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4.1 This practice permits an analyst to compare the general performance of an instrument on any given day with the prior performance of an instrument. This practice is not necessarily meant for comparison of different instruments with each other even if the instruments are of the same type and model. This practice is not meant for comparison of the performance of one instrument operated under differing conditions.1.1 This practice describes two levels of tests to measure the performance of laboratory Fourier transform mid-infrared (FT-MIR) spectrometers equipped with a standard sample holder used for transmission measurements.1.2 This practice is not directly applicable to Fourier transform infrared (FT-IR) spectrometers equipped with various specialized sampling accessories such as flow cells or reflectance optics, nor to Fourier transform near-infrared (FT-NIR) spectrometers, nor to FT-IR spectrometers run in step scan mode.1.2.1 If the specialized sampling accessory can be removed and replaced with a standard transmission sample holder, then this practice can be used. However, the user should recognize that the performance measured may not reflect that which is achieved when the specialized accessory is in use.1.2.2 If the specialized sampling accessory cannot be removed, then it may be possible to employ a modified version of this practice to measure spectrometer performance. The user is referred to Guide E1866 for a discussion of how these tests may be modified.1.2.3 Spectrometer performance tests for FT-NIR spectrometers are described in Practice E1944.1.2.4 Performance tests for dispersive MIR instruments are described in Practice E932.1.2.5 For FT-IR spectrometers run in a step scan mode, variations on this practice and information provided by the instrument vendor should be used.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3.1 Exception—Informational inch-pound units are provided in 5.4.1.4 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.1.5 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 test method covers the testing of the spectral bandwidth and wavelength accuracy of fluorescence spectrometers that use a monochromator for emission wavelength selection and photomultiplier tube detection. The method can be applied to instruments that use multi-element detectors, such as diode arrays, but results must be interpreted carefully. Atomic lines between 250 nm and 1000 nm are used in the method. The difference between the apparent wavelength and the known wavelength for a series of atomic emission lines is used as a test for wavelength accuracy. The apparent width of some of these lines is used as a test for spectral bandwidth.1.1 This test method covers the testing of the spectral bandwidth and wavelength accuracy of fluorescence spectrometers that use a monochromator for emission wavelength selection and photomultiplier tube detection. This test method can be applied to instruments that use multi-element detectors, such as diode arrays, but results must be interpreted carefully. This test method uses atomic lines between 250 nm and 1000 nm.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 This practice describes the essential components of an ICP-AES. The components include excitation/radio-frequency generators, sample introduction systems, spectrometers, detectors, and signal processing and displays. This description allows the user or potential user to gain a cursory understanding of an ICP-AES system. This practice also provides a means for comparing and evaluating various systems, as well as understanding the capabilities and limitations of each instrument.5.2 Training—The manufacturer should provide training in safety, basic theory of ICP-AES analysis, operations of hardware and software, and routine maintenance for at least one operator. Training ideally should consist of the basic operation of the instrument at the time of installation, followed by an in-depth course one or two months later. Advanced courses are also offered at several of the important spectroscopy meetings that occur throughout the year as well as by independent training institutes. Several independent consultants are available who can provide training, sometimes at the user's site.1.1 This practice describes the components of an inductively coupled plasma atomic emission spectrometer (ICP-AES) that are basic to its operation and to the quality of its performance. This practice identifies critical factors affecting accuracy, precision, and sensitivity. It is not the intent of this practice to specify component tolerances or performance criteria, since these are unique for each instrument. A prospective user should consult with the manufacturer before placing an order, to design a testing protocol that demonstrates the instrument meets all anticipated needs.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.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 and health practices and determine the applicability of regulatory limitations prior to use. Specific safety hazard statements are given in Section 13.

