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Sterile U

Class 5 vs. Class 6 Cls   Do you know the difference?


Question:

Are Class 6 Chemical Indicators (CIs) better than Class 5 Chemical Integrators?

Answer:

No. There are 6 classes of CIs that are classified by how each product is used to monitor the steam sterilization cycle (see table below). It is important to keep in mind that these classifications are NOT ranked in order of importance or performance.

Class 1: Process Indicators

For use on the exterior of individual packs, peel pouches, containers, etc… to indicate exposure to the sterilization process


Class 2: Indicators for Specific Tests

For use in specific test procedures (i.e. Bowie-Dick Type Test)


Class 4: Multi-Variable Indicators

For use inside individual packs, peel pouches, containers, etc… Reacts to two or more of the critical variables of the sterilization process


Class 5: Integrating Indicators

For use inside individual packs, peel pouches, containers, etc… Reacts to all critical variables of the sterilization process and the Stated Values must be equivalent to or exceed BI performance requirements


Class 6: Emulating Indicators

For use inside individual packs, peel pouches, containers, etc… Reacts to all critical variables of the sterilization process for a specified sterilization cycle


Question: What are the differences between Class 5 and Class 6 CIs?
Answer:  

Class 5 Chemical Integrators react to the three critical variables of a steam sterilization cycle (time, temperature, and the presence of steam). In addition, their performance is required to correlate to a biological indicator (BI). As a result, Class 5 integrator results are similar to those of a BI and can detect failures where the selected temperature isn’t reached. This failure condition is likely to occur when there is incorrect packaging and loading, air/steam mixtures, and/or incorrect cycle for load contents.

In contrast, Class 6 CIs react to the three critical variables for a specified cycle, and their performance may or may not correlate to a BI. Class 6 CIs are sometimes referred to as cycle specific indicators. It is important to realize that if you run multiple exposure times and temperatures, you must use a distinct Class 6 CI to monitor each cycle time and temperature. And because Class 6 CIs are not required to correlate to a BI, a Class 6 indicator could reveal a pass where a BI would indicate a failure.