Expanded Isolator Testing Requirements
The CAN/ULC-S536:2019 update offers a more thorough, systematic approach to isolator testing. FSS inspection reports now include dedicated sections that:
- Describe the location and identification of each isolator within the system
- Document how isolators and devices interact across different fire separations
- Test whether isolated zones can operate independently
- Confirm whether the system resumes automatically once the fault is cleared and the system is reset.
- Document loop performance and control panel response under simulated fault conditions
This level of detail in the testing report allows both building owners and inspectors to quickly see how the system behaves under real-world failure scenarios – something that was difficult to predict under previous testing standards.
Improving Fire System Survivability
The main goal of expanding isolator testing protocols is to increase fire system survivability. If isolators are not effective, a single fault can disrupt the integrity of the entire fire alarm system and pose a significant safety risk to building occupants.
Luckily, with new, more detailed isolator testing, the Ontario Fire Code ensures that fire alarm systems continue functioning even during severe events.
What It Means for Property Owners
Because isolator testing is more detailed and data-driven than before, inspections will take longer to complete. Each isolator and its respective fire separation must be tested one by one, which involves temporarily simulating faults and confirming the system’s behavior. Once tested, the isolator behaviour must be thoroughly documented, which further contributes to extended inspection time.
When scheduling fire alarm inspection, make sure to allocate extra time for isolator testing – especially if you are managing a large building with numerous, widely distributed isolators.