Jennifer Galvin and Khyati Vyas
DuPont Protection Solutions
Note: blog post not original
At the 2016 Annual PDA conference in San Antonia, TX a poster that examined the effects of gamma sterilization on cleanroom garments was presented. 70% of cleanroom contaminants are related to people. This statistic is true despite the use of cleanroom suits for all personnel operating in cleanrooms. Therefore, the assessment of these suits’ durability can greatly impact the sterility assurance of the products produced in these rooms.
The group from DuPont presented a study that reviewed the “wear and tear” of cleanroom garments – both disposable and non-disposable and their ability to perform appropriately. Most companies that perform cleanroom operations on a daily basis will purchase a cleaning service for their garments rather than using single use disposable garments. Reusable garments are often preferred, because they are less costly, more comfortable and environmental. The authors found that cleanroom workers shed large numbers of particles and bacteria. During aseptic processing activities sterile garments are required and any impact on their function is critical if you are not working within isolators. They considered several properties of sterile garments:
- Garment cleanliness and particle shedding
- The garment’s ability to contain contamination coming from the wearer
- Sterility for processes/products that require it
- Garment durability
The results recommend assessing life cycles of garments (disposable garments should not be used more than once). Garment physical properties are impacted with multiple sterilization cycles and these impacts are not always visible. They found that tear strength and particle filtration efficiency decreased while particle shedding increased as a function of increasing radiation exposure due to multiple sterilization (cleaning) cycles.
They recommend having a procedure in place that will evaluate the point at which reusable garments are being negatively impacted or when they reach their useful life especially if sterile processes are not enclosed in an isolator environment.
For more information about this study please contact Jennifer Galvin at DuPont Protection Solutions.