• The Korean Journal of Pain
• /
• v.27 no.2
• /
• pp.162-167
• /
• 2014

Background: Although a physician may be the nearest to the radiation source during C-arm fluoroscope-guided interventions, the radiographer is also near the fluoroscope. We prospectively investigated the radiation exposure of radiographers relative to their location. Methods: The effective dose (ED) was measured with a digital dosimeter on the radiographers' left chest and the side of the table. We observed the location of the radiographers in each procedure related to the mobile support structure of the fluoroscope (Groups A, M and P). Data about age, height, weight, sex, exposure time, radiation absorbed dose (RAD), and the ED at the radiographer's chest and the side of the table was collected. Results: There were 51 cases for Group A, 116 cases for Group M and 144 cases for Group P. No significant differences were noted in the demographic data such as age, height, weight, and male to female ratio, and exposure time, RAD and ED at the side of the table. Group P had the lowest ED ($0.5{\pm}0.8{\mu}Sv$) of all the groups (Group A, $1.6{\pm}2.3{\mu}Sv$; Group M, $1.3{\pm}1.9{\mu}Sv$; P < 0.001). The ED ratio (ED on the radiographer's chest/ED at the side of the table) of Group A was the highest, and the ED radio of Group P was the lowest of all the groups (Group A, $12.2{\pm}21.5%$; Group M, $5.7{\pm}6.5%$; Group P, $2.5{\pm}6.7%$; P < 0.001). Conclusions: Radiographers can easily reduce their radiation exposure by changing their position. Two steps behind the mobile support structure can effectively decrease the exposure of radiographers by about 80%.

• Advanced Industrial SCIence
• /
• v.2 no.3
• /
• pp.1-7
• /
• 2023

Recently, it is increasing that a issue of concern about radiation exposure. It affects soil, water, air, crops, etc., and in the long term, environmental pollution and food pollution occur, and it is considered to cause social problems and economic damage. Radiation exposure causes diseases and health problems, but as a method for diagnosing diseases, nuclear medicine tests such as X-ray imaging, CT, and PET-CT are conducted, and radiation isotopes are exposed for the purpose of cancer treatment. A Hungarian case study on radiation in water, particularly drinking water, following the release of radioactive waste from Fukushima, and an examination of the Larsemann Hills area in Antarctica, found that it was within the prescribed radioactivity limits of drinking water recommended by the World Health Organization. We looked at radioprotective agents, focusing on DNA damage, cell and organ damage, and cancer, and also investigated various literatures on ACE inhibitors, antioxidants, and natural substances among restoration materials. Although exposed to radiation in everyday life, the reason why it can be safe is probably because there is a radiation protection material and a recovery material for radiation exposure, so we are trying to find possible materials.

• 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.

• Radiation Oncology Journal
• /
• v.2 no.1
• /
• pp.25-32
• /
• 1984

The pathological changes of stomach of the rat following 1,000 rad and 1,800 rad single exposure by Cobalt-60 has been made with 50 experimental rats. The dose of 1,000 rad and 1,800 rad single exposure were equivalent of biologic effect of 2,500 rad in 2 1/2 weeks and 6,000 rad in 6 weeks. Following single exposure, the groups of rat were terminated in 1, 2, 4, 8, 12 weeks intervals and the stomach were fixed to formalin solution immediatly after dissection. The pathological changes were as follows : 1. Following 1,000 rad single exposure, the stomach show only mild to moderate submucosal edema in 4,8,12 weeks group. 1 and 2 weeks group show no changes. 2. Following 1,800 rad single exposure, $32\%(8/25)$ of rats were dead by radiation effect and all other groups of stomach revealed variable pathological changes such as submucosal edema, squamous dysplasia, squamous papilloma as well as squamous cell carcinoma. 3. Optimal tolerance dose to the stomach was $4,500\~5,000$rad when irradiation given by supervoltage. The entire stomach was included within the irradiation field, the dose to the stomach should not exceed 6,000 rad. 4. In conclusion, the radiation injury to the stomach were more direct radiation effects to the gastric mucosa rather than secondary changes of radiation injured vessels.