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4.1 Generally, Raman spectra measured using grating-based dispersive or Fourier transform Raman spectrometers have not been corrected for the instrumental response (spectral responsivity of the detection system). Raman spectra obtained with different instruments may show significant variations in the measured relative peak intensities of a sample compound. This is mainly as a result of differences in their wavelength-dependent optical transmission and detector efficiencies. These variations can be particularly large when widely different laser excitation wavelengths are used, but can occur when the same laser excitation is used and spectra of the same compound are compared between instruments. This is illustrated in Fig. 1, which shows the uncorrected luminescence spectrum of SRM 2241, acquired upon four different commercially available Raman spectrometers operating with 785 nm laser excitation. Instrumental response variations can also occur on the same instrument after a component change or service work has been performed. Each spectrometer, due to its unique combination of filters, grating, collection optics and detector response, has a very unique spectral response. The spectrometer dependent spectral response will of course also affect the shape of Raman spectra acquired upon these systems. The shape of this response is not to be construed as either “good or bad” but is the result of design considerations by the spectrometer manufacturer. For instance, as shown in Fig. 1, spectral coverage can vary considerably between spectrometer systems. This is typically a deliberate tradeoff in spectrometer design, where spectral coverage is sacrificed for enhanced spectral resolution.FIG. 1 SRM 2241 Measured on Four Commercial Raman Spectrometers Utilizing 785 nm Excitation4.2 Variations in spectral peak intensities can be mostly corrected through calibration of the Raman intensity (y) axis. The conventional method of calibration of the spectral response of a Raman spectrometer is through the use of a National Metrology Institute (NMI), for example, NIST, traceable calibrated irradiance source. Such lamps have a defined spectral output of intensity versus wavelength and procedures for their use have been published (1)5. However, intensity calibration using a white-light source can present experimental difficulties, especially for routine analytical work. Calibrated tungsten halogen lamps have a limited lifetime and require periodic recalibration. These lamps are often mounted in an integrating sphere to eliminate polarization effects and provide uniform source irradiance. In practice, these sources can be difficult to align with the variety of sampling arrangements that are now typical with Raman spectrometers, especially microscope based systems and process Raman analyzers where electrical safety concerns persist in hazardous areas. The advantage of a standard lamp is that it can be used for multiple excitation wavelengths.4.3 The spectra of materials that luminesce with irradiation can be corrected for relative luminescence intensity as a function of emission wavelength using a calibrated Raman spectrometer. An irradiance source, traceable to the SI, can be used to calibrate the spectrometer. Several groups have proposed these transfer standards to calibrate both Raman and fluorescence spectrometers (1-6). The use of a luminescent glass material has the advantage that the Raman excitation laser is used to excite the luminescence emission and this emission is measured in the same position as the sample. These glasses can be used in a variety of sampling configurations and they require no additional instrumentation. The glasses are photostable and unlike primary calibration sources, may not require periodic recalibration. NIST provides a series of fluorescent glasses that may be used to calibrate the intensity axis of Raman spectrometers. A mathematical equation, which is a description of the corrected emission, is provided with each glass. The operator uses this mathematical relation with a measurement of the glass on their spectrometer to produce a system correction curve.4.4 This guide describes the steps required to produce a relative intensity correction curve for a Raman spectrometer using a calibrated standard source or a NIST SRM and a means to validate the correction.1.1 This guide is designed to enable the user to correct a Raman spectrometer for its relative spectral-intensity response function using NIST Standard Reference Materials2 in the 224X series (currently SRMs 2241, 2242, 2243, 2244, 2245, 2246), or a calibrated irradiance source. This relative intensity correction procedure will enable the intercomparison of Raman spectra acquired from differing instruments, excitation wavelengths, and laboratories.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 Because of the significant dangers associated with the use of lasers, ANSI Z136.1 or suitable regional standards should be followed in conjunction with this practice.1.4 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.1.5 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 practice should be used by the developer of standard test methods that employ surrogate calibrations.5.1.1 This practice assists the test method developer in setting and documenting requirements for the spectrometer/spectrophotometers that can perform the test method.5.1.2 This practice assists the test method developer in setting and documenting spectral data collection and computation parameters for the test method.5.1.3 This practice assists the test method developer in selecting among possible multivariate analysis procedures that could be used