Certified Surgical Technologist (CST) Practice Exam

What type of sterilization method is considered the minimum for surgical instruments?

1. Gas sterilization

2. Steam sterilization

3. Dry heat sterilization

4. Radiation sterilization

The correct answer is: Steam sterilization

Steam sterilization is considered the minimum method for sterilizing surgical instruments due to its effectiveness in killing a wide range of microorganisms, including bacteria, viruses, and spores. This method relies on the use of steam under pressure, which effectively penetrates materials and reaches high temperatures (typically 121 to 134 degrees Celsius). By maintaining these conditions for a specific duration, typically 15 to 30 minutes, instruments are rendered sterile. This method is widely accepted in surgical settings because it is not only effective but also efficient. Steam sterilization cycles can be completed relatively quickly compared to other methods, making it suitable for high-volume environments such as hospitals. Other methods of sterilization, while effective, may not be as universally applicable or practical for all types of surgical instruments. For instance, gas sterilization involves using ethylene oxide, which is suitable for heat-sensitive items but may leave residual chemicals that require additional aeration time. Dry heat sterilization requires longer exposure times and is primarily used for items that can withstand high temperatures, while radiation sterilization is typically reserved for single-use, pre-packaged items and not for general surgical instruments processed in a sterile processing department.