Sterility Assurance for Cleanroom Wipers

Procedures specified by the Association for the Advancement of Medical Instrumentation (AAMI) are used by Texwipe and some other wiper manufacturers to certify the sterility of sterile wipers. The tests assure that there is less than one chance in a million of having a viable particle on one of these sterile wipers when the package is first opened. In six of seven sets of wipers tested, the count distribution data supported the hypothesis that the bioburden (colony-forming units, cfu, per wiper) had a Poisson count distribution, which would come from having a uniform probability of finding a viable particle on each of the 30 wipers tested ion the set. No evidence was found for wipers in any set having a highly unusual level of bioburden.