Stay up to date on everything that’s happening in the wonderful world of AM through our LinkedIn community.
What do certification bodies or notified bodies look out for when validating additive manufacturing processes? In the MedTech area, the focus is on personnel qualification and, in particular, the process chain. In its new whitepaper, TÜV SÜD outlines the state of the art and goes into the applicable standards. “We point out existing gaps and possible problems in the additive manufacturing of medical products and outline practicable approaches,” says Simon Schlagintweit, Lead Auditor Additive Manufacturing at TÜV SÜD. The publication explains the individual steps of process chain qualification and validation and deals with the post-processing of products. The target group of the white paper includes industry representatives, but also decision-makers in point-of-care diagnostics in areas such as research institutes and hospitals.
Before a device intended for use in a regulated sector such as the medtech industry can be 3D printed, the relevant requirements must be qualified, verified and validated. By validating their processes, companies ensure that their products meet the applicable requirements. To do this, all process parameters must be verified and adhered to. TÜV SÜD distinguishes between two validation stages, a conceptual and a practical phase. “The risk assessment is a central step in the concept phase,” explains Simon Schlagintweit. “It helps companies to avoid process failures and failures or contamination of components.” By mapping the process, this step identifies, evaluates and reduces risks and relies on established tools such as the Failure Modes and Effects Analysis (FMEA), Ishikawa diagrams ( also known as herringbone diagrams) and fault tree analyzes. The practical phase includes the requirements related to installation qualification (IQ), operational qualification (OQ) and performance qualification (PQ).
The validation process evaluates the entire workflow according to ISO / ASTM 52920, the international standard for additive manufacturing. This standard for quality management systems (QMS) in additive manufacturing is based on the specification DIN SPEC 17071. In contrast, the applicability of the two AM standards ISO / ASTM 52904 and 52930 is limited; While ISO 52904 provides guidelines for the use of AM in critical applications, ISO 52930 outlines general qualification principles for AM devices. However, both standards only relate to one material class or production technology and are therefore not sufficient for a qualification.
Post-processing activities such as cleaning, sterilizing and packaging can have a decisive influence on the biological safety, surface quality and mechanical properties of products. Against this background, these activities are of crucial importance for the manufacture of medical devices. The test requirements vary depending on the individual device and application. Biological safety requirements are summarized in the ISO 10993 standard. The requirements for packaging and sterilization are specified in the ISO 11607 and EN 556 standards.
Although automation is advancing, the most important steps in additive manufacturing are still performed manually. Quality management systems (QMS) such as ISO 9001, ISO 9100 and ISO 13485 therefore require appropriately qualified personnel. This applies to areas such as quality inspection and development, but also to machine operators. Validation requires a team of experts with expertise from all areas of AM. “Competent personnel is the key to industrial-grade AM production facilities from MedTech. AM-specific roles must be defined and trained, ”emphasizes Simon Schlagintweit.