Building materials may play a minimal role in igniting a fire, but they significantly influence how quickly it spreads.
That’s why Canada enforces strict regulations requiring fire endurance tests, such as CAN/ULC-S101. Using fire-resistant materials is particularly crucial in large or tall buildings, where a fire can grow rapidly before all occupants have evacuated.
The CAN/ULC-S101 test measures the fire resistance of building materials, evaluating their ability to contain a fire and reduce the risk of structural collapse. Both the National Building Code of Canada (NBC) and the National Fire Code of Canada (NFC) mandate that building materials meet fire resistance ratings based on the size and purpose of the structure.
In this article, you’ll gain a deeper understanding of the CAN/ULC-S101 standard, the testing process, and why compliance is essential.
What Is CAN/ULC-S101?
CAN/ULC-S101 is the standard fire test method used to determine fire-resistant ratings (section 3.1.7 of the NBC) for building materials and assemblies.
This fire endurance test is the Canadian version of the ASTM E119 fire test used in the United States. It measures the duration for which building materials can contain a fire, retain their structural integrity, or exhibit both properties during a predetermined test exposure.
The standard covers both structural and non-structural assemblies, including floors, roofs, ceilings, columns, beams, girders, and other components used in Canadian construction. It’s commonly used in commercial, residential, and industrial building projects.
Key Elements of the CAN/ULC-S101 Test
The fire endurance test is designed to replicate real-world fire conditions, measuring how long building materials and assemblies can withstand the heat, flames, and smoke of a fire.
If a load-bearing structure is being tested, the CAN/ULC-S101 standard calls for an applied load to be placed on the test specimen. It’s critical that fire endurance testing is conducted by an accredited testing facility and the standard procedure is followed to ensure accuracy and reliability.
The fire endurance test is designed to evaluate the following three criteria.
Fire Resistance Rating
A fire-resistance rating is assigned based on the results of the fire endurance and hose stream tests. This rating indicates how well a building material will prevent the spread of fire and smoke.
It’s defined by the NBC as “the time in minutes or hours that a material or assembly of materials will withstand the passage of flame and the transmission of heat when exposed to fire under specified conditions of test and performance criteria, or as determined by extension or interpretation of information derived therefrom as prescribed.”
Fire resistance ratings are reported in minutes or hours. For example, if a material maintains structural integrity for 30 minutes, it will have a fire rating of 30 minutes.
NBC fire rating requirements vary based on many factors (defined in 3.2.2), including building area, building height, occupancy type, whether sprinklers are to be installed, the number of streets the building faces, and whether the construction is permitted to be combustible.
Temperature Thresholds
Temperature thresholds indicate the material’s ability to prevent the fire from spreading from the compartment of fire origin to an adjacent compartment. Thresholds apply to wall and floor assemblies.
According to the NBC, the assembly should prevent the average temperature measured on the unexposed surface of the wall or floor assembly from exceeding 140°C above its initial temperature and prevent the temperature rise on the unexposed surface at any individual point greater than 180°C.
Structural Integrity
Structural integrity indicates the ability of building materials to minimize the risk of collapse. This can include resisting high temperatures, maintaining integrity under heat stress, and slowing the spread of flames. It applies to all floor and roof assemblies, load-bearing wall assemblies, beams, and columns.
The assembly or structure shall sustain the applied load for the duration of the fire endurance test.
Why CAN/ULC-S101 Compliance Matters
In Canadian construction projects, fire and life safety are paramount, and compliance is non-negotiable. Failing to meet fire resistance requirements puts occupants at risk and exposes stakeholders to fines and legal liabilities.
The NFC establishes the minimum fire safety criteria, while the NBC specifies the required fire-resistance ratings for building components. Most construction projects require materials and/or assemblies to meet these fire-resistance ratings. To ensure compliance, building engineers and designers should select materials and assemblies tested to the CAN/ULC-S101 standard.
How Testing Is Conducted
The CAN/ULC-S101 standard calls for the use of a full-scale horizontal (14’ x 18’) or vertical (10’ x 10’) furnace. The furnace burn is controlled so that the temperature inside follows a specific set of temperatures over a specific time period (following the time-temperature curve below).
It’s critical that fire endurance testing is conducted by an accredited testing facility and the standard procedure is followed to ensure accuracy and reliability.
Steps in the CAN/ULC-S101 Testing Process
- Sample preparation: Carefully construct the specimen to accurately reflect the intended assembly and ensure it meets size guidelines.
- Test set-up: Install the specimen in the full-scale test furnace and attach thermocouples and other monitoring devices.
- Fire exposure: Start the standardized time-temperature curve within the furnace and ensure the prescribed temperature profile is used throughout the test.
- Identifying failure: Determine the critical failure point (excessive temperature rise, flame spread, or structural collapse).
- Post-test analysis: Use the recorded data to determine the fire resistance rating and prepare a report to be used for accreditation.
Partnering With a Reliable Testing Provider
When it comes to meeting the strict requirements of the National Building Code of Canada, fire resistance testing is not an area to compromise.
Choose a lab with the right credentials: accreditation, certification expertise, extensive experience with the CAN/ULC-S101 standard, quick turnaround times, and a track record of proven accuracy.
Having your products tested for compliance instills confidence in consumers, architects, and regulators alike. NGC Testing Services brings 55 years of experience as one of North America’s most comprehensive and fully accredited independent testing facilities.
With thousands of successful tests to ULC standards under our belt, we’re ready to help you meet your compliance needs. When you're ready to complete a fire endurance test with confidence, reach out to our team of experts.
