5.1 Manufacturers of carpet need to monitor emissions of VOCs to assess the environmental impact of their products indoors. These results are also used to demonstrate compliance with VOC emission limits for individual VOCs.5.2 These data are also used to understand which VOCs are emitted from a product or material and to measure the magnitude of those emissions.5.3 Emission data may be used to compare different lots of carpet of the same materials of construction, or carpets composed of different materials of construction, in order to develop products with lower emissions and lower potential environmental impact.5.4 This test method should be used in conjunction with practices/guidelines for emissions testing such as Guide D5116, Practice D7143, Practice D7706, ISO 16000-9, and ISO 16000-10. These detail how to select and prepare samples and how and when to carry out emissions tests such that the concentration and profile of vapors in the exhaust air of the emission chamber/cell are representative of the product under test. This test method covers the sampling and analysis of volatile organic compounds in the exhaust gas from the chamber/cell using thermal desorption—compatible sorbent tubes and will provide the necessary analytical consistency to ensure that reproducible data is obtained for the analysis of identical vapor samples by different laboratories.1.1 This test method describes an analytical procedure for identifying and quantifying the masses of individual volatile organic compounds (individual VOCs or IVOCs) that are emitted into a flow of air from carpet specimens and collected on sorbent sampling tubes during emissions testing.1.2 This test method will be used in conjunction with a standard practice for sampling and preparing carpet specimens for emissions testing. If a specific chamber practice is not available for the carpet specimens, this test method should be used in conjunction with approved standard practices for emissions testing and sample preparation.1.3 When used in conjunction with standard practices for carpet specimen preparation and collection of vapor-phase emissions , this test method will provide a standardized means of determining the levels of IVOC in the exhaust stream of the emissions test chamber/cell. If this test method is used with a reliable practice for emissions testing, these IVOC levels can be used to determine the emission rate from a unit quantity (usually surface area) of the sample material under test.1.4 VOCs in the exhaust stream of an emissions test device are collected on thermal desorption tubes packed with a specific combination of sorbents using active (pumped) sampling. (See Practice D6196 for a more general description of vapor collection using pumped sampling onto sorbent tubes.) The samples are analyzed by thermal desorption (TD) with gas chromatography and mass spectrometry detection (GC/MS) and/or flame ionization detection (FID) depending upon the requirements of the specific materials emissions testing/certification protocol.1.5 This test method can be used for the measurement of most GC-compatible organic vapors ranging from the approximate volatility from n-hexane to n-hexadecane (that is, compounds with vapor pressures ranging from 16 kPa to 4 × 10-4 kPa at 25°C). Properties other than a compound’s vapor pressure such as affinity for the sorbent may need to be taken into account. Compounds with vapor pressures outside this range may or may not be quantifiable by this test method. However, qualitative data concerning the identity of a compound(s), outside the stated volatility range for quantitation, may still be useful to the user. This test method can be applied to analytes over a wide concentration range—typically 1 μg/m3 to 1 mg/m3 concentration of vapor in the exhaust air from the emission cell or chamber.1.6 This test method is not capable of quantifying all compounds which are emitted from carpets. See the appropriate test practices/methods for determining other compounds that are not amenable to analysis by gas chromatography (that is, Test Method D5197 for the determination of aldehydes).1.7 Units—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 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.1.9 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 During the process of calibration of a groundwater flow model, each simulation is compared to site-specific information to ascertain the success of previous calibration efforts and to identify potentially beneficial directions for further calibration efforts. Procedures described herein provide guidance for making comparisons between groundwater flow model simulations and measured field data.5.2 This guide is not meant to be an inflexible description of techniques comparing simulations with measured data; other techniques may be applied as appropriate and, after due consideration, some of the techniques herein may be omitted, altered, or enhanced.1.1 This guide covers techniques that should be used to compare the results of groundwater flow model simulations to measured field data as a part of the process of calibrating a groundwater model. This comparison produces quantitative and qualitative measures of the degree of correspondence between the simulation and site-specific information related to the physical hydrogeologic system.1.2 During the process of calibration of a groundwater flow model, each simulation is compared to site-specific information such as measured water levels or flow rates. The degree of correspondence between the simulation and the physical hydrogeologic system can then be compared to that for previous simulations to ascertain the success of previous calibration efforts and to identify potentially beneficial directions for further calibration efforts.1.3 By necessity, all knowledge of a site is derived from observations. This guide does not address the adequacy of any set of observations for characterizing a site.1.4 This guide does not establish criteria for successful calibration, nor does it describe techniques for establishing such criteria, nor does it describe techniques for achieving successful calibration.1.5 This guide is written for comparing the results of numerical groundwater flow models with observed site-specific information. However, these techniques could be applied to other types of groundwater related models, such as analytical models, multiphase flow models, noncontinuum (karst or fracture flow) models, or mass transport models.1.6 This guide is one of a series of guides on groundwater modeling codes (software) and their applications.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 and health practices and determine the applicability of regulatory limitations prior to use.1.8 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.

