1) Investigations: If conventional environmental monitoring methods show unexpected elevated levels of microbiological contamination,
or if media fill results in an aseptic area yield one or more positive vials, the IMD-A system would be a valuable tool to
immediately assess the environment. Assuming the microbiological contaminants were still present 5–7 days later (which is
not always the case), the IMD-A could help locate the contamination and ascertain its cause to facilitate corrective action.
The IMD-A can also check the effectiveness of corrective actions during investigations in real time before operations are
2) Reduction of shutdown time: Currently, conventional environmental monitoring methods verify that an area has returned
to its validated state after being shut down for repairs or renovations. Such environmental monitoring data determine when
to restart the operation. In an aseptic environment, they are used to determine when to perform media fills. The IMD-A could
supply information about the environment rapidly, reducing the risk of performing media fills before the environment has returned
to normal. In combination with conventional environmental monitoring and media fill data, the IMD-A could provide additional
information to collectively assess the risk of resuming operations faster than with competing methods.
3) Training: The IMD-A's ability to provide immediate feedback can be helpful to assess how an operator's movements in an
aseptic environment could affect the product. This feedback can provide information about whether or not an operator is ready
to be trained using conventional environmental monitoring data and media fills.
4) Modification of aseptic process: The IMD-A could also be used to determine how a change might affect the environment.
For example, if we want to change the way an intervention to clear a blockage in the fill line is performed, the IMD-A can
assess which method generates the least risk to the process, thereby reducing the risk of failure when the intervention is
performed in media fills before use in routine operations.
In the examples provided above, we have been careful to point out that the IMD-A can be used for additional information, but
that it is not the official system for environmental air monitoring. At Bayer, we are exploring the use of the IMD-A for these
purposes while pursuing additional studies and the question of what will it take to replace environmental monitoring of air
with the IMD-A. Answering this question promises the biggest future benefit—the ability to determine when an aseptic environment
is not performing acceptably and using real-time data to make immediate decisions about product manufacturing. We feel that
the IMD-A will have positive effects on our industry, helping us continue to provide safe and effective products.
Vishvesh K. Bhupathiraju,
PhD, is the manager of QC Microbiology at Bayer HealthCare, Berkeley, CA. At the same company, Brandon Varnau is QC director and can be contacted for more information about these studies at 510.705.7609, email@example.com
Jerry R. Nelson, PhD, is a specialist microbiologist at Nelson Laboratories, Salt Lake City, UT. J. P. Jiang is chief technology officer at BioVigilant Systems, Inc, Tucson, AZ. At the same company, Chuck Bolotin is the vice president of business development, marketing, and sales, and can be contacted for all questions related to BioVigilant
at 520.498.0427, firstname.lastname@example.org
The authors would like to acknowledge Shayna Zucker, Peter Nilsson, Jerry Ho, and Alan Chen for assistance with studies in
the cleanroom environment and Lisa Yonocruz for assistance with ScanRDI analysis. The authors would like to acknowledge Nelson
Laboratories and the US Army's Dugway Proving Ground for their microbial barrier test chambers and for their assistance during
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