Department of Oral Pathology, Radiology & Medicine
--- Sterilizer Monitoring Program Retesting Positve Tests

Retesting of positive tests

A positive biological indicator strip test signifies a possible sterilization process failure. Please see culture report to see which sterilizer had the positive test and which test date the failure occurred. The sterilizer should be retested promptly to ensure sterile instruments.

Please investigate your sterilizer to determine what conditions are causing test failure.

Testing Directions:

  1. Run test strip for a complete sterilization cycle.
  2. Complete Retest Submission Request form.
  3. Promptly return processed test strip and completed form.

Possible reasons for test failure:

  • The load was not processed (Sterilizer did not start, cycle did not run completely)
  • The exposure time was not appropriate for the load configuration (sterilizer was packed too tightly or contained too many packages, wet instruments in chemical vapor sterilizer)
  • The cycle or equipment failed (leaky seal, dirty sterilizer, electrical interruption)
  • The test strip was contaminated after sterilization (possible only with dry heat sterilizers, enclosed culture result will indicate if test was positive or contaminated)

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