5.1 The primary purpose of the PMA test is to determine the presence of mechanical damage, wear through, and other gross defects in the coating. Most metallic coatings are intended to be protective, and the presence of gross defects indicates a serious reduction of such protection.5.2 The protection afforded by well applied coatings may be diminished by improper handling following plating or as a result of wear or mechanical damage during testing or while in service. The PMA test can serve to indicate the existence of such damage.5.3 This test is used to detect underplate and substrate metal exposed through normal wear during relative motions (mating of electrical contacts) or through mechanical damage. As such, it is a sensitive pass/fail test and, if properly performed, will rapidly detect wear through to base metals or scratches that enter the base metal layers.5.4 This test is relatively insensitive to small pores. It is not designed to be a general porosity test and shall not be used as such. The detection of pores will depend upon their sizes and the length of time that the reagent remains a liquid.5.5 This test cannot distinguish degrees of wear through or whether the wear through is to nickel or copper. Once base metal is exposed, the colored molybdenum complex is formed. While relatively small area defects (compared to the area of the droplet) may be seen at the bottom of the drop as tiny colored regions immediately after applying the PMA, any larger areas of exposed base metal will cause the entire droplet to turn dark instantly.5.6 The PMA test also detects mechanical damage that exposes underplate and substrate metal. Such damage may occur in any postplating operation or even at the end of the plating operation. It can often occur in assembly operations where plated parts are assembled into larger units by mechanical equipment.5.7 The PMA test identifies the locations of exposed base metal. The extent and location of these exposed areas may or may not be detrimental to performance. The PMA test is not recommended for predictions of product performance, nor is it intended to simulate field failure mechanisms. For such contact performance evaluations, an environmental test known to simulate actual failure mechanisms should be used.5.8 The PMA test is primarily intended for the evaluation of individual samples rather than large sample lots, since evaluations are normally carried out one at a time under the microscope (see Section 10).5.9 This test is destructive. Any parts exposed to the PMA test shall not be placed in service.1.1 This test standard covers equipment and methods for using phosphomolybdic acid (PMA) to detect gross defects and mechanical damage including wear through in metallic coatings of gold, silver, or palladium. These metals comprise the topmost metallic layers over substrates of nickel, copper, or copper alloys.1.2 Recent reviews of porosity testing, which include those for gross defects, and testing methods can be found in the literature.2, 3 An ASTM guide to the selection of porosity and gross defect tests for electrodeposits and related metallic coatings is available as Guide B765. Other related porosity and gross defects test standards are Test Methods B735, B741, B798, B799, B809, and B866, Specifications B488, B679,and B689.1.3 The values stated in SI units are the preferred units. Those in parentheses are for information only.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The purpose of the alkaline polysulfide immersion test is to determine the presence of mechanical damage, wear-through, and other gross defects in the coating. Most metallic coatings are intended to be protective and the presence of gross defects indicates a serious reduction of such protection.5.2 The protection afforded by well applied coatings may be diminished by improper handling following plating or as a result of wear or mechanical damage during testing or while in service. The alkaline polysulfide test serves to indicate if the damage has extended down to the copper or copper alloy basis metal since it will not detect exposed nickel underplate.5.3 The alkaline polysulfide test has been specified in several ASTM specifications for tin-plated coatings, namely Specifications B246 and B545. This test could also be used to detect gross defects and mechanical damage in other metallic coatings, such as tin-nickel alloy (Specification B605), nickel (Specification B689), gold (Specification B488), palladium (Specification B679), and autocatalytic nickel-phosphorous coatings (Specification B733).5.4 This test detects mechanical damage that exposes copper underplate and copper basis metal. Such damage may occur in any post-plating operation or even towards the end of the plating operation. It is most often seen to occur in product assembly operations.5.5 If properly performed, this test will also detect wear-through, provided the wear-through reaches a copper or copper-alloy layer.5.6 Many types of gross defects are too small to be seen, except at magnifications so high (as in SEM) that a realistic assessment of the measurement area cannot be easily made. Other defects, such as many types of wear-through, provide insufficient contrast with the coating surface. Gross defects tests (as with porosity tests) are, therefore, used to magnify the defect sites by producing visible reaction products in and around the defects.5.7 The polysulfide solution will react with copper and copper alloys to produce a dark brown or black stain (the defect indications) at the site of the defect. Silver also turns black under the same conditions. The test solution will not react with nickel and is only useful when the presence or absence of copper exposure is a specific requirement.5.8 The polysulfide immersion test is relatively insensitive to the presence of small pores. It shall not be used as a general porosity test. (Test Method B809 should be used instead.)5.9 The extent and location of the gross defects or mechanical damage (revealed by this test) may or may not be detrimental to product performance or service life. Such determinations shall be made by the user of the test through practical experience or judgment.5.10 The present test can be used on samples of various geometries, such as curved surfaces. It can also be used for selective area coating if allowance is made for tarnish creepage from bare copper alloy areas.5.11 This test is destructive in that it reveals the presence of gross defects by contaminating the surface with reaction-product films. Any parts exposed to this test shall not be placed in service.5.12 However, the defect indications on the sample surfaces that result from this test are stable; samples may be retained for reference purposes.5.13 This test is neither recommended for predictions of product performance nor is it intended to simulate field failure mechanisms. For such product performance evaluations, an environmental test that is known to simulate actual failure mechanisms should be used.1.1 This test method covers equipment and methods for detecting gross defects and mechanical damage (including wear-through) in metallic coatings where the breaks in the coating penetrate down to a copper or copper alloy substrate.1.2 This test method is suitable for coatings consisting of single or combined layers of any coating that does not significantly tarnish in an alkaline polysulfide solution. Examples are gold, nickel, tin, tin-lead, and palladium, or their alloys.1.3 Recent reviews of porosity testing (which include those for gross defects) and testing methods can be found in literature.2,3 An ASTM guide to the selection of porosity and gross defect tests for electrodeposits and related metallic coatings is available as Guide B765. Other related porosity test standards are Test Methods B735, B741, B798, B799, and B809.