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The results obtained by this test method are useful as guides in determining the tendency of a water-based metalworking coolant to produce foam under low shear conditions. No correlation with changes in heat transfer, pumpability, or other factors affected by foam is intended. The foam generated by any given industrial process depends on the method by which the foam is generated and may not be directly proportional to that produced by this controlled laboratory test method. Further, the foam generated at the specified test temperature will not necessarily predict the foaming tendency of the liquid (that is, metalworking coolant) at some other use temperature.1.1 This test method covers the measurement of the increase in volume of a low-viscosity aqueous liquid (less than 3 cSt at 40°C) due to its tendency to foam under low shear conditions. Note 1 - Foam under high shear is covered by Test Method D 3519 which uses a commercial blender.<>1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only.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 safety information, see 7.13.

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4.1 This guide defines the meaning of a representative sample, as well as the attributes the sample(s) needs to have in order to provide a valid inference from the sample data to the population.4.2 This guide also provides a process to identify the sources of error (both systematic and random) so that an effort can be made to control or minimize these errors. These sources include sampling error, measurement error, and statistical bias.4.3 When the objective is limited to the taking of a representative (physical) sample or a representative set of (physical) samples, only potential sampling errors need to be considered. When the objective is to make an inference from the sample data to the population, additional measurement error and statistical bias need to be considered.4.4 This guide does not apply to the cases where the taking of a nonrepresentative sample(s) is prescribed by the study objective. In that case, sampling approaches such as judgment sampling or biased sampling can be taken. These approaches are not within the scope of this guide.4.5 Following this guide does not guarantee that representative samples will be obtained. But failure to follow this guide will likely result in obtaining sample data that are either biased or imprecise, or both. Following this guide should increase the level of confidence in making the inference from the sample data to the population.4.6 This guide can be used in conjunction with the DQO process (see Practice D5792).4.7 This guide is intended for those who manage, design, and implement sampling and analytical plans for waste management and contaminated media.1.1 This guide covers the definition of representativeness in environmental sampling, identifies sources that can affect representativeness (especially bias), and describes the attributes that a representative sample or a representative set of samples should possess. For convenience, the term “representative sample” is used in this guide to denote both a representative sample and a representative set of samples, unless otherwise qualified in the text.1.2 This guide outlines a process by which a representative sample may be obtained from a population. The purpose of the representative sample is to provide information about a statistical parameter(s) (such as mean) of the population regarding some characteristic(s) (such as concentration) of its constituent(s) (such as lead). This process includes the following stages: (1) minimization of sampling bias and optimization of precision while taking the physical samples, (2) minimization of measurement bias and optimization of precision when analyzing the physical samples to obtain data, and (3) minimization of statistical bias when making inferences from the sample data to the population. While both bias and precision are covered in this guide, major emphasis is given to bias reduction.1.3 This guide describes the attributes of a representative sample and presents a general methodology for obtaining representative samples. It does not, however, provide specific or comprehensive sampling procedures. It is the user's responsibility to ensure that proper and adequate procedures are used.1.4 The assessment of the representativeness of a sample is not covered in this guide since it is not possible to ever know the true value of the population.1.5 Since the purpose of each sampling event is unique, this guide does not attempt to give a step-by-step account of how to develop a sampling design that results in the collection of representative samples.1.6 Appendix X1 contains two case studies which discuss the factors for obtaining representative samples.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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5.1 If required by the authority having jurisdiction, pressurized gaseous testing media leak testing is conducted after installation to discover and correct or repair leaks or faults in a newly constructed or modified PA12 pressure piping system before placing the system in service. Leakage or faults most commonly occur at connections, joints, and mechanical seals where sealing under pressure is required.5.2 Safety is of paramount importance when conducting pressurized gaseous testing media leak tests because testing results include no leaks, leaks, sudden violent rupture, or catastrophic failure.5.3 Systems that contain lower pressure rated or non-pressure rated components that cannot be isolated or removed from exposure to test pressure, or where temporary caps or closures are not practical, are not suitable for testing in accordance with this practice.5.4 Leakage Allowance—Leakage is not allowed for butt and electrofusion joints, and restrained gas-tight mechanical joints. See 7.6. Contact the joint, connection or component manufacturer for leakage correction information if leakage occurs at a joint, connection or component having a mechanical seal.5.5 Poisson-Effect Expansion and Contraction—When test pressure is applied to plastic piping systems that have fully restrained joints such as heat fusion, electrofusion, bolted flanges, etc., either reduction of overall pipe length or an increase in longitudinal stress results from diametrical expansion of the pipe. Disjoining (pull-out) of partially restrained or non-restrained connections or joints, such as some in-line mechanical connectors having insufficient resistance to pull-out stress or length reduction, is possible when partially restrained or unrestrained joints are in-line with the fully restrained test section. To prevent Poisson-effect disjoining of partially restrained or non-restrained joints take measures such as installing external joint restraints (diametrical clamps and tie-rods) on in-line partially restrained or non-restrained joints, installing in-line thrust anchors at the ends of fully restrained piping sections to prevent end movement of the fully restrained section, or isolating a fully restrained test section from piping with unrestrained or partially restrained joints.NOTE 3: A tensile stress applied to a material will cause elongation in the direction of the applied stress, and will cause a decrease in dimension at right angles to the direction of the applied stress. The ratio of decrease to elongation is the Poisson ratio. Under test pressure, piping