to establish the surrogate calibration. The practice describes statistical tests that should be performed to ensure that all multivariate analysis procedures that are allowed within the scope of the test method produce statistically indistinguishable results.5.1.4 This practice describes statistical calculations that the test method developer should perform on the calibration and qualification data that should be collected as part of the ILS that establishes the test method precision. These calculations establish the level of performance that spectrometers/spectrophotometers must meet in order to perform the test method.5.2 This practice describes how the person who calibrates a spectrometer/spectrophotometer can test the performance of said spectrometer/spectrophotometer to determine if the performance is adequate to conduct the test method.5.3 This practice describes how the user of a spectrometer/spectrophotometer can qualify the spectrometer/spectrophotometer to conduct the test method.1.1 This practice relates to the multivariate calibration of spectrometers and spectrophotometers used in determining the physical and chemical characteristics of materials. A detailed description of general multivariate analysis is given in Practices E1655. This standard refers only to those instances where surrogate mixtures can be used to establish a suitable calibration matrix. This practice specifies calibration and qualification data set requirements for interlaboratory studies (ILSs), that is, round robins, of standard test methods employing surrogate calibration techniques that do not conform exactly to Practices E1655.NOTE 1: For some multivariate spectroscopic analyses, interferences and matrix effects are sufficiently small that it is possible to calibrate using mixtures that contain substantially fewer chemical components than the samples that will ultimately be analyzed. While these surrogate methods generally make use of the multivariate mathematics described in Practices E1655, they do not conform to procedures described therein, specifically with respect to the handling of outliers.1.2 This practice specifies how the ILS data is treated to establish spectrometer/spectrophotometer performance qualification requirements to be incorporated into standard test methods.NOTE 2: Spectrometer/spectrophotometer qualification procedures are intended to allow the user to determine if the performance of a specific spectrometer/spectrophotometer is adequate to conduct the analysis so as to obtain results consistent with the published test method precision.1.2.1 The spectroscopies used in the surrogate test methods would include but not be limited to mid- and near-infrared, ultraviolet/visible, fluorescence and Raman spectroscopies.1.2.2 The surrogate calibrations covered in this practice are: multilinear regression (MLR), principal components regression (PCR) or partial least squares (PLS) mathematics. These calibration procedures are described in detail in Practices E1655.1.3 For surrogate test methods, this practice recommends limitations that should be placed on calibration options that are allowed in the test method. Specifically, this practice recommends that the test method developer demonstrate that all calibrations that are allowed in the test method produce statistically indistinguishable results.1.4 For surrogate test methods that reference spectrometer/spectrophotometer performance practices, such as Practices E275, E925, E932, E958, E1421, E1683, or E1944; Test Methods E387, E388, or E579; or Guide E1866, this practice recommends that instrument performance data be collected as part of the ILS to establish the relationship between spectrometer/spectrophotometer performance and test method precision.

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5.1 Auger electron spectroscopy and X-ray photoelectron spectroscopy are used extensively for the surface analysis of materials. This practice summarizes methods for determining the specimen area contributing to the detected signal (a) for instruments in which a focused electron beam can be scanned over a region with dimensions greater than the dimensions of the specimen area viewed by the analyzer, and (b) by employing a sample with a sharp edge.5.2 This practice is intended as a means for determining the observed specimen area for selected conditions of operation of the electron energy analyzer. The observed specimen area depends on whether or not the electrons are retarded before energy analysis, the analyzer pass energy or retarding ratio if the electrons are retarded before energy analysis, the size of selected slits or apertures, and the value of the electron energy to be measured. The observed specimen area depends on these selected conditions of operation and also can depend on the adequacy of alignment of the specimen with respect to the electron energy analyzer.5.3 Any changes in the observed specimen area as a function of measurement conditions, for example, electron energy or analyzer pass energy, may need to be known if the specimen materials in regular use have lateral inhomogeneities with dimensions comparable to the dimensions of the specimen area viewed by the analyzer.5.4 This practice can give useful information on the imaging properties of the electron energy analyzer for particular conditions of operation. This information can be helpful in comparing analyzer performance with manufacturer's specifications.5.5 Information about the shape and size of the area viewed by the analyzer can also be employed to predict the signal intensity in XPS experiments when the sample is rotated and to assess the axis of rotation of the sample manipulator.5.6 Examples of the application of