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to 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 Susceptibility to damage from concentrated out-of-plane forces is one of the major design concerns of many structures made of advanced composite laminates. Knowledge of the damage resistance properties of a laminated composite plate is useful for product development and material selection.5.2 QSI testing can serve the following purposes:5.2.1 To simulate the force-displacement relationships of impacts governed by boundary conditions (1-7).5 These are typically relatively large-mass low-velocity hard-body impacts on plates with a relatively small unsupported region. Since the test is run slowly in displacement control, the desired damage state can be obtained in a controlled manner. Associating specific damage events with a force during a drop-weight impact test is often difficult due to the oscillations in the force history. In addition, a specific sequence of damage events may be identified during quasi-static loading while the final damage state is only identifiable after a drop-weight impact test.5.2.2 To provide an estimate of the impact energy required to obtain a similar damage state for drop-weight impact testing if all others parameters are held constant.5.2.3 To establish quantitatively the effects of stacking sequence, fiber surface treatment, variations in fiber volume fraction, and processing and environmental variables on the damage resistance of a particular composite laminate to a concentrated indentation force.5.2.4 To compare quantitatively the relative values of the damage resistance parameters for composite materials with different constituents. The damage response parameters can include dent depth, damage dimensions and through-thickness locations, Fmax , Ea, and Emax, as well as the force versus indenter displacement curve.5.2.5 To impart damage in a specimen for subsequent damage tolerance tests, such as Test Method D7137/D7137M.5.2.6 To measure the indentation response of the specimen with and without bending using the two specimen configurations (edge supported and rigidly backed).5.3 The properties obtained using this test method can provide guidance in regard to the anticipated damage resistance capability of composite structures of similar material, thickness, stacking sequence, etc. However, it must be understood that the damage resistance of a composite structure is highly dependent upon several factors including geometry, thickness, stiffness, mass, support conditions, etc. Significant differences in the relationships between force/energy and the resultant damage state can result due to differences in these parameters. For example, properties obtained using the specimen supported over a circular hole would more likely reflect the damage resistance characteristics of an un-stiffened monolithic skin or web than that of a skin attached to sub-structure which resists out-of-plane deformation. Similarly, test specimen properties would be expected to be similar to those of a panel with equivalent length and width dimensions, in comparison to those of a panel significantly larger than the test specimen, which tends to divert a greater proportion of the energy into elastic deformation.5.4 The standard indenter geometry has a blunt, hemispherical tip. Historically, for the standard laminate configuration, this indenter geometry has generated a larger amount of internal damage for a given amount of external damage than is typically observed for similar indenters using sharp tips. Alternative indenter geometries may be appropriate depending upon the damage resistance characteristics being examined. For example, the use of sharp tip geometries may be appropriate for certain damage visibility and penetration resistance assessments.5.5 Some testing organizations may desire to use this test method in conjunction with Test Method D7137/D7137M to assess the compression residual strength of specimens containing a specific damage state, such as a defined dent depth, damage geometry, etc. In this case, the testing organization should subject several specimens to multiple energy or force levels using this test method. A relationship between energy or force and the desired damage parameter can then be developed. Subsequent QSI and compression residual strength tests can then be performed using specimens indented at an interpolated energy or force level that is expected to produce the desired damage state.1.1 This test method determines the damage resistance of multidirectional polymer matrix composite laminated plates subjected to a concentrated indentation force (Fig. 1). Procedures are specified for determining the damage resistance for a test specimen supported over a circular opening and for a rigidly-backed test specimen. The composite material forms are limited to continuous-fiber reinforced polymer matrix composites, with the range of acceptable test laminates and thicknesses defined in 8.2. This test method may prove useful for other types and classes of composite materials.FIG. 1 Quasi-Static Indentation Test1.1.1 Instructions for modifying these procedures to determine damage resistance properties of sandwich constructions are provided in Practice D7766/D7766M.1.2 A flat, square composite plate is subjected to an out-of-plane, concentrated force by slowly pressing a hemispherical indenter into the surface. The damage resistance is quantified in terms of a critical contact force to cause a specific size and type of damage in the specimen.1.3 The test method may be used to screen materials for damage resistance, or to inflict damage into a specimen for subsequent damage tolerance testing. The indented plate can be subsequently tested in accordance with Test Method D7137/D7137M to measure residual strength properties. Drop-weight impact per Test Method D7136/D7136M may be used as an alternate method of creating damage from an out-of-plane force and measuring damage resistance properties.1.4 The damage resistance properties generated by this test method are highly dependent upon several factors, which include specimen geometry, layup, indenter geometry, force, and boundary conditions. Thus, results are generally not scalable to other configurations, and are particular to the combination of geometric and physical conditions tested.1.5 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 are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.5.1 Within the text the inch-pound units are shown in brackets.