Silicone and Other Synthetic Rubber Standards for Medical Use

Silicone and other synthetic elastomers often serve as biomedical grade materials where they are fabricated into components and assembled as a medical device. A medical device communicates with the human body or in a broader sense, serves in healthcare related applications. Medical uses involve replacing biological structures or functions within the body; communicating by means of fluid transfer to and from the body; or acting as a shield or clean barrier to mitigate infectious transfer to the patient in general. Fabrication of medical device components imposes additional requirements of cleanliness and product testing beyond those commonly used in industrial manufacturing. By convention, medical regulations are written by application of use and period of human exposure. The Food and Drug Administration (FDA) recognizes practices for testing of medical devices by official consensuses. Recognized practices include standards written by the International Organization of Standards (ISO), United States Pharmacopeia (USP), and ASTM International. In the international arena regarding medical use, there is good agreement to the practices of the FDA with few exceptions. This paper will aid in navigating through the complexity in standards for medical use and help provide the material supplier and the fabricator of silicone and other synthetic elastomers a path to assess and validate materials and manufacturing methods for suitability. For the specification writer, a brief review of new trends in evaluating elastomers for medical use by means of in-vitro “cell culture” studies instead of using in-vivo “animal” testing will be highlighted. This trend is driven by the desire to reduce the unnecessary destruction of animals with negligible effect to human safety.