Sterility assurance means that repeated biological testing consistently produces negative results. |
The level of
disinfection-sterilization varies according to the appropriate use of the
item being disinfected or sterilized The longer the time the lower the probability of survival. The higher the temp-pressure the shorter the time to reach a specific level. It is the nature of water (suffciient in quantity) that in an enclosed container subjected to heat it will reach 15 Lbs psi at 250°F. If you know the temperature the pressure is known with or without a meter. If you know only the pressure the temperature is also known. Overkill is a term referring to the additional time a sterilizer operates beyond the time necessary to reach the kill level of sterilization. The common bio-reference is the bacterial spore G. Stearothermophilus which is used most often for biological monitoring of steam sterilization, which is usually in your BI that you use for biological testing. Normally two Biological Indicators (BIs) that bear the same lot control number are used. One is processed in the sterilizer and the other is not. The non-sterilized BI is called the control. Both are then cultured in an incubator.
If your sterilizer is
working properly the processed BI that you sterilized will not grow (usually
indicated by not changing color) and the unprocessed control BI will grow (usually
indicated by a change in color). Sterility assurance means repeated biological testing consistently produces negative results. |