 60601-1-3: 2008 specifying the general requirements for basic safety and essential performance of diagnostic X-ray equipment regarding radiation protection as it pertains to the production of X-rays. The collateral standards establish general requirements for safety regarding ionization radiation in diagnostic radiation systems and describe a verifiable evaluation method of suitable requirements regarding control over the lowest possible dose equivalent for patients, radiologic technologists, and others. The particular standards for each equipment can be determined by the general requirements in the collateral standard and the particular standard is followed in the risk management file. The guidelines for radiation safety of diagnostic radiation systems is written up in ISO 13485, ISO 14971, IEC 60601-1-3(2002)1st edition, medical electric equipment part 1-3, and the general requirements for safety-collateral standards: programmable electrical medical systems. Therefore the diagnostic radiation system protects citizens' health rights with the establishment and revisions of laws and standards for diagnostic radiation systems as a background for the general requirements of radiation safe guards applies, as an international trend, standards regarding the medical radiation safety management. The diagnostic radiation system will also assure competitive power through a conforming evaluation unifying the differing standards, technical specifications, and recognized processes.

• Radiation Oncology Journal
• /
• 제37권1호
• /
• pp.60-65
• /
• 2019

Purpose: The quality assurance (QA) chart rounds are multidisciplinary meetings to review radiation therapy (RT) treatment plans. This study focus on describing the changes in RT management based on QA round reviews in a single institution. Materials and Methods: After 9 full years of implementation, a retrospective review of all patients whose charts passed through departmental QA chart rounds from 2007 to 2015. The reviewed cases were presented for RT plan review; subcategorized based on decision in QA rounds into: approved, minor modifications or major modifications. Major modification defined as any substantial change which required patient re-simulation or re-planning prior to commencement of RT. Minor modification included treatment plan changes which didn't necessarily require RT re-planning. Results: Overall 7,149 RT treatment plans for different anatomical sites were reviewed at QA rounds. From these treatment plans, 6,654 (93%) were approved, 144 (2%) required minor modifications, while 351 (5%) required major modifications. Major modification included changes in: selected RT dose (96/351, 27%), target volume definition (127/351, 36%), organs-at-risk contouring (10/351, 3%), dose volume objectives/constraints criteria (90/351, 26%), and intent of treatment (28/351, 8%). The RT plans which required major modification according to the tumor subtype were as follows: head and neck (104/904, 12%), thoracic (12/199, 6%), gastrointestinal (33/687,5%), skin (5/106, 5%), genitourinary (16/359, 4%), breast (104/2387, 4%), central nervous system (36/846, 4%), sarcoma (11/277, 4%), pediatric (7/251, 3%), lymphoma (10/423, 2%), gynecological tumors (2/359, 1%), and others (11/351, 3%). Conclusion: Multi-disciplinary standardized QA chart rounds provide a comprehensive and an influential method on RT plans and/or treatment decisions.

• The Korean Journal of Pain
• /
• 제35권2호
• /
• pp.129-139
• /
• 2022

C-arm fluoroscopy is a useful tool for interventional pain management. However, with the increasing use of C-arm fluoroscopy, the risk of accumulated radiation exposure is a significant concern for pain physicians. Therefore, efforts are needed to reduce radiation exposure. There are three types of radiation exposure sources: (1) the primary X-ray beam, (2) scattered radiation, and (3) leakage from the X-ray tube. The major radiation exposure risk for most medical staff members is scattered radiation, the amount of which is affected by many factors. Pain physicians can reduce their radiation exposure by use of several effective methods, which utilize the following main principles: reducing the exposure time, increasing the distance from the radiation source, and radiation shielding. Some methods reduce not only the pain physician's but also the patient's radiation exposure. Taking images with collimation and minimal use of magnification are ways to reduce the intensity of the primary X-ray beam and the amount of scattered radiation. It is also important to carefully select the C-arm fluoroscopy mode, such as pulsed mode or low-dose mode, for ensuring the physician's and patient's radiation safety. Pain physicians should practice these principles and also be aware of the annual permissible radiation dose as well as checking their radiation exposure. This article aimed to review the literature on radiation safety in relation to C-arm fluoroscopy and provide recommendations to pain physicians during C-arm fluoroscopy-guided interventional pain management.