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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5.1 Squeeze-off is widely used to temporarily control the flow of gas in PE pipe. Squeeze tools vary depending on the size of the pipe and the design of the tool. Squeeze-off procedures vary depending on the tool design, pipe material, and environmental conditions.5.2 Experience indicates that some combinations of polyethylene material, temperature, tool design, wall compression percentage and procedure can cause damage leading to failure.5.3 Studies of polyethylene pipe extruded in the late 1980s and thereafter show that damage typically does not develop when the wall compression percentage is 30 % or less, when temperatures are above 50 °F (10 °C), and when closure and release rates are typical of field conditions for screw-driven tools.4 With tools meeting Specification F1563, acceptable flow control at typical gas service pressures is achieved at wall compression percentages between 10 and 20 % for pipe diameters less than 6 in.4,5 Because damage does not develop in these materials at such squeeze levels, the references cited indicate that squeeze-off flow control practices using tools meeting Specification F1563 and qualified procedures meeting Practice F1041 are effective for smaller pipe sizes.4 ,5NOTE 3: Specification F1563 provides a procedure for evaluating tool flow control performance.5.4 This practice provides a method to qualify a combination of squeeze tool, pipe size and material, and squeeze-off procedure to ensure that long-term damage does not occur. This practice is useful for polyethylene gas pipe manufactured before 1975, for new or revised polyolefin gas pipe materials, for pipe diameters of 8 in. or above, for new or revised squeeze tool designs, and for new or revised squeeze-off procedures.1.1 This practice covers qualifying a combination of a squeeze tool, a polyethylene gas pipe, and a squeeze-off procedure to avoid long-term damage in polyethylene gas pipe. Qualifying is conducted by examining the inside and outside surfaces of pipe specimens at and near the squeeze to determine the existence of features indicative of long-term damage. If indicative features are absent, sustained pressure testing in accordance with Specification D2513 is conducted to confirm the viability of the squeeze-off process. For assistance with specimen examination, an Adjunct, ADJF17342, is available from ASTM.1.2 This practice is appropriate for any combination of squeeze tool, PE gas pipe and squeeze-off procedure, and is particularly appropriate for pre-1975 Polyethylene (PE) pipe, and for pipe sizes of 8 in. or above, because of a greater possibility of long-term damage.1.3 This practice is for use by squeeze-tool manufacturers, pipe manufacturers and gas utilities to qualify squeeze tools made in accordance with Specification F1563; and squeeze-off procedures in accordance with Guide F1041 with pipe manufactured in accordance with Specification D2513.1.4 Governing codes and project specifications should be consulted. Nothing in this practice should be construed as recommending practices or systems at variance with governing codes and project specifications.1.5 Where applicable in this guide, “pipe” shall mean “pipe and tubing.”1.6 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.7 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 The ability to maintain design function (for example, reinforcement, separation, barrier, etc.) or design properties (for example, tensile strength, chemical resistance, etc.), or both, of a geosynthetic may be affected by damage to the physical structure of the geosynthetic due to the rigors of field installation. The effect of damage may be assessed by analyzing specimens cut from sample(s) retrieved after installation in a representative test section. Analysis may be performed with visual examination or laboratory testing of specimens from the control sample(s), and from the exhumed sample(s).5.2 A uniform practice for installing and retrieving representative sample(s) from a test section is needed to assess installation damage using project-specific or generally accepted, representative materials and procedures. Damage of a specific grade and type of geosynthetic under specific installation procedures may be assessed with sample(s) exhumed from a full-scale test section.1.1 This practice covers standardized procedures for obtaining samples of geosynthetics from a test section for use in assessment of the effects of damage immediately after installation caused only by the installation techniques. The assessment may include physical testing. This practice is applicable to any geosynthetic except those installed between layers of aggregate or soil modified by a binder.NOTE 1: The binder would inhibit the retrieval of the geosynthetic without inflicting further damage to the geosynthetic. Other practices may be suitable for retrieving geosynthetics used in these applications but are out of the scope of this practice.1.2 This practice is limited to full-scale test sections and does not address laboratory modeling of field conditions. This practice does not address which test method(s) to use for quantifying installation damage.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 Susceptibility to damage from concentrated out-of-plane impact forces is one of the major design concerns of many structures made of advanced composite laminates. Knowledge of the damage resistance properties of a laminated composite plate is useful for product development and material selection.5.2 Drop-weight impact testing can serve the following purposes:5.2.1 To establish quantitatively the effects of stacking sequence, fiber surface treatment, variations in fiber volume fraction, and processing and environmental variables on the damage resistance of a particular composite laminate to a concentrated drop-weight impact force or energy.5.2.2 To compare quantitatively the relative values of the damage resistance parameters for composite materials with different constituents. The damage response parameters can include dent depth, damage dimensions, and through-thickness locations, F1, Fmax, E1, and Emax, as well as the force versus time curve.5.2.3 To impart damage in a specimen for subsequent damage tolerance tests, such as Test Method D7137/D7137M.5.3 The properties obtained using this test method can provide guidance in regard to the anticipated damage resistance capability of composite structures of similar material, thickness, stacking sequence, and so forth. However, it must be understood that the damage resistance of a composite structure is highly dependent upon several factors, including geometry, thickness, stiffness, mass, support conditions, and so forth. Significant differences in the relationships between impact force/energy and the resultant damage state can result due to differences in these parameters. For example, properties obtained using this test method would more likely reflect the damage resistance characteristics of an unstiffened monolithic skin or web than that of a skin attached to substructure which resists out-of-plane deformation. Similarly, test specimen properties would be expected to be similar to those of a panel with equivalent length and width dimensions, in comparison to those of a panel significantly larger than the test specimen, which tends to divert a greater proportion of the impact energy into elastic deformation.5.4 The standard impactor geometry has a blunt, hemispherical striker tip. Historically, for the standard laminate configuration and impact energy, this impactor geometry has generated a larger amount of internal damage for a given amount of external damage, when compared with that observed for similar impacts using sharp striker tips. Alternative impactors may be appropriate depending upon the damage resistance characteristics being examined. For example, the use of sharp striker tip geometries may be appropriate for certain damage visibility