Sterilization of healthcare products – Radiation – Part 1, ANSI/AAMI/ISO 11137-1: 2006, states that all changes in product, its package, or the presentation of product for sterilization shall be assessed for its effect on the appropriateness of the sterilization process. While the referenced standard addresses healthcare products, the same conditions must be assessed for all products processed in a gamma irradiator, regardless of product type or use. Communicating proposed package changes to the sterilization provider in advance will help ensure an accurate processing and performance qualification plan is established, and changes are implemented in a cost effective manner.
Package Volume, Package Density, Carrier/tote Loading Specifications
Most commercial gamma irradiators utilize a carrier/tote with fixed internal dimensions to transport product through the irradiation process. The specific carrier/tote internal dimensions should be obtained from the respective processing facility, and must be considered prior to making changes to the package. This will ensure that the loading configuration or number of packages/units per carrier is not adversely affected by a change.
Validated Process – Performance Qualifications (PQ)
Routine product processing is performed in a validated system in order to ensure reliability and reproducibility of the process. Performance qualifications (PQ), referred to as dose mappings, are performed to identify the location and magnitude of the minimum and maximum delivered radiation dose, as well as the relationship between the two.
Product packaging factors that may impact the PQ process include package volume (outer package dimensions), package density (density = package weight / volume) and the package configuration (carrier/tote loading specification) within the irradiator. Changes to any of these factors that differ from the original PQ must be assessed to ensure
processing specifications are achieved.
Once the package loading configuration, package density and PQ dose mapping is completed, the results become part of the product routine processing specification or work instructions. These work instructions will be utilized by the sterilization provider to process future deliveries of the same product/package.
Why notify your sterilization provider in advance?
In order to deliver the required radiation dose, the sterilization provider must calculate an exposure or cycle time for the products being processed. The determination of the required cycle time is based upon the qualified product packaging dimensions that have been established and documented in the current processing specifications.