Biologic Sterilizer Monitoring

The Division of Oral and Maxillofacial Pathology provides a biologic sterilizer monitoring service. It involves monitoring heat sterilizers using a biologic indicator to test the effectiveness of the sterilizer in killing microbial life. It is the only true test of effective sterilization.

Subscribers to the service receive a year's supply of test forms, biologic indicator test strips, and control strips. The biologic indicators are filter paper strips impregnated with spores of Geobacillus stearothermophilus and Bacillus atrophaeus enclosed in a glassine envelope.

Throughout our 19 years of operation, we have performed more than 30,000 routine tests for subscribers. Sterilizers tested include autoclaves, chemiclaves, and dry heat sterilizers.


  • The biological indicator is placed in a typical sterilization load.
  • At the end of the sterilization cycle, the biologic indicator test and  an unprocessed control are mailed to the monitoring service for culturing.
  • Positive results, indicative of ineffective sterilization, are called into the office immediately and are verified by a gram stain.

What we offer

  • Biologic monitoring of autoclaves, chemiclaves, and dry heat sterilizers
  • Steam sterilization results in 24 hours
  • Quality assurance by an independent laboratory
  • Help with troubleshooting
  • Test results will be emailed directly to your office
  • Total confidentiality


Failed tests are repeated. If the retest is again positive, equipment malfunction is indicated and servicing followed by another test is recommended. If the first retest is negative, a load processing problem is indicated.

Routine biologic monitoring by subscribers has resulted in the early detection of sterilization failures, allowing corrective measures to be taken.

Contact information

Oral Pathology Lab
Dentistry Building, Dalhousie University
5981 University Avenue
PO Box 15000
Halifax, Nova Scotia, Canada
B3H 4R2
Tel: 902.494.3768
Fax: 902.494.6411

To subscribe to the service, please request a subscription form at