Abstract: A disposable package is adapted to simulate the steam permeability and other qualities of the linen pack previously used to test the functioning of a steam sterilizer using a biological test device. The biological test device comprises spores on an appropriate carrier, either in a self-contained biological device or as a spore strip. The biological test device is placed within applicant's specially constructed package and the package is placed within the sterilizer, which is then cycled through a conventional sterilization cycle. During the sterilization cycle, applicant's package simulates the standard sterilizer linen pack previously used for such tests. After the sterilization cycle, sterility of the spore preparation is evaluated by incubating the spores in a culture medium to determine whether the spore population has been adequately destroyed.