and penetration resistance assessments.5.5 The standard test utilizes a constant impact energy normalized by specimen thickness, as defined in 11.7.1. Some testing organizations may desire to use this test method in conjunction with D7137/D7137M to assess the compressive residual strength of specimens containing a specific damage state, such as a defined dent depth, damage geometry, and so forth. In this case, the testing organization should subject several specimens, or a large panel, to multiple low velocity impacts at various impact energy levels using this test method. A relationship between impact energy and the desired damage parameter can then be developed. Subsequent drop weight impact and compressive residual strength tests can then be performed using specimens impacted at an interpolated energy level that is expected to produce the desired damage state.1.1 This test method determines the damage resistance of multidirectional polymer matrix composite laminated plates subjected to a drop-weight impact event. The composite material forms are limited to continuous-fiber reinforced polymer matrix composites, with the range of acceptable test laminates and thicknesses defined in 8.2.1.1.1 Instructions for modifying these procedures to determine damage resistance properties of sandwich constructions are provided in Practice D7766/D7766M.1.2 A flat, rectangular composite plate is subjected to an out-of-plane, concentrated impact using a drop-weight device with a hemispherical impactor. The potential energy of the drop-weight, as defined by the mass and drop height of the impactor, is specified prior to test. Equipment and procedures are provided for optional measurement of contact force and velocity during the impact event. The damage resistance is quantified in terms of the resulting size and type of damage in the specimen.1.3 The test method may be used to screen materials for damage resistance, or to inflict damage into a specimen for subsequent damage tolerance testing. When the impacted plate is tested in accordance with Test Method D7137/D7137M, the overall test sequence is commonly referred to as the Compression After Impact (CAI) method. Quasi-static indentation per Test Method D6264/D6264M may be used as an alternate method of creating damage from an out-of-plane force and measuring damage resistance properties.1.4 The damage resistance properties generated by this test method are highly dependent upon several factors, which include specimen geometry, layup, impactor geometry, impactor mass, impact force, impact energy, and boundary conditions. Thus, results are generally not scalable to other configurations, and are particular to the combination of geometric and physical conditions tested.1.5 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 are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.5.1 Within the text, the inch-pound units are shown in brackets.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 A characteristic advantage of charged-particle irradiation experiments is the precise, individual control over most of the important irradiation conditions such as dose, dose rate, temperature, and quantity of gases present. Additional attributes are the lack of induced radioactivation of specimens and, in general, a substantial compression of irradiation time, from years to hours, to achieve comparable damage as measured in displacements per atom (dpa). An important application of such experiments is the investigation of radiation effects that may occur in materials exposed to environments which do not currently exist, such as in first wall materials used in fusion reactors.4.2 The primary shortcoming of ion bombardments stems from the damage rate, or temperature dependences of the microstructural evolutionary processes in complex alloys, or both. It cannot be assumed that the time scale for damage evolution can be comparably compressed for all processes by increasing the displacement rate, even with a corresponding shift in irradiation temperature. In addition, the confinement of damage production to a thin layer just (often ∼1 μm) below the irradiated surface can present substantial complications. It must be emphasized, therefore, that these experiments and this practice are intended for research purposes and not for the certification or the qualification of materials.4.3 This practice relates to the generation of irradiation-induced changes in the microstructure of metals and alloys using charged particles. The investigation of mechanical behavior using charged particles is covered in Practice E821.1.1 This practice provides guidance on performing charged-particle irradiations of metals and alloys, although many of the methods may also be applied to ceramic materials. It is generally confined to studies of microstructural and microchemical changes induced by ions of low-penetrating power that come to rest in the specimen. Density changes can be measured directly and changes in other properties can be inferred. This information can be used to estimate similar changes that would result from neutron irradiation. More generally, this information is of value in deducing the fundamental mechanisms of radiation damage for a wide range of materials and irradiation conditions.1.2 Where it appears, the word “simulation” should be understood to imply an approximation of the relevant neutron irradiation environment for the purpose of elucidating damage mechanisms. The degree of conformity can range from poor to nearly exact. The intent is to produce a correspondence between one or more aspects of the neutron and charged-particle irradiations such that fundamental relationships are established between irradiation or material parameters and the material response.1.3 The practice appears as follows:  SectionApparatus 4Specimen Preparation 5 – 10Irradiation Techniques (including Helium Injection) 11 – 12Damage Calculations 13Postirradiation Examination 14 – 16Reporting of Results 17Correlation and Interpretation 18 – 221.4 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 Electronic circuits used in many space, military, and nuclear power systems may be exposed to various levels and time profiles of neutron radiation. It is essential for the design and fabrication of such circuits that test methods be available that can determine the vulnerability or hardness (measure of survivability) of components to be used in them. A determination of hardness is often necessary for the short term (≈100 μs) as well as long term (permanent damage) following exposure. See Practice E722.1.1 This guide defines the requirements and procedures for testing silicon discrete semiconductor devices and integrated circuits for rapid annealing effects from displacement damage resulting from neutron radiation. This test will produce degradation of the electrical properties of the irradiated devices and should be considered a destructive test. Rapid annealing of displacement damage is usually associated with bipolar technologies.1.1.1 Heavy ion beams can also be used to characterize displacement damage annealing (1),2 but ion beams have significant complications in the interpretation of the resulting device behavior due to the associated ionizing dose. The use of pulsed ion beams as a source of displacement damage is not within the scope of this standard.1.2 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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4.1 