the methods described in this practice have been published (1-7).55.7 There are different ways to define the spectrometer analysis area. An ISO Technical Report provides guidance on determinations of lateral resolution, analysis area, and sample area viewed by the analyzer in AES and XPS(8), and ISO 18516:2006 describes three methods for determination of lateral resolution in AES and XPS. Baer and Engelhard have used well-defined ‘dots’ of a material on a substrate to determine the area of a specimen contributing to the measured signal of a ‘small-area’ XPS measurement (9). This area could be as much as ten times the area estimated simply from the lateral resolution of the instrument. The amount of intensity in ‘fringe’ or ‘tail’ regions could also be highly dependent on lens operation and the adequacy of specimen alignment. Scheithauer described an alternative technique in which Pt apertures of varying diameters were utilized to determine the fraction of ‘long-tail’ X-ray contributions outside each aperture on the measured Pt photoelectron signal compared to that on a Pt foil (10). In test measurements on a commercial XPS instrument with a focused X-ray beam and a nominal lateral resolution of 10 μm (as determined from the distance between the positions for 20 %  and 80 % of maximum signal when scans were made across an edge), it was found that aperture diameters of about 100 μm and 450 μm were required to reduce the photoelectron signals to 10 % and 1 %, respectively, of the maximum value (10). Knowledge of the effective analysis area is important when making tradeoffs between lateral resolution and detectability. In scanning Auger microscopy, the area of analysis is determined more by the radial extent of backscattered electrons than by the radius of the primary beam (11, 12, 13).1.1 This practice describes methods for determining the specimen area contributing to the detected signal in Auger electron spectrometers and some types of X-ray photoelectron spectrometers (spectrometer analysis area) when this area is defined by the electron collection lens and aperture system of the electron energy analyzer. The practice is applicable only to those X-ray photoelectron spectrometers in which the specimen area excited by the incident X-ray beam is larger than the specimen area viewed by the analyzer, in which the photoelectrons travel in a field-free region from the specimen to the analyzer entrance. Some of the methods described here require an auxiliary electron gun mounted to produce an electron beam of variable energy on the specimen (“electron-gun method”). Other experiments require a sample with a sharp edge, such as a wafer covered with a uniform clean layer (for example, gold (Au) or silver (Ag)) and cleaved to obtain a long side (“sharp-edge method”).1.2 This practice is recommended as a useful means for determining the specimen area viewed by the analyzer for different conditions of spectrometer operation, for verifying adequate specimen and beam alignment, and for characterizing the imaging properties of the electron energy analyzer.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 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.1.5 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 practice permits an analyst to compare the performance of an NMR spectrometer for a particular test on any given day with the instrument's prior performance for that test. The practice can also provide sufficient quantitative performance information for problem diagnosis and solving. If complete information about how a test is carried out is supplied and sufficient replicates are collected to substantiate statistical relevance, the tests in this practice can be used to establish the setting and meeting of relevant performance specifications. This practice is not necessarily meant for the comparison of different instruments with each other, even if the instruments are of the same type and model. This practice is not meant for the comparison of the performance of different instruments operated under conditions differing from those specified for a particular test.1.1 This practice covers procedures for measuring and reporting the performance of Fourier-transform nuclear magnetic resonance spectrometers (FT-NMRs) using liquid samples.1.2 This practice is not directly applicable to FT-NMR spectrometers outfitted to measure gaseous, anisotropically structured liquid, semi-solid, or solid samples; those set up to work with flowing sample streams; or those used to make hyperpolarization measurements.1.3 This practice was expressly developed for FT-NMR spectrometers operating with proton resonance frequencies between 200 MHz and 1200 MHz.1.4 This practice is not directly applicable to continuous wave (scanning) NMR spectrometers.1.5 This practice is not directly applicable to instruments using single-sideband detection.1.6 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.7 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.1.8 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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4.1 This practice describes to the end user how to collect the FT-IR spectra of in-service oil samples for in-service oil condition monitoring. Various in-service oil condition monitoring parameters, such as oxidation, nitration, soot, water, ethylene glycol, fuel dilution, gasoline dilution, sulfate by-products and phosphate antiwear additives, can be measured by FT-IR spectroscopy (4-7). Changes in the values of these parameters over operating time can then be used to help diagnose the operational condition of various machinery and equipment and to indicate when an oil change should take place. This practice is intended to give a standardized configuration for FT-IR instrumentation and operating parameters employed in in-service oil condition monitoring in order to obtain comparable between-instrument and between-laboratory data.1.1 This practice covers the instrument set-up and operation parameters for using FT-IR spectrometers for in-service oil condition monitoring for both direct trend analysis and differential trend analysis approaches.1.2 This practice describes how to acquire the FT-IR spectrum of an in-service oil sample using a standard transmission cell and establishes maximum allowable spectral noise levels.1.3 Measurement and integrated parameters for individual in-service oil condition monitoring components and parameters are not described in this practice and are described in their respective test methods.