The gamma irradiation sterilization process must be validated to obtain a sterility assurance level of 10-6 (i.e. sterile claim). The most common validation method is VDmax25 according to ISO 11137-1: 2006 which requires the following steps:
- Bioburden determination on 30 devices (10 units x 3 different batches)
- Determination of the verification dose according to ISO 11137-2: 2013
- Irradiate 10 devices at level of verification dose
- Perform sterility tests
- Depending on results, the sterilization dose is substantiated or not