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4.1 The major factors affecting the quality of a CT image are total image unsharpness (UTimage), contrast (Δµ), and random noise (σ). Geometrical and detector unsharpness limit the spatial resolution of a CT system, that is, its ability to image fine structural detail in an object. Random noise and contrast response limit the contrast sensitivity of a CT system, that is, its ability to detect the presence or absence of features in an object. Spatial resolution and contrast sensitivity may be measured in various ways. In this test method, spatial resolution is quantified in terms of the modulation transfer function (MTF), and contrast sensitivity is quantified in terms of the contrast discrimination function (CDF). The relationship between contrast sensitivity and spatial resolution describing the resolving and detecting capabilities is given by the contrast-detail-diagram (CDD metric, see also Guide E1441 and Practice E1570). This test method allows the purchaser or the provider of CT systems or services, or both, to measure and specify spatial resolution and contrast sensitivity and is a measure for system stability over time and performance acceptability.1.1 This test method provides instruction for determining the spatial resolution and contrast sensitivity in X-ray and γ-ray computed tomography (CT) volumes. The determination is based on examination of the CT volume of a uniform cylinder of material. The spatial resolution measurement (Modulation Transfer Function) is derived from an image analysis of the sharpness at the edges of the reconstructed cylinder slices. The contrast sensitivity measurement (Contrast Discrimination Function) is derived from an image analysis of the contrast and the statistical noise at the center of the cylinder slices.1.2 This test method is more quantitative and less susceptible to interpretation than alternative approaches because the required cylinder is easy to fabricate and the analysis easy to perform.1.3 This test method is not to predict the detectability of specific object features or flaws in a specific application. This is subject of IQI and RQI standards and standard practices.1.4 This method tests and describes overall CT system performance. Performance tests of systems components such as X-ray tubes, gamma sources, and detectors are covered by separate documents, namely Guide E1000, Practice E2737, and Practice E2002; c.f. 2.1, which should be consulted for further system analysis.1.5 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.6 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.1.7 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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4.1 This test method is well suited for measuring the viscosity of glasses in ranges higher than those covered by parallel plate (see Test Method C1351M) and rotational viscometry (see Practice C965) methods. This test method is useful for providing information related to the behavior of glass after it has been formed into an object of commerce and in research and development.1.1 This test method covers the determination of glass viscosity from approximately 108 Pa·s to approximately 1013 Pa·s by measuring the rate of viscous bending of a simply loaded glass beam.2 Due to the thermal history of the glass, the viscosity may not represent conditions of thermal equilibrium at the high end of the measured viscosity range. Measurements carried out over extended periods of time at any temperature or thermal preconditioning will minimize these effects by allowing the glass to approach equilibrium structural conditions. Conversely, the method also may be used in experimental programs that focus on nonequilibrium conditions.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 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.1.4 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 Measurements of RI made by this test method, with the 0.2° observation angle, are related to visual observation of raised retroreflective pavement markers at distances of approximately 220 m (720 ft) for cars or approximately 440 m (1440 ft) for trucks when illuminated by tungsten filament light sources such as car headlights.5.2 There are some castings that block vehicle illumination of a portion of the marker mounted within it. In this case, measured RI can be significantly lower than when the marker is photometered outside the casting, but will correspond to the visual observation.5.3 The test method is not applicable to raised pavement markers mounted in depressions cut into the pavement.5.4 The coefficient of luminous intensity of raised retroreflective pavement markers degrades with traffic wear and requires periodic measurement to ensure that sufficient visibility is provided to the driver.5.5 The quality of the pavement markers as to materials used, age and wear pattern, will have an effect on the coefficient of (retroreflected) luminous intensity. These conditions need to be observed and noted by the user.1.1 This test method covers the measurement of the retroreflective properties of raised retroreflective pavement markers at a prescribed geometry, by means of a portable retroreflectometer that can be used in the field. The measurements can be compared to minimum requirements to determine the need for replacement.1.2 The observation angle specified for retroreflectometers in this test method is that currently specified for raised pavement markers in the United States and may