Improvements in or relating to accessory-carrying members for radiation-protective screens and radiation-protective screens embodying same

969,897. Handling radio-active material. COMMISSARIAT A L'ENERGIE ATOMIQUE. Jan. 11, 1961 [Jan. 14, 1960], No. 1186/61. Heading B4Q. An arrangement permitting an accessory to be readily mounted in or removed from a radiation-protective screen F comprises, Figs. 1, 3, a rectangular member E 1 of shielding material having a circular opening 7. The member E 1 is of four pieces A, B, C, D having joining surfaces 8 . . . 11 of at least two facets to prevent the passage of radiation, the boundary edges 3 . . . 6 of the member E 1 also having two facets. As shown, all the facets are prismatic and form either a projecting prism (e.g. edges 3, 4) or a recessed prism (e.g. edges 5, 6). The surfaces 8, 9 are parallel to the same radial direction whereby the member E 1 may be mounted in an opening in the screen F, the piece A being the last piece to be positioned by movement in the radial direction P. The opening 7 is screw-threaded with a thread of rounded profile (Fig. 2, not shown) whereby it may receive an accessory having an external thread of similar profile. As shown in Fig. 3 the accessory comprises a glass 20 sealed to a threaded mounting 17 by cement 19. In a modification, Fig. 4 (not shown), the accessory is the pivotal mounting of a manipulator arm.