ISO 25424:2018

1.1 Inclusions

1.1.1 This document specifies requirements for the development, validation and routine control of a low temperature steam and formaldehyde (LTSF) sterilization process for medical devices using a mixture of low temperature steam and formaldehyde as sterilizing agent and which operates below ambient pressure.

NOTE Although the scope of this document is limited to medical devices, it specifies requirements and provides guidance that can be applicable to other products and equipment.

1.1.2 This document is intended to be applied by process developers, manufacturers of sterilization equipment, manufacturers of medical devices to be sterilized and the organizations with responsibility for sterilizing medical devices (see ISO 14937:2009, Table E.1).

1.2 Exclusions

1.2.1 This document does not specify requirements for the development, validation and routine control of a process for inactivating the causative agents of spongiform encephalopathies such as scrapie, bovine spongiform encephalopathy and Creutzfeldt-Jakob disease. Specific recommendations have been produced in particular countries for the processing of materials potentially contaminated with these agents.

NOTE See ISO 22442‑1, ISO 22442‑2 and ISO 22442‑3.

1.2.2 This document does not specify requirements for designating a medical device as "STERILE". Such requirements are given in EN 556‑1.

1.2.3 This document does not specify a quality management system for the control of all stages of production of medical devices.

NOTE It is not a requirement of this document to have a complete quality management system during manufacture or reprocessing, but those elements of such a system that are required are normatively referenced at appropriate places in the text. Attention is drawn to the standards for quality management systems (see ISO 13485) that control all stages of production or reprocessing of medical devices including the sterilization process. Further guidance is given in E.4 of ISO 14937:2009.

1.2.4 This document does not specify requirements for occupational safety associated with the design and operation of LTSF sterilization facilities.

NOTE 1 Safety requirements for sterilizers are specified in IEC 61010‑2‑040.

NOTE 2 Attention is also drawn to the existence in some countries of regulations stipulating safety requirements.

1.2.5 This document does not cover analytical methods for determining levels or residues of formaldehyde and/or its reaction products.

NOTE 1 Attention is drawn to EN 14180.

NOTE 2 Attention is drawn to the possible existence in some countries of statutory regulations specifying limits for the level of formaldehyde residues on medical devices and products.

1.2.6 This document does not cover preparatory measures that might be necessary before sterilization such as cleaning, disinfection and packing.

NOTE For reprocessable medical devices, the manufacturer(s) of these devices can supply information on the preparatory measures (see ISO 17664).