• Journal of Radiation Protection and Research
• /
• v.40 no.4
• /
• pp.211-215
• /
• 2015

In case of radiation emergencies, radioactive materials released into environments can cause internal exposure of members of the public. Even though whole body counters are widely used for direct measurement of internally deposited radionuclides, those are not likely to be used at the field to rapidly screen internal exposure. In this study, we estimated the counting efficiencies of portable NaI detector for different size BOMAB phantoms using Monte Carlo transport code to apply handheld gamma spectrometers for rapid screening of internal exposure following radiological accidents. As a result of comparison for two counting geometries, counting efficiencies for sitting model were about 1.1 times higher than those for standing model. We found, however, that differences of counting efficiencies according to different size are higher than those according to counting geometry. Therefore, we concluded that when we assess internal exposure of small size people compared to the reference male, the body size should be considered to estimate more accurate radioactivity in the human body because counting efficiencies of 4-year old BOMAB phantom were about 2.4~3.1 times higher than those of reference male BOMAB phantom.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.14 no.2
• /
• pp.41-44
• /
• 2010

Purpose: Along with recent advances in PET/CT instrumentation and imaging technology, the number of patients has also been steadily increasing. This resulted in the increased radiation exposure to radiation workers in PET/CT rooms. In this study, we installed a radiation shield and investigated whether it could reduce radiation exposure to the workers and thus enhance job satisfaction. Materials and Methods: A radiation shield is composed of 5 cm thick lead and has a structure in which a radiation worker sits and watches a patient through lead glass while injecting radiopharmaceutical to the patient. Quarterly absorbed dose of radiation workers was measured using thermoluminescence dosimeters (TLD) and the results were compared for six months each before and after installation of the radiation shield. Exposure dose was also measured using a pocket dosimeter placed at the same location in the front and the back of the radiation shield. In addition, frequency of use of the shield and job satisfaction of radiation workers were investigated using a survey. Results: Quarterly absorbed dose of radiation workers was 2.70 mSv on average before installation of new radiation shield, whereas that dropped to 2.13 mSv after installation of radiation shield, reducing radiation exposure dose by 21%. Exposure dose on the front side of the shield was 61.2 R, whereas that on the back side of shield was 2.8 R. According to the survey, 85% of workers used the shield and were satisfied with the outcome: each radiation worker made injections to patients average of 6.5 times/day and preferred sitting to standing while injecting radiopharmaceutical to patients. Conclusion: Use of radiation shield reduced the exposure dose of radiation workers, which is the ultimate goal of radiation protection to minimize radiation exposure and is an appropriate method for the improvement of hospital working environment. Furthermore, we found that use of radiation shield not only relieves physical and psychological burden of radiation workers but also enhances job satisfaction. This result indicates that use of radiation shield is important for improvement of the radiation workers' job environment in terms of radiation protection.

• The Journal of the Korean dental association
• /
• v.52 no.3
• /
• pp.147-152
• /
• 2014

Recently the patient exposure by medical and dental x-ray examination has grown rapidly and diagnostic radiology represents the largest source of man-made radiation. For the patient protection, the principle of justification and optimization should be followed. All the radiographic examinations have to show a potential benefit to the patient weighing against the potential risk. After they are justified, the radiographic exposure should be kept as low as reasonably achievable, taking into account economic and social factors. For the safe use of radiation in dentistry, the radiation safety management in accordance with the legislation is important. The present status and the future of radiation safety management in dental radiology in Korea and other country will be discussed.

• The Journal of Korean Society for School & Community Health Education
• /
• v.8 no.1
• /
• pp.69-77
• /
• 2007

Background & Objectives: International radiation protection committee recognized the importance of radiation protection from medical practices because the exposure to the radiation in medical practice is higher than any other exposure. The factors on knowledge, attitude and practice of radiation safety of the medical workers engaged in radiation were analyzed in order to improve radiation safety technology. Method: Questionnaires were used for 1200 radiation workers in medical institution from July 23 through September 4 and collected for analysis. Results: Different level of safety measures were practiced by age, marital status, career, and medical facility. The difference was statistically significant. Higher levels of safety measures were practiced in the age group of 50s and married persons. The workers who have more than 20 years experience have higher level of safety measures. The workers of health centers have higher level of safety measures to compare with other workers. The factors which give more concerns on safety practice were self efficacy, practice and knowledge in order. Conclusion: Safety conscious operators should get additional education program to maintain higher level of safety. The operators who do not have much safety concern should be intensive training program for self efficacy and safety.

• Journal of the Korean Society of Radiology
• /
• v.3 no.1
• /
• pp.23-28
• /
• 2009

Medical radiation therapy using radioactive isotope I-131 is an extremely critical part of nuclear medicine. It is important to evaluate patients' radiation exposure dose for the safe handling of radiation in the medical area. Cautions related to patients' exposure to radiation are as follows. First, the dose should not exceed the level required for medical purpose. Second, unnecessary exposure should be avoided. Third, it should be considered carefully first whether the same medical purpose is attainable without the use of radiation. For these purposes, we need to evaluate patients' radiation exposure dose. Thus, in order to promote the safety of patients in medical wards, this study sampled air using an air sampler and measured the radioactivity of the sample using a gamma counter. According to the results of measuring I-131 in medical wards, the highest level, the average and the lowest level were $404.11Bq/m^3$, $228.27Bq/m^3$ and $126.17Bq/m^3$, respectively.

• The Korean Journal of Pain
• /
• v.35 no.2
• /
• 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.

