5.1 Certain gases have excellent dielectric and electric arc interruption characteristics which make their use in electrical installations very desirable.5.2 Water content, as the test parameter, is of great importance in determining the dielectric effectiveness of the gas. Under certain conditions, water may condense and become a conducting liquid resulting in a catastrophic dielectric breakdown of the insulation. The water content of these insulating gases as expressed by dew point is listed in Specifications D1933, D2472, and D3283.5.3 Once the dew point is determined, a conversion to moisture content may be performed using Table 1. Once moisture content is known, the lowest temperature at which gas insulated equipment can be safely operated can usually be determined by reviewing manufacturers' specifications for the equipment.(A) Vapor pressures in atmospheres at various dew points can be obtained by dividing the values for “volume percent'' in this table by 100. Calculations for this table were made by using the International Critical Table values for the vapor pressure of ice and liquid water. The vapor pressure of liquid water was used for values from 50 to 0°C. The vapor pressure of ice was used from 0 to − 81°C.5.4 The dew point of the test gas is independent of the gas temperature but does depend on its pressure. Many moisture measurement test instruments are sensitive to pressure, and display moisture values at the instrument inlet pressure and not necessarily at the pressure of the system being sampled. It is therefore important to account for this condition to avoid serious measurement errors.1.1 These test methods describe the determination of the water vapor content of electrical insulating gases by direct or indirect measurement of the dew point and the calculation of the water vapor content.1.2 The following four test methods are provided:1.2.1 Method A describes the automatic chilled mirror method for measurement of dew point as low as − 73°C (−99°F).1.2.2 Method B describes the manual chilled mirror or dew cup method for measurement of dew point as low as − 73°C (−99°F).1.2.3 Method C describes the adiabatic expansion method for measurement of dew point as low as − 62°C (−80°F).1.2.4 Method D describes the capacitance method for measurement of dew point as low as − 110°C (−166°F).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. For specific warnings, see 8.1.1, 9.2, 10.1.2 and 10.2.5.

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5.1 Accurate quantitative compositional information on hydrocarbon types can be useful in determining the effects of processes in the production of various finished fuels. Producers may require additional determinations such as n-paraffins, i-paraffins, naphthenes, and aromatics for process optimization. This information also may be useful for indicating the quality of fuels and for assessing the relative combustion properties of finished fuels. This test method can be used to make such determinations.1.1 This test method covers the quantitative determination of total n-paraffins, total i-paraffins, total naphthenes (cycloparaffins), total one ring (1R) and total two ring plus (2R+) aromatic hydrocarbons in hydrocarbon liquids having a boiling point between 36 °C and 343 °C by GCxGC (flow modulated comprehensive two-dimensional gas chromatography). The method has been applied to aviation turbine fuels and is applicable to other low olefinic fuels in the stated boiling point range.1.2 This test method has an interim precision. An expanded full interlaboratory study is to be completed in <5 years. The test method working concentration ranges in mass percent for which the interim precision has been determined are as follows:Hydrocarbon Type Lower limit(mass percent) Upper limit(mass percent)Total i-paraffins 22.0 24.3Total n-paraffins 19.0 21.9Total naphthenes (cycloparaffins) 34.3 36.7Total one ring aromatics 18.7 21.8Total two ring plus aromatics 0.5 1.91.3 This test method is applicable to other group type concentration ranges, to other hydrocarbon types such as selected individual components, for example, benzene, toluene, or n-paraffins by carbon number, or to other hydrocarbon streams; however, precision has not been determined at this time. A future ILS will include a variety of sample types and extend the reporting.1.4 This test method is not intended to determine unsaturated hydrocarbons, such as olefins, content which may interfere with the cycloparaffins; this test method is applicable to samples with < 1% by mass total olefins as determined by D1319.1.5 This test method is not intended to determine FAME (fatty acid methyl esters). For such applications, Test Method D7797, IP 585, or equivalent test methods are available.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard test method does not mandate or describe a specific software package for data processing and display. Any commercially available GCxGC software used for data processing and display shall meet the requirements for the calculation of the results. Appendix X1 provides some guidelines.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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3.1 Test methods using suitable ring-type specimens4 are the preferred methods of determining the basic magnetic properties of a material caused by the absence of demagnetizing effects and are well suited for specification acceptance, service evaluation, and research and development. 3.2 Provided the test specimen is representative of the bulk material as is usually the case for thin strip and wire, this test is also suitable for design purposes. 3.3 When the test specimen is not necessarily representative of the bulk material such as a ring machined from a large forging or casting, the results of this test method may not be an accurate indicator of the magnetic properties of the bulk material. In such instances, the test results when viewed in context of past performance history will be useful for judging the suitability of the current material for the intended application. 