• Progress in Medical Physics
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• v.4 no.2
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• pp.3-7
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• 1993

In the 7th Steering Committee Meeting held in November 1986 in Suba, Fiji, the steering committee made a decision that the Korea Research Institute of Standards and Science (KRISS) coordinates the program of the regional intercomparison of ionizing radiation measurement. Through mutual communications with the Radiation Laboratory at KRISS, five countries (Australia, China, India, Japan and Malaysia) agreed to participate in the X-ray dosimetry standards intercomparison under the auspices of KRISS.

• Journal of Radiation Protection and Research
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• v.41 no.3
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• pp.274-281
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• 2016

Background: Whole-body counters are widely used to evaluate internal contamination of the internal presence of gamma-emitting radionuclides. In internal dosimetry, it is a basic requirement that quality control procedures be applied to verify the reliability of the measured results. The implementation of intercomparison programs plays an important role in quality control, and the accuracy of the calibration and the reliability of the results should be verified through intercomparison. In this study, we evaluated the reliability of 2 whole-body counting systems using 2 calibration methods. Materials and Methods: In this study, 2 whole-body counters were calibrated using a reference male bottle manikin absorption (BOMAB) phantom and a Radiation Management Corporation (RMC-II) phantom. The reliability of the whole-body counting systems was evaluated by performing an intercomparison with International Atomic Energy Agencyto assess counting efficiency according to the type of the phantom. Results and Discussion: In the analysis of counting efficiency using the BOMAB phantom, the performance criteria of the counters were satisfied. The relative bias of activity for all radionuclides was -0.16 to 0.01 in the Fastscan and -0.01 to 0.03 in the Accuscan. However, when counting efficiency was analyzed using the RMC- II phantom, the relative bias of $^{241}Am$ activity was -0.49 in the Fastscan and 0.55 in the Accuscan, indicating that its performance criteria was not satisfactory. Conclusion: The intercomparison process demonstrated the reliability of whole-body counting systems calibrated with a BOMAB phantom. However, when the RMC-II phantom was used, the accuracy of measurements decreased for low-energy nuclides. Therefore, it appears that the RMC-II phantom should only be used for efficiency calibration for high-energy nuclides. Moreover, a novel phantom capable of matching the efficiency of the BOMAB phantom in low-energy nuclides should be developed.

• Nuclear Engineering and Technology
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• v.52 no.10
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• pp.2379-2386
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• 2020

This paper presents the results of the first intercomparison exercise performed by the Korea retrospective dosimetry (KREDOS) working group using electron paramagnetic resonance (EPR) spectroscopy. The intercomparison employed the alanine dosimeter, which is commonly used as the standard dosimeter in EPR methods. Four laboratories participated in the dose assessment of blind samples, and one laboratory carried out irradiation of blind samples. Two types of alanine dosimeters (Bruker and Magnettech) with different geometries were used. Both dosimeters were blindly irradiated at three dose levels (0.60, 2.70, and 8.00 Gy) and four samples per dose were distributed to the participating laboratories. Assessments of blind doses by the laboratories were performed using their own measurement protocols. One laboratory did not participate in the measurements of Magnettech alanine dosimeter samples. Intercomparison results were analyzed by calculating the relative bias, E_n value, and z-score. The results reported by participating laboratories were overall satisfactory for doses of 2.70 and 8.00 Gy but were considerably overestimated with a relative bias range of 10-95% for 0.60 Gy, which is lower than the minimum detectable dose (MDD) of the alanine dosimeter. After the first intercomparison, participating laboratories are working to improve their alanine-EPR dosimetry systems through continuous meetings and are preparing a second intercomparison exercise for other materials.

