How to interpret the results of ethylene oxide sterilization biological monitoring?

Editor:启欣灭菌技术有限公司 │ Release Time:2021-05-28 

Interpretation judgment

After culture, the positive control has bacteria growth within 24 hours; if the monitoring sample is continuously cultured and observed for 5 days, all aseptic growth can be reported that the biological indicator culture is negative and the sterilization is qualified.

The positive control group has a positive result, the negative control group has a negative culture, and the test group has a negative culture. It is judged as qualified for sterilization. The positive control group is positive, the negative control group is negative in culture, and the test group is positive, then the sterilization is unqualified; at the same time, it should be further identified whether the positive bacteria in the test group are indicator bacteria or caused by contamination.


Biological monitoring method for ethylene oxide sterilization

Place the conventional biological test package in the most difficult part of the sterilizer (the central part of all the sterilization packages). After the sterilization cycle is completed, the biological test package should be taken out of the sterilized items immediately. The self-contained biological indicator is cultured in accordance with the product instructions. If the spore sheet is used, the spore sheet should be inoculated into a sterile test tube containing 5ML of Tryptone Soy Broth (TSB) under aseptic conditions. 36 Incubate for 48 hours at ℃±℃, observe the preliminary results, and continue to cultivate in the sterile growth tube until the 7th day. When testing, the culture medium is used as a negative control (the self-contained biological indicator does not need to be a negative control), and the culture medium added with the spore sheet is used as a positive control.