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5.1 The specific gravity of soil solids is used in calculating the phase relationships of soils, such as void ratio and degree of saturation.5.1.1 The specific gravity of soil solids is used to calculate the density of the soil solids. This is done by multiplying the specific gravity by the density of water at 20°C. The soil solids density is nearly independent of temperature.5.2 The term soil solids is typically assumed to mean naturally occurring mineral particles or soil like particles that are not readily soluble in water. Therefore, the specific gravity of soil solids containing extraneous matter, such as cement, lime, and the like, water-soluble matter, such as sodium chloride, and soils containing matter with a specific gravity less than one, typically require special treatment (see Note 2) or a qualified definition of their specific gravity.NOTE 2: For some soils containing a significant fraction of organic matter, kerosene is a better wetting agent than water and may be used in place of test water for oven-dried specimens. Kerosene is a flammable liquid that must be used with extreme caution. This standard should not be used when using kerosene as the test fluid.5.3 The balances, pycnometer sizes, and specimen masses are specified to obtain test results reportable to four significant digits.NOTE 3: The quality of the result produced by these test methods is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of these test methods are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.AbstractThese test methods cover the determination of the specific gravity of soil solids passing a sieve by means of a water pycnometer. Soil solids for these test methods do not include solids which can be altered by these methods, contaminated with a substance that prohibits the use of these methods, or are highly organic soil solids, such as fibrous matter which floats in water. Procedures for moist specimens such as organic soils, highly plastic fine grained soils, tropical soils, and soils containing halloysite and oven-dry specimens are provided. The apparatus is comprised of water pycnometer which shall be a stoppered flask, stoppered iodine flask, or volumetric flask; balance; drying oven; thermometer; dessicator; a system for entrapped air removal which shall be a hot plate or Bunsen burner or a vacuum pump or water aspirator; insulated container; non-corrosive smooth surface funnel; pycnometer filling tube with lateral vents; sieve; and blender with mixing blades. The specific gravity of the soil solids at the test temperature shall be calculated from the density of the soil solids and the density of water at the test temperature or from the mass of the oven dry soil solids; mass of pycnometer, water, and soil solids at the test temperature; and mass of the pycnometer and water at the test temperature. Precision and bias shall be determined to judge for the acceptability of the test results.1.1 These test methods cover the determination of the specific gravity of soil solids that pass the 3/8-in. (9.5-mm) or smaller sieve by means of the water displacement method. When the total sample contains larger particles, it is separated into a coarser and finer portion using a 3/8-in. (9.5-mm) or No. 4 (4.75-mm) or finer sieve. Separation on the No. 4 sieve is the referee method. Test Method C127 shall be used to obtain the specific gravity of the coarser portion. The D854 test methods shall be used to obtain the specific gravity of the finer portion. The total sample specific gravity is computed from the two portions as described in 12.5.1.1.1 These test methods do not apply to solids which can be altered by these methods, contaminated with a substance that prohibits the use of these methods, or are highly organic, such as fibrous matter which floats in water (see Note 1).NOTE 1: Test Method D5550 may be used to determine the specific gravity of soil solids having solids, which readily dissolve in water or float in water, or where it is impracticable to use water.1.2 This standard provides two methods for performing the specific gravity test. The method to be used shall be specified by the requesting authority, except when testing the types of soils listed in 1.2.1.1.2.1 Method A—Procedure for Moist Specimens, described in 11.1. This procedure is the preferred method. Method A shall be used for organic soils; highly plastic, fine-grained soils; tropical soils; and soils containing halloysite.1.2.2 Method B—Procedure for Oven-Dry Specimens, described in 11.2. This procedure requires less time and may be used for clean sands.1.3 Units—The values stated in SI units are to be regarded as standard, except the sieve designations. The sieve designations are identified using the “alternative” system in accordance with Practice E11, such as 3-in. and No. 200, instead of the “standard” designation of 75-mm and 75-µm, respectively. Reporting of test results in units other than SI shall not be regarded as non-conformance with this test method. The use of balances or scales recording pounds of mass (lbm) shall not be regarded as nonconformance with this standard.1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this test method.1.4.1 The procedures used to specify how data are collected/recorded and calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of these test methods to consider significant digits used in analysis methods for engineering design.