A Class 5 integrator that fails at the end of a cycle is a signal to stop and investigate, not a reason to reprocess and move on. In this illustrative example, a dental office in Ontario opened the chamber and found that the integrator in the centre of the load had not reached its endpoint. Here is how the team responded, step by step, and what the rejected load taught them about their sterilizer.
The office is not named and some details are simplified, but the sequence mirrors calls we take from clinics across Canada.
Quick Facts
- A failed integrator means the load cannot be verified as sterile; treat the items as unsterile.
- Contain and document before investigating; re-running without a cause hides the problem.
- A Class 5 integrator is the per-load screen, while the biological indicator — run on each day of use in Ontario — is the routine requirement.
- Confirm the fix with clean test cycles before the sterilizer returns to normal use.
What Happened That Morning
The load was ordinary: sterilization pouches and wrapped cassettes scheduled for the first patients of the day. The assistant had placed a Class 5 integrator in the pouch at the centre of the load and autoclave tape on each wrapped pack. The cycle ran to completion without alarms, yet the integrator colour stopped well short of its endpoint.
The First 30 Minutes: Contain and Document
The assistant logged the cycle number, saved the printed cycle record, and photographed the failed integrator next to its pouch. Every item stayed wrapped and moved to a clearly marked quarantine shelf, and the first patients were told their appointments would run late.
Documentation preserves evidence if a sterilizer fault surfaces later, and it forces the team to slow down. Offices that handle failures well are the ones that write things down before touching anything.
The Investigation: Ruling Things Out
Cycle record review
The printout showed normal temperature and exposure time with no interruptions. That ruled out a short cycle but said nothing about steam penetration, which is exactly why chemical monitoring exists.
Packaging and loading
Here the team found its first problem. Pouches had been laid flat and stacked two layers deep, paper against paper. Steam follows the path of least resistance, and a packed basket can hide a dead zone in the middle, precisely where the integrator had been placed.
Machine function
The sterilizer had passed its most recent service check, and a Bowie-Dick test on the next test cycle confirmed air removal. That pointed the investigation away from the machine and toward the load.
| Question asked | How they checked | What it showed |
|---|---|---|
| Did the cycle run correctly? | Printed cycle record | Normal time and temperature |
| Was the load arranged well? | Photo taken at load time | Pouches flat and packed too tightly |
| Was packaging intact? | Visual check of pouches and tape | No tears or seal faults |
| Could the machine remove air? | Bowie-Dick test cycle | Passed; machine cleared |
The Biological Indicator Follow-Up
The office already ran a biological indicator weekly — short of what the RCDSO now requires, which is a BI on each day a sterilizer is used. Rather than wait for the next scheduled test, they placed a 24-hour rapid readout biological indicator in the centre of a test load and ran the corrected cycle the same day.
The division of labour worked like this: the integrator answers fast for one load, while the biological indicator confirms that the sterilizer itself can kill spores. A positive result would have meant an immediate service call; this one came back negative.
The Root Cause and the Corrections
The cause was loading, not the machine. Flat, stacked pouches had blocked steam from sweeping through the centre of the basket. Pouches now stand on edge in a single layer with space between them, and no basket is filled past its rated capacity.
The office then ran three consecutive test cycles with an integrator in the most challenging position; all passed, and normal scheduling resumed.
What Changed Long-Term
A Class 5 integrator now goes into every load, positioned where steam arrives last, and the biological indicator now runs every operating day. Autoclave tape still seals every wrapped pack, and cycle logs are reviewed monthly.
Above all, the team agreed that a failed indicator is an investigation, never an inconvenience. That attitude is what turns a rejected load into a training win instead of a repeat incident.
Frequently Asked Questions
Does a failed integrator mean the instruments are contaminated?
Not automatically, but the load cannot be verified as sterile. Treat the items as unsterile, quarantine them, and reprocess only after a clean test confirms the fix.
Can chemical integrators replace the biological indicator?
No. An integrator is a fast per-load screen, while the spore test — daily in Ontario — is the routine requirement. The two answer different questions.
What should we do with items from the rejected load?
Keep them wrapped and quarantined, away from clean supplies. Once test cycles pass and the follow-up biological indicator is negative, reprocess the items normally.
How do we know the problem is actually fixed?
A documented cause, consecutive clean integrator results, and a negative biological indicator together give reasonable confidence. If any of those signals fails again, the next step is a service call rather than another test run.
Related reading: see the full sterilization monitoring hub for BI, spore testing and autoclave guides.
deep dive: understand SAL (10⁻⁶) in our sterilization assurance pillar article.
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