Abstract: The invention relates to a monitoring device (20) of the position of an assembly containing nuclear fuel (4) in a housing of a storage basket (2). According to the invention, it comprises at least one mobile stop device (24, 26, 28) and a position indicator (30) suitable for being held at a stop by the mobile stop device in a first position indicating that the assembly occupies a first position, said mobile stop device being arranged so as to be able to be placed, by means of contact with the assembly located in a second position in its housing, in a position enabling it to release the position indicator devised to move automatically from the first position to a second position indicating that the assembly occupies the second position.

Abstract: A device and method for identifying the tubes in a tubesheet, including locating a support element along a portion of the tubesheet with at least one means for identifying the location or condition of the adjacent tubes.

Abstract: The invention teaches means for detecting unauthorized tampering or substitutions of a device, and has particular utility when applied on a "seal" device used to secure a location or thing. The seal has a transparent body wall, and a first indicia, viz., a label identification is formed on the inside surface of this wall. Second and third indicia are formed on the outside surface of the transparent wall, and each of these indicia is transparent to allow the parallax angled viewing of the first indicia through these indicia. The second indicia is in the form of a broadly uniform pattern, viz, many small spaced dots; while the third indicia is in the form of easily memorized objects, such as human faces, made on a substrate by means of halftone printing. The substrate is lapped over the outside surface of the transparent wall.