differ from the angles used elsewhere. For other jurisdictions, replace the observations angle specified herein with the observation angle specified by the pertinent agency.1.3 This test method is intended to be used for field measurement of raised retroreflective pavement markers but may also be used to measure the performance of new markers before they are placed in the field.1.4 This test method covers measurements of raised pavement markers mounted on a road surface or mounted in snow-plowable metal castings.1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.6 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.1.7 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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4.1 This test method is well suited for measuring the viscosity of glasses between the range within which rotational viscometry (see Practice C965) is useful and the range within which beam bending viscometry is useful (see Test Method C1350M). It can be used to determine the viscosity/temperature curve in the region near the softening point (see Test Method C338). This test method is useful for providing information related to the behavior of glass as it is formed into an object of commerce, and in research and development.1.1 This test method covers the determination of the viscosity of glass from 104 Pa·s to 108 Pa·s by measuring the rate of viscous compression of a small, solid cylinder.21.2 The values stated in SI units are to be regarded as the standard.1.3 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.1.4 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 Users of fire test data often need a quantitative indication of the quality of the data presented in a test report. This quantitative indication is referred to as the “measurement uncertainty”. There are two primary reasons for estimating the uncertainty of fire test results.5.1.1 ISO/IEC 17025 requires that competent testing and calibration laboratories include uncertainty estimates for the results that are presented in a report.5.1.2 Fire safety engineers need to know the quality of the input data used in an analysis to determine the uncertainty of the outcome of the analysis.1.1 This guide covers the evaluation and expression of uncertainty of measurements of fire test methods developed and maintained by ASTM International, based on the approach presented in the GUM. The use in this process of precision data obtained from a round robin is also discussed.1.2 The guidelines presented in this standard can also be applied to evaluate and express the uncertainty associated with fire test results. However, it may not be possible to quantify the uncertainty of fire test results if some sources of uncertainty cannot be accounted for. This problem is discussed in more detail in Appendix X2.1.3 Application of this guide is limited to tests that provide quantitative results in engineering units. This includes, for example, methods for measuring the heat release rate of burning specimens based on oxygen consumption calorimetry, such as Test Method E1354.1.4 This guide does not apply to tests that provide results in the form of indices or binary results (for example, pass/fail). For example, the uncertainty of the Flame Spread Index obtained according to Test Method E84 cannot be determined.1.5 In some cases additional guidance is required to supplement this standard. For example, the expression of uncertainty of heat release rate measurements at low levels requires additional guidance and uncertainties associated with sampling are not explicitly addressed.1.6 This fire standard cannot be used to provide quantitative measures.1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 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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This field-test method provides chloride and fluoride concentration results on a dry basis. Concentration data for gaseous chlorides and fluorides are assumed to be hydrochloric acid gas, and hydrofluoric acid gas when calculating mass emission rates.Mass emission rates of HCl and HF can be calculated if the effluent volumetric flow rate is known. Volumetric flow rates can be calculated by conducting EPA Methods 1–4 or their equivalents.This field test method provides data having bias and precision for HCl consistent with the values in Section 14. In addition, the test-specific bias can be assessed for each test by conducting the post-test quality assurance check. The procedure is identified as optional, and the performance of this procedure depends on the test specific data quality objectives, and end use of the data.The test-specific precision may be determined by conducting paired-runs. Paired runs aid in identifying possible suspect data and provide backup in the event one train is invalidated. Performing paired runs depends on the test-specific data quality objectives.The reaction of gaseous HCl with ammonia (NH3) to form solid ammonium chloride (NH4Cl) is well known. At stack temperatures common to the exits of baghouses and ESPs at mineral calcining facilities (that is, 250 to 450°F or 121 to 232°C), an equilibration between the gaseous HCl/NH3, the condensed NH4Cl(s), and the effluent particulate matter can exist. It is impossible to know the exact partition ratio between the gas and particulate phases of these compounds in the sampling system. Furthermore, it is very difficult to control the effects of these partitioning reactions within the various sampling system components.Note 4—Use