This International Standard specifies requirements for the characterization of a liquid chemical sterilizing agent and for the development, validation, process control and monitoring of sterilization by liquid chemical sterilizing agents of single-use medical devices comprising, in whole or in part, materials of animal origin. This International Standard covers the control of risks arising from contamination with bacteria and fungi by application of a liquid chemical sterilization process. Risks associated with other microorganisms can be assessed using other methods (see Note 1). This International Standard is not applicable to material of human origin. This International Standard does not describe methods for the validation of the inactivation of viruses and transmissible spongiform encephalopathy (TSE) agents (see Note 2). This International Standard does not describe methods for validation of the inactivation or elimination of protozoa and parasites. The requirements for validation and routine control described in this International Standard are only applicable to the defined sterilization process of a medical device, which is performed after the manufacturing process, and do not take account of the lethal effects of other bioburden reduction steps (see Note 4). This International Standard does not specify tests to establish the effects of any chosen sterilization process upon the fitness for use of the medical device (see Note 5). This International Standard does not cover the level of residual sterilizing agent within medical devices (see Note 6). This International Standard does not describe a quality management system for the control of all stages of manufacture (see Note 7).