Flame spread, flammability

For some non-fire retardant grades of polymers, fire retardancy characteristics might improve when a filler is incorporated into the formulation. Thus, for epoxy resins, the incorporation of minerals, glass fibre, silica or graphite all improve flame spread, flammability and LOI from the poor category for the virgin polymer to the good... 

Flame spread Flammability LOI Flame spread Flammability LOI... 

Flame spread flammability evaluates how far away from the ignition source a flame travels across a liquid or solid surface. The test is carried out in accordance with ASTM E162 [12]. Only flexible cellular foams are tested using a variant of the method ASTM D3675 [13]. 

Flammable fla-m3-b9l [L flammare to flame, set on fire, fr. flamma] (1813) adj. A substance that is easily ignited, burns intensely, or has a rapid rate of flame spread. Flammable and inflammable are identical in meaning, however, the prefix in indicates negative in many words and can cause confusion. Flammable, therefore, is the preferred term. According to I.C.C. Regulations, hquids are flammable if their... 

Flammable A combustible material that ignites very easily, burns intensely, or has a rapid rate of flame spread. Flammable is used in a general sense without reference to specific limits... 

Solutions of these fire retardant formulations are impregnated into wood under fliU cell pressure treatment to obtain dry chemical retentions of 65 to 95 kg/m this type of treatment greatly reduces flame-spread and afterglow. These effects are the result of changed thermal decomposition reactions that favor production of carbon dioxide and water (vapor) as opposed to more flammable components (55). Char oxidation (glowing or smoldering) is also inhibited. 

Increasing the surface area of a combustible solid enhances the ease of ignition. Hence dust burns more rapidly than the corresponding bulk solid combustion of dust layers can result in rapid flame spread by train firing . Solid particles less than about 10 pm in diameter settle slowly in air and comprise float dust (see p. 51 for settling velocities). Such particles behave, in some ways, similarly to gas and, if the solid is combustible, a flammable dust-air mixture can form within certain limits. Larger particles also take part, since there is a distribution of particle sizes, and ignition can result in a dust explosion. 

Examples A, closed cell thermal insulation with high fire retardency and low smoke generation (52,54) B, pigmented APN coatings in aluminum substrates with low flammability, low flame spread, and low smoke (55) C, APN insulation and cable jacketing (56) D, open cell APN comfort cushioning (57). (Photograph courtesy of the Firestone Tire... 

Fire hazard is a combination of several properties, including ignitability, flammability, flame spread, amount of heat released, rate of heat release, smoke obscuration and smoke toxicity. 

Fire safety in a particular scenario is improved by decreasing the corresponding level of fire risk or of fire hazard. Technical studies will, more commonly, address fire hazard assessment. Fire hazard is the result of a combination of several fire properties, including ignitability, flammability, flame spread, amount of heat released, rate of heat release, smoke obscuration and smoke toxicity. 

Fire hazard is associated with a variety of properties of a product in a particular scenario [1]. It is determined by a combination of factors, including product ignitability, flammability, amount of heat release on burning, rate at which this heat is released, flame spread, smoke production and smoke toxicity. 

Techniques have been developed for the quantification of fire propagation using FMRC s Small-Scale Flammability Apparatus (A,6) and the National Institute of Standards and Technology (NIST) Flame Spread Apparatus (j J ). In this study, the FMRC technique was used. Oxygen Index and its dependency on temperature was used by AMTL to examine the fire propagation behavior of small samples of FRC materials (J 2). 

Long Jr, R.T., An evaluation of the lateral ignition and flame spread test for material flammability assessment for micro-gravity environments, MS Thesis, Department of Fire Protection Engineering, University of Maryland, College Park, Maryland, 1998. 

Rapid flame spread. As we know, radiant preheating of a material can cause its surface temperature to approach its piloted ignition temperature. This causes a singularity in simple flame spread theory that physically means that a premixed mixture at its lower flammability limit occurs ahead of the surface flame. Hence, a rapid spread results in the order of 1 m/s. 

The inherent flammability and low melting point of sulfur impose some limitations of SC use. Flammability can be controlled to some extent by the use of additives, and it is fortunate that the DCPD types of additives used to improve the durability of SC also impart a degree of fire resistance. Sulfur concretes are in any case considerably less of a fire hazard than wood. Because of the low thermal conductivity, heat penetration is slow, and SC can survive short exposures to fire without serious damage. Sulfur concretes do not support combustion, and flame spread is essentially zero. 

In the ASTM E84 25-foot tunnel furnace test (34) for measuring flame spread of building materials, an igniting pilot flame is applied to the underside of a horizontally mounted specimen. The flame heats the combustible material to pyrolysis, and the flammable gases given off are ignited by the pilot flame. 

The UL 94 standard specihes bench-scale test methods to determine the acceptability of plastic materials for use in appliances or other devices with respect to flammability under controlled laboratory conditions. The test method that is used depends on the intended end-use of the material and its orientation in the device. The standard outlines two horizontal burning tests, three vertical burning tests, and a radiant panel flame spread test. The most commonly used test method described in the UL 94 standard is the 20-mm Vertical Burning Test V-0, V-l, or V-2. The method is also described in ASTM D 3801. A schematic of the test setup is shown in Figure 14.3. 

The purpose of bench-scale reaction-to-fire tests is to measure the flammability characteristics of materials, i.e., ease of ignition, flame spread propensity, heat release, and production of smoke and toxic combustion products. Some tests are designed to measure only one of these characteristics. Other tests are more sophisticated and can be used to measure several characteristics at the same time. 

Another study demonstrating the importance of conducting multiflux flammability tests was conducted by Panagiotou and Quintiere [33], Quintiere used modeling of flame-spread to show that a polymer system can be accurately characterized only if the flammability is measured over a range of heat fluxes ignition time, flame spread, and HRR need to be measured at various fluxes. 

The RCC measures /ign, smoke, CO, specific heat of combustion, mass loss rate, and a variety of other parameters which can help to determine the mechanisms affecting the material flammability. The RCC data is an excellent complement to MFFS data as the MFFS is a measure of the interaction of several of these parameters measured in the RCC. Comparison of the RCC and MFFS data shows the inverse relationship between MFFS and pHRR (Figure 16.17) the higher the pHRR the lower the MFFS. A more detailed explanation of flame spread and more specifically flame spread using the flooring radiation panel apparatus [37] can be found elsewhere [38],... 

ASTM E13 21 08, Standard Test Methodfor Determining Material Ignition and Flame Spread Properties, Fire and Flammability Standards, 2008. 

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