Incineration system for the disposal of 125I-radioimmunoassay test tube wastes

Before incineration of disposed RIA test tubes, residual 125I radioactivity should be measured for the purpose of radiation safety. This confirmation method has been carried out according to the followings: (1) Residual 125I radioactivity of test tubes in the plastic bag was measured from outside with the low-energy γ-ray survey meter (S1371, Ohyo Kohken Co., Ltd.) newly developed by one of the authors. (2) Gaseous 125I released from the residual 125I-compounds in test tubes by radiation self decomposition was adsorbed by the activated carbon fiber filter(ACFF), and was measured. From the above 2 methods, the minimum detectable concentration of residual 125I in waste tubes would be reached under a level of about 100mBq/g (2.8x10-6μCi/g). (author)