Dangers in Cleanroom Investigations: Lessons Learned

Our multi-part series about unfortunate events in the lab wraps up with some important take home messages

The cleanroom series is now complete. The first three parts discussed environmental monitoring (EM), water, and In-process microbial contamination events. The fourth event required data from all three sample sources to identify root cause. This final part covers lessons learned, highlighting key takeaways from each story within the series.

Although these may not be the exact same events or sources of contamination in your facility, these scenarios are all very relatable. What lessons can you learn from these events? How can you apply those lessons to your site?

Personnel as Root Cause

This series hits on this lesson a lot, be careful blaming employees. Repeat issues are systemic problems. Even if the recoveries are people source bugs, there could be practices in place that are causing employees to unintentionally shed their flora.

There are other “human” aspects to these events. All systems are created by people. Production supervisors set up gowning flow. Mechanical Engineers created the water and product piping. Process engineers created the hose cleaning process. However, those personnel aren’t normally called out in root cause conclusions. Maybe that’s because they hold advanced degrees and have more experience in the industry. They also tend to be tenured and hold management positions at the site. That shields them and the systems they design from scrutiny. Don’t be afraid to put those systems under the microscope!

Trending and Identifications

Trending is essential for root cause investigations, and you don’t want to trend with blinders on. Open your trending program to compare areas with similar designs and expectations. If something feels like a trend, treat it like a trend. It seemed normal for gown-in rooms to have human source contamination until compared to gown-in rooms without those hits. Conversely, removing floor samples from the EM program significantly delayed remediation.

Go beyond colony counts with trending and include identifications . A low-level count from a cleaning validation sample was identified as Bacillus. This ID redirected root cause analysis for the product contamination event. Additionally, the comparison of closely related Pseudomonas recoveries shaped the understanding of multiple, but similar, contaminated hoses.

Be aware of what you can change

• This site couldn’t change ISO designations for the gowning rooms, but they found a way to minimize impact of not-fully-gowned personnel in the ISO 8 area.
• Validation engineers didn’t consider altering a validated tank cleaning cycle. That tune changed when a gap was found.
• The site didn’t have an easy way to sanitize hoses. That was the driving factor for not addressing them as root cause. The issue will continue until the site changes how the hoses are used or cleaned.

Good luck preventing these issues at your sites! Stay tuned to the Eureka blog for more individual contamination event stories.