1975 Volume 45 Issue 9 Pages 446-451
The effects of Ethylone oxide(E.O.)gas sterilization on blood tube and coil-type dializar containing B. subtilis spore-strips as the indicator of sterilization has been examined at various time of sterilization under constant condition of gas concentration (mixtur gas : 20%. of E.O. gas and 80%. of carbon dioxide), temperature(50℃), moisture (40% RH), and innert pressure(1kg/cm^2G). B. subtilis spores from the strips inserted into tube and coil set in opened bag were no growth after exposure of E.O. gas for 4 hours. When the bag was closed, however, the spore-strips were not sterilized by exposure of the gas for 4 hours, and they were able to grow at sterilization for 3 hours, For the growth of bacteria from spore-strips heart infusion and brain heart infusion broth were better than thioglycollate medium for sterile test. The procedure of spore-strip which contained constant number of spores to obtain the same results at sterilization test, also, have been examined, because some of spore-strips purchased have often seen no growth or the trend of hard to grow due to strips contained small number of spores. From the experiments concerning of relationship between spore dose and the influence of the exposur time of E.O. gas the number of spores per a strip was found to have 10^4 spores over in case of the spore-strip in used as indicator of gas sterilization.
