RADIOLOGICAL SAFETY EXPERIENCE IN THE FABRICATION OF ALLOY PLATE FUELS BEARING U-233 PU/

The first incidence of U-233-bearing fuel fabrication in India was the production of aluminum-clad Al-U-233 alloy fuel for the Kamini resear ch reactor. The reactor physics experiments for this fuel are now bein g carried out in the Purnima III critical assembly, where Al-Pu alloy plate fuels will also be used. Both types of fuels were fabricated in the radiometallurgy laboratories of Bhabha Atomic Research Centre. The hazard potential of each step, evaluated from the site-specific radio logical field data, is summarized The parameters analyzed for this pur pose include external and internal radiation hazards, contamination ha zards, age of fuel, material (i.e., time after separation), and experi mental thermoluminescent detector exposure data. Gamma spectrometric d ata of the finished fuel plates were also analyzed for their utility i n checking the material inventory. The collective dose equivalent from the fabrication operations for 12 subassemblies (9 bearing 233 U and 3 bearing plutonium) was 67 mSv, arising from external exposures only. The internal exposure was nil. Fabrication of fuel plates constituted >60% of the total exposure. Fabrication of fuel subassemblies and qua lity control inspection at all the stages accounted for the remaining radiation exposure. Handling of U-233/Pu-bearing fuels is likely to in crease in the years ahead in India. In this context, analysis of radio logical field data has yielded useful guidelines for future work.