This practice was written primarily to guide test participants in establishing, identifying, maintaining, and using suitable environments for conducting high quality neutron tests. Its development was motivated, in large measure, because inadequate controls in the neutron-effects-test process have, in some past instances, resulted in exposures that have differed by factors of three or more from irradiation specifications. A radiation test environment generally differs from the environment in which the electronics must operate (the operational environment); therefore, a high quality test requires not only the use of a suitable radiation environment, but also control and compensation for contributions to damage that differ from those in the operational environment. In general, the responsibility for identifying suitable test environments to accomplish test objectives lies with the sponsor/user/tester and test specialist part of the team, with the assistance of an independent validator, if available. The responsibility for the establishment and maintenance of suitable environments lies with the facility operator/dosimetrist and test specialist, again with the possible assistance of an independent validator. Additional guidance on the selection of an irradiation facility is provided in Practice F1190.4.2 This practice identifies the tasks that must be accomplished to ensure a successful high quality test. It is the overall responsibility of the sponsor or user to ensure that all of the required tasks are complete and conditions are met. Other participants provide appropriate documentation to enable the sponsor or user to make that determination.4.3 The principal determinants of a properly conducted test are: (1) the radiation test environment shall be well characterized, controlled, and correlated with the specified irradiation levels; (2) damage produced in the electronic materials and devices is caused by the desired, specified component of the environment and can be reproduced at any other suitable facility; and (3) the damage corresponding to the specification level derived from radiation environments in which the electronics must operate can be predicted from the damage produced by the test environment. In order to ensure that these requirements are met, system developers, procurers, users, facility operators, and test personnel must collectively meet all of the essential requirements and effectively communicate to each other the tasks that must be accomplished and the conditions that must be met. Criteria for determining and maintaining the suitability of neutron radiation environments for 1-MeV equivalent displacement damage testing of electronics parts are presented in Section 5. Mandatory requirements for test consistency in neutron displacement damage testing of electronic parts are presented in Section 5. Additional background material on neutron testing and important considerations for gamma dose and dose rate effects are presented in (non-mandatory) Appendix X1 and Appendix X2, but compliance is not required.4.4 Some neutron tests are performed with a specific end application for the electronics in mind. Others are performed merely to ensure that a 1-MeV-equivalent-displacement-damage-specification level is met. The issues and controls presented in this practice are necessary and sufficient to ensure consistency in the latter case. They are necessary, but may not be sufficient, when the objective is to determine device performance in an operational environment. In either case, a corollary consistency requirement is that test results obtained at a suitable facility can be replicated within suitable precision at any other suitable facility.4.4.1 An objective of radiation effects testing of electronic devices is often to predict device performance in operational environments from the data that is obtained in the test environments. If the operational and test environments differ materially from each other, then damage equivalence methodologies are required in order to make the required correspondences. This process is shown schematically in Fig. 1. The part of the process (A, in Fig. 1) that establishes the operational neutron environments required to select the appropriate 1-MeV-equivalent specification level, or levels, is beyond the scope of this practice. However, if a neutron spectrum is used to set a 1 MeV equivalent fluence specification level, it is important that the process (B, in Fig. 1) be consistent with this practice. Damage equivalence methodologies must address all of the important contributors to damage in the operational and test environments or the objectives of the test may not be met. In the mixed neutron-gamma radiation fields produced by nuclear reactors, most of the permanent damage in solid-state semiconductor devices results from displacement damage produced by fast neutrons through primary knock-on atoms and their associated damage cascades. The same damage functions must be used by all test participants to ensure damage equivalence. Damage functions for silicon and gallium arsenide are provided in the current edition of Practice E722 (see Note 1). At present, no damage equivalence methodologies for neutron displacement damage have been developed and validated for semiconductors other than silicon and gallium arsenide.FIG. 1 Process for Damage EquivalenceNOTE 1: When comparing test specifications and test results from data obtained in historical tests, it may be necessary to adjust specifications and test data to account for changes in damage functions which have evolved through the years as more accurate and reliable damage functions have become available.4.4.2 If a 1-MeV equivalent neutron fluence specification, or a neutron spectrum, is provided, the damage equivalence methodology, shown schematically in Fig. 1, is used to ensure that the correct neutron fluence is provided and that the damage in devices placed in the exposure position correlates with the displacement energy from the neutrons at that location.1.1 This practice sets forth requirements to ensure consistency in neutron-induced displacement damage testing of silicon and gallium arsenide electronic piece parts. This requires controls on facility, dosimetry, tester, and communications processes that affect the accuracy and reproducibility of these tests. It provides background information on the technical basis for the requirements and additional recommendations on neutron testing.1.2 Methods are presented for ensuring and validating consistency in neutron displacement damage testing of electronic parts such as integrated circuits, transistors, and diodes. The issues identified and the controls set forth in this practice address the characterization and suitability of the radiation environments. They generally apply to reactor sources, accelerator-based neutron sources, such as 14-MeV DT sources, and 252Cf sources. Facility and environment characteristics that introduce complications or problems are identified, and recommendations are offered to recognize, minimize or eliminate these problems. This practice may be used by facility users, test personnel, facility operators, and independent process validators to determine the suitability of a specific environment within a facility and of the testing process as a whole. Electrical measurements are addressed in other standards, such as Guide F980. Additional information on conducting irradiations can be found in Practices E798 and F1190. This practice also may be of use to test sponsors (organizations that establish test specifications or otherwise have a vested interest in the performance of electronics in neutron environments).1.3 Methods for the evaluation and control of undesired contributions to damage are discussed in this practice. References to relevant ASTM standards and technical reports are provided. Processes and methods used to arrive at the appropriate test environments and specification levels for electronics systems are beyond the scope of this practice; however, the process for determining the 1-MeV equivalent displacement specifications from operational environment neutron spectra should employ the methods and parameters described herein. Some important considerations and recommendations are addressed in Appendix X1 (Nonmandatory information).