Testing methods flame propagation

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... 

NFPA 701 2004 Standard Methods of fire tests for flame propagation of textiles and films. 

Some of the tests and criterion used to define fire resistance may be found in the Hterature (9). Additionally, the compression—ignition and hot manifold tests as defined in MIL-H-19457 and MIL-H-5606, respectively the Wick test as defined by Federal Standards 791, Method 352 flash point and fire point as defined in ASTM D92 autoignition temperature as defined in ASTM D2155 and linear flame propagation rate are defined in ASTM D5306 are used. 

The above flame retardants, HMPN and TMP, along with another commercially available alkyl phosphate, triethyl phosphate (TEP), were systematically characterized by Xu et al. To quantify the flammability of the electrolytes so that the effectiveness of these flame retardants could be compared on a more reliable basis, these authors modified a standard test UL 94 HB, intended for solid polymer samples, and measured the self-extinguishing time (SET) instead of the universally used flame propagation rate. Compared with the UL 94 HB, this new quantity is more appropriate for the evaluation of the electrolytes of low flammability, since the electrolytes that are determined to be retarded or nonflammable by this method all showed zero flame propa-... 

Flammability limits. The range of flammable vapor-air or gas-air mixtures between the upper and lower flammable limits. Flammability limits are usually expressed in volume percent. Flammability limits are affected by pressure, temperature, direction of flame propagation, oxygen content, type of inerts, and other factors. The precise values depend on the test method. 

ASTM C 1166-91 Standard Test Method for Flame Propagation of Dense and Cellular Elastomeric Gaskets And Accessories... 

Fire-test method development has followed two separate but complementary paths. One path, theoretically oriented, is characterized by the measuring of scientifically-meaningful fire properties, such as mass loss and rate-of-heat release. This approach also includes the development of mathematical models incorporating these properties to predict propagation and flame spread. A new lab-scale apparatus, the "cone calorimeter" developed at NIST is an example of the hardware now available to measure these fire properties. 

The higher the flame propagation rate, the faster the fire spreads and therefore the more flammable the fluid, as measured by the test. As can be seen this approach ranks the fluids in the same order as the flash point, with H-515 being the most flammable and H-537 the least. There are a variety of methods that can be used to demonstrate flammability and some show the PAO fluids in a better light than others however, the ultimate test of flammability has to be the performance of the fluid in service. US Air Force statistics show quite clearly a significant reduction in aircraft losses since the introduction of the PAO-based H-537 into service. 

The rate of flame propagation is usually referred to in the combustion of solids as well as of gases. In this case, it signifies an empirical value determined by a standardized test method for a specimen of definite shape under specified conditions. Alternatively the rate of burning can be characterized by the mass of the combustible material burnt in unit time, instead of the rate of flame propagation. 

If flame propagation by the material is poor. Method A may be applied to a specimen of 400 mmx40 mm on a frame of 530 mmx 100 mm. In this case, only a single marker is fixed 100 mm below the upper clip. After a similar ignition as for the larger specimen, none of the six specimens should burn up to the marker. Otherwise, the test must be repeated with the 1830x40 mm specimen. 

The flame spread index represents the resistance to fire propagation and decreases with increase in the resistance. The intent of the test method is to separate materials with higher Are propagation resistance from those with lower resistance and is not intended to predict the fire propagation behaviors of materials... 

In ASTM E648, Are propagates on the surface of the sample due to heat flux contributed by the leading edge of the flame and the radiant heater. With increasing distance, the radiant heat flux decreases, until the combined flame and radiant heat flux cannot satisfy the flame spread requirements and the flame is extinguished. This test method was developed as a result of need for flammability... 

Three test apparatuses and methods have been developed to determine the fire properties associated with flame propagation (1) the ASTM D 2863 oxygen index test method for downward flame propagation for small samples [14] (2) the ASTM E 1321-90 lateral ignition and flame spread (LIFT) test method for horizontal and lateral flame propagation... 

In the LIFT and FPI test methods, the following definition of the flame propagation velocity for thermally thick polymers is utilized [2,3,7,15] ... 

The heat of complete combustion is measured according to ASTM D 5865/ISO 1716 test methods [45,46]. The release rates of material vapors, heat, and various chemical compounds (including smoke) are measured according to ASTM E 906 (the Ohio State University Heat Release Rate, OSU-HRR, Apparatus), ASTM E 2058 (fire propagation apparatus) and ASTM E 1354/ISO 5660 (cone calorimeter) [45,46]. Smoke released in flaming and nonflaming fires of materials is also characterized... 

Flammable Limits the minimum and maximum concentrations of a flammable wipor or gas/air mixture that will propagate a flame (flash) when ignited.The currently accepted test method for determining flammability limits is ASTM E 681. Note lower flammable limit (LFL) and upper flammable limit (UFL) are often used interchangeably with lower explosive limit (LEL) and upper explosive limit (UFL)... 

As a results of the rapid increase in the fire model there is a great demand for the fire property and specialized test methods. New test methods have been developed such as [36] cone calorimeter, heat release measurements, etc. With these methods, the following fire properties have been measured for PO critical heat flux, thermal response parameter surface radiation loss, heat of gasification, flame heat flux limit, yield of products, heat of combustion, corrosion index, flame extinction index, fire propagation index, etc. [37]. 

The Standard for Tests for Flammability of Plastic Materials for Parts in Devices and Appliances (UL 94) has methods for determining whether a material will extinguish, or burn and propagate flame. The UL Standard for Polymeric Materials-ShortTerm Property Evaluations is a series of small-scale tests used as a basis for comparing the mechanical, electrical, thermal, and resistance-to-ignition characteristics of materials. 

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