Point tritium radioluminescent sources

Radioluminescent sources are elements, which generate light obtained as effect of the action of an ionizing radiation emitter on a substance with luminescent properties. The most used at present are sealed sources of Beta Light type, which contain gas tritium encapsulated in glass cells. The inner walls of such a cell have deposed a semitransparent thin layer of ZnS based phosphor. Since the source cell is built from easy breakable materials, the incidents associated with sources tightness breaking are relatively frequent. In these cases, the radionuclide is rapidly and totally released in the atmosphere. By replacement of tritium gas with tritium labelled polymers radiobiological and radio-ecological effects were diminished. In this paper the experimental results regarding the preparation of point radioluminescent sources were presented. These contain polyethyl-phenyl siloxanes labelled with tritium. This study has been devoted to: obtaining of tritium labelled syloxanic polymers, obtaining the glass bulb, deposition of radioluminescent paints and sealing techniques. The radioluminescent sources obtained have the following characteristics: luminance within 50-150 μLa range, 1.5 ± 0.1 mm diameter, 5 ± 0.3 mm height, per source activity between 370 and 925 mBq. (authors)