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 The neutron test spectrum must be known in order to use a measured device response to predict the device performance in an operational environment (Practice E1854). Typically, neutron spectra are determined using a set of sensors with response functions sensitive over the neutron energy region to which the device under test (DUT) responds (Guide E721). For silicon bipolar devices exposed in reactor neutron spectra, this effective energy range is between 0.01 and 10 MeV. A typical set of activation reactions that lack fission reactions from nuclides such as  235U,  237Np, or  239Pu, will have very poor sensitivity to the spectrum between 0.01 and 2 MeV. For a pool-type reactor spectrum, 70 % of the DUT electronic damage response may lie in this range making its determination of critical importance.5.2 When dosimeters with a significant response in the 0.01 to 2 MeV energy region, such as fission foils, are unavailable, silicon transistors can provide a dosimeter with the needed response to define the spectrum in this critical energy range. When fission foils are part of the sensor set, the silicon sensor provides confirmation of the spectral shape in this energy region.5.3 Silicon bipolar transistors, such as type 2N2222A, are inexpensive, smaller than fission foils contained in a boron ball, and sensitive to a part of the neutron spectrum important to the damage of modern silicon electronics. They also can be used directly in arrays to spatially map 1-MeV(Si) equivalent displacement damage fluence. The proper set of steps to take in reading the transistor-gain degradation is described in this test method.5.4 The energy-dependence of the displacement damage function for silicon is found in Practice E722. The major portion of the response for the silicon transistors will generally be above 100 keV.1.1 This test method covers the use of 2N2222A silicon bipolar transistors as dosimetry sensors in the determination of neutron energy spectra and as 1-MeV(Si) equivalent displacement damage fluence monitors.1.2 The neutron displacement in silicon can serve as a neutron spectrum sensor in the range 0.1 to 2.0 MeV and can serve as a substitute when fission foils are not available. It has been applied in the fluence range between 2 × 1012 n/cm 2 to 1 × 1014 n/cm2 and should be useful up to 1 × 1015 n/cm2. This test method details the acquisition and use of 1-MeV(Si) equivalent fluence information for the partial determination of the neutron spectra by using 2N2222A transistors.1.3 This sensor yields a direct measurement of the silicon 1-MeV equivalent fluence by the transfer technique.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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4.1 Moisture degradation is frequently a significant factor that either limits the useful life of a building or necessitates costly repairs. Examples of moisture degradation include: (1) decay of wood-based materials, (2) spalling of masonry caused by freeze-thaw cycles, (3) damage to gypsum plasters by dissolution, (4) corrosion of metals, (5) damage due to expansion of materials or components (by swelling due to moisture pickup, or by expansion due to corrosion, hydration, or delayed ettringite formation), (6) spalling and degradation caused by salt migration, (7) failure of finishes, and (8) creep deformation and reduction in strength or stiffness.4.1.1 Moisture accumulation within construction components or constructions may adversely affect serviceability of a building, without necessarily causing immediate and serious degradation of the construction components. Examples of such serviceability issues are: (1) indoor air quality, (2) electrical safety, (3) degradation of thermal performance of insulations, and (4) decline in physical appearance. Mold or mildew growth can influence indoor air quality and physical appearance. With some components, in particular interior surface finishes, mold or mildew growth may limit service life of the component. Moisture conditions that affect serviceability issues can frequently be expected, unless corrected, to eventually result in degradation of the building or its components. This guide does not attempt however to address serviceability issues that could be corrected by cleaning and change in building operation, and that would not require repair or replacement of components to return the building (or portions or components of the building) to serviceability.4.2 Prevention of water-induced damage must be considered throughout the construction process including the various stages of the design process, construction, and building commissioning. It must also be considered in building operation and maintenance, and when the building is renovated, rehabilitated or undergoes a change in use.4.3 This guide is intended to alert designers and builders, and also building owners and managers, to potential damages that may be induced by water, regardless of its source. This guide discusses moisture sources and moisture migration. Limit states (or specific moisture conditions that are likely to impact construction or component durability) and design methods are also cursorily discussed. Examples of practices that enhance durability are listed and discussed, as are examples of constructions or circumstances to avoid. The examples listed are not all-inclusive. Lastly, field check lists are given. The checklists are not intended for use as is, but as guides for development of checklists which may vary with specific building designs and climates.1.1 This guide covers building design, construction, commissioning, operation, and maintenance.1.2 This guide addresses the need for systematic evaluation of factors that can result in moisture-induced damage to a building or its components. Although of great potential importance, serviceability issues which are often, but not necessarily, related to physical damage of the building or its components (for example, indoor air quality or electrical safety) are not directly addressed in this guide.1.3 The emphasis of this guide is on low-rise buildings. Portions of this guide; in particular Sections 5, 6, and 7; may also be applicable to high-rise buildings.1.4 This guide is not intended for direct use in codes and specifications. It does not attempt to prescribe acceptable limits of damage. Buildings intended for different uses may have different service life expectancies, and expected service lives of different components within a given building often differ. Furthermore, some building owners may be satisfied with substantially