National Standard Reference Center from Ministry of Trade Industry and Energy at Dec.30 2008. The fields of designation were nuclear fuel and energy materials. NFDC produces standard reference data of nuclear fuel and materials. To ensure reliability of experimental data uncertainty should be estimated. There are two kinds of uncertainty: A-type uncertainty from tester and B-type uncertainty from experimental equipments. To reduce the former, the measurement should be repeated for sufficient amount of times, and to reduce the latter type uncertainty all equipment have to be calibrated. In this study the uncertainty evaluation process of thermo-gravimetric analyzer (TGA) data was developed. The self calibration was performed using the standard mass and correction factor was obtained. The measurement model of oxidation was established, factors affected to uncertainty was analyzed, uncertainty of each factor using sensitivity coefficient was evaluated, combined uncertainty was calculated, and expanded uncertainty using coverage factor was calculated. It is believed that the uncertainty evaluation process of TGA data developed in this study will be helpful for increasing reliability and stability evaluation of nuclear fuel and spent fuel.

• Kweonho Kang(Korea Atomic Energy Research Institute, 111, Daedeok-daero 989beon-gil, Yuseong-gu, Daejeon) Corresponding author
• Byeongjoo Yoon(Korea Atomic Energy Research Institute, 111, Daedeok-daero 989beon-gil, Yuseong-gu, Daejeon)