This document specifies requirements and gives guidance on the procedures in the preparation of samples and the selection of reference materials for medical device testing primarily in biological test systems primarily in accordance with one or more parts of the ISO 10993 series. Specifically, this document addresses the following: — test sample selection; — selection of representative portions from a medical device; — test sample preparation; — experimental controls; — selection of, and requirements for, reference materials; — preparation of extracts. This document is not applicable to live cells but can be relevant to the material or medical device components of combination products containing live cells. Extractions for chemical characterization are covered in ISO 10993-18. Clause 7, 8, 9, 10 [with the exception of 10.3.5 and 10.3.11 b)], and 11 can apply to extractions for chemical characterization. Information given in C.1 to C.4 can also be relevant.