that potential harborage points will not
allow for biofilms to form and will not
contribute to product contamination.
The data from the postclean swabs
will help assess the effectiveness of the
cleaning method and the cleanability
of the equipment; a team may find that
sandwiched parts have become pitted or
rusted, and that cleaning cannot bring
the results within specifications and
parts must be repaired or replaced.
Disassembly is also a good time to
take notes and pictures of the equipment to document the observations and
begin drafting a cleaning procedure that
will ensure that the task is performed
as intended over time. The pictures will
also help compare the findings as the
frequency of PEC tasks is adjusted to
establish a baseline.
What Should the Swab Limit Be?
Typically, before cleaning, the count
should not exceed the finished product specification; for example, if the
swab taken before cleaning is analyzed
for aerobic plate count (APC) and the
product specification for APC is 10,000
CFU/g, the swab limit could be set at
10,000 CFU for the dirty part. However, if the same surface is analyzed for
APC and Listeria spp., and the result
of the swab is 8,000 CFU for APC and
positive for Listeria spp., you should
investigate the positive Listeria spp. and
increase the cleaning frequency. If it is
the first time the parts are disassembled,
to avoid receiving swab results that are
“too numerous to count,” the plant
should work with its laboratory to dilute
the swabs to obtain actual counts.
Maximizing PEC Efficiency
To optimize PEC efficiency, its
activities should be coordinated with
preventive maintenance. In all cases, the
plant should have a PEC frequency for
all its equipment. In some cases, a few
pieces of equipment might be scheduled
every week; in other cases, they will
be grouped to be completed during a
production shutdown. You may come
to the realization that minor equipment
modifications can make these proce-
dures more effective and efficient. For
example, a guard might have many bolts
to keep it in place and secure (Figure 3),
but it may not need that many and all
but one or two might be replaced with
lock-and-key slots (Figure 4).
Complex equipment modifications
will be part of continuous improvement
projects but should be documented to
ensure they are dealt with at the appropriate time. Some minor modifications
can be made using the plant budget,
whereas more expensive modifications
and/or equipment replacement will be
part of the capital appropriation plan.
Until then, you will need a robust PEC
program to manage the design gaps.
It’s important to be aware of potential
niches and have cleaning procedures
and frequencies to mitigate the risk until a permanent solution can be found.
As with any other programs, docu-
menting is important to demonstrate
what was done, when and by whom. As
mentioned earlier, the documentation
of the PEC activities will help establish
the baseline. Once the baseline is de-
fined, the documentation will provide
the record that demonstrates that the
activities were completed. Any devia-
tion found during the PEC activities
will also need to be documented and
correction or corrective action undertak-
en to prevent product contamination.
As the saying goes, “What gets
measured and reported gets done,” so
there should be a performance indicator, tracking completion of the periodic
tasks. Over time, the information will
be useful to establish the resource requirement, budget and replacement
parts that may be needed to ensure the
completion of the different activities as
per the schedule. Your PEC program
will also be a living program, where, depending on equipment modifications or
new equipment brought to your facility,
your program is adjusted to take care of
the new reality.
The same concept can be applied to
infrastructure cleaning. While floors and
drains are always cleaned at the same
time as the equipment, walls, ceilings,
overhead pipes and non-production
areas will be cleaned less frequently
but nevertheless will have an assigned
cleaning frequency. We refer to it as the
periodic infrastructure cleaning (PIC).
The frequency will also depend on a
number of factors that might be similar
to those for PEC, for example, to prevent microbial growth in a production
environment, prevent infestation and
prevent an explosion in rooms where
dust can accumulate, such as a flour silo
or sifting areas.
Implementing a PEC/PIC program
might seem like an overwhelming task.
However, by taking a strategic and proactive approach, establishing a plan will
not seem as daunting. Start with the
part of the process that is most likely
to impact product quality and safety,
and with the equipment that is most
likely to harbor bacteria or pests. This
approach is always less stressful than
reacting to and investigating a situation
where product is spoiled or presents a
food safety risk after it has entered commerce. n
Richard Brouillette is the food safety director at
Commercial Food Sanitation (CFS).
Timothy Steffensmeier is senior food safety
specialist at CFS.
Figure 3. Conveyor Guard with Bolts
Figure 4. Lock-and-Key Slot