4.1 This practice is designed for use by the oil processor or research laboratory for evaluation by a trained sensory panel, or for use by quality control (QC) and quality assurance (QA) personnel for sampling from a tank truck, car, or any other bulk transportation container, or by both.4.2 The consistent use of this practice will provide representative samples for all sensory, chemical and physical analyses and will protect the oil from oxidation.4.3 The objective of this practice is to ensure that the sample is representative of the sample source from the time of sampling until the time of evaluation and to protect oil quality during that time.4.4 This practice addresses neither evaluation and scaling techniques, nor the sampling, handling, and preparing of solid fats.1.1 This practice covers the recommended procedures for bulk sampling, handling, and preparing edible vegetable oil (liquid at room temperature) prior to sensory evaluation.1.2 This practice is consistent with the background information presented in ASTM STP 433, ASTM Manual 26, and ASTM STP 758. These should be consulted for supplemental guidance.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.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 Uranium hexafluoride is normally produced and handled in large (typically 1- to 20-ton) quantities and must, therefore, be characterized by reference to representative samples. The quantities involved, physical properties, chemical reactivity, and hazardous nature of UF6 are such that for representative sampling, specially designed equipment must be used and operated in accordance with the most carefully controlled and stringent procedures. This practice indicates appropriate principles, equipment, and procedures currently in use for bulk sampling of liquid UF6. It is used by UF6 converters, enrichers, and fuel fabricators to review the effectiveness of existing procedures or as a guide to the design of equipment and procedures for future use.5.2 It is emphasized that this practice is not meant to address conventional or nuclear criticality safety issues.1.1 This practice covers methods for withdrawing representative samples of liquid uranium hexafluoride (UF6) from bulk quantities of the material. Such samples are then prepared for further analytical testing in accordance with Practices C1689 and C1346. Multiple different methods are used for determining compliance with the applicable commercial specification, for example Specifications C787 and C996. Methods used for compliance to each of these standards can be found in the Referenced Documents section of each respective specification.1.2 It is assumed that the bulk liquid UF6 being sampled comprises a single quality and quantity of material. This practice does not address any special additional arrangements that might be required for taking proportional or composite samples. When the sampled bulk material is being added to UF6 residues already in a container (“heels recycle”) additional arrangements are required to avoid cross contamination of the bulk UF6, these are addressed in Specifications C787 and C996.1.3 The number of samples to be taken, their nominal sample weight, and their disposition shall be agreed upon between the parties.1.4 The scope of this practice does not include provisions for preventing criticality incidents.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 Noble metal coatings, particularly gold or palladium, are often specified for the contacts of separable electrical connectors and other devices. Electrodeposits are the form of gold or palladium which is most used on contacts, although gold and palladium are also employed as clad metal and as weldments on the contact surface. The intrinsic nobility of gold and to a certain extent palladium enables them to resist the formation of insulating films that could interfere with reliable contact operation.5.2 In order that the nobility of gold be assured, porosity, cracks, and other defects in the coating that expose base metal substrates and underplates must be minimal or absent, except in those cases where it is feasible to use the contacts in structures that shield the surface from the environment or where corrosion inhibiting surface treatments for the deposit are employed. The level of porosity in the coating that may be tolerable depends on the severity of the environment to the underplate or substrate, design factors for the contact device like the force with which it is mated, circuit parameters, and the reliability of contact operation that it is necessary to maintain. Also, when present, the location of pores on the surface is important. If the pores are few in number or are outside of the zone of contact of the mating surfaces, their presence can often be tolerated.5.3 Methods for determining pores on a contact surface are most suitable if they enable their precise location and numbers to be determined. Contact surfaces are often curved or irregular in shape, and testing methods should be suitable for them. In addition, the severity of porosity-determining tests may vary from procedures capable of detecting all porosity to procedures that detect only gross defects. The test method in this document is generally regarded as severe.5.4 The relationship of porosity levels revealed by particular tests to contact behavior must be made by the user of these tests through practical experience or judgment. Thus, absence of porosity in the coating may be a requirement for some applications, while a few pores in the contact zone may be acceptable for others.5.5 This test method is capable of detecting porosity or other defects in gold or palladium coatings that could participate in substrate corrosion reactions. In addition, it can be used on contacts having complex geometry such as pin-socket contacts (although difficulty may be experienced in inspecting deep recesses).1.1 This test method covers equipment and techniques for determining porosity in noble metal coatings, particularly electrodeposits and clad metals used on electrical contacts.1.2 The test method is designed to show whether the porosity level is less or greater than some value which by experience is considered by the user to be acceptable for the intended application.1.3 Other porosity testing methods are outlined in Guide B765. Detailed critical reviews of porosity testing are also available.2 Other porosity test methods are B735, B741, B799, and B809.1.4 The values stated in SI units are to be regarded as standard. The values in parentheses are for information only.