5.1 This test method is used primarily to determine the heat evolved in, or contributed to, a fire involving products of the test material. Also included is a determination of the effective heat of combustion, mass loss rate, the time to sustained flaming, and smoke production. These properties are determined on small size specimens that are representative of those in the intended end use.

5.2 This test method is applicable to various categories of products and is not limited to representing a single fire scenario. Additional guidance for testing is given in X1.2.3 and X1.11.

5.3 This test method is not applicable to end-use products that do not have planar, or nearly planar, external surfaces.

FIG. 1 Overall View of Apparatus

Note 1: All dimensions are in millimetres.

Note 2: * Indicates a critical dimension.

FIG. 2 Cross-Section View Through the Heater

Note 1: All dimensions are in millimetres.

Note 2: * Indicates a critical dimension.

FIG. 3 Exploded View, Horizontal Orientation

FIG. 4 Exploded View, Vertical Orientation

FIG. 5 Exhaust System

Note 1: All dimensions are in millimetres (not to scale).

FIG. 6 Horizontal Specimen Holder

Note 1: All dimensions are in millimetres.

Note 2: * Indicates a critical dimension.

FIG. 7 Vertical Specimen Holder

Note 1: All dimensions are in millimetres except where noted.

Note 2: * Indicates a critical dimension.

FIG. 8 Optional Wire Grid (For Horizontal or Vertical Orientation)

Note 1: All dimensions are in millimetres.

FIG. 9 Gas Analyzer Instrumentation

Note 1: Rotameter is on outlet of the oxygen (O₂) analyzer.

FIG. 10 Smoke Obscuration Measuring System

FIG. 11 Calibration Burner

Note 1: All dimensions are in millimetres except where noted.

FIG. 12 Optional Retainer Frame for Horizontal Orientation Testing

Note 1: All dimensions are in millimetres.

Note 2: * Indicates a critical dimension.

1.1 This fire-test-response standard provides for measuring the response of materials exposed to controlled levels of radiant heating with or without an external ignitor.

1.2 This test method is used to determine the ignitability, heat release rates, mass loss rates, effective heat of combustion, and visible smoke development of materials and products.

1.3 The rate of heat release is determined by measurement of the oxygen consumption as determined by the oxygen concentration and the flow rate in the exhaust product stream. The effective heat of combustion is determined from a concomitant measurement of specimen mass loss rate, in combination with the heat release rate. Smoke development is measured by obscuration of light by the combustion product stream.

1.4 Specimens shall be exposed to initial test heat fluxes in the range of 0 kW/m² to 100 kW/m². External ignition, when used, shall be by electric spark. The value of the initial test heat flux and the use of external ignition are to be as specified in the relevant material or performance standard (see X1.2). The normal specimen testing orientation is horizontal, independent of whether the end-use application involves a horizontal or a vertical orientation. The apparatus also contains provisions for vertical orientation testing; this is used for exploratory or diagnostic studies only.

1.5 Ignitability is determined as a measurement of time from initial exposure to time of sustained flaming.

1.6 This test method has been developed for use for material and product evaluations, mathematical modeling, design purposes, or development and research. Examples of material specimens include portions of an end-use product or the various components used in the end-use product.

1.7 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.8 This standard is used to measure and describe the response of materials, products, or assemblies to heat and flame under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products, or assemblies under actual fire conditions.

1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 7.

1.10 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these tests.

1.11 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.