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. Glassware under vacuum has the potential for implosion. Proper personal protective equipment shall be used at all times. See Section 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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4.1 This test will provide information on the ability of coatings applied to pipe to resist cracking, disbonding, or other mechanical damage as a result of bending. Because the test is applied to coated pipe from commercial production, the results can be directly used in the selection of similar materials for service. The test also has application as a quality control method when variations in coating application or material formulation will affect bending performance.1.1 This test method covers the specific determination of the effect of short-radius bends on coatings applied to 33.4-mm (1-in. nominal) diameter pipe.1.2 The values stated in SI units to three significant decimals are to be regarded as the 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, 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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1.1 This test method describes the procedures required to carry out a pure-culture study for evaluating the biodegradation of degradable plastics in submerged culture under aerobic conditions. Degradation will be evaluated by weight loss, tensile strength loss, percent-elongation loss and changes in molecular-weight distribution. 1.2 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 Riprap and armor material are composed of pieces of natural rock or manmade material that are placed on construction projects, shorelines, streambeds, bridge abutments, pilings and other structures to minimize the effects of erosion. The ability of rock or manmade material to withstand deterioration from weathering affects both the effectiveness of the project and its cost. The specific gravity and absorption provide useful information that can be used in evaluating possible deterioration of rock or manmade material.5.2 Test specimens equal in size to the proposed design size would provide the best correlations between laboratory tests and actual field performance; however, this is usually neither practical nor economically feasible.5.3 This test method has been used to evaluate different types of rocks and manmade material. There have been rare occasions when test results have provided data that have not agreed with the durability of rock or manmade material under actual field conditions.5.4 The results of this test is not to be used as the sole basis for determination of durability, but should be used in conjunction with the results of other tests.Note 1—The quality of the result produced by this standard is dependent upon the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluation some of those factors1.1 This test method covers the determination of the rapid specific gravity of rock or man-made materials for erosion control.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.1.3 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this standard.1.3.1 For purposes of comparing measured or calculated value(s) with specified limits, the measured or calculated value(s) shall be rounded to the nearest decimal or significant digits in the specified limits.1.3.2 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analytical methods for engineering design.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 and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 Specific gravity, apparent, may be used as a qualitative test in establishing the identity of a chemical. It may be used to calculate the volume occupied by a product whose weight is known, or to calculate the weight of a product from its volume. It may be used to determine the composition of binary mixtures of pure chemicals. In the case of most refined industrial chemicals specific gravity, apparent, is of minimal value in defining quality, although it may detect gross contamination.4.2 Of the two test methods described, the pycnometer method (Test Method B, 1.1.2) is the most accurate and precise. For this reason it is the preferred method in case of disputes. The hydrometer method (Test Method A, 1.1.1) is the least accurate and precise, but it is also the simplest and fastest to perform and is often entirely satisfactory for many purposes. If the sample is too viscous to permit the hydrometer to float freely, the pycnometer test method should be used.1.1 These test methods cover the determination of the specific gravity, apparent, of liquid industrial chemicals. Two test methods are covered as follows:1.1.1 Test Method A, specific gravity, apparent, by means of a hydrometer.1.1.2 Test Method B, specific gravity, apparent, by means of a pycnometer.NOTE 1: Test Method D4052 describes an instrumental procedure.1.2 In common usage the term specific gravity, apparent, is understood to mean specific gravity.