WEBCAST WRAP UP

The Sterilization Packaging Manufacturers Council (SPMC) is addressing questions presented during their February 2008 Webcast, “Understanding the Nuances of ISO 11607.” Visit the SPMC Web site at www.sterilizationpackaging.org or www.pmpnews.com for a complete list of questions and answers.

What is sheet separation?

Sheet separation is another term for delamination. This is applicable to laminated structures, where numerous folds in the laminated material may cause layers of the sheet to separate or delaminate. This can also occur in nonlaminated materials such as spunbonded polyolefins. For further information, you may consult Curt Larsen’s article, “Porous Sterile Barrier Integrity Testing: Failure Anomalies,” in the January 2006 issue of MD&DI (visit www.devicelink.com/mddi archives).

How do we establish the minimum seal strength for a given product? [Does a] standard explicitly state the minimum seal strength for a type of product?
There is no current U.S. regulatory standard that states the minimum seal strength for a given type of product. This is because product type is not the only determining factor in assessing seal-strength requirements. The mass and shape of the product may be the same, but there can be dramatic differences based on the sterilization protocol, protective packaging, distribution environment, and other factors that would render a guideline difficult, if not impossible, to create.

The seal-strength requirements can be determined through the design process for the packaging system. The first step in the design process is to determine the design inputs. These are the requirements and constraints that will guide the development process. Design inputs include the product design itself [and] package development, manufacturing, regulatory, marketing, sales, and the customer or end-user. In this process, you should be using the nine drivers that are listed in Annex D of AAMI TIR 22:2007: As always, the earlier you involve your packaging supplier in discussions, the greater your likelihood for success and the more efficient the material and package selection process will be. With the right inputs, your supplier should be able to guide you toward the right seal-strength requirements for your product.

How much porous area do I need for EtO sterilization?

The amount of porous area required can only be determined through validation efforts utilizing your unique sterilization process and your medical device. The density of the product to be sterilized, the pack-out configuration, and the sterilization cycle are all unique factors that determine the amount of porous area required for a package.

For example, you can begin with a package that has been processed successfully. Determine how different the package being designed is from that package and make a judgment on where to start sizing the porous area. After increasing or decreasing the porous area, run packages through the EtO cycle and determine whether the package remains intact and the product gets adequate sterilization.