In
the Pharmaceutical, Biotech, Life Science, and Medical Device industries,
companies need to produce product and perform research in areas with a high
level of sterility. To do so, product manufacturing and testing occurs in
expensive cleanrooms. High amounts of
attention are given to maintaining the cleanroom environment and often require
personnel entering the cleanroom to undergo rigorous gowning procedures. However, transporting in supplies &
equipment into the environment brings forth added challenges. Spraying and wiping items in order to
disinfect them is the method commonly used, however this method is unreliable
and inefficient. Unsuccessful
disinfection often occurs due to human error, insufficient chemicals used,
inappropriate dwell time, or any number of other factors.
When determining if a chemical agent is appropriate,
there are several varieties; sporicides, disinfectants, sanitizers, and antiseptics. All have very different intended uses and may
or may not be appropriate for the application in mind. If a chemical agent is chosen based on the
application it is intended for, then one has to consider the necessary dwell
time. To illustrate the importance of
dwell time, an example can be given of the extensive dwell time of bleach being
over ten hours on a surface.
Even if the proper contact time was achieved and
personnel feel as though they are doing a good job, the manual procedure of
spraying and wiping poses risk of not reaching all areas of an item that may
harbor organisms. Areas are often not
considered, or not treated with appropriate attention which leaves
contamination still present.
However, another tool that can be used is
Ultraviolet light (UV-C). The major
advantage to UV-C disinfection is the efficacy and the minimal time it takes to
achieve that level of kill. It is a
fast, simple to use method that is capable of providing a 99% reduction of
spores within minutes without chemicals.
This allows for little concern over material side effects due to the
lack of dangerous residues needed to be wiped down or neutralized afterwards. UV-C kills everywhere that the light is
shining, meaning all exterior surfaces will achieve disinfection. The limiting factor is if objects are sitting
on a surface due to an inability to get 360 degrees of light exposure. However, materials such as a quartz glass
shelf placed within a UV-C chamber can alleviate that concern due to the
penetration capability quartz glass has in comparison to most other
materials. An example of a device that
complies with the needs of a cleanroom is the Flash-Thru UV-C disinfection pass-through. The chamber is installed within a wall to
allow for items coming into the cleanroom to be disinfected immediately prior
to entry. From the non-sterile side, one
of the two UV-C protective doors is opened, then the user places the item(s) on
the quartz glass shelf, assuring not to stack items, then the start button is
pressed. Depending on the target
organism, kill can be achieved even as little as 30 seconds. Once the lights cease, the opposite door located
on the cleanroom side can be opened and the item can be retrieved. This method of disinfection is appropriate
for many applications, but especially electronics that are entering the space
because it is very gentle and will get successful kill on items that would
normally not be disinfected appropriately, or could be harmed with use of a
chemical agent. Cellular phones, pagers,
tablets and computers are all examples of technology that would be pertinent to
treat in this manner.
To better illustrate the
inefficacy of spraying and wiping surfaces alone, Animal Resources Centre in
Australia performed various tests to better realize the inadequacies spraying
and wiping resulted in. In the testing
below, organism colony counts were measured at three separate intervals. Initial swabbing prior to any cleaning,
secondary swabbing after spraying and wiping, followed by a final colony count
after ultraviolet light was used in the space.
Completing the traditional cleaning eliminated many organisms, however
many were still present. The addition of
ultraviolet light eliminated almost all remaining organisms that were still in
the environment. This experiment shows
that ultraviolet light technology has the capacity to reach many areas that are
often missed by humans, and can do so in a highly effective manner.
