Materials flammability development, fire test

Uses of Fire Tests in Materials Flammability Development... 

Higher irradiation levels give better reproducibility, more clearly defined ignition, and shorter measurement times, but correspond to more developed fires. Thus particularly for flame-retarded polymers, a smaller irradiation level often corresponds better to the fire protection goals addressed. Cone calorimeter results for the HRR at small irradiances correspond to flammability tests such as LOI and UL 94, if a reasonable set of materials are compared and the behavior is not dominated by dripping effects. Thus different considerations govern the choice of external heat flux.76 77... 

Test specimens for burning rate data were 1.27 x 15.24 X 0.318 cm3. Descriptions of burning rate and other flammability characteristics developed from small-scale laboratory testing do not reflect hazards presented by these or any other materials under actual fire conditions. 

Fire testing and classification of building and other materials are based on certain flammability characteristics such as flame spread, ignition temperature, smoke development, non-combustibility, fire resistance, rate of heat release, oxygen index, etc. Some of them are briefly discussed in the following paragraphs [124-126]. 

The primary consensus-based organizations in the United States developing and maintaining fire and flammability test standards are ASTM International (previously the American Society for Testing and Materials) and the National Fire Protection Association (NFPA). Committee EOS on Fire Tests is the primary committee in ASTM that develops fire and flammability test standards (25). Several material- or product-oriented Committees have subcommittees that develop fire and flammability test standards as well. For example. Committee D20 on Plastics has a subcommittee on thermal properties (D20.30) that develops and maintains some fire and flammability test standards for plastics. The Fire Test Committee is responsible for all fire and flammability test standards that are used by any of the fire safety codes and standards published by NFPA. A number of test laboratories in the United States, such as Underwriters Laboratories and FM Global, have established a consensus process that meets the requirements of the American National Standards Institute (ANSI) so that they now can publish American National Standards. 

Because of its increased use in homes, buildings, appliances, automobiles, aircraft, and many other sectors of our lives, plastic materials have been under considerable pressure to perform satisfactorily in situations involving fire. A good deal of time and money has already been spent on research and in-depth study of the behavior of polymeric materials exposed to fire. Many new tests for preliminary screening of materials and simulating actual fire have been developed. Before getting into a detailed discussion about tests and testing procedures, it is necessary to understand polymers as they relate to flammability. 

The Fire Propagation Apparatus. The fire propagation apparatus was developed by FM Global Research (previously Factory Mutual Research Corp.). The test is described in ASTM E2058, Standard Test Methods for Measurement of Synthetic Polymer Material Flammability Using a Fire Propagation Apparatus... 

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