Monitoring

No. The two categories of chemical indicators are single-parameter and multiparameter. A single-parameter chemical indicator provides information about only one sterilization parameter (e.g., time or temperature). Multiparameter chemical indicators are designed to react to two or more parameters (e.g., time and temperature or time, temperature, and the presence of steam) and can provide a more reliable indication that sterilization conditions have been met. Chemical indicators (no matter what class or type) do not verify sterility and do not replace the need for weekly spore testing.

The Food and Drug Administration (FDA) has determined that a risk of infection exists with these devices because of their potential failure to sterilize dental instruments and has required their commercial distribution to cease unless the manufacturer files a premarket approval application. If a bead sterilizer is used, dental health care personnel assume the risk of using a dental device FDA has deemed neither safe nor effective.

An air removal test is designed to detect inadequate air removal in pre-vacuum sterilizers. Air not removed from the sterilizer chamber prevents steam from contacting the items in a load and therefore interferes with sterilization. Follow manufacturer instructions for how to perform the test and frequency of testing. If a sterilizer fails the air removal test, the sterilizer should not be used until it passes inspection by sterilizer repair personnel.

A spore test should be used on each sterilizer at least weekly. Users should follow the manufacturer's directions for how to place the biological indicator in the sterilizer. A spore test should also be used for every load with an implantable device. Ideally, implantable items should not be used until they test negative.

If the mechanical (e.g., time, temperature, pressure) and chemical (internal or external) indicators suggest that the sterilizer is functioning properly, a single positive spore test result probably does not indicate sterilizer malfunction. Items other than implantable items do not necessarily need to be recalled. However, the sterilizer should be removed from service and sterilization operating procedures reviewed to determine whether operator error could be responsible. Sterilizer operators should repeat the spore test immediately using the same cycle that produced the positive spore test.

If the result of the repeat spore test is negative and operating procedures were correct, then the sterilizer can be returned to service. If the repeat spore test result is positive, do not use the sterilizer until it has been inspected or repaired and rechallenged with spore tests in three consecutive fully loaded chamber sterilization cycles. When possible, items from suspect loads dating back to the last negative spore test should be recalled, rewrapped, and resterilized. Results of biological monitoring and sterilization monitoring reports should be documented.

See Table 12[PDF-948K] of the Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 for the suggested protocol to manage a positive biological indicator in a steam sterilizer.

Common Causes of Sterilization Failure

Modified from Miller CH and Palenik CJ (2010).

For each sterilization cycle, record the type of sterilizer and cycle used; the load identification number; the load contents; the exposure parameters (e.g., time and temperature); the operator’s name or initials; and the results of mechanical, chemical, and biological monitoring.

Records of sterilization monitoring (mechanical, chemical, and biological) should be maintained long enough to comply with state and local regulations. The Centers for Disease Control and Prevention (CDC) does not maintain information on time limits for every state but provides an example of 3 years in its sterilization guidelines, which is the time frame used by the Joint Commission inspection agency.