If you manufacture high value product, you should be concerned with cleanliness, contamination control, and reliability. Two new documents that are directed at the medical device community
provide sensible, practical guidance for all manufacturers of high value product.
Guidance for validation of cleaning processes
ASTM standard F3127-16: “Guide for Validating
Cleaning Processes Used During the Manufacture of
Medical Devices” is a gold mine of useful approaches and procedures. While the scope of this newly
published standard is limited to cleaning of single
use medical devices during manufacture and prior
to use, the document draws on knowledge from
other high-value product including semiconductors, electronics, cleaning for oxygen environments,
and aerospace. The comprehensive standard is a
guidance document for developing and validating a
cleaning process, not a step-by-step recipe.
The detailed validation flowchart in the guidance document is a useful, adaptable resource. The
approach encompasses the concept of “validation
readiness” through process understanding and documentation. It emphasizes the importance of cleaning
throughout the supply chain as opposed to depending
on final cleaning. It also includes the concept that validation is not a one-time only event and instead alludes
to ongoing validation and monitoring.1
The first decision point on the flowchart poses
the question, “Is the device designed for cleanability?” This brings up our all-important issue of
establishing communication between designers,
assemblers, and quality managers. It is essential to
achieve appropriate product safety and performance.
We sometimes quip that the first step is to tie design
engineers to a chair with duct tape and force them
to try to assemble and clean a prototype of their proposed design. In actuality, a kinder, more productive
approach to implementing the guidance document is
to set up a manufacturing team early on in product
development and to include design engineers.
The phrase “regulatory issues” tends to evoke
the FDA. However, there are other regulatory issues
— worker safety and environmental compliance.
The ASTM guide does not specifically address the
mechanism of achieving safety and environmental
compliance. Attendees at a recent program for critical cleaning in the life-sciences expressed frustration
over pronouncements about allowable chemicals
and activities voiced by their safety and environmental groups. Rather than avoidance, exclusion,
or analogous use of duct tape, we suggest that safety
and environmental professionals also be involved in
product development. With the correct engineering
controls, it is usually possible to implement cleaning processes that meet safety and environmental
requirements while assuring product/patient safety.
The guide is comprehensive. Other sections
include approaches and procedures for determining
the scope of contaminating materials, risk analysis, and developing limits of acceptable residue.
Considerable detail is provided regarding both
specific and non-specific analytical methods, in
approaches to selecting the appropriate techniques
for the application. The guide also recognizes the
importance of sampling techniques.
One layer at a time
Additive manufacturing (3D printing) is entering the mainstream of manufacturing. The FDA
has responded with an encompassing, interactive
approach. In May 2016, the FDA Center for Devices
and Radiological Health (CDRH) and Center for
Biologics Evaluation and Research (CBER) issued a
draft guidance document. 2
The FDA hosted a workshop in 2014 to explore
issues that might arise with medical devices manufactured by additive manufacturing. 3 The 2016 draft
guidance document builds on ideas and concerns
presented at this workshop.
What are some potential issues for cleaning and
contamination control? Design for cleanability is an
even greater concern with additive manufacturing.
Additive manufacturing enables the design of complex
shaped devices. Devices could be designed to contain
inner recesses that are difficult to access. Cleaning
and/or rinsing fluids need to access surfaces and be
New documents offer assistance to those in the medical