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Department of Oral Pathology, Radiology & Medicine
--- Sterilizer Monitoring Program Best Practices

Hints to prevent contamination of dry heat sterilization monitoring tests.

Temperatures exceeding that required for sterilization may occur during a dry heat sterilization cycle, and may indirectly result in contamination of a spore strip. This may occur if excessive heat scorches the glassine envelope in which the spore strip is packaged (causing it to become brittle and crack) or breaks down the glue that seals the envelope. Either kind of damage can allow skin or environmental bacteria to enter the envelope and contaminate the spore strip during handing and transport.

The following may help to prevent this:

1. Wrap the glassine envelope in a single layer of aluminum foil prior to sterilization.
This may not prevent scorching, but will help to protect from contamination during handling and transport.

2. Stabilize the position of the strip within the sterilizer by use of clip or hemostat placed at the edge of the glassine envelope.*
This may prevent scorching by preventing the strip from being moved too close to the heating element by air currents that occur during the sterilization cycle.

3. Be careful to NOT overload the sterilizer.
To more rapidly achieve the temperature optimal for sterilization, some units may first rise to a temperature far exceeding the optimal temperature. An overloaded unit will require a longer period of excessive heat to achieve the optimal sterilization temperature.

*Spore strips should always be tested outside an instrument package.

Thank you for using University of Iowa Sterilizer Monitoring.
If you have any questions please call us at 1-800-626-4692