• Journal of radiological science and technology
• /
• v.42 no.2
• /
• pp.105-111
• /
• 2019

A medical personnel could be placed beside a patient together in CT room to do Ambu-bag for a seriously ill patients or emergency patient. At this time, the medical personnel can be exposed indirect radiation unnecessarily. In this case, it is necessary to recognize indirect radiation dose levels and methods to reduce them using actual clinical CT protocols such as Chest, Abdomen, and Brain CT. We researched surface radiation dose with or without radiation protectors such as apron and goggles according to different distances far from gantry using two different CT scanners (Fixed MDCT and mobile CT). As a result, for Chest, Abdomen, and Brain CT with Fixed MDCT, indirect radiation dose on thorax portion were 0.047, 0.089, 0.034 mSv without apron. Also, those with apron were 0.007, 0.012, 0.006 mSv. In case of mobile CT, it was 0.014 mSv without apron and 0.005 mSv with apron. By using protectors and increasing the distance, we could reduce it to 97%. Systematic management is necessary based on the measured data in order to minimize radiation damage due to indirect exposure dose.

• Journal of Radiation Protection and Research
• /
• v.46 no.3
• /
• pp.120-126
• /
• 2021

Background: This paper aims to evaluate the clinical utility and radiation dosimetry, for the mobile X-ray imaging of patients with known or suspected infectious diseases, through the window of an isolation room. The suitability of this technique for imaging coronavirus disease 2019 (COVID-19) patients is of particular focus here, although it is expected to have equal relevance to many infectious respiratory disease outbreaks. Materials and Methods: Two exposure levels were examined, a "typical" mobile exposure of 100 kVp/1.6 mAs and a "high" exposure of 120 kVp/5 mAs. Exposures of an anthropomorphic phantom were made, with and without a glass window present in the beam. The resultant phantom images were provided to experienced radiographers for image quality evaluation, using a Likert scale to rate the anatomical structure visibility. Results and Discussion: The incident air kerma doubled using the high exposure technique, from 29.47 µGy to 67.82 µGy and scattered radiation inside and outside the room increased. Despite an increase in beam energy, high exposure technique images received higher image quality scores than images acquired using lower exposure settings. Conclusion: Increased scattered radiation was very low and can be further mitigated by ensuring surrounding staff are appropriately distanced from both the patient and X-ray tube. Although an increase in incident air kerma was observed, practical advantages in infection control and personal protective equipment conservation were identified. Sites are encouraged to consider the use of this technique where appropriate, following the completion of standard justification practices.

• Journal of The Korean Society of Clinical Toxicology
• /
• v.11 no.2
• /
• pp.101-105
• /
• 2013

Purpose: This study was conducted in order to determine the relationship between the number of portable X-rays and the radiation exposure dose for emergency medical service providers working in the emergency department (ED). Methods: A prospective study was conducted from February 15, 2013 to May 15, 2013 in the ED in an urban hospital. Six residents, seven emergency medical technicians (EMT), and 24 nurses were enrolled. They wore a personal radiation dosimeter on their upper chest while working in the ED, and they stayed away from the portable X-ray unit at a distance of at least 1.8 m when the X-ray beam was generated. Results: The total number of portable x-rays was 2089. The average total radiation exposure dose of emergency medical service providers was $0.504{\pm}0.037$ mSv, and it was highest in the EMT group, 0.85(0.58-1.08) mSv. The average of the total number of portable X-rays was highest in the doctor group, 728.5(657.25-809). The relationship between the number of portable X-rays and the radiation exposure dose was not statistically significant(-0.186, p=0.269). Conclusion: Under the condition of staying away from the portable X-ray unit at a distance of least 1.8 m, the relationship between the number of portable X-rays and the radiation exposure dose was not statistically significant.

• The Korean Society of Law and Medicine
• /
• v.23 no.2
• /
• pp.97-118
• /
• 2022

The use of diagnostic radiation in medical institutions is rapidly increasing. Accordingly, the collective effective dose is on the rise every year. Therefore, it is necessary to reduce the radiation exposure of the person undergoing the radiation examination as low as reasonably achievable. And we must establish a legal system to perform the safe management of radiation for diagnosis efficiently. In this way, I went over the problems of the Act and Subordinate Statutes regarding radiation safety management for diagnosis. As a result, the main contents are as follows. First, in the 「Medical Service Act」, there is no basis for the Safety Inspection Institute of Radiation and Radiation Exposure Measuring Institutes. And there are no provisions concerning delegation of administrative disposition. Therefore, it is necessary to secure legal justification by providing the basis for the Safety Inspection Institute of Radiation along with Radiation Exposure Measuring Institutes and the basis for administrative dispositions against these institutions in the 「Medical Service Act」. Second, the 「Rules on the Installation and Operation of Special Medical Equipment 」 should be integrated with the 「Rules on the Safety Management of Radiation Generators for Diagnostics」 to unify administrative procedures such as reporting for radiation special medical equipment for diagnosis. Third, in the case of violating the diagnostic radiation safety management standards in the 「Rules on the Safety Management of Radiation Generators for Diagnostics」, it is necessary to supplement the insufficient sanctions such as administrative disposition. Fourth, regulating diagnostic radiation and therapeutic radiation used in medical institutions with the dual legal system of the 「Medical Act」 and the 「Nuclear Safety Act」 is not efficient in the safety management of diagnostic radiation. Therefore, it is necessary to uniformly regulate diagnostic radiation and all medical radiation, including therapeutic radiation and nuclear medicine, in the 「Medical Service Act」 system.