
REQUIREMENT BASED METHODS
IQ, OQ, PQ are requirement based methods that facilitate the validation of a process.
All products and processes need validation when verification cannot be identified in the process output by monitoring or measuring. These types of validations are performed to reduce production costs and ensure regulatory requirements are met.
Installation Qualification, Operation Qualification and Performance Qualification (IQ, OQ, PQ) are requirement-based methods that facilitate the validation of a process before it is placed within a target environment. In the medical community, the primary regulatory body is the FDA which requires all medical device manufacturers perform a detailed IQ, OQ, PQ validation to fully verify each process.
IQ validation ensures that the facility and all equipment used to manufacture, measure and test the product is installed, maintained and calibrated as required. Additionally, this validation provides the opportunity to benchmark specific installation and process conditions over the life of the molding program. For example, if a process is not yielding the same dimensional stability after multiple runs, the problem could be attributed to water flow, different styles of nozzles or tips, or the use of different equipment. These deviations can contribute to process and dimensional variation as well as part instability. Documenting the initial installation settings allows for quick identification of the root cause of rejects.
OQ validation verifies key performance
components of a product or process
without taking into consideration the
cumulative effects introduced within the
environment during testing. Through the
use of analytical processes, statistical/
dimensional evaluations, and engineering
studies, this validation can establish the
appropriate operating limits of varied
process parameters to meet requirements
of the end product.
A Process Failure Mode Effects Analysis
(PFMEA) is a tool used to identify the
potential failures in the process from
procurement of material to shipment
of product. Each potential failure is
assigned a Risk Priority Number (RPN)
which assists the molder to narrow in
on the problem areas of the process.
In addition to the high-risk variables, a
molder will also use the specifications
of the materials, molding press
characteristics, and part geometry to
choose the process parameters to vary
during OQ validation.
An OQ protocol outlines what will be
tested throughout the run - including the
number of samples. After completing
gate freeze and viscosity studies, the
different combinations of those
pre-determined parameters are tested
in a Design of Experiment (DOE) and
the parts are delivered to the Quality
Department assuming all cosmetics are
acceptable.
A complete First Article Inspection (FAI)
is an essential piece to OQ validation
and determines whether all aspects
of the tool are correct. A capability
study is also essential and performed
on all customer-identified critical to
functional dimensions. A common
target Cpk is 1.33 to ensure the process
yields repeatable parts from setup to
setup and is centered within the print
specification limits. If it is determined
that parts do not meet a Cpk of 1.33
or better, the molder may choose to
re-execute OQ validation by narrowing
the process parameters or revise the
IQ, OQ, PQ are requirement based methods
that facilitate the validation of a process.
print specifications to account for the
actual results of the molded parts.
PQ validation demonstrates that the
process is stable and dimensionally
capable and the molded part meets
the customer’s expectations.
Typically, PQ is accomplished by
running the defined process through
three separate runs. These runs
are a simulation of three separate
production runs with a shutdown
period between each run. If the PQ
is unsuccessful and the molded part
does not meet customer expectations,
the root cause needs to be evaluated
and the two parties must work
together to define and accept a
resolution.
Validation is a method of establishing
documented evidence that proves
a high degree of assurance that
the manufacturing process will
consistently yield a product of predetermined quality. The business
approach that integrates validation
touches many areas of a company. At
PTA Plastics, our commitment to the
process is essential to success.