shorter service life expectancies of building components or of the entire building than other building owners. Lastly, the level of damage that renders a component unserviceable may vary with the type of component, the degree to which failure of the component is critical (for example, whether failure constitutes a life-safety hazard), and the judgement (that is, tolerance for damage) of the building owner. For the reasons stated in this paragraph, prescribing limits of damage would require listing many pages of exceptions and qualifiers and is beyond the scope of this guide.1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.6 This standard does not purport to address the safety concerns 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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5.1 Fretting wear and corrosion are potential serviceability factors in many machines. They have always been factors in shipping finished goods by truck or rail. Packing materials rubbing on a product in transit can make the product unsalable. Beverage cans and food cans can lose their trade dress and consumers often equate container damage to content damage.5.2 Clamping surfaces on injection molds are damaged by fretting motions on clamping. This damage is a significant cause for mold replacement.5.3 Machines in shipment are subject to fretting damage in the real area of contact of the bearings on the machines.5.4 Operating vibration and movement of mechanically clamped components, like screwed assemblies, can produce damage on the clamped faces and other faces that affects machine function or use. Many times fretting damage appears in the form of pits, which are stress concentrators that can lead to mechanical fractures.5.5 Electrical contacts in any device that is subject to vibration are susceptible to failure (open circuit) due to fretting damage at real areas of contact.5.6 This test method is intended to be used to identify mating couples that may be less prone to fretting damage than others. This information in turn is used to select materials of construction or surface treatments that are less prone to fretting damage for applications where fretting conditions are known or perceived to exist.5.7 When using this test method to screen candidate material pairs for a specific application, the user should ensure that the prescribed geometry and test conditions described in Sections 6 – 8 adequately simulate the intended end use. The rationale for any deviations from the prescribed test conditions, if any, shall be explained in the test report and, accordingly, the user shall report that they used a modified version of the standard.1.1 This test method may be used for either fundamental or applications-oriented studies of fretting damage. Accordingly, data from these tests may be used to rank the wear resistance of candidate material couples for certain types of machine components whose service life is limited by fretting.1.2 This test method uses a tribological bench test apparatus with a mechanism or device that will produce the necessary relative motion between a contacting hemispherical rider and a flat counterface. The rider is pressed against the flat counterface with a loading mass. The test method is intended for use in room temperature air. Other configurations or test parameters may be needed to investigate fretting in the presence of lubricants or other environments.1.3 The purpose of this test method is to rub two solid surfaces together under controlled fretting conditions and to quantify the damage to both surfaces in units of volume loss.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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4.1 This practice covers bearings and bearing components of all material compositions and grades. It may be used to develop a process for adequately handling bearings.4.2 Unless the proper conditions of an adequate facility, equipment, and trained personnel are available, it may be better not to inspect the bearings in-house. The danger of contaminating and damaging the bearings may be much greater than the possibility of receiving bearings that will not function.4.3 Bearings are easily damaged at the customers' receiving and test areas. In most cases, bearings should be accepted based on the bearing manufacturer’s certification. Certificates of quality (conformance) supplied by the bearing manufacturer may be furnished in lieu of actual performance of such testing by the receiving activity of the bearings. The certificate shall include the name of the purchaser, contract number/PO number, name of the manufacturer or supplier, item identification, name of the material, lot number, lot size, sample size, date of testing, test method, individual test results, and the specification requirements.4.4 This practice does not cover clean room requirements of miniature and instrument precision bearings. These bearings require clean room environments in accordance with ISO 14644-1 and ISO 14644-2.1.1 This practice covers requirements for the handling of all bearings and bearing components.1.2 This is a general practice. The individual bearing handling requirements shall be as specified herein or as specified in the contract or purchase order. In the event of any conflict between requirements of this practice and the individual bearing requirements of an OEM drawing, procurement specification, or other specification, the latter shall govern. Many companies, organizations, and bearing users have excellent facilities, equipment, and knowledgeable personnel for handling bearings. The thrust of this practice is for users that do not have this knowledge of bearings.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 A common result of cellular stress is an increase in DNA damage. DNA damage may be manifest in the form of base alterations, adduct formation, strand breaks, and cross linkages (19). Strand breaks may be introduced in many ways, directly by genotoxic compounds, through the induction of apoptosis or necrosis, secondarily through the interaction with oxygen radicals or other reactive intermediates, or as a consequence of excision repair enzymes (20-22). In addition to a linkage with cancer, studies have demonstrated that increases in cellular DNA damage precede or correspond with reduced growth, abnormal development, and reduced survival of adults, embryos, and larvae (16, 23, 24).5.1.1 The Comet assay can be easily utilized for collecting data on DNA strand breakage (9, 25, 26). It is a simple, rapid, and sensitive method that allows the comparison of DNA strand damage in different cell populations. As presented in this guide, the assay facilitates the detection of DNA single strand breaks and alkaline labile sites in individual cells, and can determine their abundance relative to control or reference cells (9, 16, 26). The assay offers a number of advantages; damage to the DNA in individual cells is measured, only extremely small numbers of cells need to be sampled to perform the assay (<10 000), the assay can be performed on practically any eukaryotic cell type, and it has been shown in comparative studies to be a very sensitive method for detecting DNA damage (2, 27) .5.1.2 These are general guidelines. There are numerous procedural variants of this assay. The variation used is dependent upon the type of cells being examined, the types of DNA damage of interest, and the imaging and analysis capabilities of the