Robustness of a Biological Indicator Resistance Test Rig

Abstract: The objective with the diploma work was to evaluate the robustness of the basic method and test rig used by Tetra Pak for testing the spores (biological indicators) resistance against liquid hydrogen peroxide. Tetra Pak uses liquid hydrogen peroxide as a sterilising agent in their filling machines to achieve an aseptic product. The resistance of the biological indicators is important to know when testing new filling machines and for validation of filling machines. The spore that was used in these tests was Bacillus spores. The assignment was to investigate the influence of different parameters. To compare the different testes a D-value is calculated. D-value is the time required to kill 90% of the viable spore population at a specified temperature.