injection moldingProcess Validation new definition from the FDA is “the collection and evaluation of data, from the process design phase through production, which establishes evidence that a process is capable of consistently delivering quality products.”   This needs to be performed when the process is not fully verified by inspection or testing.   For injection molding of critical components, this detailed and successful process validation must be defined and approved after producing parts that consistently perform according to customer specifications before production can be begin. 

Before beginning process validation for injection molding, it is important to understand the manufacturing process and the product specifications.   Experimentation by changing process parameters to determine which process variables having more impact on the product as well as how far those process variables can be varied while still manufacturing product that is acceptable and meets customer specifications.    Also, a clear definition of product specifications must be determined using scientific units of measure and defined limits and include industry standards whenever possible. 

There are three elements in the process validation process that play critical role in the injection molding process which are IQ, OQ and PQ.  Each of these elements need to be approved before proceeding to the next element.

What is IQ (Installation Qualification)?

During the first stage, the process equipment, along with supporting and subsystems, are inspected to ensure they conform to the requirements of the manufacturer and are installed appropriately.   

A few factors that are given consideration during IQ include the installation conditions, design features of the equipment, the conditions of the given environment and any documents, illustrations or manuals provided by the supplier.

Once installation and design specifications are met which can repeatedly produce parts that will perform up to standard, the process validation can continue to OQ.

What is OQ (Operational Qualification)?

This stage tests the newly installed equipment to ensure it operates as expected, and gauges the conditions under which it will continue to do so.  Test runs will determine the highest, lowest and nominal operating processes by varying the pressures, temperatures, velocities and other factors from the initial process arrived at during IQ.

Factors considered during OQ include the process control limits, the raw material specifications, the requirements for handling the materials, training and the short term stability and capability.

If Operational Qualification is successful, it will validate that all aspects of the equipment perform as expected under various conditions.

What is PQ (Performance Qualification)?

During Performance Qualification, the equipment will be run several times.  Real manufacturing materials will be used and the equipment will be allowed to cool between each run, to verify that the injection molding process is capable of consistently producing quality products at a range of operating conditions, established during the OQ part of the process.

Considerations during PQ include long term stability and whether the products produced under the expected levels of operating conditions consistently perform to standards.

At each phase of the validation process, documents must be drawn up which detail inspection results, parameters settings and any deviations from the expected performance and the reasons for them.  Only after IQ, OQ and PQ have been successfully completed and documents are produced which verify the acceptability of every phase of the injection molding validation process, can production get underway. 

If nonconforming product was found during the OQ or PQ, investigate of the failure is done to determine the root cause.  This root cause is then fixed by appropriate means and the procedure is revised and repeated to the appropriate runs to demonstrate that conforming product will be produced. 

It is important to make sure when it comes to manufacturing medical devices your injection molder is ISO 13485:2003 certified and have personnel who understand and can implement the process validation protocols. 

Process validation and utilizing IQ, OQ and PQ is part of the incorporated requirements of Crescent Industries quality management system for injection molding.  To learn more about Crescent’s quality certifications, please click here.

Topics: Quality