materials will expand slightly in diameter and contract in length slightly according to the Poisson ratio of the material.1.1 This practice provides information on apparatus, safety, pre-test preparation, and procedures for conducting field tests of polyamide-12 (PA12) pressure piping systems after installation using gaseous testing media such as un-odorized inert non-toxic gas or air, and applying pressure to determine if leaks exist in the system (pneumatic leak testing). This practice applies only to testing to discover leakage. Testing for other purposes such as testing to establish operating pressure is beyond the scope of this practice.1.2 Leak testing with pressurized gaseous testing media shall be used only if one or both of the following conditions exists:1.2.1 The piping system is so designed that it cannot be filled with a liquid, or1.2.2 The piping system service cannot tolerate traces of liquid testing media.1.3 Where hydrostatic testing is specified in contract documents or by the authority having jurisdiction, testing using pressurized gaseous testing media (pneumatic) testing shall not be substituted without the express consent and authorization of the authority having jurisdiction.1.4 Some manufacturers prohibit or restrict testing of their products with pressurized gaseous testing media. Contact component manufacturers for information. Where the manufacturer of a test section component prohibits or restricts testing with pressurized gaseous testing media testing in accordance with this practice shall not be used without the express consent and authorization of the authority having jurisdiction and the component manufacturer.NOTE 1: Components that are not suitable for testing with gaseous testing media may not be suitable for service with pressurized gas.1.5 This practice does not address leak testing using pressurized liquids (hydrostatic testing). For field leak testing using pressurized liquids, consult the manufacturer for guidance.1.6 This practice does not apply to leak testing of non-pressure, negative pressure (vacuum), or non-PA12 (polyamide-12) piping systems.1.7 This practice does not apply to fuel gas piping systems that extend from the point of delivery to the appliance connections. For other than undiluted liquefied petroleum gas (LP-Gas) systems, the point of delivery shall be considered to be the outlet of the service meter assembly or the outlet of the service regulator or service shutoff valve where no meter is provided. For undiluted LP-Gas, the point of delivery shall be considered to be the outlet of the final pressure regulator, exclusive of line gas regulators, in the system. This practice does not apply to LP-Gas systems covered under NFPA 58.1.8 This practice is intended for use with PA12 pressure piping that conveys gaseous media under pressure (compressed gas) if the owner or operator or installer of the line does not have an established leak testing procedure that is acceptable to the authority having jurisdiction.1.9 Warning—Failure during a pressurized gaseous testing media leak test can be extremely violent and dangerous because energy that is applied to compress the gaseous testing media and to pressurize the system will both be suddenly released.NOTE 2: To illustrate the violent hazard of failure, assume a 5 HP compressor is used to raise the test section to test pressure and that it takes 1 h to achieve test pressure. If sudden rupture occurs, energy release may occur in 2 s. Therefore, the horsepower of the energy release would be 5 HP × 1 h × 3600 s/h / 2 s = 9000 HP. Further, if diameter is doubled, energy release is four times greater. For an example test section that is twice the diameter, energy release would be 36 000 HP.1.10 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. Numbered notes and information in parentheses in the text of the practice are non-mandatory information. Table notes are mandatory information.1.11 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.1.12 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 determines the comparative performance of filter media. The results can be used for design, manufacturing, construction and selection of filter media.5.2 Results obtained by this test method should not be used to predict absolute performance on full scale fabric filter (baghouse) facilities, however these results will be useful in selection of proper filter media and identification of recommended operating parameters for these full scale fabric filter facilities.5.3 Dust types vary greatly; therefore, the results obtained using the standard dust should not be extrapolated to other dust types.1.1 This test method characterizes the operational performance of cleanable filter media under specified laboratory conditions.1.2 This test method determines the airflow resistance, drag, cleaning requirements, and particulate filtration performance of pulse cleaned filter media.1.3 This test method determines the comparative performance of cleanable filter media.1.4 The results obtained from this test method are useful in the design, construction, and selection of filter media.1.5 The results obtained by this test method should not be used to predict absolute performance of full scale fabric filter (baghouse) facilities, however these results will be useful in selection of proper filter media and identification of recommended operating parameters for these full scale fabric filter facilities.1.6 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered 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 guide discusses options for taking a subsample from a sample submitted to a laboratory. If followed, it will minimize the bias and variance of the characteristic of interest of the laboratory sample prior to analysis.4.2 The guide will describe appropriate instructions to be submitted to the laboratory with the field sample.4.3 This guide is intended for use in the laboratory to take a representative subsample or specimen of the whole field sample for direct analysis or sample preparation for analysis. It is intended for field personnel, data users, laboratory sample reception personnel, analysts, and managers.4.4 To obtain a representative subsample, layer analysis, grinding, mixing, and changing the physical state such as digesting, drying, melting, or freezing may be required. This guide considers cone and quartering, riffle splitting, and particle size reduction.1.1 This guide covers common techniques for obtaining representative subsamples from a sample received at a laboratory for analysis. These samples may include solids, sludges, liquids, or multilayered liquids (with or without solids).1.2 The procedures and techniques discussed in this guide depend upon the sample matrix, the type of sample preparation and analysis performed, the characteristic(s) of interest, and the project-specific instructions or data quality objectives.1.3 This guide includes several sample homogenization techniques, including mixing and grinding, as well as information on how to obtain a specimen or split laboratory samples.1.4 This guide does not apply to air or gas sampling.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 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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Information technology - Coding of audio-visual objects - Part 4: Conformance testing AMENDMENT 2: MPEG-4 conformance extensions for XMT and media nodes

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