1.1 This test method covers dc testing for the determination of basic magnetic properties of materials in the form of ring, toroidal, link, double-lapped Epstein cores, or other standard shapes which may be cut, stamped, machined, or ground from cast, compacted, sintered, forged, or rolled materials. It includes tests for determination of the normal magnetization curve and hysteresis loop taken under conditions of steep wavefront reversals of the direct-current magnetic field strength. 1.2 This test method shall be used in conjunction with Practice A34/A34M. 1.3 This test method is suitable for a testing range from very low magnetic field strength up to 200 or more Oe [15.9 or more kA/m]. The lower limit is determined by integrator sensitivity and the upper limit by heat generation in the magnetizing winding. Special techniques and short duration testing may extend the upper limit of magnetic field strength. 1.4 Testing under this test method is inherently more accurate than other methods. When specified dimensional or shape requirements are observed, the measurements are a good approximation to absolute properties. Test accuracy available is primarily limited by the accuracy of instrumentation. In most cases, equivalent results may be obtained using Test Method A773/A773M or the test methods of IEC Publication 60404-4. 1.5 This test method permits a choice of test specimen to permit measurement of properties in any desired direction relative to the direction of crystallographic orientation without interference from external yoke systems. 1.6 The symbols and abbreviated definitions used in this test method appear in Fig. 1 and Sections 5, 6, 9, and 10. For the official definitions see Terminology A340. FIG. 1 Basic Circuit Using Ring-Type Cores Note 1:  A1—Multirange ammeter, main-magnetizing current circuit A2—Multirange ammeter, hysteresis-current circuit N1—Magnetizing (primary) winding N2—Flux-sensing (secondary) winding F—Electronic integrator R1—Main current control rheostat R2—Hysteresis current control rheostat S1—Reversing switch S2—Shunting switch for hysteresis current control rheostat 1.7 Warning—Mercury has been designated by EPA and many state agencies as a hazardous material that can cause central nervous system, kidney, and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Material Safety Data Sheet (MSDS) for details and EPA’s website (http://www.epa.gov/mercury/faq.htm ) for additional information. Users should be aware that selling mercury or mercury-containing products, or both, in your state may be prohibited by state law. 1.8 The values stated in either customary (cgs-emu and inch-pound) units or SI units are to be regarded separately as standard. Within this test method, the SI units are shown in brackets except for the sections concerning calculations where there are separate sections for the respective unit systems. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with this method. 1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The freezing point of an engine coolant indicates the coolant freeze protection.5.2 The freezing point of an engine coolant may be used to determine the approximate glycol or glycerin content, provided the glycol type is known.1.1 This test method covers the determination of the freezing point of an aqueous engine coolant solution in the laboratory.NOTE 1: Where solutions of specific concentrations are to be tested, they shall be prepared from representative samples as directed in Practice D1176. Secondary phases separating on dilution need not be separated.NOTE 2: These products may also be marketed in a ready-to-use form (prediluted).1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.3 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 establishes standardized tests for the performance evaluation of sensor-based continuous instruments for ambient air quality measurements. Public and private air monitoring interests have manifested themselves as a driving force for the deployment of air quality sensors and instruments to quantify air pollutant concentrations in communities, around schools, around industrial facilities, and elsewhere. Users of air quality sensors require information on the performance and limitations of these devices so that informed decisions regarding their suitability for various purposes can be determined. This practice describes both laboratory and field tests that provide information on candidate instrument repeatability, sensitivity, linearity, cross-interferences, drift and comparability with more costly instruments typically used by entities such as government agencies. The air quality sensors are first evaluated in a laboratory chamber by comparing their response to a reference instrument and challenging the gas sensors with interferents. The sensors are then deployed outdoors for field testing at two sites with different climates against reference air quality instruments. This practice is intended to be referenced in standards and codes that establish minimum performance quality for sensor-based ambient outdoor air monitoring.5.2 This practice is intended for air quality sensors that measure one or more of the criteria pollutants in ambient air (ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, PM10 and PM2.5) that can be operated in outdoor environments and can log a concentration reading. It is not intended for devices or transducers that require additional enclosures for deployment outdoors or post-processing to convert their output signal into a pollutant concentration reading.5.3 It is anticipated that the main users of this practice will be manufacturers, developers, and distributors of outdoor air quality sensors, air quality agencies, and environmental consultants.1.1 This practice establishes standardized tests for the performance evaluation of sensor-based continuous instruments for ambient outdoor air quality measurements. It describes both laboratory and field tests that provide information on candidate sensor repeatability, sensitivity, linearity, cross-interferences, drift, and comparability against reference instruments.1.2 This practice does not apply to sensors or instruments that remotely measure atmospheric pollutants using open path, lidar, or imaging technology.1.3 The evaluation procedures contained in this practice are for sensors that alone or in combination measure outdoor criteria pollutants in ambient air: particulate matter (PM2.5 