5.1 Reported particle size measurement is a function of both the actual particle dimension and shape factor, as well as the particular physical or chemical properties of the particle being measured. Caution is required when comparing data from instruments operating on different physical or chemical parameters or with different particle size measurement ranges. Sample acquisition, handling, and preparation can also affect the reported particle size results.1.1 These test methods cover the determination of the size distribution and quantity of particulate matter contamination from aerospace fluids isolated on a membrane filter. The microscopical techniques described may also be applied to other properly prepared samples of small particles. Two test methods are described for sizing particles as follows:1.1.1 Test Method A—Particle sizes are measured as the diameter of a circle whose area is equal to the projected area of the particle.1.1.2 Test Method B—Particle sizes are measured by their longest dimension.1.2 The test methods are intended for application to particle contamination determination of aerospace fluids, gases, surfaces, and environments.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 These test methods do not provide for sizing particles smaller than 5 μm.NOTE 1: Results of these methods are subject to variables inherent in any statistical method. The use of these methods as a standard for initially establishing limits should be avoided unless ample tolerances are permissible.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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1.1 This standard is a compilation of terminology related to the body dimensions for apparel sizing. 1.2 For definitions of other textile terms, refer to Terminology D123. 1.3 The terms are listed in alphabetical order regardless of whether they are horizontal or vertical measurements. The three dimensional Avatars were created by Alvanon Inc. See Figs. 1-19. 1.4 The term “height” has been designated for vertical measurements. 1.5 The term “length” has been designated for contour measurements.
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4.1 This test method permits a user to compare the performance of an instrument to the tolerance limit specifications stated by a manufacturer and to verify that an instrument is suitable for continued routine use. It also provides for generation of calibration data on a periodic basis, forming a database from which any changes in the performance of the instrument will be evident.4.2 This test method for the calibration verification of laser diffraction particle sizing instruments is suitable for acceptance testing of laser diffraction instruments so long as current estimates of the bias (see Section 11) and the between-laboratory precision of the test method (see Section 10) are acceptably small relative to typical laser diffraction instrument accuracy specifications; see Practice D3244.1.1 This test method describes a procedure necessary to permit a user to easily verify that a laser diffraction particle sizing instrument is operating within tolerance limit specifications, for example, such that the instrument accuracy is as stated by the manufacturer. The recommended calibration verification method provides a decisive indication of the overall performance of the instrument at the calibration point or points, but it is specifically not to be inferred that all factors in instrument performance are verified. In effect, use of this test method will verify the instrument performance for applications involving spherical particles of known refractive index where the near-forward light scattering properties are accurately modeled by the instrument data processing and data reduction software. The precision and bias limits presented herein are, therefore, estimates of the instrument performance under ideal conditions. Nonideal factors that could be present in actual applications and that could significantly increase the bias errors of laser diffraction instruments include vignetting4 (that is, where light scattered at large angles by particles far away from the receiving lens does not pass through the receiving lens and therefore does not reach the detector plane), the presence of nonspherical particles, the presence of particles of unknown refractive index, and multiple scattering.1.2 This test method shall be used as a significant test of the instrument performance. While the procedure is not designed for extensive calibration adjustment of an instrument, it shall be used to verify quantitative performance on an ongoing basis, to compare one instrument performance with that of another, and to provide error limits for instruments tested.1.3 This test method provides an indirect measurement of some of the important parameters controlling the results in particle sizing by laser diffraction. A determination of all parameters affecting instrument performance would come under a calibration adjustment procedure.1.4 This test method shall be performed on a periodic and regular basis, the frequency of which depends on the physical environment in which the instrumentation is used. Thus, units handled roughly or used under adverse conditions (for example, exposed to dust, chemical vapors, vibration, or combinations thereof) shall undergo a calibration verification more frequently than those not exposed to such conditions. This procedure shall be performed after any significant repairs are made on an instrument, such as those involving the optics, detector, or electronics.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 problems, 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 intended for use in the laboratory or in the field to evaluate the cleanliness of distillate fuels, and liquid biofuels, such as biodiesel and diesel blends. This specific test method and the precision statement applies to off-line analysis.NOTE 5: These PCMs can be used for high pressure on-line applications as well, however the repeatability (r) and reproducibility (R) for on-line application were not established.5.2 An increase in particulate counts can indicate a change in the fuel condition caused for example by contamination during storage or transfer. Potential causes of particulates formation during storage could be “fuel-degradation products,” as described in Specification D975, Appendix X3.5.3 High levels of particles can cause filter blockages (especially when the particles are close in size to the filter porosity rating) and have a serious impact on the life of pumps, injectors, pistons, and other moving parts. Knowledge of particle size in relation to the metallurgy can provide vital information, especially if the hardness of particles is also known from other sources.5.4 This test method specifies a minimum requirement for reporting measurements in particle size bands (A1.2.1). Some specific applications may require measurements in other particle size bands. The particle count from the test should be carefully interpreted by the user as it can potentially over-state risk of abrasive damage or filter blocking due to counting water droplets as well as hard dirt particles.5.5 In situations where there is a requirement for the calibration of the apparatus to be solely in accordance with ISO 11171, Test Methods D7619, IP 565, or IP 577 may be used.1.1 This test method uses specific particle contamination monitors (PCMs) to count and measure the size of dispersed dirt particles, water droplets and other particulates, in middle distillate fuel, in the overall range from 4 µm to 70 µm and in the size bands ≥4 µm, ≥6 µm, ≥14 µm, and ≥30 µm.NOTE 1: The term particle contamination monitor, as used in this test method, is the same as that defined in ISO 21018-4; an instrument that automatically measures the concentrations of particles suspended in a fluid at certain sizes and cannot be calibrated in accordance with ISO 11171 whose output may be as a particle size distribution at limited sizes or as a contamination code.1.2 This test method has interim repeatability precision only, see Section 14 for more information.NOTE 2: ASTM specification fuels falling within the scope of this test method include Specifications: D975, D1655, D3699, D7467, MIL-DTL-83133, MIL-DTL-5624, and distillate grades of D396 and D2880.NOTE 3: For the purposes of this test method, water droplets are counted as particles, and agglomerated particles are detected and counted as a single larger particle. Dirt includes microbial particulates. Although the projected area of a particle is measured, this is expressed as the diameter of a circle for the purposes of this test method. The detector is unable to distinguish between dirt and water particles.NOTE 4: This test method may be used for particle sizes bands up to 70 µm, however the interim repeatability has only been determined for the size bands ≥4 µm, ≥6 µm, and ≥14 µm. All measurements are counts per millilitre.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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