There are several different methods in use today for sterilization of medical equipment. Selecting the right method is a factor of the specific process, the type of device or equipment and even the types of microbial organisms that may be present.
Two of the most commonly used methods for sterilization of medical equipment and devices are the use of steam and the use of EO or ethylene oxide. Both can be very effective methods of microbial sterilization, but they are not equal in how they can be used.
Steam Sterilization
The process of steam sterilization is not the same as just exposing a medical device or instrument to steam. Instead, the steam is directed and it is at a set pressure as well as temperature to provide complete microbial sterilization. This process has been used since the late 1800s and is still used in many medical facilities on reusable medical equipment.
As the medical equipment or device has to be able to withstand high heat, pressure and moisture, this is not a good match for packaged items, electronics, or many plastics used in medical devices. However, this is a cheap and effective method of sterilization for metal and glass equipment.
EO Sterilization
In use since the mid-1950s, this is a five stage process that uses some humidification, exposure to ethylene oxide gas for specific time periods followed by evacuation of the gas from the chamber and air washes to remove residue.
This method can be used through packages, when electronic components are present, as well as with plastics and fabrics. This is also a method that can be used with devices comprised of a combination of materials.
The EO process offers full microbial sterilization. It is a higher cost option than steam, but it provides a wider range of sterilization processes for equipment that could not be processed by other methods.