[en] Because the Great East Japan Earthquake and subsequent tsunami which occurred on March 11, 2011 was of such a tremendous scale that it easily surpassed previous assumptions, they inflicted great damage across a broad region of eastern coast of Japan and not just near near the seismic center. Several years have passed since the earthquake and tsunami, during which the experiences of many vessels struck by the large tsunami have been shared and safety guidelines issued by several organizations. While the Nuclear Fuel Fuel Transport Co., Ltd. ('NFT') has implemented a variety of measures since March 2011, we would like to examine other cases of vessels' behavior during the disaster to further deduce lessons to be learned. The purpose of this paper is to enhance the safe operation of our transport vessels to reflect these lessons learned. (author)