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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This practice should first be used to establish the operating characteristics of a particular X-ray photoelectron spectrometer at a time when the spectrometer performance is known to be optimum. Hence, the spectrometer settings in Section 5 and the expected performance figures given in Section 7 are to be taken only as guides, to be supplanted by the behavior of the user’actual spectrometer. Subsequently, this practice should be used as a routine check, performed at frequent intervals with the same instrument settings, and the results compared with those obtained in 4.1. Significant deviation from optimum performance may indicate that the spectrometer requires recalibration or other maintenance. Typical analysis settings should be used with this practice. The use of settings not specified by this practice is left to the discretion of the user, however, the settings should be recorded in accordance with Practice E 996 and the same settings should be used consistently whenever this practice is repeated, so that the results obtained will be directly comparable to previous results.1.1 This practice covers a procedure for checking some of the operating characteristics of an X-ray photoelectron spectrometer. Tests herein provide checks of the repeatability of intensity measurements and the drift of the intensities with time. This practice may be conducted at the same time as the spectrometer energy calibration using Practice E 2108.1.2 LimitationsThis practice is meant to augment, and not to replace, the calibration procedures recommended by the manufacturer of the spectrometer. This practice is also not meant to be used as a means of comparison between X-ray photoelectron spectrometers, but only as a self-consistent check of the operating characteristics of an individual spectrometer.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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 The analyst may use this document to obtain information on the properties of electron spectrometers and instrumental aspects associated with quantitative surface analysis.1.1 The purpose of this guide is to familiarize the analyst with some of the relevant literature describing the physical properties of modern electrostatic electron spectrometers.1.2 This guide is intended to apply to electron spectrometers generally used in Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS).1.3 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.1.4 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.1.5 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 practice is intended for all infrared spectroscopists who are using dispersive instruments for qualitative or quantitative areas of analysis.4.2 The purpose of this practice is to set forth performance guidelines for testing instruments used in developing an analytical method. These guidelines can be used to compare an instrument in a specific application with the instrument(s) used in developing the method.4.3 An infrared procedure must include a description of the instrumentation and of the performance needed to duplicate the precision and accuracy of the method.1.1 This practice covers the necessary information to qualify dispersive infrared instruments for specific analytical applications, and especially for methods developed by ASTM International.1.2 This practice is not to be used as a rigorous test of performance of instrumentation.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 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.1.5 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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3.1 Calibration of the responsivity of the detection system for emission (EM) as a function of EM wavelength (λEM), also referred to as spectral correction of emission, is necessary for successful quantification when intensity ratios at different EM wavelengths are being compared or when the true shape or peak maximum position of an EM spectrum needs to be known. Such calibration methods are given here and summarized in Table 1. This type of calibration is necessary because the spectral responsivity of a detection system can change significantly over its useful wavelength range (see Fig. 1). It is highly recommended that the wavelength accuracy (see Test Method E388) and the linear range of the detection system (see Guide E2719 and Test Method E578) be determined before spectral calibration is performed and that appropriate steps are taken to insure that all measured intensities during this calibration are within the linear range. For example, when using wide slit widths in the monochromators, attenuators may be needed to attenuate the excitation beam or emission, thereby, decreasing the fluorescence intensity at the detector. Also note that when using an