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in these test methods with the exception of Fahrenheit (°F) in 5.1 as an example of a possible industrial specification unit.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. For specific hazard statements, see Sections 8 and 16.1.5 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 Measurement of specific gravity is a tool for determining the degree of maturation of a ceramic body.1.1 This test method covers the determination of specific gravity of fired ceramic whiteware materials under prescribed conditions.NOTE 1: This test method is not applicable to materials attacked by water.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.3 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 provisional test method covers the determination of maximum specific gravity of loose bituminous mixtures, as defined in Terminology E 1547, by the vacuum sealing method.1.2 This method can be used with 100 and 150 mm diameter compacted bituminous laboratory and field specimens.1.3 The bulk specific gravity of the compacted bituminous mixtures may be used in calculating the unit weight of the mixture.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 and health practices and determine the applicability of regulatory requirements prior to use.Note 1—Provisional standards require only subcommittee consensus and are published for a limited time of two years. The provisional process was used because of the immediate need for this method to be used in testing pavement mixtures with open graded design, mixtures that readily absorb water and mixtures that allow water to rapidly penetrate and drain out.

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1.1 This provisional test method covers the determination of maximum specific gravity of and density of uncompacted bituminous paving mixtures at 25°C (77°F).1.2 The values stated in SI units are to be regarded as the standard. The other units given may be approximate and are given to help the user interpret units on available standard equipment used with this provisional test method.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.Note 1—Provisional standards require only subcommittee consensus and are published for a limited time of two years. The provisional process was used because agencies and private organizations have an immediate need for a method that will save time and accurately reduce water absorption by absorptive mixes, eliminating the need for post vacuum "dry back" correction and stripping. This method provides a quick way to test loose bitminous mixtures for maximum specific gravity.

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5.1 The specific gravity or density of a solid is a property that is conveniently measured to identify a material, to follow physical changes in a sample, to indicate degree of uniformity among different sampling units or specimens, or to indicate the average density of a large item.5.2 Changes in density of a single material are due to localized differences in crystallinity, loss of plasticizer, absorption of solvent, or to other causes. It is possible that portions of a sample differ in density because of their differences in crystallinity, thermal history, porosity, and composition (types or proportions of resin, plasticizer, pigment, or filler).5.3 Density is useful for calculating strength-weight and cost-weight ratios.1.1 These test methods describe the determination of the specific gravity (relative density) and density of solid plastics in forms such as sheets, rods, tubes, or molded items.1.2 Two test methods are described:1.2.1 Test Method A—For testing solid plastics in water, and1.2.2 Test Method B—For testing solid plastics in liquids other than water.1.3 The values stated in SI units are to be regarded as the standard.1.4 Warning—Mercury has been designated by many regulatory agencies as a hazardous substance that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Use caution when handling mercury and mercury-containing products. See the applicable product Safety Data Sheet (SDS) for additional information. The potential exists that selling mercury or mercury-containing products, or both, is prohibited by local or national law. Users must determine legality of sales in their location.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.NOTE 1: This standard is not equivalent to ISO 1183–1 Method A. This test method provides more guidelines on sample weight and dimension. ISO 1183-1 allows testing at an additional temperature of 27 ± 2°C.