I understand that ISO 11607 addresses “worst case” in three separate areas.
11607-1 Clause 6.1.6 addresses the worst case device such as the largest, heaviest in a product family, or the device with the most fitments.
11607-1 Clause 6.3.4 addresses the worst case sbs at specified process limits of forming & sealing.
And 11607-2 Clause 5.1.5 addresses the worst case sbs configuration, such as the smallest & largest chevron pouches of the same materials.
Is there also a requirement to expose a packaging system to a “worst case” sterilization dose?
11607-1 clause 6.3.4 states, "Performance testing shall be conducted on the worst-case sterile barrier system produced at the specified process limits of forming and sealing and after exposure to all the specified sterilization processes.
NOTE Specified sterilization processes may include multiple exposures of the same or different sterilization
The guidance AAMI TIR 22Section G.6 states,
“The sterilization may be elevated to a worst case situation by performing multiple sterilization cycles.”
I interpret the use of the word “may” instead of “shall” in 6.3.4 and G.6 as meaning a worst case dose is not required.
For example a normal dose for products our company manufactures is 25-40kGy. Would this be acceptable prior to package performance testing per 11607-1 6.3, or would a “worst case” sterilization dose above 40kGy be required?
As mentioned in the question above, ISO 11607-1 clause 6.3.4 states, "Performance testing shall be conducted on the worst-case sterile barrier system produced at the specified process limits of forming and sealing and after exposure to all the specified sterilization processes.” The point being made about sterilization requirements is that they must be reflective of the worst case the sterile barrier system may ever see. For instance, could there be a situation where a product in its package is sterilized multiple times? (e.g. a packaged product that is placed in a kit and sterilized again, or a product that is run through a second time) or is there a possibility that in the specific sterilization cycle being employed dose mapping may cause some packaged devices to see higher exposures/temperatures than others?
TIR 22 suggests that multiple sterilization cycles “may” be used as a way of satisfying this requirement- this use of the word “may” does not mean the requirement does not have to be met, just that multiple cycles are one way of meeting it. In other instances, a device manufacturer may choose to sterilize at a higher dose, or for a longer time. It is completely dependent on the manufacturer’s assessment of what the product may see in its life cycle and the rationale the manufacture develops for illustrating that the worst case chosen is indeed reflective of the worst case the product will see.