of this method is cautioned when trying to quantify HCl (g) in the presence of ammonium chloride and ammonia.1.1 This method will measure the concentration of gaseous hydrochloric and hydrofluoric acids, and other gaseous chlorides and fluorides that pass through a particulate matter filter maintained at 177°C (350°F). This method is specific for sampling combustion effluent from mineral calcining industries and other stationary sources where the reactive/adsorptive nature of the particulate matter may affect measurements.1.2 This method utilizes ion chromatography to quantify the aqueous samples, and thus measures only the C1- and F- ions.1.3 Based on a one-hour sampling run, the method will provide results of known accuracy and precision for chloride and fluoride in-stack concentrations of 0.5 ppm (v) dry or greater. Extending the run duration and sampling a greater volume of effluent will extend the range to lower concentrations.1.4 This method includes optional post-test quality assurance procedures to assess the bias of the test results, and optional paired sample train runs to assess the precision of test results.

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5.1 This test method allows for the measurement of the torque retention properties of container/continuous thread closure systems of various designs, materials, and manufacture, and is suitable for packaging development and engineering evaluation.5.2 This test method can be used for the evaluation of container/continuous thread closure systems under controlled conditions (where the application torque is known and the applied downward force to the closure is zero).5.3 This test method measures torque retention properties of container/continuous thread closure systems with the use of a non-automated, spring torque-meter (with either a dial indicator or a digital readout) or a torque wrench.1.1 These test methods evaluate the torque retention of continuous thread closures on containers, with matching finishes, for predetermined environmental conditions over time.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.NOTE 1: The SI unit system is the recommended system.1.3 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.1.4 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 is meant to allow for a rapid (24 h) index of a geomedia's sorption affinity for given solutes in environmental waters or leachates. A large number of samples may be run in parallel using this test method to determine a comparative ranking of those samples, based upon the amount of solute sorbed by the geomedia, or by various geomedia or leachate constituents. The 24 h time is used to make the test convenient and also to minimize microbial, light, or hydrolytic degradation which may be a problem in longer timed procedures. While Kd values are directly applicable for screening and comparative ranking purposes, their use in predictive field applications generally requires the assumption that Kd be a fixed value.5.2 While this test method may be useful in determining 24 h Kd values for nonvolatile organic constituents, interlaboratory testing has been carried out only for the nonvolatile inorganic species arsenic and cadmium (see Section 12). However, the procedure has been tested for single-laboratory precision with polychlorinated biphenyls (PCBs) and is believed to be useful for all stable and nonvolatile inorganic and organic constituents. This test method is not considered appropriate for volatile constituents.5.3 The 24 h time limit may be sufficient to reach a steady-state Kd; however, the calculated Kd value should be considered a non-equilibrium measurement unless steady-state has been determined. To report this determination as a steady-state Kd, this test method should be conducted for intermediate times (for example, 12, 18, and 22 h) to ensure that the soluble concentrations in the solution have reached a steady state by 24 h. If a test duration of greater than 24 h is required, refer to Test Method D4319 for an alternate procedure of longer duration.1.1 This test method describes a procedure for determining the sorption affinity of waste solutes by unconsolidated geologic material in aqueous suspension. The waste solute may be derived from a variety of sources such as wells, underdrain systems, or laboratory solutions such as those produced by waste extraction tests like the Practice D3987 shake extraction method.1.2 This test method is applicable in screening and providing relative rankings of a large number of geomedia samples for their sorption affinity in aqueous leachate/geomedia suspensions. This test method may not simulate sorption characteristics that would occur in unperturbed geologic settings.1.3 While this procedure may be applicable to both organic and inorganic constituents, care must be taken with respect to the stability of the particular constituents and their possible losses from solution by such processes as degradation by microbes, light, hydrolysis, or sorption to material surfaces. This test method should not be used for volatile chemical constituents (see 6.1).