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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Sulfur can be a catalyst poison in the aromatic chemical manufacturing process. This test method can be used to monitor the amount of sulfur in aromatic hydrocarbons. This test method may also be used as a quality control tool and in setting specifications for sulfur determination in finished products.1.1 This test method covers the determination of sulfur in aromatic hydrocarbons, their derivatives and related chemical having typical sulfur concentrations from 0.005 to 10 mg/kg.1.2 This test method may be extended to higher concentrations by dilution.1.3 This test method is applicable to aromatic hydrocarbons such as benzene, toluene, cumene, p-xylene, o-xylene, cyclohexane, phenol, cresols, xylenols, and other aromatic or oxygenated aromatic compounds.1.4 The following applies to all specified limits in this test method: for purposes of determining conformance with this standard, an observed value or a calculated value shall be rounded off to the nearest unit in the last right-hand digit used for expressing the specification limit in accordance with the rounding-off method of Practice E 29.1.5 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. specific precautionary statements are given in 7./5, 76. 8, 11.4.

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5.1 Specific strength is a measure of the ability of a fiber matrix product to withstand force applied by a tensile machine and is useful to understand in order to produce quality products. Specific strength is frequently related to the matrix density, fiber quality, fiber length and chemistry and can be used as a measurement for quality assurance or quality control, or both requirements.5.2 This method may not be applicable to all hydraulically applied fiber matrix products due to variations in product chemistry.NOTE 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This standard provides a quantitative test method to determine the specific strength of hydraulically applied fiber matrix products using dry and wet preparation methods in a laboratory setting. This method is designed for use as an index test for product quality assurance or quality control, or both to comply with manufacturing requirements. This test method is not indicative of product performance in the field.1.2 Units—The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only and are not considered standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard.1.3 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this test method.1.3.1 The procedures used to specify how data are collected/recorded and calculated in the standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of these test methods to consider significant digits used in analysis methods for engineering data.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 Both suppliers and users of metals can benefit from knowledge of the surface area of these materials. Results of many intermediate and final processing steps are controlled by, or related to, specific surface area of the metal. The performance of many sintered or cast metal structures may be predicted from the specific surface area of the starting metal powder, or all or a portion of the finished piece.1.1 This test method covers determination of surface area of metal powders. The test method specifies general procedures that are applicable to many commercial physical adsorption instruments. The method provides specific sample outgassing procedures for listed materials. It includes additional general outgassing instructions for other metals. The multipoint equation of Brunauer, Emmett, and Teller (BET),2 along with the single point approximation of the BET equation, forms the basis for all calculations.1.2 This test method does not include all existing procedures appropriate for outgassing metallic materials. The procedures included provided acceptable results for samples analyzed during interlaboratory testing. The investigator shall determine the appropriateness of listed procedures.1.3 Units—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 State all numerical values in terms of SI units, unless specific instrumentation software reports surface area using alternate units. In this case, present both reported and equivalent SI units in the final written report. Many instruments report surface area as m2/g, instead of using correct SI units (m2/kg).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 The resistivity of a liquid is a measure of its electrical insulating properties under conditions comparable to those of the test. High resistivity reflects low content of free ions and ion-forming particles, and normally indicates a low concentration of conductive contaminants.1.1 This test method covers the determination of specific resistance (resistivity) applied to new electrical insulating liquids, as well as to liquids in service, or subsequent to service, in cables, transformers, circuit breakers, and other electrical apparatus.1.2 This test method covers a procedure for making referee tests with dc potential.1.3 When it is desired to make routine determinations requiring less accuracy, certain modifications to this test method are permitted as described in Sections 19 – 26.1.4 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. See 17.4.3 for a specific warning statement.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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