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4.1 Transfer Standards—One purpose of this test method is for the direct calibration of displacement transducers for use as secondary standards for the calibration of AE sensors for use in nondestructive evaluation. For this purpose, the transfer standard should be high fidelity and very well behaved and understood. If this can be established, the stated accuracy should apply over the full frequency range up to 1 MHz.NOTE 1: The stated accuracy applies only if the transfer standard returns to quiescence, following the transient input, before any wave reflected from the boundary of the calibration block returns to the transfer standard (∼100 μs). For low frequencies with periods on the order of the time window, this condition is problematical to prove.4.2 Applications Sensors—This test method may also be used for the calibration of AE sensors for use in nondestructive evaluation. Some of these sensors are less well behaved than devices suitable for a transfer standard. The stated accuracy for such devices applies in the range of 100 kHz to 1 MHz and with less accuracy below 100 kHz.1.1 This test method covers the requirements for the absolute calibration of acoustic emission (AE) sensors. The calibration yields the frequency response of a transducer to waves, at a surface, of the type normally encountered in acoustic emission work. The transducer voltage response is determined at discrete frequency intervals of approximately 10 kHz up to 1 MHz. The input is a given well-established dynamic displacement normal to the mounting surface. The units of the calibration are output voltage per unit mechanical input (displacement, velocity, or acceleration).1.2 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 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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3.1 Because of the wide variety of materials being used in neutron-activation measurements, this guide is presented with the objective of bringing improved uniformity to the specific field of interest here: hardness testing of electronics primarily in critical assembly reactor environments.NOTE 2: Some of the techniques discussed are useful for 14-MeV dosimetry. See Test Method E496 for activation detector materials suitable for 14-MeV neutron effects testing.NOTE 3: The materials recommended in this guide are suitable for 252Cf or other weak source effects testing provided the fluence is sufficient to generate countable activities.3.2 This guide is organized into two overlapping subjects: the criteria used for sensor selection, and the procedures used to ensure the proper determination of activities for determination of neutron spectra. See Terminology E170 and Test Methods E181. Determination of neutron spectra with activation sensor data is discussed in Guides E721 and E944.1.1 This guide covers the selection and use of neutron-activation detector materials to be employed in neutron spectra adjustment techniques used for radiation-hardness testing of electronic semiconductor devices. Sensors are described that have been used at many radiation hardness-testing facilities, and comments are offered in table footnotes concerning the appropriateness of each reaction as judged by its cross-section accuracy, ease of use as a sensor, and by past successful application. This guide also discusses the fluence-uniformity, neutron self-shielding, and fluence-depression corrections that need to be considered in choosing the sensor thickness, the sensor covers, and the sensor locations. These considerations are relevant for the determination of neutron spectra from assemblies such as TRIGA- and Godiva-type reactors and from Californium irradiators. This guide may also be applicable to other broad energy distribution sources up to 20 MeV.NOTE 1: For definitions on terminology used in this guide, see Terminology E170.1.2 This guide also covers the measurement of the gamma-ray or beta-ray emission rates from the activation foils and other sensors as well as the calculation of the absolute specific activities of these foils. The principal measurement technique is high-resolution gamma-ray spectrometry. The activities are used in the determination of the energy-fluence spectrum of the neutron source. See Guide E721.1.3 Details of measurement and analysis are covered as follows:1.3.1 Corrections involved in measuring the sensor activities include those for finite sensor size and thickness in the calibration of the gamma-ray detector, for pulse-height analyzer deadtime and pulse-pileup losses, and for background radioactivity.1.3.2 The primary method for detector calibration that uses secondary standard gamma-ray emitting sources is considered in this guide and in Test Methods E181. In addition, an alternative method in which the sensors are activated in the known spectrum of a benchmark neutron field is discussed in Guide E1018.1.3.3 A data analysis method is presented which accounts for the following: detector efficiency; background subtraction; irradiation, waiting, and counting times; fission yields and gamma-ray branching ratios; and self-absorption of gamma rays and neutrons in the sensors.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.