Significance and Use
4.1 Overview:
4.1.1 Assurance of product quality is derived from careful attention to many factors but is not limited to raw material acceptance, software workflow definition, product and process design and control, printing and post processing, equipment and systems installation, maintenance, and in-process and end-product testing.
4.1.2 By managing these factors, a manufacturer can establish confidence that all finished manufactured units from successive lots will be acceptable and meet lot release criteria.
4.1.3 The basic principles of quality assurance (QA) have as their goal the production of articles that are fit for their intended use. These principles may be stated as:
4.1.3.1 Quality, safety, and effectiveness shall be designed and built into the product as well as the production process.
4.1.3.2 AM product characteristics all cannot currently be verified after the process without destructive testing and therefore requires validation. Suitable consideration should be designed into the product and controls should be applied to the process during process validation.
4.1.3.3 Critical steps of the production process impacting quality shall be controlled to maximize the probability that the finished product meets all quality and design specifications.
4.1.4 Process validation is a key element in ensuring that these QA goals are met. Routine end-product testing alone is often not sufficient to assure product quality. Some end-product tests have limited sensitivity. In some cases, destructive testing would be required to show that the manufacturing process is adequate, and in other situations, end-product testing does not reveal all variations that may occur in the product that may have an impact on device performance. However, successfully validating a process may reduce the dependence on intensive in-process and finished product testing. Note that, in most cases, end-product testing plays a major role in supporting QA goals, that is, validation and end-product testing are not mutually exclusive.
4.1.5 Key process variables should be monitored and documented using statistical process control where applicable. Analysis of the data collected from monitoring should establish the potential variability of process parameters for individual production runs to ensure that a process is within acceptable control limits and the equipment can consistently produce the product within specification.
4.2 Preliminary Considerations:
4.2.1 A manufacturer should evaluate all factors that affect product quality through appropriate documented process characterization.
4.2.2 Risk management and an analysis file shall be created in line with ISO 14971. These factors may vary considerably among different products, manufacturing technologies, and facilities. No single approach to process validation will be appropriate and complete in all cases; however, the following quality steps should be undertaken.
4.2.3 All pertinent aspects of the production processes that have an impact on device design (product’s end use) should be considered during process validation. These aspects include, but are not necessarily limited to, performance, reliability, and stability. Performance limits and variation should be established for each characteristic acceptance criteria and expressed in readily measurable terms. Once a product specification is defined it is important that any changes to it be made in accordance with documented change control procedures and the device history file.
Scope
1.1 This practice provides an overview of how to perform process validation for medical devices manufactured using PBF/LB/M. The topics that will be covered include machine qualifications, software used in the manufacturing process, the importance of design specification and verification on process validation, and raw materials.
1.2 This practice also provides recommendations for process characterization, risk management, additive manufacturing (AM) facility qualification, and process control as a prerequisite for qualification activity, including installation qualification/operational qualification/performance qualification (IQ/OQ/PQ).
1.3 The practice is primarily focused on non-device-specific AM system(s) validation. Additional information may be needed in reference to the performance of the actual device.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
