High-radiation-exposure tasks in Korean pressurized heavy-water reactors.

This study analysed the occupational dose in Korean pressurized heavy-water reactors (PHWRs) and identified tasks involving high radiation exposure. The average individual dose was sufficiently low to be below the annual effective dose limit for radiation workers and is even lower than the dose limit for the general public. However, some workers received relatively higher doses than others.

Virtual reality-based neurological examination teaching tool(VRNET) versus standardized patient in teaching neurological examinations for the medical students: a randomized, single-blind study.

Background: The conventional methods for teaching neurological examination with real patients to medical students have some limitations if the patient with the symptom or disease is not available. Therefore, we developed a Virtual Reality-based Neurological Examination Teaching Tool (VRNET) and evaluated its usefulness in in teaching neurological examinations for the medical students.

Methods: In this prospective, randomized, single-blind study, we recruited 98 medical students and divided them into two groups: 1) A standardized patient(SP) group that received the clinical performance examination utilizing standard patients complaining of dizziness was provided neurological findings using conventional method such as verbal description, photographs, and video clips; 2) A SP with VRNET group that was provided the neurological findings using the newly developed tool.

A STUDY OF A DOSE CONSTRAINT FOR OCCUPATIONALLY EXPOSED WORKERS IN THE US NUCLEAR POWER PLANTS.

One of the most important issues in the nuclear power industry is the implementation of the 2007 Recommendations of the International Commission on Radiological Protection (ICRP) published in ICRP Publication 103. These recommendations include the implementation of the concept of dose constraints for occupationally exposed workers at nuclear power plants (NPPs). When considering these changes from a cost-benefit standpoint, the implementation of dose constraints is still highly controversial.

Simulated internal jugular vein cannulation using a needle-guiding device.

Background: Using a two-dimensional ultrasound-guided approach does not guarantee success during the first attempt at internal jugular vein cannulation. Our randomized, parallel simulation study examined whether a new disposable device could improve the success rate of the first attempt at ultrasound-guided internal jugular vein cannulation of a simulated internal jugular vein.

Methods: Eighty-eight participants were randomized to perform needle insertion for internal jugular vein cannulation of a phantom using the ultrasound-guided approach with (case group) or without (control group) this new device.

Applicability test of methods for discrimination between external and internal contamination using an ORTEC whole body counter.

Whole-body counters (WBCs) are generally used for monitoring internal radioactive contamination of radiation workers in nuclear power plants. However, it has been found that external contamination is occasionally counted as internal contamination. The previous study was conducted to provide guidance on measuring the exact internal radioactivity using a Canberra WBC.

Radiological effluents released and public doses from nuclear power plants in Korea.

As of the end of 2010, there were 20 commercially operating nuclear reactors in Korea. Releases of radioactive effluents from nuclear power plants (NPPs) have increased continuously; the total radioactivity of effluent amount released in 2010 was 547.12 TBq.

Dosimetry experiences and lessons learned for radiation dose assessment in Korean nuclear power plants.

Since the first Korean nuclear power plant (NPP), Kori 1, commenced operation in 1978, a total of 21 NPPs had been put into operation in Korea by the end of 2011. Radiation doses of NPP workers have been periodically evaluated and controlled within the prescribed dose limit. Radiation dose assessment is carried out monthly by reading personal dosemeters for external radiation exposure, which have traceability in compliance with strict technical guidelines.

A A field test for extremity dose assessment during outages at Korean nuclear power plants.

During maintenance on the water chamber of a steam generator, the pressuriser heater and the pressure tube feeder in nuclear power plants, workers are likely to receive high radiation doses due to the severe workplace conditions. In particular, it is expected that workers' hands would receive the highest radiation doses because of their contact with the radioactive materials. In this study, field tests for extremity dose assessments in radiation workers undertaking contact tasks with high radiation doses were conducted during outages at pressurised water reactors and pressurised heavy water reactors in Korea.