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 Spectral analysis of soils for agricultural use is being used worldwide to obtain rapid data on soil nutrients. for the purpose of agricultural management including fertilizer application and other amendments such as pH adjustment, organic supplements, etc. Satellite, aerial, and ground-based sampling methods are being used. This test method applies to ground-based, terrestrial field applications where samples are taken from the ground, generally in the root zone. Use of these rapid remote sensing techniques allow for more detailed and economic data acquisition than older cumbersome sampling and wet chemistry testing methods used in the past by soil scientists for soil nutrient evaluations.5.2 This test method describes procedures for sampling and testing of field soils using diffuse reflectance spectrometry using handheld portable spectrometers measuring spectra in visible and near infrared (vis-NR) using dried sieved or wet samples. There is a worldwide effort to collect spectral databases of soils. The procedures specified here follow procedures as outlined in the United Nations Food and Agricultural Organization (FAO) primer on Vis-NIR and MIR spectroscopy of soils (1)3. Other organizations such as IEEE are actively working on additional guidance documents that will be incorporated in future revisions of this test method.5.2.1 This standard describes the procedures (Section 12) for using hyperspectral sensor data to measure moisture content as a percentage, pH, Organic Matter (OM) as a percentage, Cation Exchange Capacity (CEC) measured in 10 cmol c /kg could hold 10 cmol of Na + cations (with 1 unit of charge per cation) per kilogram of soil, but only 5 cmol Ca 2+ (2 units of charge per cation), as well as micro and macro nutrients in soils measured in PPM (parts per million)or a percentage, including, but not limited to nitrogen, phosphorous, potassium, boron, zinc, iron, sulfur, calcium, magnesium, and manganese.5.2.2 Research has shown that the Vis-NIR data for OM content is as accurate as other tests such as the burn off test in Test Methods D2974 (2). Analysis of natural moisture samples using method B can provide faster testing and better estimates of OM are normalization for moisture (3). Wet sampling allows for many more samples to be rapidly scanned in the field and therefore more samples and more detailed coverage of the site.5.3 This standard does not address sensors that measure in the mid infrared range, MIR, are more expensive and there is less spectral data available. MIR spectral analysis is performed on dried samples that are finely grinded (4). MIR modeling requires a high level of calibration against recognized laboratory procedures and physical properties.5.4 Spectral data can differ from older reference tests typically based on wet chemistry methods such as pore fluid extractions such as those outlined in soil survey manuals (5). These old methods require extensive labor costs and long turnaround times. However, soil scientists are accumulating large databases of spectral libraries which have been checked and calibrated with baseline chemical data. The soil survey manual (5) also has early (2014) procedures for Vis-NIR testing methods on dry specimens.5.5 The accuracy of the measurement is determined by the accuracy of the calibration of the baseline measurements that are calibrated by chemical processing. On critical/new projects the sampling plan may include samples for wet chemistry testing to help calibrate the site model. The large amount of data that is collected at a site is combined into a site-specific database which is subject to complex model training to optimize the dataset. This standard will not provide detailed guidance on modeling and the FAO document (1) provides a good overview of the current procedures for dataset modeling. Dataset modeling requires adjustments for texture, water content, and geology and generally is linked to other appropriate spectral libraries available from many sources (6).5.5.1 Horizon and Soil taxonomic order as auxiliary variables improve prediction accuracy of models. Regional, local, and past site-specific data, and taxonomic historic data base libraries may be used to help calibrate a site model.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 test method describes procedures for sampling and testing of soils obtained from ground-based samples using diffuse reflectance spectrometry using handheld portable spectrometers measuring spectra in visible and near infrared (vis-NR) and mid-infrared (MIR) range. The sensor can measure moisture content, PH, organic matter, Cation Exchange Capacity (CEC) as well as macro and micro elemental nutrients in parts per million (PPM) or percentage, including but not limited to nitrogen, phosphorous, potassium, zinc, iron, boron, sulfur, calcium, magnesium, and manganese.1.2 There are two methods that can be used to perform the test.1.2.1 Method A—The analysis is performed in the laboratory on the sample after the sample has been oven dried and sieved.1.2.2 Method B—The analysis is performed in the field on a moist sample after homogenization. After post-processing of multiple reflectance site data using methods A and B, the moisture content can be measured, and the spectral signature is normalized for moisture content.1.3 The limitation of this method is that the results of an individual test for elemental analysis would not be the same as exacting reference values from traditional wet chemical lab analysis used by soil scientists. Results of wet chemistry tests or tests from soil science libraries may be used to calibrate a specific site model comprised of many individual tests. Spectral data for organics has shown to be as accurate as conventional methods such as Test Methods D2974.1.4 For soil nutrient analysis the sample is not finely ground as in typical qualitative spectral analysis as outlined in standard Practice E1252. The spectrometer is checked periodically during testing using procedures in accordance with Guide E1866 performance testing.1.5 Moisture content is a preferred term in agricultural applications. For this standard, gravimetric water content may be measured in accordance with Test Methods D2216 when drying samples and used to calibrate the site model, but the overall results of spectral analysis are more qualitative, and the term Moisture Content is used in this standard.1.6 Units—The values stated in either SI units or inch-pound units [given in brackets] are to be regarded separately as standard. Wavelengths are stated only in nanometers, nm. 