ASTM E1995-21 PDF

SIGNIFICANCE AND USE 5.1 This test method provides a means for determining the specific optical density of the smoke generated by specimens of materials, products, or assemblies under the specified exposure conditions. Values determined by this test are specific to the specimen in the form and thickness tested and are not inherent fundamental properties of the material, product, or assembly tested. 5.2 This test method uses a photometric scale to measure smoke obscuration, which is similar to the optical density scale for human vision. The test method does not measure physiological aspects associated with vision. 5.3 At the present time no basis exists for predicting the smoke obscuration to be generated by the specimens upon exposure to heat or flame under any fire conditions other than those specified. Moreover, as with many smoke obscuration test methods, the correlation with measurements by other test methods has not been established. 5.4 The current smoke density chamber test, Test Method E662, is used by specifiers of floor coverings and in the rail transportation industries. The measurement of smoke obscuration is important to the researcher and the product development scientist. This test method, which incorporates improvements over Test Method E662, also will increase the usefulness of smoke obscuration measurements to the specifier and to product manufacturers. 5.4.1 The following are improvements offered by this test method over Test Method E662: the horizontal specimen orientation solves the problem of melting and flaming drips from vertically oriented specimens; the conical heat source provides a more uniform heat input; the heat input can be varied over a range of up to 50 kW/m2, rather than having a fixed value of 25 kW/m2; and, the (optional) load cell permits calculations to be made of mass optical density, which associates the smoke obscuration fire-test-response characteristic measured with the mass loss. 5.5 Limitations8: 5.5.1 The following behavi... SCOPE 1.1 This is a fire-test-response standard. 1.2 This test method provides a means of measuring smoke obscuration resulting from subjecting essentially flat materials, products, or assemblies (including surface finishes), not exceeding 25 mm (1 in.) in thickness, in a horizontal orientation, exposed to specified levels of thermal irradiance, from a conical heater, in the presence of a pilot flame, in a single closed chamber. Optional testing modes exclude the pilot flame. Note 1: The equipment used for this test method is technically equivalent to that used in ISO 5659-2 and in NFPA 270. 1.3 The principal fire-test-response characteristic obtained from this test method is the specific optical density of smoke from the specimens tested, which is obtained as a function of time, for a period of 10 min. 1.4 An optional fire-test-response characteristic measurable with this test method is the mass optical density (see Annex A1), which is the specific optical density of smoke divided by the mass lost by the specimens during the test. 1.5 The fire-test-response characteristics obtained from this test are specific to the specimen tested, in the form and thickness tested, and are not an inherent property of the material, product, or assembly. 1.6 This test method does not provide information on the fire performance of the test specimens under fire conditions other than those conditions specified in this test method. For limitations of this test method, see 5.5. 1.7 Use the SI system of units in referee decisions; see IEEE/ASTM SI-10. The inch-pound units given in parentheses are for information only. 1.8 This test method is used to measure and describe the response of materials, products, or assemblies to heat and flame under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products, or assemblies under actual fire conditi...