5.1 This test method measures the level of heat transfer through the thermal barrier textile material within a specific period of time.

5.2 This test method is used to evaluate thermal barriers and determine if they are able to withstand impingement by an open flame.

5.2.1 This test method is used to evaluate heat transfer when thermal barrier textile materials are used in conjunction with materials that demonstrate any of the following behaviors when exposed to high heat:

5.3 This test method cannot be used in place of the full scale test method TB603 or 16 CFR 1633.

5.3.1 This test method can be used as part of a supplier quality assurance program.

5.4 This test method is not intended to be used in evaluating heat transfer of thermal barrier textile materials used in protective clothing.

5.5 This test method is not recommended for acceptance testing of commercial shipments, since information on interlaboratory precision is incomplete. In some cases the purchaser and the supplier shall agree to test a commercial shipment of one or more specific materials and establish their own interlaboratory precision and bias, and also agree on acceptability limits.

1.1 This test method covers the evaluation of heat transfer of textile materials which are used as thermal barriers when exposed to a calibrated convective and radiant energy heat source for 60 s.

1.1.1 This standard is used to determine if the heat transfer is sufficient to ignite flammable materials which are contiguous to the textile thermal barriers.

1.2 This standard is used as a means to differentiate textile materials.

1.3 This test method is not intended to measure the insulation properties of materials used in protective clothing.

1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

1.5 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.

1.6 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 and health practices and determine the applicability of regulatory limitations prior to use.