Computer and field evaluations in support of the VDmax approach for selected sterilization doses greater than 25 kGy

Originally, the VD_max approach was developed to substantiate a selected sterilization dose of 25 kGy. Thereafter, computer and field evaluations demonstrated the value of the approach for substantiation of selected sterilization doses less than 25 kGy. Verification of the use of the approach for substantiation of sterilization doses in excess of 25 kGy is now needed.The results of the computer evaluations conducted on the VD_max approach with 35 challenge microbial populations at sterilization doses of 30 and 35 kGy generally gave outcomes consistent with those observed previously, namely, safe and unambiguous. Outcomes perceived as unsafe have been shown to be a peculiarity of the manner of assembling challenge microbial populations. Field evaluations involving substantiation of four selected sterilization doses greater than 25 kGy and associated sterilization dose auditing gave acceptable outcomes. The present findings further affirm the value and reliability of the VD_max approach.