There are no tests
that exist which
can definitively
prove that a
medical device will
last 10 years unless
you have waited
10 years to see the
results, so screening
materials early by
exposing them to
drugs, disinfectants,
etc., will weed out
some that have a
lesser chance of
surviving 10 years
of service.”
not vetted adequately before the material
is manufactured into products for the
healthcare setting; only after the products
are in use is it discovered that they lack
robustness and durability.
“The lack of standardized testing is one
of the biggest issues I see,” says UCSF’s
Fechter. “Because testing procedures are
not standardized, everyone does it their
own way. When I conducted my own
super-cheap compatibility testing, I got
so-so results. I could identify incompatible
combinations, but I couldn’t necessarily
quantify any of it. There have been some
attempts at devising better testing
procedures, but, again, none of them are
the standards we need. That said, Eastman
Chemical Company is using one of the
best processes I have seen, which is an
impact test, which goes beyond merely
testing for tensile strength. In real life
what breaks equipment is impact, but I
think either of these tests would give you
a good idea of whether your materials
are going to be compatible. My testing
was non-quantitative, so all I had were
observations. I would stress the samples,
expose them to chemicals, and then look
for cracks, so it was a visual inspection — it
was a pass-fail kind of test. The only quantitative part of my
testing was that the incompatible combinations would break
faster. I would look at the samples every 24 hours each day,
and once the materials and parts broke faster, I assumed they
were less compatible than the ones that took longer to break.”
“Test methods are lacking, despite so many standards bodies,”
confirms Ellen Turner, global market development manager
for specialty plastics in medical devices at Eastman Chemical
Company. “As a result, you must ensure there are standard test
methods in manufacturing that say to the healthcare end user,
‘If you claim this is cleanable, show me what test method(s) you
used to prove it.’ The current testing methods don’t relate to the
failure mechanisms involved. And because there is not a high-level
entity calling for and monitoring standards and test methods, we
are not seeing robust-enough products in healthcare.”
“Facilities cannot accept this,” asserts Linda Lybert, founder
and executive director of the Healthcare Surfaces Institute, which
is addressing the compatibility issue head on through its education
and research programs. “Plenty of organizations, including ASTM
and ANSI, have created test methodologies that manufacturers
follow, but they aren’t evaluated further. In a literature review
conducted by the Healthcare Surfaces Institute, we found great
inconsistency in test methods to validate a product, as well as
a shocking lack of scientific data, and inconsistency in the type
of microorganisms used in the testing. I believe that surface
compatibility testing needs to be EPA-registered so hospitals
can select products and materials based on their performance.”
Lybert adds that their literature review revealed inconsistencies
in the definitions of the processes of cleaning and disinfecting.
“This means that when determining validation, manufacturers
weren’t considering the same definitions and criteria that should
have been standardized across the board and that they most likely
validated these variable methods and passed them down to the
end user. Many manufacturers use only a visual inspection to
tell if a product works; this is a BIFMA (Business and Institutional
Furniture Manufacturers Association) test method involving a
4-inch by 4-inch square piece of material that is looked at in
order to validate disinfectant damage to a textile. This is flawed,
because in the real world, the healthcare environment doesn’t
function as a single textile in an area of 16 square inches, and
the test only determines if the textile discolors, and that’s all.
Instead, manufacturers must look at a product as an assembly,
and the impact that the disinfectant has on the entire surface,
device or textile. Microphotography needs to be conducted
during the validation process, instead of looking at the material
on a macro level.”
Lybert says it would behoove industry to establish a standardized
test for equipment and device manufacturers as well
as disinfectant-makers who are united in the desire to improve
disinfectant chemistries to maintain efficacy against pathogens
while limiting damage to surfaces.
The tension continues between OEMs’ profitability by
continuing to sell products that may have not been validated
robustly enough, and their inherent desire to not harm patients
by producing good products. Less stringent rules protect profits,
but at what cost, ultimately?
“We are at a crucial crossroads,” Turner emphasizes. “Hospitals
can no longer afford to accept the status quo.”
As we have seen, currently, there is no standard that tells
healthcare end users that a product’s materials have been
screened before they are incorporated in materials before they
enter the healthcare environment. That is, the materials should
be determined to be cleanable and durable before they are
even incorporated into a manufactured product. This would be
beneficial for healthcare designers and architects, who often
choose materials based on aesthetics instead of performance.
“Not only is there significant discrepancy in test methodologies,
but materials are not being tested as assemblies,”
Lybert confirms. “Medical devices are tested as assemblies, as
required by the FDA, but there is still lingering confusion as to
what is required for surface materials. The issues of testing and
validation causes confusion in healthcare facilities because there
are no guidelines.”
Turner concurs. “We need better material-screening studies
and tests. Once materials are screened and selected, only then
is it appropriate to move into final product design and testing.
Currently, it’s a bit like the Wild West in manufacturing plants – there
is no good definition between the screening studies to select the
materials with which to design, then the final screening to see if a
product should be introduced into the hospital environment.” She
adds, “There are no tests that exist which can definitively prove
that a medical device will last 10 years unless you have waited 10
years to see the results, so screening materials early by exposing
them to drugs, disinfectants, etc., will weed out some that have
a lesser chance of surviving 10 years of service. The assembled
device must be tested as well, but if adequate screening has been
done, the chances of passing full assembly testing is much higher.
It will also reduce time to market if you choose the right materials
up front and don’t have to rework the design later after a failure.”
Order can be restored to this Wild West, and manufacturers
can become agents for change.
26 august 2020 • www.healthcarehygienemagazine.com