lab conducting the assay. To visualize the DNA, it is stained with a fluorescent dye, or for light microscope analysis the DNA can be silver stained (28). Only fluorescent staining methods will be described in this guide. The microscopic determination of DNA migration can be made either by eye using an ocular micrometer or with the use of image analysis software. Scoring by eye can be performed using a calibrated ocular micrometer or by categorizing cells into four to five classes based on the extent of migration (29, 30) . Image analysis systems are comprised of a CCD camera attached to a fluorescent microscope and software and hardware designed specifically to capture and analyze images of fluorescently stained nuclei. Using such a system, it is possible to measure the fluorescence intensity and distribution of DNA in and away from the nucleus (8). Using different procedural variants, the assay can be utilized to measure specific types of DNA alterations and DNA repair activity (1, 3, 8, 10, 13, 14, 17, 18). Alkaline lysis and electrophoresis conditions are used for the detection of single-stranded DNA damage, whereas neutral pH conditions facilitate the detection of double-strand breaks (31). Various sample treatments can be used to express specific types of DNA damage, or as in one method, to preserve strand damage at sites of DNA repair (10). Nuclease digestion steps can be used to introduce strand breaks at specific lesion sites. Using this approach, oxidative base damage can be detected by the use of endonuclease III (18), as well as DNA modifications resulting from exposure to ultraviolet light (UV) through the use of T4 endonuclease V (3). Modifications of this type vastly expand the utility of this assay and are good examples of its versatility.5.2 A sufficient knowledge of the biology of cells examined using this assay should be attained to understand factors affecting DNA strand breakage and the distribution of this damage within sampled cell populations. This includes, but is not limited to, influences such as cell type heterogeneity, cell cycle, cell turnover frequency, culture or growth conditions, and other factors that may influence levels of DNA strand damage. Different cell types may have vastly different background levels of DNA single-strand breaks due to variations in excision repair activity, metabolic activity, anti-oxidant concentrations, or other factors. It is recommended that cells representing those to be studied using the SCG/Comet assay be examined under the light or fluorescent microscope using stains capable of differentially staining different cell types. Morphological differences, staining characteristics, and frequencies of the different cell types should be noted and compared to SCG/Comet damage profiles to identify any possible cell type specific differences. In most cases, the use of homogenous cell populations reduces inter-cell variability of SCG/Comet values. The procedures for this assay, using cells from many different species and cell types, have been published previously (1, 2, 3, 5, 8, 10, 13, 14, 17, 18, 32-38). These references and others should be consulted to obtain details on the collection, handling, storage, and preparation of specific cell types.5.3 The experimental design should incorporate appropriate controls, reference samples, and replicates to delineate the influence of the major sources of experimental variability.1.1 This guide covers the recommended criteria for performing a single-cell gel electrophoresis assay (SCG) or Comet assay for the measurement of DNA single-strand breaks in eukaryotic cells. The Comet assay is a very sensitive method for detecting strand breaks in the DNA of individual cells. The majority of studies utilizing the Comet assay have focused on medical applications and have therefore examined DNA damage in mammalian cells in vitro and in vivo (1-4).2 There is increasing interest in applying this assay to DNA damage in freshwater and marine organisms to explore the environmental implications of DNA damage.1.1.1 The Comet assay has been used to screen the genotoxicity of a variety of compounds on cells in vitro and in vivo (5-7), as well as to evaluate the dose-dependent anti-oxidant (protective) properties of various compounds (3, 8-11). Using this method, significantly elevated levels of DNA damage have been reported in cells collected from organisms at polluted sites compared to reference sites (12-15). Studies have also found that increases in cellular DNA damage correspond with higher order effects such as decreased growth, survival, and development, and correlate with significant increases in contaminant body burdens (13, 16).1.2 This guide presents protocols that facilitate the expression of DNA alkaline labile single-strand breaks and the determination of their abundance relative to control or reference cells. The guide is a general one meant to familiarize lab personnel with the basic requirements and considerations necessary to perform the Comet assay. It does not contain procedures for available variants of this assay, which allow the determination of non-alkaline labile single-strand breaks or double-stranded DNA strand breaks (8), distinction between different cell types (13), identification of cells undergoing apoptosis (programmed cell death, (1, 17)), measurement of cellular DNA repair rates (10), detection of the presence of photoactive DNA damaging compounds (14), or detection of specific DNA lesions (3, 18) .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 guide is arranged as follows:  Section  1Referenced Documents 2Terminology 3Summary of Guide 4 5Equipment and Reagents 6Assay Procedures 7Treatment of Data 8Reporting Data 9Keywords 10Annex Annex A1References  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 The damage-based design approach will permit an additional method of design for GFRP materials. This is a very useful technique to determine the performance of different types of resins and composition of GFRP materials in order to develop a damage tolerant and reliable design. This AE-based method is not unique, other damage-sensitive evaluation methods can also be used.5.2 This practice involves the use of acoustic emission instrumentation and examination techniques as a means of damage detection to support a destructive test, in order to derive the damage-based design stress.5.3 This practice is not intended as a definitive predictor of long-term performance of GFRP materials (such as those used in vessels). For this reason, codes and standards require cyclic proof testing of prototypes (for example, vessels) which are not a part of this practice.5.4 Other design methods exist and are permitted.1.1 This practice details procedures for establishing the direct stress and shear stress damage-based design values for use in the damage-based design criterion for materials to be used in GFRP vessels and other GFRP structures. The practice uses data derived from acoustic emission examination of four-point beam bending tests and in-plane shear tests (see ASME Section X, Article RT-8).1.2 The onset of lamina damage is indicated by the presence of significant acoustic emission during the reload portion of load/reload cycles. “Significant emission” is defined with historic index.1.3 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units which 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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