Gas diffusion method

Overview
Gas diffusion refers to a sterilization method for heat, moisture or pressure sensitive items, with the exception of food, drugs or liquids. This method is reliable and economically feasible for smaller loads and is frequently seen in hospitals, veterinarian practices and medical device manufacturing practices where it is frequently used for non-autoclavable items.

Gas diffusion sterilization relies on the use of a bag containing an ampoule of liquid ethylene oxide (EtO) which, upon activation, evaporates and diffuses through the containing bag into a second bag containing the items to be sterilized. Once there, it sterilizes on contact given the proper temperature (50 degrees Celsius) and humidity.

The gas diffusion sterilization is a proprietary method developed by Andersen Products in 1958 and subsequently used by the Anprolene (EPA registered in 1968) and EOGas sterilizers.

Interchangeable names for this method are 'micro-dose sterilization" or "bag method" because of the use of a bag and the fact that it uses under 18g per sterilization load as opposed to the traditional use of tanks that weight several pounds in use by the conventional EtO sterilization chambers.