Ask the Editors
I am about to buy a new sterilizer. What is the difference between the traditional autoclave and the Class B autoclave?
Type B sterilizers, also called pre-vacuum steam sterilizers, are similar to gravity displacement autoclaves in that they use steam under pressure to sterilize contaminated items. They have a pump that creates a vacuum in the chamber to ensure air is removed from the sterilizing chamber before steam enters. The advantage is that there is faster and more thorough steam penetration throughout the entire load. In addition to shortening the required time for sterilization, Type B autoclaves address the issue of wet instrument packs at the end of the cycle by having a post-sterilization vacuum cycle that facilitates drying by removing steam at the end of the sterilization portion of the cycle. Two representative examples are the Lisa (A-Dec) and the recently marketed Bravo (SciCan) .