• Journal of Radiation Protection and Research
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• v.19 no.2
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• pp.133-145
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• 1994

Recently, the Ministry of Science and Technology issued a Ministerial Ordinance (No 1992-15) about the technical criteria on personnel radiation dosimetry. In today's climate, it is important to demonstrate and document that the processor's systems and services to others meet national standards of quality. The purpose of this study is to verify the performance of the Teledyne PB-3 personnel dosimetry system that is generally used in Korea Atomic Energy Research Institute(KAERI) by intercomparison with Oak Ridge National Laboratory. The KAERI has been participated in this personnel dosimetry intercomparison study(PDIS) program since 1991 and it could be possible to test and calibrate personnel monitoring system. This report presents a summary and analysis of by about 50 dose equivalent measurements reported for PDIS-16 through 18 (1991 -1993) with emphasis on neutron dose equivalent sensitivity, accuracy and precision. Relationships of the PDIS results to occupational neutron monitoring and methods to improve personnel dosimetry performance are also discussed.

• Journal of the Korean Vacuum Society
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• v.4 no.2
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• pp.135-141
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• 1995

Spinning Rotor Gauge(SRG)를 전달표준기(transfer standard gauge)로 사용하여 한국표준과학연구원(KRISS)의 고진공표준과 이태리 표준연구소인 IMGC(Istituto 야 Metrologia Gustavo Colonnetti)고진공표준의 국제비교를 실시하였다. 그 방법은 SRG의 accommodation coefficient(s)를 각 연구실의 고진공표준기로 측정하여 그 결과를 비교하였다. 이 결과 두 기관에서 교정한 SRG 볼의 $\sigma$값의 평균차이는 0.696%로서 양국의 고진공표준은 오차범위내에서 일치하는 것으로 나타났다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.312-313
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• 2015

For the traceability of high current measuring sensors of high power testing department II(HPTD II) in Korea Electrotechnology Research Institute(KERI), additional comparison tests with reference test object were performed repeatedly. The first intercomparison has been carried out between the reference shunt for Asia and high current shunt of HPTD II in 2013. This paper compares the test results of the calibration in 2014 with them in 2015. The assigned new scale factor of high current sensors will be applied to high power tests in HPTD II until the next high current intercomparison.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.437-439
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• 2001

The plan of intercomparison test for high-current system was discussed concretely in the technical committee of STL in 2000. This paper describes the present state of the world, the plan & procedure of intercomparison test and test expenses for high-current system. In conclusion, this mentioned the matters that our country should prepare urgently.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1492-1493
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• 2007

This paper represents the development of national standard(NS) for switching impulse(SI) voltage measuring system rated 500 kV. A traceability of the NS to the international standard could be achieved by the intercomparison test with PTB(Physikalisch-Technische Bundesansalt). According to the IEC 60060-2, a measurement uncertainty was assessed. As a result of the tests, the measurement uncertainty and the characteristics of step response were satisfied with the requisite for NS.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.905-906
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• 2007

An intercomparison of ac shunts between the National Research Council of Canada and Korea Research Institute of Standards and Science is presented. The comparison was performed for the recently develop 1 A and 5 A current shunts at KRISS. The results of the both phase angle and ratio error of the resistive shunts are agree within the level of $\pm$1.5ppm and $\pm$5ppm respectively at 50 Hz.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.252-254
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• 2002

A new protocol for dosimetry in external beam radiotherapy is published by the Japan Society of Medical Physics (JSMP) in 2002. The protocol deals with proton and heavy ion beams as well as photon and electron beams, in accordance with IAEA Technical Report Series No. 398. To establish inter-institutional uniformity in proton beam dosimetry, an intercomparison program was carried out with the new protocol. The absorbed doses are measured with different cylindrical ionization chambers in a water phantom at a position of 30-mm residual range for a proton beam, that had range of 155 mm and a spread out Bragg peak (SOBP) of 60-mm width. As a result, the intercomparison showed that the use of the new protocol would improve the +/- 1.0 % (one standard deviation) and 2.7 % (maximum discrepancy) differences in absorbed doses stated by the participating institutions to +/- 0.3% and 0.9 %, respectively. The new protocol will be adopted by all of the participants.