Immediate Benefits of Real-Time
Real-time microbial monitoring provides instant information that leads to
Troy Tillman Sr.
TSI Inc. C ompanies producing medicines and biotech products are concerned with airborne microbial contamination. They need to ensure that products and people are kept safe. The traditional, accepted method to test for micro-
Root cause analysis
organisms at critical locations in a process is the use of active
air samplers or settling plates. Typically, 1-meter-cubed samples
are taken onto agar plates and sent to a lab for culturing. The
colony forming units (CFUs) results come back from the lab
after four to ten days. Only after this waiting period will end
users know whether the manufacturing environment was in
control. Recently, the commercialization of a technology based
on laser induced fluorescence (LIF) has made it possible to look
at airborne viable microbial counts in real time. The potential to
instantly respond to an airborne microbiological event when it
happens is exciting—and beneficial.
Results from active air samplers are important—they can
inform us that there has been a problem, possibly an excursion
of some kind, and also enable identification of the microor-
ganism to support a root cause investigation. However, they do
not tell us when the contamination happened, or the source
of the contamination. New LIF-based bio-detection products
can provide better insight into these unknowns by measuring
airborne viable particle counts and displaying this data in real-
time. The data can be viewed via a local display or integrated
directly into a facility monitoring system (FMS).
One quality assurance professional recently stated that their
company spends thousands of dollars each year looking for
root cause of microbial contaminations, with limited success.
Positioning air samplers or settle plates to narrow down the
source of airborne microbiological contamination is difficult
and time consuming. Even when using good scientific and
risk-based approaches, there is at least a four-day wait to
know the result. And, taking periodic samples simply does not
provide enough information to find root cause. But, with real-
time viable particle counters, time-resolved data can provide
valuable insights into root cause. An immediate notification
to presence of airborne viable particles means finding the
source could potentially take minutes instead of days or weeks.
Furthermore, the instrument sample probe can be attached to
sample tubing and is identical to ones used by standard optical
particle counters. The probe can be
configured to beep every time an air-
borne viable particle is detected, just
like a Geiger counter, enabling end
users to sniff out the exact location of
the contamination source.
Another example is contamination
that comes from workers, particularly
when they start a shift in a cleanroom.
By having data to support the impact
of gowning practices on cleanliness,
companies can provide enhanced
training programs. Once root causes
are identified, actions can be taken to
rectify the issue, be it training, ventilation, filtration, machine maintenance,
or facility adjustments.
Regulatory authorities are very interested in root cause investigations,
and what preventative and corrective
actions were taken to ensure the problem will not occur again. When real-time viable particle counters are integrated into a FMS software package, the
22 FACILITY MONITORING
Figure 1: Quality control utilizes alert and action limits for reactive and corrective activities. In Quality
assurance, attention is placed on trending data, process improvement, and preventative actions.