Production and bottling machines in the pharmaceutical industry, but also
plants for producing different kinds of food are more and more frequently
flushed through with aggressive cleaning agents. These cleaning and
sterilisation procedures, which can be carried out without the
work-intensive dismantling of the machines, are called cleaning in place
(CIP) and sterilisation in place (SIP). Unfortunately, by far not all of the
elastomer seal materials withstand the CIP and SIP media, which can sometimes have a
destructive effect. When in contact with these cleaning agents, some seal materials swell up and then extrude into the gap; others are in
fact destroyed.
In search of a universal material that remains uninfluenced by most of
the very aggressive CIP and SIP media, large series of tests have been carried
out, the results of which may even surprise experts. Especially as certain
seal materials are expressly recommended for the use in CIP processes
by relevant guidelines, e.g. DIN standards, however in the test they
proved to be unsuitable.
Another group of materials withstand excellently a specific class of
CIP media, but when exposed to other cleaning agents their robustness
turns out to be very poor. There was a single material from the group of
perfluor elastomers that showed itself to be outstandingly resistant to
all current CIP media.
A second material, EPDM 2, also got very good marks and showed only
deficiencies in the presence of an injection medium on the basis of
hydrogen peroxid/tensids of 0.5% to 1%. You can see in the following table
which seal materials were tested and what the results were.
"FDA-compliant seal materials" is one of the topics with
which we will deal at our 4-day GMP
Education Course "Pharmaceutical
Engineering" in Copenhagen, Denmark, from 9-12 December 2002.
Source: Dr Burkhard Ledig, Busak+Shamban