• 대한안전경영과학회지
• /
• 제17권4호
• /
• pp.199-206
• /
• 2015

The purpose of this study was to investigate radiation dose sensitivity due to displacement of human extremities in the water bolus box on radiation therapy. Water bolus box and human thigh with femur bone were constructed in computerized radiation therapy planning system to verify the absorbed dose. Two 6MV X-ray beams were irradiated bilaterally into water bolus box and then radiation dose were calculated each situation at displacement of middle axis of thigh from the center in water bolus box to right and left direction. Absorbed dose of thigh and femur bone increased by the distance of displacement. The maximum dose of thigh even increased 20% over than prescribed dose. This is in contrast to conventional concept of dose distribution in water bolus box. Based on this result, displacement of body site in the water bolus box have to be averted during radiation therapy.

• Journal of Astronomy and Space Sciences
• /
• 제39권2호
• /
• pp.51-57
• /
• 2022

Cosmic radiation exposure of the flight crews in Korea has been managed by Radiation Safety Management around Living Life Act under Nuclear Safety and Security Commission. However, the domestic flight crews are excluded from the Act because of relatively low route dose exposure compared to that of international flight crews. But we found that the accumulated total annual dose of domestic flight crews is far from negligible because of relatively long total flight time and too many flights. In this study, to suggest the necessity of management of domestic flight crews' radiation exposure, we statistically analyzed domestic flight crew's accumulative annual dose by using cosmic radiation estimation models of the Civil Aviation Research Institute (CARI)-6M, Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS), and Korean Radiation Exposure Assessment Model (KREAM) and compared with in-situ measurements of Liulin-6K LET spectrometer. As a result, the average exposure dose of domestic flight crews was found to be 0.5-0.8 mSv. We also expect that our result might provide the basis to include the domestic flight crews as radiation workers, not just international flight attendants.

• Nuclear Engineering and Technology
• /
• 제54권2호
• /
• pp.507-513
• /
• 2022

When X-ray energy above 8 MV is used, photoneutrons are generated by the photonuclear reaction, which activates the components of linear accelerator (linac). Safely managing the radioactive material, when disposing linac or replacing components, is difficult, as the standards for the radioactive material management are not clear in Korea. We surveyed the management status of radioactive components occurred from medical linacs in Korea. And we also measured the activation of each part of the discarded Elekta linac using a survey meter and portable High Purity Germanium (HPGe) detector. We found that most medical institutions did not perform radiation measurements when disposing of radioactive components. The radioactive material was either stored within the institution or collected by the manufacturer. The surface dose rate measurements showed that the parts with high surface dose rates were target, primary collimator, and multileaf collimator (MLC). ⁶⁰Co nuclide was detected in most parts, whereas for the target, ⁶⁰Co and ¹⁸⁴Re nuclides were detected. Results suggest that most institutions in Korea did not have the regulations for disposing radioactive waste from linac or the management procedures and standards were unclear. Further studies are underway to evaluate short-lived radionuclides and to lay the foundation for radioactive waste management from medical linacs.

• 한국방사선학회논문지
• /
• 제9권2호
• /
• pp.79-99
• /
• 2015

본 연구의 조사대상은 대구, 경북지역에 소재한 대학교에 재학 중인 방사선과를 전공하는 대학생을 조사대상으로 2014년 2월 3일부터 2월21일까지 설문조사를 실시하여 다음과 같은 결과를 얻었다. 1. 방사선피폭관리에 대한 지식에 대해서는 'X선의 차폐는 납이나 콘크리트로 된 물질이 가능 하다', '인체에서 생식선은 방사선에 매우 민감한 부분이다' 문항에서 가장 높은 점수를 보였고, '직업상 피폭선량은 규정된 5년간에 대해 평균하여 연간 20 mSv를 넘을 수 없다'는 방사선피폭관리에 대한 지식이 가장 낮은 점수를 보였다. 2. 방사선피폭관리에 대한 태도에 대해서는 '방사선피폭과 관련하여 정기적인 건강진단을 받아야한다'. '방사선 조사지역에서 작업 시 방호복을 착용해야한다'는 문항에서 가장 높은 태도 수준을 보였고, '방사선장치의 선량보정 (Calibration)을 위한 선량측정을 정기적으로 해야 한다'는 방사선피폭관리에 대한 태도에서 가장 낮은 태도수준을 보였다. 3. 방사선피폭관리에 대한 행위에 대해서는 '방사선 조사 시 방어벽(판) 뒤에서 작업을 한 다'. '방사선피폭관리에 관한 교육을 정기적으로 받는 다'는 문항에서 가장 높은 행위 수준을 보였고, '근무지의 방사선 관련 장비가 순조로운 작업 상태로 되어 있는가를 사용 전 점점(Check)한다'는 가장 낮은 행위 수준을 보였다.