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 nonconformance with the standard.1.7 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026. The procedures used to specify how data is 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 analysis methods for engineering design.1.7.1 Spectral data is acquired by electrical data acquisition systems and therefore numeric data is carried through recording and into databases without rounding of numeric data.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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4.1 It is important to know the energy spectrum of the particular neutron source employed in radiation-hardness testing of electronic devices in order to relate radiation effects with device performance degradation.4.2 This guide describes the factors which must be considered when the spectrum adjustment methodology is chosen and implemented. Although the selection of sensors (foils) and the determination of responses (activities) is discussed in Guide E720, the experiment should not be divorced from the analysis. In fact, it is advantageous for the analyst conducting the spectrum determination to be closely involved with the design of the experiment to ensure that the data obtained will provide the most accurate spectrum possible. These data include the following: (1) measured responses such as the activities of foils exposed in the environment and their uncertainties, (2) response functions such as reaction cross sections along with appropriate correlations and uncertainties, (3) the geometry and materials in the test environment, and (4) a trial function or prior spectrum and its uncertainties obtained from a transport calculation or from previous experience.1.1 This guide covers procedures for determining the energy-differential fluence spectra of neutrons used in radiation-hardness testing of electronic semiconductor devices. The types of neutron sources specifically covered by this guide are fission or degraded energy fission sources used in either a steady-state or pulse mode.1.2 This guide provides guidance and criteria that can be applied during the process of choosing the spectrum adjustment methodology that is best suited to the available data and relevant for the environment being investigated.1.3 This guide is to be used in conjunction with Guide E720 to characterize neutron spectra and is used in conjunction with Practice E722 to characterize damage-related parameters normally associated with radiation-hardness testing of electronic semiconductor devices.NOTE 1: Although Guide E720 only discusses activation foil sensors, any energy-dependent neutron-responding sensor for which a response function is known may be used (1).2NOTE 2: For terminology used in this guide, see Terminology E170.1.4 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.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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CSA Preface This is the second edition of CAN/CSA-C22.2 No. 61010-2-032, Safety requirements for electrical equipment for measurement, control, and laboratory use - Part 2-032: Particular requirements for hand-held and hand-manipulated current sensors

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4.1 Defects in film are not acceptable to the end-user as there is a reduction in the fitness-for-use in many applications. This document is intended to be a practice to assist users in the inspection, quantification and observation of defects.4.2 This practice is applicable in a laboratory environment, continuous inspection as a quality control or as a research tool. It is also appropriate for use in any commercial process used to produce film including extrusion, calendaring, etc.4.3 This practice is also suitable for use as an evaluation or screening tool for materials intended to be used in other processes where defects of this nature are critical, such as fiber spinning non-woven, etc.4.4 Results achieved by different equipment, even from the same vendor in the same laboratory, are often not directly comparable as a bias exists that cannot be fully addressed through consistent operating conditions. Results frequently shift when analyzer components are upgraded. Additionally, results are often not directly comparable between different product types. All results are to be considered as relative values rather than absolute.4.4.1 Therefore, it is not recommended to provide absolute results as part of a sales contract between the buyer and seller. For sales contracts, it is recommended to establish product grade designations based on the historical relationship of the absolute results reported, and fitness-for-use or based on a reference material agreed by both parties. This is attained by the collection of data over a time-period to establish acceptable control limits.4.4.2 The defect size range of interest is usually different between resin supplier and converters. Total defect counts are not one to one comparable between small laboratory extrusion lines and commercial extrusion lines. Therefore, an individual correlation is the aim to get accepted results for fitness-for-use.NOTE 2: This was tested on Brabender, Collin, Goettfert, and OCS systems.4.5 For support in a basic interpretation of the different results the following points may be helpful for comparison.4.5.1 Size classes (number and definition)4.5.2 Reported defect types4.5.3 Comparable units (gels/kg, gels/m2, class system, index...)4.5.4 Vendor (type of equipment, for example, cast or blown film...)4.5.5 Camera settings (sensitivity, grey level, resolution...)4.5.6 Extrusion parametersNOTE 3: For attribute data such as defect counts, C-type control charts are most appropriate per recommendations within Practice E2587, Section 9.1.1 This practice intends to provide standardized approaches and criteria for the observation and reporting of defects in various types of plastic film, by means of an optical scanning system. includes the in situ inspection of defects in films fabricated for specific applications after preparation of a suitable film from plastic resin.