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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4.1 In a series-connected multijunction PV device, the incident total and spectral irradiance determines which component cell will generate the smallest photocurrent and thus limit the current through the entire series-connected device. This current-limiting behavior also affects the fill factor of the device. Because of this, special techniques are needed to measure the correct I-V characteristics of multijunction devices under the desired reporting conditions (see Test Methods E1036).4.2 These test methods use a numerical parameter called the current balance which is a measure of how well the test conditions replicate the desired reporting conditions. When the current balance deviates from unity by more than 0.03, the uncertainty of the measurement may be increased.4.3 The effects of current limiting in individual component cells can cause problems for I-V curve translations to different temperature and irradiance conditions, such as the translations recommended in Test Methods E1036. For example, if a different component cell becomes the limiting cell as the irradiance is varied, a discontinuity in the current versus irradiance characteristic may be observed. For this reason, it is recommended that I-V characteristics of multijunction devices be measured at temperature and irradiance conditions close to the desired reporting conditions.4.4 Some multijunction devices have more than two terminals which allow electrical connections to each component cell. In these cases, the special techniques for spectral response measurements are not needed because the component cells can be measured individually. However, these I-V techniques are still needed if the device is intended to be operated as a two-terminal device.4.5 Using these test methods, the spectral response is typically measured while the individual component cell under test is illuminated at levels that are less than Eo. Nonlinearity of the spectral response may cause the measured results to differ from the spectral response at the illumination levels of actual use conditions.1.1 These test methods provide special techniques needed to determine the electrical performance and spectral response of two-terminal, multijunction photovoltaic (PV) devices, both cell and modules.1.2 These test methods are modifications and extensions of the procedures for single-junction devices defined by Test Methods E948, E1021, and E1036.1.3 These test methods do not include temperature and irradiance corrections for spectral response and current-voltage (I-V) measurements. Procedures for such corrections are available in Test Methods E948, E1021, and E1036.1.4 These test methods may be applied to cells and modules intended for concentrator applications.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 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.1.7 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 is designed to provide color data obtained from spectral reflectance factors at specific illumination and detection angles for interference pigments. Information presented in this test method is based upon data taken on materials exclusively pigmented with interference pigments.5.2 These data can be used for acceptance testing, design purposes, research, manufacturing control, and quality control.5.3 Specimens must be statistically representative of the end use.5.4 Applicability of this test method for other materials, including combining interference pigments with absorbing and scattering pigments should be confirmed by the user.1.1 This test method covers the instrumental requirements and required parameters needed to make instrumental color measurements of thin film interference pigments. This test method is designed to encompass interference pigments used in architectural applications, automobiles, coatings, cosmetics, inks, packaging, paints, plastics, printing, security, and other applications.1.2 Characterization of the optical behavior of materials colored with interference pigments requires measurement at multiple angles of illumination and detection.1.3 Data taken utilizing this test method are quantitative and are appropriate for quality control of interference pigment color.1.4 The measurement results are usually expressed as reflectance factors, tristimulus color values, or as CIE L*a*b* color coordinates and color difference.1.5 The totality of data taken may not be necessary for evaluating mixtures also containing non-interference pigments. The committee is investigating and evaluating the appropriateness of this test method for those materials. It is the responsibility of the users to determine the applicability of this test method for their specific applications.1.6 Interference pigments are typically evaluated for color and color appearance in a medium, such as paint or ink. The gonioapparent effect depends strongly on the physical and chemical properties of the medium. Some of the properties affecting color and color appearance include vehicle viscosity, thickness, transparency, and volume solids. As a general rule, for quality control purposes, interference pigments are best evaluated in a masstone product form. In some cases this product form may be the final product form, or more typically a qualified simulation of the intended product form (such as a paint drawdown) that in terms of color and appearance correlates to final product application.1.7 This standard does not address the requirements for characterizing materials containing metal flake pigments. Measurements of the optical characteristics of materials containing metal flake pigments are described in Test Method E2194.1.8 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.9 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.1.10 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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