HHM Compatibility Special Edition Feb/Mar 2020 HHM Compatibility Special Edition Feb:Mar 2020 | Page 10

probably within a week we had a situation where the syringe
clamp on the syringe pump broke off entirely. This machine
was pushing morphine, and because the syringe size was
wrong, the pump thought it had to push twice as far to
get the same amount of medication out, so it was double
the dose. The patient was severely over sedated but luckily
it was caught in time to avoid serious harm.”
Fechter continues, “We started examining the other
pumps in our fleet and found that by that time pretty much
all of them had been destroyed. They were old and we
needed to buy new ones anyway, but that is not the way
to do it. I blame the disinfectant as much as the handling
of the pumps.”
In his work for UCSF’s Surgical Innovations Program,
Fechter has studied and developed a wide variety of medical
equipment, devices, test equipment and both electronic
and mechanical fabrication and prototyping. Following that
incident with the syringe pump, and as a natural extension
of his professional curiosity, he began to conduct some of
his own compatibility testing.
“It was most likely some of the first compatibility testing
ever done,” Fechter says. “My test method was crude; I
soaked pieces of pump housing in different cleaning chemical
formulations and then observed what happened. The parts
were already exhibiting cracks completely through the
thickness of the material in mere hours of immersion — it
was complete destruction, and one of the most incompatible
combinations you can think of. Stuff crumbled amazingly
fast right in front of my eyes, so there was no doubt in my
mind that the disinfectants were tough on the materials.”
The Quest for Standards
Compounding the issue is that currently, no industry
standard exists for evaluating surface compatibility with
disinfectants, leaving healthcare personnel without the
necessary tools or education to make optimal decisions
about which disinfectants to use. Additionally, when new
hospitals are being designed or existing facilities are being
remodeled, there is no real guidance on which surface
materials to incorporate that will withstand the rigors of
the healthcare environment. For biomedical engineers
and designers, material compatibility with disinfectants
is often an afterthought, but it should arguably be a
key part of the design process if the equipment requires
cleaning and disinfecting.
The Facility Guidelines Institute (FGI) promulgates
guidance that recommends minimum program, space,
functional program, patient handling, infection prevention,
architectural detail, and surface and furnishing needs for
clinical and support areas of hospitals, ambulatory care
facilities, rehabilitation facilities, and nursing and other
residential-care facilities. When it comes to surface material
selection, the FGI’s 2010 edition of the guidelines, provides
the following information in A1.2-3.2.1.5 Surface selection
characteristics and criteria: “Testing standards can verify
whether a product provides specific characteristics. When
selecting surfaces and furnishings, verification of third-party
independent testing is expected to ensure that surfaces
meet necessary code requirements. It is understood that in
certain areas of the healthcare facility it will not be possible
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to use product with all these characteristics; however, the
goal is to strive to choose products with as many of these
characteristics as possible.”
According to the FGI, preferred surface characteristics
(of the ideal product) include:
• Easy to maintain, repair and clean
• Does not support microbial growth
• Non-porous and smooth
• Durable
• Sustainable
• Low-VOC (no off-gassing)
• Cost-effective (initial and life-cycle cost-effectiveness)
• Has compatible substrate and materials for surface
assemblies
• Seamless
• Resilient, impact-resistant
There are more than 30 standards-setting agencies
in existence, yet there is still no single, widely accepted,
standard for the testing of materials for compatibility
with chemistries used for cleaning and disinfection in the
healthcare environment.
It is critical to use the right material for the proper
application, but without standardized testing, this continued
variability causes confusion and allows the current incom-
patibility epidemic to continue unchecked. The interaction
between the cleaner/disinfectant and the material is critical,
but most often, this is 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
Compatibility Special Edition February/March 2020 • www.healthcarehygienemagazine.com