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5.1 Uranium hexafluoride is a basic material used to prepare nuclear reactor fuel. To be suitable for this purpose, the material must meet the criteria for isotopic composition. This test method is designed to determine whether the material meets the requirements described in Specifications C787 and C996.5.2 ASTM Committee C-26 Safeguards Statement:5.2.1 The material (uranium hexafluoride) to which this test method applies is subject to the nuclear safeguards regulations governing its possession and use. The analytical procedure in this test method has been designated as technically acceptable for generating safeguards accountability data.5.2.2 When used in conjunction with appropriate certified reference materials (CRMs), this procedure can demonstrate traceability to the national measurement base. However, adherence to this procedure does not automatically guarantee regulatory acceptance of the regulatory safeguards measurements. It remains the sole responsibility of the user of this test method to ensure that its application to safeguards has the approval of the proper regulatory authorities.1.1 This test method covers the isotopic analysis of uranium hexafluoride (UF6) and may be used for the entire range of 235U isotopic compositions for which standards are available.1.2 This test method is applicable to the determination of the isotopic relationship between two UF6 samples. If the abundance of a specific isotope of one sample (the standard) is known, its abundance in the other can be determined. This test method is flexible in that the number of times a given material is admitted to the ion source may be adjusted to the minimum required for a specified precision level.1.3 The sensitivity with which differences between two materials can be detected depends on the measuring system used, but ratio-measuring devices can generally read ratio-of-mol ratio differences as small as 0.0001.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazards statements are given in Section 7.

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4.1 This practice is useful for assessing the source for an oil spill. Other less complex analytical procedures (Test Methods D3328, D3414, D3650, and D5037) may provide all of the necessary information for ascertaining an oil spill source; however, the use of a more complex analytical strategy may be necessary in certain difficult cases, particularly for significantly weathered oils. This practice provides the user with a means to this end.4.1.1 This practice presumes that a “screening” of possible suspect sources has already occurred using less intensive techniques. As a result, this practice focuses directly on the generation of data using preselected targeted compound classes. These targets are both petrogenic and pyrogenic and can constitute both major and minor fractions of petroleum oils; they were chosen in order to develop a practice that is universally applicable to petroleum oil identification in general and is also easy to handle and apply. This practice can accommodate light oils and cracked products (exclusive of gasoline) on the one hand, as well as residual oils on the other.4.1.2 This practice provides analytical characterizations of petroleum oils for comparison purposes. Certain classes of source-specific chemical compounds are targeted in this qualitative comparison; these target compounds are both unique descriptors of an oil and chemically resistant to environmental degradation. Spilled oil can be assessed in this way as being similar or different from potential source samples by the direct visual comparison of specific extracted ion chromatograms (EICs). In addition, other, more weathering-sensitive chemical compound classes can also be examined in order to crudely assess the degree of weathering undergone by an oil spill sample.4.2 This practice simply provides a means of making qualitative comparisons between petroleum samples; quantitation of the various chemical components is not addressed.1.1 This practice covers the use of gas chromatography and mass spectrometry to analyze and compare petroleum oil spills and suspected sources.1.2 The probable source for a spill can be ascertained by the examination of certain unique compound classes that also demonstrate the most weathering stability. To a greater or lesser degree, certain chemical classes can be anticipated to chemically alter in proportion to the weathering exposure time and severity, and subsequent analytical changes can be predicted. This practice recommends various classes to be analyzed and also provides a guide to expected weathering-induced analytical changes.1.3 This practice is applicable for moderately to severely degraded petroleum oils in the distillate range from diesel through Bunker C; it is also applicable for all crude oils with comparable distillation ranges. This practice may have limited applicability for some kerosenes, but it is not useful for gasolines.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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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 behavior during a test renders that test invalid: a specimen being displaced from the zone of controlled irradiance so as to touch the pilot burner or the pilot flame; extinction of the pilot flame (even for a short period of time) in the flaming mode; molten material overflowing the specimen holder; or, self-ignition in the nonflaming mode.5.5.2 As is usual in small-scale test methods, results obtained from this test method have proven to be affected by variations in specimen geometry, surface orientation, thickness (either overall or individual layer), mass, and composition.5.5.3 The results of the test apply only to the thickness of the specimen as tested. No simple mathematical formula exists to calculate the specific optical density of a specimen at a specimen thickness different from the thickness at which it was tested. The literature contains some information on a relationship between optical density and specimen thickness (1).95.5.4 Results obtained from this test method are affected by variations in the position of the specimen and radiometer relative to the radiant heat source, since the relative positioning affects the radiant heat flux (see also Appendix X2).5.5.5 The test results have proven sensitive to excessive accumulations of residue in the chamber, which serve as additional insulators, tending to reduce normally expected condensation of the aerosol, thereby raising the measured specific optical density (see 5.5.8.3 and 11.1.2).5.5.6 The measurements obtained have also proven sensitive to differences