The standard DIN EN 556-1 1) specifies requirements for when terminally sterilized medical devices may be labelled as sterile. Various committees are involved in the drafting of sterilization procedures, equipment, packaging and accessories.
The aim of standardization here is to ensure effective sterilization in the manufacturing or processing of medical devices in health care facilities and in industrial production.
On the subject of reprocessing the Robert Koch-Institute and the Federal Institute for Drugs and Medical Devices have drafted standards on "Hygiene Requirements for the Reprocessing of Medical Devices" which you may find in Appendix B of the Joint Recommendation from the Commission on Hospital Hygiene and Infection Protection at the Robert Koch Institute (RKI) and the Federal Institute for Drugs and Medical Devices (BfArM)

1) DIN EN 556-1, Sterilization of medical devices - Requirements for medical devices marked "STERIL" - Part 1: Requirements for medical devices sterilized in their final packaging