and PM10), sulfur dioxide (SO2), ozone (O3), carbon monoxide (CO), or nitrogen dioxide (NO2) at concentrations that are relevant to public health.1.4 Testing is to be performed by a competent entity able to demonstrate that it operates in conformity with internationally accepted test laboratory quality standards such as ISO/IEC 17025.1.5 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 In general, with materials of these types, softening does not take place at a definite temperature. As the temperature rises, these materials gradually change from brittle or exceedingly thick and slow-flowing materials to softer and less viscous liquids. For this reason, the determination of the softening point must be made by a fixed, arbitrary, and closely defined method if the results obtained are to be comparable.3.2 In these test methods, the softening point is defined as the temperature at which a disk of the sample held within a horizontal ring is forced downward a distance of 25.4 mm (1 in.) under the weight of a steel ball as the sample is heated at 5 °C/min in a water, glycerin, silicone oil, ethylene glycol/water or glycerin/water bath.3.3 The automatic method was chosen to be the reference method because a round robin demonstrated that it gave more precise results than the manual method.1.1 These test methods are intended for determining the softening point of resins (including rosin and terpene resins) and similar materials by means of the ring-and-ball apparatus.NOTE 1: For testing asphalts, tars, and pitches, see Test Method D36.1.1.1 Test method using the automated ring and ball softening point apparatus is the reference method and the test method using the manual ring and ball method is an alternative method.1.2 The values stated in SI units 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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5.1 The first-peak strength characterizes the flexural behavior of the fiber-reinforced concrete up to the onset of cracking, while residual strengths at specified deflections characterize the residual capacity after cracking. Specimen toughness is a measure of the energy absorption capacity of the test specimen. The appropriateness of each parameter depends on the nature of the proposed application and the level of acceptable cracking and deflection serviceability. Fiber-reinforced concrete is influenced in different ways by the amount and type of fibers in the concrete. In some cases, fibers may increase the residual load and toughness capacity at specified deflections while producing a first-peak strength equal to or only slightly greater than the flexural strength of the concrete without fibers. In other cases, fibers may significantly increase the first-peak and peak strengths while affecting a relatively small increase in residual load capacity and specimen toughness at specified deflections.5.2 The first-peak strength, peak strength, and residual strengths determined by this test method reflect the behavior of fiber-reinforced concrete under static flexural loading. The absolute values of energy absorption obtained in this test are of little direct relevance to the performance of fiber-reinforced concrete structures since they depend directly on the size and shape of the specimen and the loading arrangement.5.3 The results of this test method may be used for comparing the performance of various fiber-reinforced concrete mixtures or in research and development work. They may also be used to monitor concrete quality, to verify compliance with construction specifications, obtain flexural strength data on fiber-reinforced concrete members subject to pure bending, or to evaluate the quality of concrete in service.5.4 The results of this standard test method are dependent on the size of the specimen.NOTE 5: The results obtained using one size molded specimen may not correspond to the performance of larger or smaller molded specimens, concrete in large structural units, or specimens sawn from such units. This difference may occur because the degree of preferential fiber alignment becomes more pronounced in molded specimens containing fibers that are relatively long compared with the cross-sectional dimensions of the mold. Moreover, structural members of significantly different thickness experience different maximum crack widths for a given mid-span deflection with the result that fibers undergo different degrees of pull-out and extension.1.1 This test method evaluates the flexural performance of fiber-reinforced concrete using parameters derived from the load-deflection curve obtained by testing a simply supported beam under third-point loading using a closed-loop, servo-controlled testing system.1.2 This test method provides for the determination of first-peak and peak loads and the corresponding stresses calculated by inserting them in the formula for modulus of rupture given in Eq 1. It also requires determination of residual loads at specified deflections, the corresponding residual strengths calculated by inserting them in the formula for modulus of rupture given in Eq 1 (see Note 1). It provides for determination of specimen toughness based on the area under the load-deflection curve up to a prescribed deflection (see Note 2) and the corresponding equivalent flexural strength ratio.NOTE 1: Residual strength is not a true stress but an engineering stress computed using simple engineering bending theory for linear elastic materials and gross (uncracked) section properties.NOTE 2: Specimen toughness expressed in terms of the area under the load-deflection curve is an indication of the energy absorption capability of the particular test specimen, and its magnitude depends directly on the geometry of the test specimen and the loading configuration.1.3 This test method utilizes two preferred specimen sizes of 100 mm by 100 mm by 350 mm [4 in. by 4 in. by 14 in.] tested on a 300 mm [12 in.] span, or 150 mm by 150 mm by 500 mm [6 in. by 6 in. by 20 in.] tested on a 450 mm [18 in.] span. A specimen size different from the two preferred specimen sizes is permissible.1.4 Units—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.1.5 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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