DIN EN ISO 11138-1:2017-07

Biological indicator systems are used for testing sterilizers and for assessing the performance of sterilization processes. Part 1 of the DIN EN ISO 11138 series of standards specifies the general requirements for the manufacture and performance of biological indicator systems. The requirements are supplemented by test methods for determining the resistance of biological indicator systems. These include test methods for determining the live germ count, the D-value and the growth inhibition by germ carriers and packaging. For the determination of the D-value, procedures according to the fraction-negative method (Holcomb-Spearman-Karber, Stumbo-Murphy-Cochran, limited Stumbo-Murphy-Cochran method), procedures according to the survival curve and for the determination of the survival/kill range have been included. At least two of these methods shall be used. In addition, the standard contains specifications for the information to be provided by the manufacturer. Specific requirements for biological indicator systems for use in certain sterilization processes can be found in the other parts of this series of standards. These include - sterilization processes using ethylene oxide, in which ethylene oxide is used both as a pure gas and in mixtures with other gases; - sterilization processes with moist heat (saturated steam process); - sterilization process with dry heat; - sterilization process with low temperature steam and formaldehyde. The test germs to be used for the respective sterilization methods, the specific requirements for the suspensions, the germ carriers, the primary packaging for the biological indicators and for resistance are specified. The specific conditions for the test procedure to determine resistance have also been specified. The resistometers to be used for carrying out these test methods are specified in ISO 18472. The International Standard has been prepared by ISO/TC 198 "Sterilization of health care products" in collaboration with CEN/TC 102 "Sterilizers for medical purposes" (secretariat: DIN). The responsible German committee is Working Committee NA 063-04-08 AA "Indikatoren" ("Indicators") at DIN Standards Committee Medicine (NAMed).