Study on the Test Method of D Value of Ethylene Oxide Detergent Biological Indicator

OBJECTIVE To research the test method for D value determination of ethylene oxide sterilization indicator. METHODS The D value of products from different companies were determined by limited Sperman-Karber (LSKP) method and proved by survival and killing time. The consistency of these two results indicated the validity of D value. If D value couldn't be proved by LSKP method, survival-curve method should be selected to examine D value. RESULTS Among the D value of the 5 samples, three of them using LSKP method could be validated by survival and killing time. The results of other two samples examined by survival-curve method were validated by survival and killing time successfully. CONCLUSION D value is the key technical parameter to evaluate the product quality of ethylene oxide sterilization biological indicator. The results of D value examined by LSKP method and survival-curve method show the difference. Survival and killing time is recommended to be applied in validation to assure the accuracy of D value.