When an IST product has been certified: IST Sterile, it is the standard or grade to which the product has been sterilised. This grade has been developed to suit customer requirements and new applications.
Although ‘sterile’ is an absolute term, the assurance that an item is sterile is a probability function. The Sterility Assurance
Level (SAL) of a product is defined as the probability of that item being non-sterile after exposure to a validated sterilising
process. Some materials are resistant to sterilisation, so we conduct tests and validation to ensure that the effects of sterilisation on some polymers and packaging materials are not detrimental to performance and shelf life.
It is essential to know the bioburden levels of incoming materials in order to determine the required sterilisation dose and the effect on packaging integrity and regular monitoring of any changes to these criteria. Regular bioburden testing is carried out on all IST seals. The results are logged & trended.
IST seals are Gamma Irradiated at a fully validated sterilisation facility, in accordance with ISO 13485:2003 and BS EN ISO1137-1-2006. The plant is fully validated to ensure that the parts are receiving the correct irradiation dose. Each batch is irradiated with a dose range of 25-35kGys of gamma. This is confirmed by a certificate of irradiation, together with the dose mapping audit, held on file at IST Scientific.