PURPOSE: To improve storage safety and radiation control by providing an operation device which operates, from an end part, a pivoted door and a tube so provided as to provide a closed position and an open position and controls displacement between the closed position and open position of the door.

CONSTITUTION: When, with a container carrier 30 placed in a flask 20, a container 29 filled with a radioactive waste is housed, an front-end part of a prove holder 32 is connected to the carrier 30 by screwing a connection nut 40 into a screw 28 of the container carrier 30. At this point, a door 42 is at closed position, and a prove 34 is retracted in a tube 38. When the tube 38 is connected to the container carrier 30, the prove holder 32 is inserted in time transportation flask 20. An operator, by manipulating a handle 68, moves the door 42 to an open position which carries the prove 34. The prove holder 32 is rotated by 360° around an axis center of the tube 38, thus the inside of the flask is sweep- inspected circularly.