STERILIZATION BY IONIZING-RADIATIONS - DETERMINATION OF THE TREATMENT BY EXPERIMENTING FRACTIONAL DOSES

The sterilization of a product must lead to a safety level equal to 10-6, that is to say one chance to find a contamined element out of one million. This assurance of sterility cannot be achieved in radiosterilization by determining a sterilizing value linked to the bioburden, but by using an uniform treatment dose of 2.5 Mrads, recommended by the (Code of Practice of the International Atomic Energy Agency) in 1974, and by Pharmacopeia. A methodology leading to validate doses of radiations inferior to 2.5 Mrads would simultaneously reduce the costs of treatment and the alteration of the displayed materials. We suggest a process bringing the preliminary display of 3 samples of 50 items, to be sterilized under doses of radiation equal to 0.1 Mrad - 0.45 Mrad-0.95 Mrad. The statistical interpretation of the controls which have been carried out for 72 hours let us estimate the dose of treatment we need to get the prescribed safety level of 10-6. The determination by this method of the minimum intensity able to radiosterilize can be of major interest for the development of this process clean, continuous and without any residue, the classical sterility control of manufactured product turning useless in routine operation.