EM polarizer, the spectral correction for emission is dependent on the polarizer setting. (2) It is important to use the same instrument settings for all of the calibration procedures mentioned here, as well as for subsequent sample measurements.FIG. 1 Example of Relative Spectral Responsivity of Emission Detection System (Grating Monochromator-PMT Based), (see Test Method E578) for which a Correction Needs to be Applied to a Measured Instrument-Specific Emission Spectrum to Obtain its True Spectral Shape (Relative Intensities).3.2 When using CCD or diode array detectors with a spectrometer for λEM selection, the spectral correction factors are dependent on the grating position of the spectrometer. Therefore, the spectral correction profile versus λEM must be determined separately for each grating position used. (3)3.3 Instrument manufacturers often provide an automated procedure and calculation for a spectral correction function for emission, or they may supply a correction that was determined at the factory. This correction can often be applied during spectral collection or as a post-collection correction. The user should be advised to verify that the automated vendor procedure and calculation or supplied correction are performed and determined according to the guidelines given within this standard.1.1 This practice (1)2 describes three methods for determining the relative spectral correction factors for grating-based fluorescence spectrometers in the ultraviolet-visible spectral range. These methods are intended for instruments with a 0°/90° transmitting sample geometry. Each method uses different types of transfer standards, including 1) a calibrated light source (CS), 2) a calibrated detector (CD) and a calibrated diffuse reflector (CR), and 3) certified reference materials (CRMs). The wavelength region covered by the different methods ranges from 250 nm to 830 nm with some methods having a broader range than others. Extending these methods to the near infrared (NIR) beyond 830 nm will be discussed briefly, where appropriate. These methods were designed for scanning fluorescence spectrometers with a single channel detector, but can also be used with a multichannel detector, such as a diode array or a CCD.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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4.1 This practice permits an analyst to compare the general performance of a laboratory instrument on any given day with the prior performance of that instrument. This practice is not intended for comparison of different instruments with each other, nor is it directly applicable to dedicated process FT-NIR analyzers. This practice requires the use of a check sample compatible with the instrument under test as described in 5.3.1.1 This practice covers two levels of tests to measure the performance of laboratory Fourier transform near infrared (FT-NIR) spectrometers. This practice applies to the short-wave near infrared region, approximately 800 nm (12 500 cm–1) to 1100 nm (9090.91 cm–1); and the long-wavelength near infrared region, approximately 1100 nm (9090.91 cm–1) to 2500 nm (4000 cm–1). This practice is intended mainly for transmittance measurements of gases and liquids, although it is broadly applicable for reflectance measurements.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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4.1 A scanning Raman spectrometer should be checked regularly to determine if its condition is adequate for routine measurements or if it has changed. This practice is designed to facilitate that determination and, if performance is unsatisfactory, to identify the part of the system that needs attention. These tests apply for single-, double-, or triple-monochromator scanning Raman instruments commercially available. They do not apply for multichannel or Fourier transform instruments, or for gated integrator systems requiring a pulsed laser source. Use of this practice is intended only for trained optical spectroscopists and should be used in conjunction with standard texts.1.1 This practice covers routine testing of scanning Raman spectrometer performance and to assist in locating problems when performance has degraded. It is also intended as a guide for obtaining and reporting Raman spectra.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. For specific precautions, see 7.2.1.1.4 Because of the significant dangers associated with the use of lasers, ANSI Z136.1 should be followed in conjunction with this practice.1.5 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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The practice should be adopted by spectrometer manufacturers and developers of software to be used on host computers to communicate with such instruments.1.1 This practice provides a standard communications protocol for a serial communication between a host computer and a spectrometer designed for colorimetry. The adoption of the standard communication protocol on the part of instrument manufacturers will allow instrument users the option to employ third-party software, or to replace one instrument with another while retaining the same software. This standard is not intended to replace existing standards, such as SCPI-1999 written by the SCPI Consortium as a set of Standard Commands for Programmable Instruments for bench-top instruments that utilize the IEEE-488 or IEEE-488.2 interface. This standard has been adopted by many analytical instrument makers and is used by them as the interface standard for spectroscopy even when the instrument interface is RS-232c.1.2 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.

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