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.NOTE 1: There is no known ISO equivalent to this standard.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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5.1 Workability is one of the main factors that influence the compaction quality and ultimately the performance of asphalt pavement. This method uses the relative rotation measured by the wireless particle-size sensor to evaluate the workability of the asphalt mixture.5.2 This test method is used to generate information concerning the workability of an asphalt mixture. Workability characteristics, in turn, can give users insight as to how the mixture will handle and compact in the field.5.3 This method is used to evaluate workability of the mix in a situation where it is being used for research or mix design. It is not intended to be a quality control (QC) evaluation.5.4 This test method can be used to evaluate conventional and modified asphalt mixtures to achieve the best workability at an appropriate compaction temperature. The test method can be used to determine the compaction temperature and optimal dosage rate of additives or modifiers to achieve the best workability for the modified asphalt mixtures, such as polymer modified, crumb rubber modified, waste plastic modified, etc.5.5 This test method is appropriate for laboratory-produced mixtures and plant-produced mixtures, regardless of the type or grade of the binder, the type or gradation of the aggregates, and whether RAP, WMA additives, or other modifiers are used in the asphalt mixture.NOTE 1: The quality of the results produced by this standard is dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely ensure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.1.1 This test method covers the determination of relative rotation to evaluate the workability of asphalt mixture during compaction using a wireless particle-size sensor. It is applicable to asphalt mixture being compacted using the Superpave Gyratory Compactor (SGC).1.2 This test method is appropriate for use to determine the relative rotation of laboratory-produced and plant-produced asphalt mixtures, regardless of the type or gradation of the aggregates, and whether reclaimed asphalt pavement (RAP), warm mix asphalt (WMA) additives, or any type of modifiers are used in the asphalt mixture.1.3 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.4 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered requirements of the standard.1.5 Since a complete precision and bias statement for this standard has not been developed, the test method is to be used for research and informational purposes only. Therefore, this standard should not be used for acceptance or rejection of a material for purchasing purposes.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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4.1 Conformable Eddy Current Sensors—Conformable, eddy current sensors can be used on both flat and curved surfaces, including fillets, cylindrical surfaces, etc. When used with models for predicting the sensor response and appropriate algorithms, these sensors can measure variations in physical properties, such as electrical conductivity or magnetic permeability, or both, as well as thickness of conductive coatings on any substrate and nonconductive coatings on conductive substrates or on a conducting coating. These property variations can be used to detect and characterize heterogeneous regions within the conductive coatings, for example, regions of locally higher porosity.4.2 Sensors and Sensor Arrays—Depending on the application, either a single-sensing element sensor or a sensor array can be used for coating characterization. A sensor array provides a better capability to map spatial variations in coating thickness or conductivity, or both (reflecting, for example, porosity variations), and provides better throughput for scanning large areas. The size of the sensor footprint and the size and number of sensing elements within an array depend on the application requirements and constraints, and the nonconductive (for example, ceramic) coating thickness.4.3 Coating Thickness Range—The conductive coating thickness range over which a sensor performs best depends on the difference between the electrical conductivity of the substrate and conductive coating and available frequency range. For example, a specific sensor geometry with a specific frequency range for impedance measurements may provide acceptable performance for an MCrAlY coating over a nickel-alloy substrate for a relatively wide range of conductive coating thickness, for example, from 75 to 400 μm (0.003 to 0.016 in.). Yet, for another conductive coating-substrate combination, this range may be 10 to 100 μm (0.0004 to 0.004 in.). The coating characterization performance may also depend on the thickness of a nonconductive topcoat. For any coating