• Journal of Radiation Protection and Research
• /
• v.12 no.1
• /
• pp.54-60
• /
• 1987

The quasi-exposure rate and the quasi-effective energy of the natural radiation in the field at 47 monitoring points around nuclear power plants have been studied with the pair filter thermoluminescence dosimeter system. The results of the six years observation showed that the relationship between the quasi-exposure rate $X_q$, and quasi-effective energy $E_q$ can be represented as a hyperbolic function: $X_q=A+C/(E_q-B)$, where the constants A and B correspond to the quasi-exposure rate of cosmic-rays and the minimum quasi-effective energy of natural radiation, respectively. Furthermore, the constant A is in close agreement with the values obtained by using ionization chambers and scintillation detectors. The constant B is approximately 0.68 MeV, closely corresponding to the mean energy of the photons emitted from natural uranium.

• Environmental Analysis Health and Toxicology
• /
• v.18 no.4
• /
• pp.237-242
• /
• 2003

Single cell gel electrophoresis (SCGE) was used to the experiment with the variation on the amount of smoking and low dose radiation exposure to find how much the Lymphocyte DNA was damaged, and especially for whom smoke a lot(about 20 or more than 20 cigarettes a day) it was found to be highly damaged. While, the damage of 'not more than 20 cigarettes a day' was found to be not so much significant as like for whom smoke about or more than 20 cigarettes a day And, according to the different amount of the radiation exposure, the Lymphocyte DNA was found to be considerably damaged for 0-13m Sv (P<0.01), it was not able to prove the relationship between the DNA damage and the radiation exposure.

• Journal of Biomedical Engineering Research
• /
• v.38 no.5
• /
• pp.256-263
• /
• 2017

By using the buildup characteristics of the radiophotoluminescence glass dosimeter(RPLGD), it is aimed to help the measurement of the accurate dose by measuring the radiation dose according to the time of the glass element. Five glass elements were arranged on the table and the source to image receptor distance(SID) was set to 100 cm for the build-up radiation dose measurement of the fluorescent glass dosimeter glass element(GD-352M). Radiation doses and saturation rates were measured over time according to irradiation time, with the tube voltage (30, 60, 90 kVp) and tube current (50, 100 mAs) Repeatability test was repeated ten times to measure the coefficient of variation. The radiation dose increased from 0.182 mGy to 12.902 mGy and the saturation rate increased from 58.3% with increasing exposure condition and time. The coefficient of variation of the glass elements of the fluorescent glass dosimeter was ranged from 0.2 to 0.77 according to the X - ray exposure conditions. X - ray exposure showed that the radiation dose and saturation rate were increased with buildup characteristics, and degeneration of glass elements was not observed. The reproducibility of the variation coefficient of the radiation generator was included within the error range and the reproducibility of the radiation dose was excellent.

• Nuclear Engineering and Technology
• /
• v.55 no.1
• /
• pp.270-277
• /
• 2023

Exposure to ionizing radiation induces free radicals in human nails. These free radicals generate a radiation-induced signal (RIS) in electron paramagnetic resonance (EPR) spectroscopy. Compared with the RIS of tooth enamel samples, that in human nails is more affected by moisture and heat, but has the advantages of being sensitive to radiation and easy to collect. The fingernail as a biological sample is applicable in retrospective dosimetry in cases of localized hand exposure accidents. In this study, the dosimetric characteristics of fingernails were analyzed in fingernail clippings collected from Korean donors. The dose response, fading of radiation-induced and mechanically induced signals, treatment method for evaluation of background signal, minimum detectable dose, and minimum detectable mass were investigated to propose a fingernail-EPR dosimetry protocol. In addition, to validate the practicality of the protocol, blind and field experiments were performed in the laboratory and a non-destructive testing facility. The relative biases in the dose assessment result of the blind and field experiments were 8.43% and 21.68% on average between the reference and reconstructed doses. The results of this study suggest that fingernail-EPR dosimetry can be a useful method for the application of retrospective dosimetry in cases of radiological accidents.

