An explanation of common certifications for elastomeric components
The American Society of Mechanical Engineers (ASME) has periodically published standards for Bioprocessing Equipment, with the latest edition being published in 2016 (BPE-2016).1 These standards clearly recommend that only certain materials be used in bioprocessing. Use of 316L stainless steel is commonplace in bioprocessing. Ensuring that the correct stainless steel is used is a common practice and includes normal material certification as well a heat tracing of provided steel. For elastomers, the available choices and certifications are more numerous and often less well understood.
Acceptable elastomeric components are carefully chosen for superior durability and corrosion resistance. Recommended and common elastomers include including EPDM (ethylene propylene diene), FKM (fluoroelastomer) and FFKM (perfluoroelastomer). All of these materials, and several others, meet the necessary requirements. However, all of these elastomers are also available with a variety of certifications.
Elastomers that are used in conjunction with process fluids, or which are likely to come into contact with the process fluid, are recommended to carry a USP Class VI classification (indicating very low bioreactivity). USP VI classification is only common for materials that are used clinically and require a high degree of biocompatibility.2 This classification is only attainable for materials that pass stringent tests for toxicity and reaction to implanted materials during live animal testing. Holland applied technologies summarizes this process nicely.3
Another commonly used certification is “FDA approved” or “Food grade.” The US Department of Agriculture also has similar classifications. The US Food and Drug Administration (USFDA) maintains a list of materials that have been tested to be non-toxic and non-carcinogenic. The FDA does not specifically approve these materials – it is up to manufacturers to create materials from the established list and ensure that they pass the necessary testing. Many materials used in Bioprocessing will carry such an FDA certification. This is distinct from the USP VI classification. Manufacturers serving bioprocessors will often provide certifications for conformance to FDA 21CFR 177 and/or USP Class VI, especially for components that are likely to contact the final product. Again, Holland Applied Technologies has a great explanation of this process.4
Finally, the NSF/ANSI 51-2017 is also sometimes discussed. This is a set of standards for products used in the food and beverage industry and is suited to components and finished goods used in commercial food preparation. While some of the materials used in bioprocessing may carry this certification, this standard is not typically used when specifying components for bioprocessing.
While the various standards used in bioprocessing elastomers can be confusing, Alicat can help. We maintain a complete list of wetted materials and certifications for all of the flow instrumentation we provide, giving complete visibility into the materials used in construction. The BIO series controller and meters, for example, are specifically crafted to maximize compliance with BPE-2016.
1) ASME – STANDARDS – Bioprocessing Equipment – ASME.org, www.asme.org/products/codes-standards/bpe-2016-bioprocessing-equipment.
2) “United States Pharmacopeia.” Wikipedia, Wikimedia Foundation, 12 Aug. 2019, https://en.wikipedia.org/wiki/United_States_Pharmacopeia.
3) “What Is USP Class VI Testing and Why Is It Important.” Holland Applied Technologies, 14 Apr. 2014, https://hollandaptblog.com/2013/10/14/what-is-usp-class-vi-testing-and-why-is-it-important/.
4) “What Is the FDA and What Is an FDA Elastomer?” Holland Applied Technologies, 7 Oct. 2013, https://hollandaptblog.com/2013/10/07/what-is-the-fda-and-what-is-an-fda-elastomer-4/.