This AAMI technical information report (TIR) provides guidance to augment information and requirements for parametric release provided in ANSI/AAMI/ISO 11135:1994, Medical devices? Validation and routine control of ethylene oxide (EO) sterilization. This TIR is intended to assist those individuals using ANSI/AAMI/ISO 11135:1994 in understanding the steps necessary to develop and validate an ethylene oxide sterilization process that meets the standard?s requirements for parametric release. This TIR also provides guidance for choosing the appropriate actions where alternatives are given. The guidance in this TIR is limited to the sections of the standard that specifically address parametric release.