This International Standard provides guidance for the selection, use and interpretation of results of chemical indicators used in process definition, validation, and routine monitoring and control of sterilization processes. This International Standard is applicable to chemical indicators for which International Standards exist (see ISO 11140 series). This International Standard is not applicable to those processes that rely on physical removal of microorganisms, e.g. filtration. This International Standard is not intended to apply to combination processes, for example, washer-disinfectors or flushing and steaming of pipelines.