ANSI/AAMI/ISO 10993-9 provides general principles for the systematic evaluation of the potential and observed biodegradation of medical devices and for the design and performance of biodegradation studies. Information obtained from these studies can be used in the biological evaluation described in the ISO 10993 series. Considers both non-resorbable and resorbable materials. Not applicable to: a) evaluation of degradation which occurs by purely mechanical processes; methodologies for the production of this type of degradation product are described in specific product standards, where available; b) leachable components which are not degradation products; c) medical devices or components that do not contact the patient's body directly or indirectly.