system, performance verification on representative coated specimens is critical to establishing the range of optimum performance. For nonconductive coatings, such as ceramic coatings, the thickness measurement range increases with an increase of the spatial wavelength of the sensor (for example, thicker coatings can be measured with larger sensor winding spatial wavelength). For nonconductive coatings, when roughness of the coating may have a significant effect on the thickness measurement, independent measurements of the nonconductive coating roughness, for example, by profilometry, may provide a correction for the roughness effects.4.4 Process-Affected Zone—For some processes, for example, shot peening, the process-affected zone can be represented by an effective layer thickness and conductivity. These values can in turn be used to assess process quality. A strong correlation must be demonstrated between these “effective coating” properties and process quality.4.5 Three-Unknown Algorithm—Use of multiple-frequency impedance measurements and a three-unknown algorithm permits independent determination of three unknowns: (1) thickness of conductive nonmagnetic coatings, (2) conductivity of conductive nonmagnetic coatings, and (3) lift-off that provides a measure of the nonconductive coating thickness.4.6 Accuracy—Depending on the material properties and frequency range, there is an optimal measurement performance range for each coating system. The instrument, its air standardization or reference substrate standardization, or both, and its operation permit the coating thickness to be determined within ±15 % of its true thickness for coating thickness within the optimal range and within ±30 % outside the optimal range. Better performance may be required for some applications.4.7 Databases for Sensor Response—Databases of sensor responses may be used to represent the model response for the sensor. These databases may be based upon physical models or empirical relations. The databases list expected sensor responses (for example, the real and imaginary parts or the magnitude and phase of the complex transimpedance between the sense element and drive winding) over relevant ranges in the properties of interest. Example properties for a coated substrate material are the magnetic permeability or electrical conductivity of the substrate, or both, the electrical conductivity and thickness of the coating, and the lift-off. The ranges of the property values within the databases should span the expected property ranges for the material system to be examined.1.1 This practice covers the use of conformable eddy current sensors for nondestructive characterization of coatings without standardization on coated reference parts. It includes the following: (1) thickness measurement of a conductive coating on a conductive substrate, (2) detection and characterization of local regions of increased porosity of a conductive coating, and (3) measurement of thickness for nonconductive coatings on a conductive substrate or on a conductive coating. This practice includes only nonmagnetic coatings on either magnetic (μ ≠ μ0) or nonmagnetic (μ = μ0) substrates. In addition to discrete coatings on substrates, this practice can also be used to measure the effective thickness of a process-affected zone (for example, shot peened layer for aluminum alloys, alpha case for titanium alloys) and to assess the condition of other layered media such as joints (for example, lap joints and skin panels over structural supports). For specific types of coated parts, the user may need a more specific procedure tailored to a specific application.1.2 Specific uses of conventional eddy current sensors are covered by Practices D7091 and E376 and the following test methods issued by ASTM: B244 and E1004. Guidance for the use of conformable eddy current sensor arrays is provided in Guide E2884.1.3 Units—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.1.4 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 Leakage of gas or liquid from a pressurized system, whether through a crack, orifice, seal break, or other opening, may involve turbulent or cavitational flow, which generates acoustic energy in both the external atmosphere and the system pressure boundary. Acoustic energy transmitted through the pressure boundary can be detected at a distance by using a suitable acoustic emission sensor.4.2 With proper selection of frequency passband, sensitivity to leak signals can be maximized by eliminating background noise. At low frequencies, generally below 100 kHz, it is possible for a leak to excite mechanical resonances within the structure that may enhance the acoustic signals used to detect leakage.4.3 This practice is not intended to provide a quantitative measure of leak rates.1.1 This practice describes a passive method for detecting and locating the steady state source of gas and liquid leaking out of a pressurized system. The method employs surface-mounted acoustic emission sensors (for non-contact sensors see Test Method E1002), or sensors attached to the system via acoustic waveguides (for additional information, see Terminology E1316), and may be used for continuous in-service monitoring and hydrotest monitoring of piping and pressure vessel systems. High sensitivities may be achieved, although the values obtainable depend on sensor spacing, background noise level, system pressure, and type of leak.1.2 Units—The values stated in either SI units or inch-pound units are to be regarded 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 standards.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.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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