in conditioning (see Section 10). Many materials, products, or assemblies, such as some carpeting, wood, plastics, or textiles, require long periods to attain equilibrium (constant weight) even in a forced-draft conditioning chamber. This sensitivity reflects the inherent natural variability of the sample and is not specific to the test method.5.5.7 In this procedure, the specimens are subjected to one or more specific sets of laboratory test conditions. If different test conditions are substituted or the end-use conditions are changed, it is not necessarily possible by or from this test method to predict changes in the fire-test-response characteristics measured; therefore, the results are valid only for the fire test exposure conditions described in this procedure.5.5.8 This test method solves some limitations associated with other closed chamber test methods, such as Test Method E662 (2-6) (see 5.4.1). The test method retains some limitations related to closed chamber tests, as detailed in 5.5.8.1 – 5.5.8.5.5.5.8.1 Information relating the specific optical density obtained by this test method to the mass lost by the specimen during the test is possible only by using the (optional) load cell, to determine the mass optical density (see Annex A1).5.5.8.2 All specimens consume oxygen when combusted. The smoke generation of some specimens (especially those undergoing rapid combustion and those which are heavy and multilayered) is influenced by the oxygen concentration in the chamber. Thus, if the atmosphere inside the chamber becomes oxygen-deficient before the end of the experiment, combustion may ceases for some specimens; therefore, it is possible that those layers furthest away from the radiant source will not undergo combustion.5.5.8.3 The presence of walls causes losses through deposition of combustion particulates.5.5.8.4 Soot and other solid or liquid combustion products settle on the optical surfaces during a test, resulting in potentially higher smoke density measurements than those due to the smoke in suspension.5.5.8.5 This test method does not carry out dynamic measurements as smoke simply continues filling a closed chamber; therefore, the smoke obscuration values obtained do not represent conditions of open fires.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 conditions.1.9 Fire testing of products and materials is inherently hazardous, and adequate safeguards for personnel and property shall be employed in conducting these tests. This test method may involve hazardous materials, operations, and equipment. See also 6.2.1.2, Section 7, and 11.7.2.1.10 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.11 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1.1 This practice provides for the description of the various parameters of sources used to excite the spectra in optical emission spectrochemical analysis. Recent research on sampling and excitation of metals has shown that the critical parameter to control is the current through the specimen and circuit although the actual mechanism of sampling is unknown. A specific current can be achieved by several combinations of capacitance, voltage, resistance, and inductance, depending on the values for all four. A practice consisting of component values only is insufficient to properly describe an excitation source. 1.2 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 This method is intended for use by laboratories performing calibration of a spectroradiometer for spectral irradiance measurements using a spectral irradiance standard with known spectral irradiance values and associated uncertainties traceable to a national metrological laboratory that has participated in intercomparisons of standards of spectral irradiance, known uncertainties and known measurement geometry.4.2 This method is generalized to allow for the use of different types of input optics provided that those input optics are suitable for the wavelength range and measurement geometry of the calibration.4.3 This method is generalized to allow for the use of different types of monochromators provided that they can be configured for a bandwidth, wavelength range, and throughput levels suitable for the calibration being performed.4.4 This method is generalized to allow for the use of different types of optical radiation detectors provided that the spectral response of the detector over the wavelength range of the calibration is appropriate to the signal levels produced by the monochromator.1.1 This test method covers the calibration of spectroradiometers for the measurement of spectral irradiance using a standard of spectral irradiance that is traceable to a national metrological laboratory that has participated in intercomparisons of standards of spectral irradiance.1.2 This method is not limited by the input optics of the spectroradiometric system. However, choice of input optics affects the overall uncertainty of the calibration.1.3 This method is not limited by the type of monochromator or optical detector used in the spectroradiometer system. Parts of the method may not apply to determine which parts apply to the specific spectroradiometer being used. It is important that the choice of monochromator and detector be appropriate for the wavelength range of interest for the calibration. Though the method generally applies to photodiode array detector based systems, the user should note that these types of spectroradiometers often suffer from stray light problems and have limited dynamic range. Diode array spectroradiometers are not recommended for use in the ultraviolet range unless these specific problems are addressed.1.4 The calibration described in this method employs the use of a standard of spectral irradiance. The standard of spectral irradiance must have known spectral irradiance values at given wavelengths for a specific input current and clearly defined measurement geometry. Uncertainties must also be known for the spectral irradiance values. The values assigned to this standard must be traceable to a national metrological laboratory that has participated in intercomparisons of standards of spectral irradiance. These standards may be obtained from a number of national standards laboratories and commercial laboratories. The spectral irradiance standards consist mainly of tungsten halogen lamps with coiled filaments enclosed in a quartz envelope, though other types of lamps are used. Standards can be obtained with calibration values covering all or part of the wavelength range from 200 to 4500 nm.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.21.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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