Textile materials fire tests

Measurement of flame spread under external heat flux is necessary where the thermal radiation is likely to impinge on the textile materials, for example, the flooring material of the building or transport vehicles whose upper surfaces are heated by flames or hot gases, or both. The French test method, NF P 92-503 Bruleur Electrique or M test involves radiant panel for testing flame spread of flexible textile materials. This test method (flame spread under external heat flux) is the basis of that used by the FAA (Federal Aviation Administration) for assessing flammability of textile composites used in thermal/acoustic insulation materials (FAR 25.856 (a)) used in aircraft and has also been included by the EU for fire test approval of floorings such as prEN ISO 9239 and BS ISO 4589-1. 

Numerous tests covering flame retardancy and related matters are available. The requirements most often specified for fire resistance of a textile materials are that it must pass either Federal Specification Method 5903 or NFPA 701. 

To produce a textile material resistant to fire, these four qualitative factors have been tested ... 

Within ASTM, technical committees associated with plastics, electrical materials, textiles, protective clothing, thermal insulation, consumer products, detention and correctional facilities, and ships have developed tests that are often application tests that are of specific interest to the products involved. One fire test has spawned more application standards than any other, primarily because of its vast use in the United States ASTM E 84 (Steiner tunnel). Thus, NFPA 262, UL 1820, UL 1887, ASTM E 2231, ASTM E 2404, ASTM E 2573, ASTM E 2579, and ASTM E 2599 are all test methods and practices based on the Steiner tunnel test. In some cases, the base apparatus is being modified (although usually it is permissible to conduct the ASTM E 84 test in the apparatus of the other test, but it is often not permissible to conduct the other test in any apparatus complying with the ASTM E 84 apparatus). The other test method that has resulted in many application standards is the cone calorimeter the standards are ASTM D 5485, ASTM D 6113, ASTM E 1474, ASTM E 1740, and ASTM F 1550. 

ASTM D 6113 Standard Test Method for Using a Cone Calorimeter to Determine Fire-Test-Response Characteristics of Insulating Materials Contained in Electrical or Optical Fiber Cables ASTM D 6194 Standard Test Method for Glow Wire Ignition of Materials ASTM D 6413 Standard Test Method for Flame Resistance of Textiles (Vertical Test)... 

NFPA 701 Standard Methods of Fire Tests for Flame Propagation of Textiles and Films NFPA 703 Standard for Fire Retardant Impregnated Wood and Fire Retardant Coatings for Building Materials... 

For textile materials used as interior wall-coverings in U.K. buildings including railway carriages, where the fabric could be in a vertical orientation attached to the wall panel, measurement of rate of flame spread under external heat flux is one of the requirements. For such applications, the test method (BS 476 Part 7) essentially requires a vertically oriented specimen exposed to gas-fired radiant panel with incident heat flux of 32.5kW/m2 for lOmin. In addition, a pilot flame is applied at the bottom corner of the specimen for 1 min 30 s and rate of flame spread is measured. The same principle is used in the French test for carpets, NF P 92-506. 

Designing FR textiles for required level of performance for specific end uses requires an understanding of the end-use conditions and specific flammability performance standards. Textiles in different applications are used either as a single component (e.g., apparel, curtains, bedsheets, etc.) or a component of the composite structure (e.g., furniture). In the latter, components other than textile material and their lay-up will also influence the burning behavior of the whole structure. This section discusses different fiber and fabric types used for different applications, associated fire hazards, and most relevant flammability performance standards. In Section 24.2, testing standards were discussed, which are used for testing materials to comply with performance standards discussed briefly in this section and in detail elsewhere.11... 

It is sometimes convenient to refer to fire tests for plastics, rubbers, and textiles, and while tests exist that are specifically intended for individual materials, a large number of fire tests are intended for products. For example, the Motor Vehicle Safety Standard is intended for materials used inside motor vehicles irrespective of their type. Standards directories list a considerable number of fire tests for plastics and textiles but relatively few for rubber, although in practice a number of the plastics tests are used with rubbers. 

BS 476. Part lO [7] is a guide to principles and applications of fire testing as applied to materials, composite.s, and products used in building construction. The BS 476 scries of tests arc not dealt with in detail here, as they are not primarily intended for building products, which will include plastics and textile products. 

Reaction-to-fire tests determine the specified parameter and are applied to materials or products. As such they are not specific to plastics, rubbers, or textiles and have therefore been considered separately. 

The tendency of a material to spread a flame away from the fire source is critical to understand the potential fire hazard. Flame-spread tests may refer to organic polymers themselves or to materials in diverse applications (such as textiles or electrical insulation sleeving), or to whole structures... 

Haase has extensively reviewed the topic of fire resistant clothing standards and regulations, and Shaw also discussed the use of standards in the selection of protective clothing materials. Horrocks lists many standard test methods for flame resistant textile applications. 

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