STERILIZATION VALIDATIONS: Chemical Sterilization
Although Ethylene Oxide is the most commonly used chemical for sterilization of devices, other chemicals are also used, and novel methodologies are being developed.
Where is Chemical Sterilization Appropriate?
Chemical sterilization is typically used for devices that would be sensitive to the high heat used in steam sterilization, and for devices that may be damaged by irradiation (rubbers and plastics can become more brittle after irradiation.)
Often chemical sterilizers function by using low temperature, highly reactive gases that come into direct contact with the test article (often through a semi-porous membrane or package.) Liquids - for example, bleach - are also used for sterilization.
Considerations in Chemical Sterilization
A primary concern in using chemical sterilization is ensuring that the item to be sterilized is compatible with the sterilant. Some sterilants can be chemically damaging to certain materials; you may wish to consult with your materials manufacturer for more information.
Other concerns regarding chemical sterilization include the potential harm to humans exposed to the sterilization chemicals or residuals from the sterilization process. The sterilization process must be monitored to ensure the safety of workers performing the sterilization.
Chemical Use in Disinfection
For reusable devices (such as those used in hospitals) chemicals are often used for repeated disinfection after each use (disinfection is a different process from sterilization). The chemical(s) and procedure used must be validated. In this case it is important to perform a cleaning and disinfection validation.
Chemicals Used for Sterilization or Disinfection
- Ethylene Oxide
- Glutaraldehyde and Formaldehyde
- Hydrogen Peroxide
- Peracetic Acid