This International Standard provides guidance for the selection, use and interpretation of results from application of biological indicators when used in the development, validation and routine monitoring of sterilization processes. 1.1 Exclusions This International Standard does not consider those processes that rely solely on physical removal of microorganisms, e.g., filtration. This International Standard is not intended to apply to combination processes using, for example, washerdisinfectors or flushing and steaming of pipelines. This International Standard does not specify requirements for the selection and use of biological indicators intended to monitor vaporised hydrogen peroxide processes for isolator and room biodecontamination processes at atmospheric pressure. This International Standard is not intended to apply to liquid immersion sterilization processes.