Smoke production, test methods

ASTM Annual Book of Standards. Standard test method for heat and visible smoke release rates for materials and products. Test Method E 906-83. American Society for Testing and Materials Philadelphia, PA, 1985. 

Tunnel Test. The tunnel test is widely used to test the flame spread potential of building products such as electrical cable (15) and wall coverings (16). The test apparatus consists of a tunnel 7.62 x 0.445 m x 0.305 m ia cross section, one end of which contains two gas burners. The total heat suppHed by the burners is 5.3 MJ/min. The test specimen (7.62 m x 50.8 cm), attached to the ceiling, is exposed to the gas flames for 10 minutes while the maximum flame spread, temperature, and smoke evolved are measured. The use of this and other flame spread test methods has been reviewed (17). 

Test Method for Heat and Visible Smoke Release Ratesfor Materials and Products, ASTM E906-83, ASTM, Philadelphia, Pa., 1983 (updated periodically). 

ASTM E 1354 Standard Test Method for Heat and Visible Smoke Release Rates for Materials and Products Using an Oxygen Consumption Calorimeter. Annual Book of Standards, Vol. 04.07, ASTM International, West Conshohocken, PA. 

ISO 5660-1 Reaction-to-Fire Tests—I leal Release, Smoke Production and Mass Loss Rate—Part 1 Heat Release Rate (Cone Calorimeter Method). International Organization for Standardization, Geneva, Switzerland. ISO 5660-2 Reaction-to-Fire Tests—I Ieat Release, Smoke Production and Mass Loss Rate—Part 2 Smoke Production Rate (Dynamic Measurement). International Organization for Standardization, Geneva, Switzerland. ISO 9705 Fire Tests—Reaction-to-Fire—Room Fire Test. International Organization for Standardization, Geneva, Switzerland. 

The range of toxicity test methods is bound to produce different fire conditions, and hence different toxic product yields. Four test methods (NBS Smoke Chamber, NF X 70-100, Fire Propagation Apparatus [FPA], and SSTF) have been compared, primarily from published data64 66 using the carbon monoxide yields and hydrocarbon yields (not recorded in the NFX tests), which are both fairly good indicators of fire condition, for four materials (LDPE, PS, PVC, and Nylon 6.6), at two fire conditions, well-ventilated and under-ventilated. The CO and hydrocarbon yields are shown in Figures 17.9 and 17.10. 

Despite the understanding that smoke obscuration ought to be measured in a large scale, or by a method which can predict large-scale smoke release, the most common small-scale test method for measuring smoke from burning products is the traditional smoke chamber in the vertical mode (ASTM E 662)39 (Figure 21.14). The test results are expressed in terms of a quantity called specific optical density, which is defined in the test standard. This test has now been shown to have some serious deficiencies. The most important problem is misrepresentation of the smoke... 

EN 50399, Common test methods for cables under fire conditions—Heat release and smoke production measurement on cables during flame spread test—Test apparatus, procedures, results, European Committee for Standardization, Brussels, Belgium. 

ASTM E 1354 Test Method For Heat And Visible Smoke Release Rates For Materials And Products Using An Oxygen Consumption Calorimeter, West Conshohocken, PA 2008. 

ISO 5660 Reaction-To-Fire Tests—Heat Release, Smoke Production And Mass Loss Rate—Part 1 Heat Release Rate (Cone Calorimeter Method), ISO, Geneva, Switzerland, 2002. 

Test Methods for Related Properties. Test methods are available to evaluate such related physical properties of retardants as smoke production, heat release rate, and toxicity. 

Basic Mechanisms. Finally, further work is necessary on fundamental mechanisms of individual fire retardants. These mechanisms are a function of the particular chemicals involved and the environmental conditions of the fire exposure. There is a need to establish common methods and conditions for determining these mechanisms in order to compare different treatments. This would give us a better understanding of how these compounds work in action and would provide a more efficient approach for formulating fire-retardant systems than a trial and error approach. Correlations also need to be established between rapid precise thermal analysis methods and standard combustion tests. Retardant formulations could be evaluated initially on smaller (research and development size) samples. The more promising treatments could be tested for flame-spread index, heat release rate, and toxic smoke production. 

Many test methods for the determination of the acute toxicity of combustion products from materials and products have been developed over the last two decades and continue to be developed and/or improved. In 1983, 13 of the methods published up to that time were evaluated by Arthur D. Little, Inc. to assess the feasibility of incorporating combustion toxicity requirements for building materials and finishes into the building codes of New York State. On the basis of seven different criteria, only two methods were found acceptable. These two methods were the flow-through smoke toxicity method developed at the University of Pittsburgh and the closed-system cup furnace smoke toxicity method developed at NIST (known at that time as the National Bureau of Standards (NBS)). Standard Reference Materials and protocols (SRM 1048 and SRM 1049) were developed at NIST and are available to the users of these methods to provide assurance that they are performing the methods correctly (see Relevant Websites ... 

Digestion of the products with different endonucleases, followed by agarose gel electrophoresis of the digested products, yielded specific restriction patterns that enabled direct visual identification of the species analyzed. This PCR-RFLP methodology allowed not only clear discrimination of different salmon species in raw and smoked products but also of different fish species that may be present in food products. Russell et al. (2000) demonstrated that this method can be used to differentiate between salmon species. The reliability and practicality of the method was also tested by a collaborative study carried out in five European laboratories (Hold et al., 2004). 

In contrast to the considerable number of fire tests for plastics, there are relatively few fire tests specifically for rubbers as such. There are a number of tests for rubber products including cable insulation, hoses of various types, and cellular products. In some cases, e.g.. cellular products, the test relates to both cellular plastics and rubbers, e.g.. BS 4735 and ISO 3582. Horizontal burning characteristics when subjected to a small flame or BS 5111. Determination of smoke generation. For convenience, these have been described in the section dealing with plastics tests, Other tests for rubber products include ISO 8030 [51], Flammability of rubber hoses for underground mining, ISO 3401 [52], Conveyor belts Flame retardation specification and test method, and BS 5173, Part 103 [53], Fire rc.sistance of plastics and rubber hoses and hose assemblies, and linings of hoses, etc. 

ISO 5660-1 2002, Reaction-to-fire tests Heat release, smoke production and mass loss rate Part 1 heat release rate (cone calorimetra method)... 

ASTM E2102-lla (standard test method for measurement of mass loss and ignitabihty for screening purposes using a conical radiant heater) and ISO 5660-1 2002 (reaction-to-fire tests-heat release, smoke producTion, and mass loss rate - part 1 heat release rate, cone calorimeter method) for mass loss. 

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