• Journal of the Korean Society of Radiology
• /
• v.5 no.4
• /
• pp.195-200
• /
• 2011

The purpose of this study is to investigate the dose of radiation exposure to radiation-related workers in a hospital setting, thus increasing awareness of the health risk to the radiation-related workers. The result of the analysis showed the average dose of radiation exposure to radiation-related workers in hospital K was $0.75{\pm}0.26mSv$ in 2008, $0.67{\pm}0.30mSv$ in 2009, and $0.92{\pm}0.33mSv$ in 2010. The average dose of radiation exposure in hospital P was $0.43{\pm}0.13mSv$ in 2008, $0.43{\pm}0.20mSv$ in 2009, and $0.33{\pm}0.85mSv$ in 2010. The average dose of radiation exposure in hospital K by age group was 13.39mSv for age 20 to 29, 8.37mSv for age 30 to 39, 1.19mSv for age 40 to 49, 0.28mSv for age 50 to 59, and 0.32mSv for age 60 to 69 The average dose of radiation exposure in hospital P by age group was 0.33mSv for age 20 to 29, 1.41mSv for age 30 to 39, 0.83mSv for age 40 to 49, 1.66mSv for age 50 to 59, and 1.12mSv for age 60 to 69. Moreover, the average radiation exposure to radiation-related workers over 3 year period by gender group in hospital K was $2.92{\pm}1.03mSv$ for male group and $0.94{\pm}0.93mSv$ for female group. The average radiation exposure over 3 year period by gender group in hospital P was $0.66{\pm}0.18mSv$ for male group and $1.80{\pm}0.60mSv$ for female group. Persons working in diagnostic radiology department received mean of $1.65{\pm}1.54mSv/year$, mean $1.17{\pm}0.82mSv/year$ in radiation oncology, mean $1.79{\pm}1.42mSv/year$ at nuclear medicine department and mean $0.99{\pm}0.51mSv/year$ at other departments. Radiation exposure was higher than that of other departments(p<0.05). Doctors and technologists received higher radiation exposure (mean $1.75{\pm}1.17mSv/year$, $1.60{\pm}1.39mSv/year$ each) than other workers(p<0.05). Measurement and evaluation of radiation exposure in radiation-related workers should be widely conducted accurately and consistently in the radiation-related occupational setting so that people in these occupational settings are more aware of the risk from radiation exposure, and thus give more attention and caution to decrease radiation exposure. It would be essential to minimize accumulated radiation dose in the radiation-related occupational setting in order to maintain and improve the health of radiation-related workers.

• Journal of Veterinary Clinics
• /
• v.40 no.6
• /
• pp.429-437
• /
• 2023

In veterinary medicine, most radiographic images are obtained by restraining patients, inevitably exposing the restrainer to secondary scattered radiation. Radiation exposure can result in stochastic reactions such as cancer and genetic effects, as well as deterministic reactions such as skin burns, cataracts, and bone marrow suppression. Radiation-shielding equipment, including aprons, thyroid shields, eyewear, and gloves, can reduce radiation exposure. However, the risk of radiation exposure to the upper arms, face, and back remains, and lead aprons and thyroid shields are heavy, restricting movement. We designed a new radiation-shielding system and compared its shielding ability with those of conventional radiation-shielding systems. We hypothesized that the new shielding system would have a wider radiation-shielding range and similar shielding ability. The radiation exposure dose differed significantly between the conventional and new shielding systems in the forehead, chin, and bilateral upper arm areas (p < 0.001). When both systems were used together, the radiation-shielding ability was better than when only one system was used at all anatomical locations (p < 0.01). This study suggests that the new radiation-shielding system is essential and convenient for veterinary radiation workers because it is a step closer to radiation safety in veterinary radiography.