Alternative sample sizes for verification dose experiments and dose audits

ISO 11137 (1995), "Sterilization of Health Care Products-Requirements for V alidation and Routine Control-Radiation Sterilization", provides sampling p lans :For performing initial verification dose experiments and quarterly do se audits. Alternative sampling plans are presented which provide equivalen t protection. These sampling plans can significantly reduce the cost of tes ting. These alternative sampling plans have been included in a draft ISO Te chnical Report (type 2). This paper examines the rational behind the proposed alternative sampling p lans. The protection provided by the current verification and audit samplin g plans is first examined. Then methods for identifying equivalent plans ar e highlighted. Finally, methods for comparing the cost associated with the different plans are provided. This paper includes additional guidance for s electing between the original and alternative sampling plans not included i n the technical report. (C) 1999 Elsevier Science Ltd. All rights reserved.