• International Journal of Safety
• /
• 제11권1호
• /
• pp.33-36
• /
• 2012

Examples and experiences of risk management on radiation under prolonged exposure situation are shown. The accident of the Fukushima dai-ichi nuclear power plant after the great east Japan earthquake (11 March, 2011) elevates background level of environmental radiation around the east Japan. For example, ambient dose equivalent rate around Tohkatsu area next to Tokyo located about 200 km-south from the plant, is about 0.1-0.6 micro-Sv $h^{-1}$ mainly due to $^{134}Cs$ and $^{137}Cs$ falling on the ground soil. This level is about double or up to ten times higher than the genuine natural level around the area. International Commission on Radiological Protection (ICRP) recommends how to face the existing exposure situation; that is the prolonged exposure situation. Referring to ICRP's reports and/or related international/domestic documents, we have been discussing and acting to gain public's safety and relief, who have a possibility to be exposed to prolonged lower-dose radiation. Here, we introduce our several experiences on risk management, especially focusing on risk communication, radiation education to public, and stakeholder involvements into making decision in local governments on radiation protection, relating to the accident.

• International Journal of Safety
• /
• 제10권2호
• /
• pp.6-9
• /
• 2011

Examples and experiences of risk management on radiation under prolonged exposure situation are shown. The accident of the Fukushima dai-ichi nuclear power plant after the great east Japan earthquake (11 March, 2011) elevates background level of environmental radiation around the east Japan. For example, ambient dose equivalent rate around Tohkatsu area next to Tokyo located about 200 km-south from the plant, is about 0.1-0.6 micro-Sv $h^{-1}$ mainly due to $^{134}Cs$ and $^{137}Cs$ falling on the ground soil. This level is about double or up to ten times higher than the genuine natural level around the area. International Commission on Radiological Protection (ICRP) recommends how to face the existing exposure situation; that is the prolonged exposure situation. Referring to ICRP's reports and/or related international/domestic documents, we have been discussing how to manage this situation and acting to gain safety and relief of public, who have a possibility to be exposed to prolonged lower-dose radiation. Here, we introduce our several experiences on risk management, especially focusing on risk communication, radiation education to public, and stakeholder involvements into decision making in local governments on radiation protection, relating to the accident.

• 한국의학물리학회지:의학물리
• /
• 제29권4호
• /
• pp.123-136
• /
• 2018

The complex dose distribution and dose transfer characteristics of intensity-modulated radiotherapy increase the importance of precise beam data measurement and review in the acceptance inspection and preparation stages. In this study, we propose a process map for the introduction and installation of high-precision radiotherapy devices and present items and guidelines for risk management at the acceptance test procedure (ATP) and commissioning stages. Based on the ATP of the Varian and Elekta linear accelerators, the ATP items were checked step by step and compared with the quality assurance (QA) test items of the AAPM TG-142 described for the medical accelerator QA. Based on the commissioning procedure, dose quality control protocol, and mechanical quality control protocol presented at international conferences, step-by-step check items and commissioning guidelines were derived. The risk management items at each stage were (1) 21 ionization chamber performance test items and 9 electrometer, cable, and connector inspection items related to the dosimetry system; (2) 34 mechanical and dose-checking items during ATP, 22 multileaf collimator (MLC) items, and 36 imaging system items; and (3) 28 items in the measurement preparation stage and 32 items in the measurement stage after commissioning. Because the items presented in these guidelines are limited in terms of special treatment, items and practitioners can be modified to reflect the clinical needs of the institution. During the system installation, it is recommended that at least two clinically qualified medical physicists (CQMP) perform a double check in compliance with the two-person rule. We expect that this result will be useful as a radiation safety management tool that can prevent radiation accidents at each stage during the introduction of radiotherapy and the system installation process.