The radium applicator (Fig. 1) to be described subsequently (Grande, 1958) was constructed in order to improve radiation protection of personnel during loading and unloading. The applicator is cast from Vinatex Paste M.G.1227/H/NT. On heating to 160°C for approximately three hours, the milky plastic suspension becomes a rubber-like, elastic, transparent material (Hulbert and Groom, 1954).