Occupational radiation exposure and gaseous radioactive releases of the Karlsruhe reprocessing plant

The occupational radiation exposure is analysed by different characteristic quantities and their main influencing factors are described. As characteristic quantities the annual collective dose, the mean individual dose, the number and values of contaminations and incorporations are used. The elements (burnup, cooling time) as well as a feedback of experience come out as main influencing parameters. The character of an experimental facility with the resulting modifications is of importance. The reported individual doses stay markedly below the applicable limits. The evaluation of the gaseous radioactive releases shows, that for most of the nuclides and groups of nuclides the release is determined by the duration of the reprocessing campaigne and the burnup. Besides that the cooling time and for all nuclides except C-14 and Kr-85 the emissions from the high active liquid waste tanks are of influence. A remarkable reduction of the release is achieved by the installation of an iodine filter in the offgas system. The release values lie up to two orders of magnitude below the authorized release limits. In three cases release limits were exceeded. For two of these events the exceeding was minor. In the third case the release limit per day for β-aerosols was exceeded by a factor of 6 because of the burn out of a drum. The release limits per month and per year were met, however. (orig./HP)