Peeling Back the Mystery: Sterilizers’ Perspective

Next on our list was to talk with sterilization companies. Our questions for this portion of the healthcare value chain were a bit different. Instead, we were interested in knowing does a double barrier system impact the sterilization process? Is it more restrictive? Are there certain watch outs that companies should keep in mind when selecting between single or double?

What we found is in many cases the answer was that yes, the process is similar in a lot of ways but there are caveats. For example, the sterilization process is the same for single or double barrier but is a more challenging cycle for double barrier (EO specifically was the focus). This is because with a double barrier system, a deeper vacuum, longer cycle time, more nitrogen washes, and longer aeration time are required. A double barrier impacts the permeability of the EO gas both with intake and exhaust which then can affect the overall cycle.

If moving from a single barrier to a double barrier all validated EO cycles could require revalidation to address the complexity of a double barrier. To revalidate, usually involves significant cost and time. This could include revalidating product biocompatibility, especially for products with extended or long-term patient exposure.

If a double barrier is most appropriate for your product, they recommend keeping the following in mind:

• Your secondary packaging barrier (breathable layer) should be equal to and larger than the internal primary packaging barrier. Why? This reduces the potential for uneven pressure across both barriers as the vacuum is being pulled. Any significant variation in this pressure differential creates potential risk to the packaging “ballooning” and stressing the seals for the overall packaging system.
• If placed in both the primary and secondary barriers, Biological Indicators (BI) can be used to prove sterility effectiveness of the dual barrier systems.
• Any increase in EO residual as compared to the existing validated process may require revalidation and biocompatibility testing.