Certification Board for Sterile Processing and Distribution (CBSPD) Sterile Processing Technician Practice Exam

Which of the following monitoring methods verifies that conditions within the load were adequate to kill bacterial spores?

1. Chemical Indicator

2. Mechanical Indicator

3. Biological Indicator

4. Process Indicator

The correct answer is: Biological Indicator

The ability to verify that the sterilization process achieved the necessary conditions to effectively kill bacterial spores is critical for ensuring the safety and efficacy of sterilized medical instruments. The use of a biological indicator is the most reliable method for this verification. A biological indicator contains viable spores of a highly resistant microorganism, often Bacillus stearothermophilus for steam sterilization or Bacillus subtilis for dry heat. After the sterilization cycle is completed, the biological indicator is incubated to monitor whether the spores survived the process. If the spores are killed, the sterilization cycle can be deemed effective. This process directly assesses the lethality of the sterilization conditions. In contrast, chemical indicators and mechanical indicators serve different purposes. Chemical indicators change color or state when exposed to certain process conditions, but they do not confirm the killing of spores; they merely indicate that some part of the sterilization process occurred. Mechanical indicators involve monitoring equipment parameters like temperature and pressure but do not provide any direct evidence about microbial viability. Process indicators are used to assess whether items have been through a sterilization cycle but also do not provide information about the microbial destruction. Using biological indicators is a best practice in the field of sterile processing, as they provide the most definitive evidence of