This test method is intended for the determination of the radiant heat performance value of a material, a combination of materials, or a comparison of different materials used in flame resistant clothing for workers exposed to radiant thermal hazards.

This test method evaluates a material’s heat transfer properties when exposed to a heat exposure at a constant value and systematically varied durations. Air movement at the face of the specimen and around the calorimeter can affect the measured heat transferred due to forced convective heat losses. Minimizing air movement around the specimen and test apparatus will aid in the repeatability of the results.

This test method accounts for the thermal energy contained in the exposed test specimen after the radiant heat exposure has ceased. Higher values of Radiant Heat Performance rating determined in this test associate to higher values of radiant energy protection against a predicted skin burn injury.

This test method maintains the specimen in a static, vertical position and does not involve movement except that resulting from the exposure procedure.

This test method specifies two standard sets of exposure conditions, 21 kW/m² (0.5 cal/cm²s) and 84 kW/m² (2.0 cal/cm²s). Either can be used.

5.5.1 If a different set of exposure conditions is used, it is likely that different results will be obtained.

5.5.2 The optional use of other conditions representative of the expected hazard, in addition to the standard set of exposure conditions, is permitted. However, the exposure conditions used must be reported with the results along with a determination of the exposure energy level stability.

1.1 This test method measures thermal protective characteristics of flame resistant textile materials subjected to a standardized radiant heat exposure relative to a predicted second-degree skin burn injury.

1.1.1 This test method is not applicable to textile materials that are not flame resistant.

Note 1—The determination of a textile material’s flame resistance shall be made prior to testing and done according to the applicable performance and/or specification standard for the textile material’s end-use.

1.1.2 This test method accounts for the thermal energy contained in an exposed test specimen after the standardized radiant heat exposure has ceased.

1.2 This test method is used to measure and describe the response of materials, products, or assemblies to heat 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.

1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound or other units that are commonly used for thermal testing.

1.4 This standard does not purport to address the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.