An analysis of the radiation field characteristics for extremity dose assessment during maintenance periods at nuclear power plants in Korea.

Workers who maintain the water chambers of steam generators during maintenance periods in nuclear power plants (NPPs) have a higher likelihood of high radiation exposure, even if they are exposed for a short period of time. In particular, it is expected that the hands of workers would receive the highest radiation exposure as a consequence of hand contact with radioactive materials. In this study, a characteristic analysis of inhomogeneous radiation fields for contact operations was conducted using thermoluminescent dosemeters for the whole body and extremities during maintenance periods at Korean NPPs.

An analysis of workers' tritium concentration in urine samples as a function of time after intake at Korean pressurised heavy water reactors.

In general, internal exposure from tritium at pressurised heavy water reactors (PHWRs) accounts for ∼20-40 % of the total radiation dose. Tritium usually reaches the equilibrium concentration after a few hours inside the body and is then excreted from the body with an effective half-life in the order of 10 d. In this study, tritium metabolism was reviewed using its excretion rate in urine samples of workers at Korean PHWRs.

A bioassay experience and lessons learned on the internal contamination of (131)I during a maintenance period in a Korean nuclear power plant.

During a maintenance period at a Korean nuclear power plant, internal exposure of radiation workers occurred by the inhalation of (131)I that was released into the reactor building from a primary system opening due to defective fuels. The internal activity in radiation workers contaminated by (131)I was immediately measured using a whole body counter (WBC). A whole body counting was performed again a few days later, considering the factors of equilibrium in the body.

Radiation fields and dose assessments in Korean nuclear power plants.

In the primary systems of nuclear power plants (NPPs), various radionuclides including fission products and corrosion products are generated due to the complex water chemistry conditions. In particular, (3)H, (14)C, (58)Co, (60)Co, (137)Cs, and (131)I are important or potential radionuclides with respect to dose assessment for workers and the management of radioactive effluents or dose assessment for the public. In this paper, the dominant contributors to the dose for workers and the public were reviewed and the process of dose assessment attributable to those contributors was investigated.

Selection of the most appropriate two-dosemeter algorithm for estimating effective dose equivalent during maintenance periods in Korean nuclear power plants.

The application of a two-dosemeter system with its algorithm, as well as a test of its use in an inhomogeneous high-radiation field, is described in this study. The goal was to improve the method for estimating the effective dose equivalent during maintenance periods at Korean Nuclear Power Plants (NPPs). The use of this method in Korean and international NPPs, including those NPPs in the USA and Canada, was also investigated.

Application and experience of a two-dosimeter algorithm for better estimation of effective dose during maintenance periods at Korea nuclear power plants.

The application of a two-dosimeter and its algorithm and a test of its use in an inhomogeneous high radiation field are described. The goal was to develop an improved method for estimating the effective dose during maintenance periods at Korean nuclear power plants (NPPs). The application and experience to KNPPs was evaluated using data for each algorithm from two-dosimeter results for an inhomogeneous high radiation field during maintenance periods at Korean NPPs.

Application of an improved in vivo counting program to Korean nuclear power plants.

During the in vivo counting of individuals using a whole body counter at nuclear power plants (NPPs), external skin contamination is occasionally mistaken for internal radioactive contamination. This not only confuses the degree of external contamination and internal contamination, but can also result in the excessively conservative estimation of radioactive contamination. In this paper, previous experiments to improve in vivo counting at NPPs are introduced briefly and the practical application of techniques presented in those experiments to Korean NPPs is demonstrated in detail.

Improvement to whole-body counting procedures at nuclear power plants.

A whole-body counter (WBC) is a device employed in nuclear power plants (NPPs) to identify radionuclides and measure the content of radioactivity in humans. In this study, several experiments were conducted to suggest an optimal and practical method to improve the accuracy of in vivo measurements using WBCs at NPPs. First, countings from the front and back using a phantom were carried out to set up a discrimination programme between internal and external radioactive contamination in NPPs.