ULC ULC 135:2025 Standard Test Method for the Determination of Combustibility Parameters of Building Materials Using an Oxygen Consumption Calorimeter (Cone Calorimeter)

PREFACE

This is the Second Edition of the Standard Test Method for the Determination of Combustibility Parameters of Building Materials Using an Oxygen Consumption Calorimeter (Cone Calorimeter), ULC 135.

This Edition of the Standard has been formally approved by the ULC Standards Committee on Fire Tests.

Only metric SI units of measurement are used in this Standard. If a value for measurement is followed by a value in other units in parentheses, the second value may be approximate. The first stated value is the requirement.

Appendices A, B and C, identified as Informative, are for information purposes only.

In Canada, there are two official languages, English and French. All safety warnings must be in French and English. Attention is drawn to the possibility that some Canadian authorities may require additional markings and/or installation instructions to be in both official languages.

Attention is drawn to the possibility that some of the elements of this Canadian standard may be the subject of patents rights. ULC Standards shall not be held responsible for identifying any or all such patents rights.

Requests for interpretation of this Standard should be sent to ULC Standards. The requests should be worded in such a manner as to permit a “yes” or “no” answer based on the literal text of the requirement concerned.

The initiation of the review of this Standard will commence within 5 years of the date of publication, unless the Standard is identified as fitting within a stabilized category, whereby the review will commence within the appropriate time frame set out by ULC Standards.

Comments or proposals for revisions on any part of the Standard may be submitted at any time. Proposals should be submitted via a Proposal Request in the Collaborative Standards Development System (CSDS) at https://csds.ul.com.

This Standard is intended to be used for conformity assessment.

1 SCOPE

1.1 This test method determines combustibility parameters for the assessment of degree of combustibility of building materials by measuring the heat release and smoke production from specimens exposed to radiant heat using the test apparatus, specimen configurations and procedures described.

1.2 This test method determines the amount of heat and smoke that may be contributed to a fire involving products made from the same material as that of the test specimen.

1.3 This test method provides for radiant thermal exposure of a specimen. An external source of ignition is provided by an electric spark.

1.4 This test method is based on the observation that generally, the net heat of combustion of a material is directly related to the quantity of oxygen required for its combustion. This relationship is such that approximately 13.1 x 103 kJ of heat are released per 1.0 kg of oxygen consumed.

1.5 Heat release is measured from the moment the specimen is subjected to the radiant thermal exposure of a conical heater.

1.6 The primary measurements are oxygen concentration, light obscuration and exhaust flow rate. Provision is also made for measurement of mass-loss rate and time to sustained flaming.

1.7 Smoke development is measured by obscuration of light in the combustion product stream.

1.8 This test method is used to evaluate specimens in a horizontal orientation under an external heating flux exposure of 50 kW/m2. The specimen, once ignited, is also heated by its own flame.

Note: The test apparatus has provision for testing specimens in a vertical orientation. Discussion on such testing may be found in

Appendix C.