ISO/TC 194/WG 14 - Material characterization

This document provides a compilation of parameters and test methods that can be useful for the identification and evaluation of the physical, i.e. physico‑chemical, morphological and topographical (PMT) properties of materials in finished medical devices. Such an assessment is limited to those properties that are relevant to biological evaluation and the medical device's intended use (clinical application and duration of use) even if such properties overlap with clinical effectiveness. This document does neither address the identification or quantification of degradation products nor the evaluation of the physico-chemical properties of the degraded materials, which are covered in ISO 10993‑9, ISO 10993‑13, ISO 10993‑14 and ISO 10993‑15. Chemical characterization of materials is covered by ISO 10993‑18. The ISO 10993 series is not applicable when the material or device is not in contact with the body directly or indirectly.

This document specifies a framework for the identification, and if necessary, quantification of constituents of a medical device, allowing the identification of biological hazards and the estimation and control of biological risks from material constituents, using a generally stepwise approach to the chemical characterization which can include one or more of the following: — the identification of its materials of construction (medical device configuration); — the characterization of the materials of construction via the identification and quantification of their chemical constituents (material composition); — the characterization of the medical device for chemical substances that were introduced during manufacturing (e.g. mould release agents, process contaminants, sterilization residues); — the estimation (using laboratory extraction conditions) of the potential of the medical device, or its materials of construction, to release chemical substances under clinical use conditions (extractables); — the measurement of chemical substances released from a medical device under its clinical conditions of use (leachables). This document can also be used for chemical characterization (e.g. the identification and/or quantification) of degradation products. Information on other aspects of degradation assessment are covered in ISO 10993-9, ISO 10993-13, ISO 10993-14 and ISO 10993-15. The ISO 10993 series is applicable when the material or medical device has direct or indirect body contact (see ISO 10993-1 for categorization by nature of body contact). This document is intended for suppliers of materials and manufacturers of medical devices, to support a biological evaluation.

ISO/TS 10993-19:2006 provides a compilation of parameters and test methods that can be useful for the identification and evaluation of the physico-chemical, morphological and topographical (PMT) properties of materials in finished medical devices. Such an assessment is limited to those properties that are relevant to biological evaluation and the medical device's intended use (clinical application and duration of use) even if such properties overlap with clinical effectiveness.

ISO 10993-18:2005 describes a framework for the identification of a material and the identification and quantification of its chemical constituents. The chemical characterization information generated can be used for a range of important applications, for example, as part of an assessment of the overall biological safety of a medical device (ISO 10993-1 and 14971), as a measurement of the level of a leachable substance in a medical device in order to allow the assessment of compliance with the allowable limit derived for that substance from health based risk assessment (ISO 10993-17), for judging equivalence of a proposed material to a clinically established material, for judging equivalence of a final device to a prototype device to check the relevance of data on the latter to be used to support the assessment of the former, or for screening of potential new materials for suitability in a medical device for a proposed clinical application. ISO 10993-18:2005 does not address the identification or quantification of degradation products, which is covered in ISO 10993-9, ISO 10993-13, ISO 10993-14 and ISO 10993-15. The ISO 10993 series of standards is applicable when the material or device comes into contact with the body directly or indirectly (see 4.2.1 of ISO 10993-1). ISO 10993-18:2005 is intended for suppliers of materials and manufacturers of medical devices, when carrying out a biological safety assessment.