1.1 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 overall control of sterilization processes. This International Standard applies to indicators that show exposure to sterilization processes by means of physical and/or chemical change of substances, and which are used to monitor one or more of the variables required of a sterilization process. These chemical indicators are not dependent for their action on the presence or absence of a living organism. 1.2 This International Standard does not consider indicators for use in those processes that rely on physical removal of microorganisms, e.g. filtration. 1.3 This International Standard is not intended to apply to indicators for use in combination processes, for example, washer disinfectors or CIP (cleaning in place) and SIP (sterilization in place).