COMPATIBILITY REVIEW OF JAPANESE LARGE COMPONENTS TRANSPORT WITH APPENDIX VII OF TS-G-1.1

The need for large component transport has arisen due to the retirement and dismantlement of some facilities, as well as component degradation requiring replacement to provide for continued operation at other facilities. In some European countries and the US, feed-water heaters, which are classified as SCO-I, have been transported unpackaged as type IP-1, and steam generators, which are classified as SCO-II, have been transported unpackaged under “Special Arrangements”. On the basis of these experiences, IAEA has made “Guidance for transport of large components under special arrangements” in Appendix VII of TS-G1.1. We reviewed the compatibility of typical Japanese large components with the requirements of Appendix VII. First we evaluated inner-surface contamination of a steam generator with the data on the dose rates on the outside surface. In this evaluation, we calculated the activity intake (QINT), the maximum radiation level on the outside shell of the component, the external radiation level at 3 m and the strength of the tie down system. We also checked the suitable methods for inspection and evaluation.