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 become familiar with all hazards including those identified in the appropriate Material Safety Data Sheet (MSDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Sections 7 and 8.1.6 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 The electrical resistivity of a concrete is the opposition to the movement of ions under an applied electric field. The electrical conductivity of a concrete is a measure of how readily the ions in the pore solution can be transported through the concrete under an applied electric field (the higher the conductivity, the greater the rate of transport). The electrical resistivity or conductivity is a material property that depends upon the pore volume, the pore structure (size and connectivity), the pore solution composition, the degree of saturation of the concrete specimen, and the specimen’s temperature. Concrete mixture characteristics that are known to affect concrete electrical resistivity, as well as resistance to chloride ion penetration, include water-cementitious materials ratio, pozzolans, slag cement, the presence of polymeric admixtures, air-entrainment, aggregate type, aggregate volume fraction, degree of consolidation, curing method, and age.5.2 The bulk electrical resistivity of concrete is the inverse of its bulk electrical conductivity. Bulk electrical conductivity can also be measured by Test Method C1760, which uses the apparatus described in Test Method C1202. This test method, however, uses apparatus specifically designed to measure bulk conductivity or bulk resistivity.5.3 The purpose of conditioning in a simulated pore solution is to bring the specimen to a level of near complete saturation of the capillary and gel pores. When comparing two different concrete specimens, it is important to condition both specimens as close as possible to a comparable saturation state, using the same solution for conditioning, so that values can be compared in a meaningful way. This is particularly true for using the measured resistivity or conductivity, along with other information, to estimate the diffusivity.5.4 The bulk electrical resistivity or conductivity of concrete can provide a rapid indication of its resistance to chloride ion penetration and resistance to penetration of other fluids. Resistivity or conductivity measurements have shown good correlations with other electrical indication tests including Test Method C1202 (1, 2, 3).6 Bulk electrical resistivity results have shown good correlation with bulk diffusion determined using Test Method C1556 on companion molded cylinders from the same concrete mixtures (4).1.1 This test method covers the determination of the bulk electrical resistivity or conductivity of molded specimens or cored sections of hardened concrete after immersion in water saturated with a simulated pore solution in order to provide a rapid indication of its resistance to the penetration of fluids and dissolved aggressive ions.1.2 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard. If required results obtained from another standard are not reported in the same system of units as used by this standard, it is permitted to convert those results using the conversion factors found in the SI Quick Reference Guide.21.3 The text of this standard references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of 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. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.)3 For specific warning statement see 8.1.2.1.5 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 Apparent porosity, water absorption, apparent specific gravity, and bulk density are primary properties of refractory shapes. These properties are widely used in the evaluation and comparison of product quality and as part of the criteria for selection and use of refractory products in a variety of industrial applications. These test methods are used for determining any or all of these properties and are particularly useful for testing hydratable products.3.2 These test methods are primary standard methods that are suitable for use in quality control, research and development, establishing criteria for and evaluating compliance with specifications, and providing data for design purposes.3.3 Fundamental assumptions inherent in these test methods are:3.3.1 The test specimens conform to the requirements for size, configuration, and original faces,3.3.2 The open pores of the test specimens are fully impregnated with liquid during the vacuum-pressure treatment, and3.3.3 The blotting of the saturated test specimens is performed as specified in a consistent and uniform manner to avoid withdrawing liquid from the pores.3.3.4 Deviation from any of these assumptions adversely affects the test results.3.4 In laboratory studies involving castable specimen, a bias was noted between formed 2 in. by 2 in. by 2 in. (50 mm by 50 mm by 50 mm) and specimens quartered from larger 9 in. by 4.5 in. by 2.5 in. (228 mm by 114 mm by 64 mm) cast specimens. Additionally, an error in the apparent porosity determination was found on castables whenever the specimens were heated to 1500 °F (816 °C) and then exposed to water as a saturation media. The error was attributed to reactivity of cement with water and subsequent re-hydration of cement phases. The higher the cement level of the castable, the greater the error noted. It was concluded that an error in porosity values could occur for refractory materials having a potential to form hydrated species with water. Testing under the same conditions in kerosene produced results that were believed to be more accurate, but the data suggested that the kerosene might not have saturated the open pores of cast specimen as readily as water.33.5 Certain precautions must be exercised in interpreting and using results from these test methods. All four property values are interrelated by at least two of the three base data values generated during testing. Thus, an error in any base data value will cause an error in at least three of the property values for a given test specimen. Certain of the properties, that is, apparent specific gravity and bulk density, are functions of other factors such as product composition, compositional variability within the same product, impervious porosity, and total porosity. Generalizations on or comparisons of property values should be judiciously made between like products tested by these test methods or with full recognition of potentially inherent differences between the products being compared or the test method used.3.6 When a liquid other than water is used, such as types of kerosene or mineral spirits, specific gravity must be known by either determination or monitoring on a controlled basis. Specific gravity will change due to different grades of liquids, evaporation, or contamination with dirt or foreign material. The test should not be run if the liquid becomes dirty, foamy, or changes color, because foreign particles can block pores and prevent impregnation of the sample.1.1 These test methods cover the determination of the following properties of refractory shapes:1.1.1 Apparent porosity,1.1.2 Liquid absorption,1.1.3 Apparent specific gravity, and1.1.4 Bulk density.1.2 These test methods are applicable to all refractory shapes except those that chemically react with both water and mineral spirits. When testing a material capable of hydration or other chemical reaction with water but which does not chemically react with mineral spirits, mineral spirits is substituted for water and appropriate corrections for the density differences are applied when making calculations.1.3 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3.1 Exception—The apparatus used in this standard is only available in SI units.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.NOTE 1: Test Methods C20 cover procedures for testing properties of refractories that are not attacked by water.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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