4.1 Overview: 4.1.1 Assurance of product quality is derived from careful attention to many factors but is not limited to raw material acceptance, software workflow definition, product and process design and control, printing and post processing, equipment and systems installation, maintenance, and in-process and end-product testing.4.1.2 By managing these factors, a manufacturer can establish confidence that all finished manufactured units from successive lots will be acceptable and meet lot release criteria.4.1.3 The basic principles of quality assurance (QA) have as their goal the production of articles that are fit for their intended use. These principles may be stated as:4.1.3.1 Quality, safety, and effectiveness shall be designed and built into the product as well as the production process.4.1.3.2 AM product characteristics all cannot currently be verified after the process without destructive testing and therefore requires validation. Suitable consideration should be designed into the product and controls should be applied to the process during process validation.4.1.3.3 Critical steps of the production process impacting quality shall be controlled to maximize the probability that the finished product meets all quality and design specifications.4.1.4 Process validation is a key element in ensuring that these QA goals are met. Routine end-product testing alone is often not sufficient to assure product quality. Some end-product tests have limited sensitivity. In some cases, destructive testing would be required to show that the manufacturing process is adequate, and in other situations, end-product testing does not reveal all variations that may occur in the product that may have an impact on device performance. However, successfully validating a process may reduce the dependence on intensive in-process and finished product testing. Note that, in most cases, end-product testing plays a major role in supporting QA goals, that is, validation and end-product testing are not mutually exclusive.4.1.5 Key process variables should be monitored and documented using statistical process control where applicable. Analysis of the data collected from monitoring should establish the potential variability of process parameters for individual production runs to ensure that a process is within acceptable control limits and the equipment can consistently produce the product within specification.4.2 Preliminary Considerations: 4.2.1 A manufacturer should evaluate all factors that affect product quality through appropriate documented process characterization.4.2.2 Risk management and an analysis file shall be created in line with ISO 14971. These factors may vary considerably among different products, manufacturing technologies, and facilities. No single approach to process validation will be appropriate and complete in all cases; however, the following quality steps should be undertaken.4.2.3 All pertinent aspects of the production processes that have an impact on device design (product’s end use) should be considered during process validation. These aspects include, but are not necessarily limited to, performance, reliability, and stability. Performance limits and variation should be established for each characteristic acceptance criteria and expressed in readily measurable terms. Once a product specification is defined it is important that any changes to it be made in accordance with documented change control procedures and the device history file.1.1 This practice provides an overview of how to perform process validation for medical devices manufactured using PBF/LB/M. The topics that will be covered include machine qualifications, software used in the manufacturing process, the importance of design specification and verification on process validation, and raw materials.1.2 This practice also provides recommendations for process characterization, risk management, additive manufacturing (AM) facility qualification, and process control as a prerequisite for qualification activity, including installation qualification/operational qualification/performance qualification (IQ/OQ/PQ).1.3 The practice is primarily focused on non-device-specific AM system(s) validation. Additional information may be needed in reference to the performance of the actual device.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 This guide will help manufacturers and users of AM powder feedstocks to identify suitable methods for measuring moisture in the feedstocks.5.2 This guide will aid control of powder quality and allow powder producers and users of AM machines to assess moisture content of virgin and reused powders.5.3 This guide is intended to support acceptance and control tests.5.4 Moisture levels are usually relatively low in metallic powder feedstocks (typically lower than 250 µg/g) but could be significantly more important in polymer and ceramic (typically lower than 10 000 µg/g).5.5 Moisture may affect powder processability (powder supply and feeding, layer creation) and influence the process and properties of the printed components. As different processes and machines use powders with different characteristics (that is, particle size distribution and shape) and AM machines store and handle powders in different ways, the amount of moisture and its impact may vary significantly depending on the feedstock, process, and machine.5.6 A proportion of the water is physisorbed on the surface and can be easily adsorbed and desorbed.5.7 A fraction of the water can be strongly bonded to the surface of the powder (that is, chemisorbed) and can be difficult to extract even at temperatures significantly higher than 100 °C. Thus, the water may not all be recovered during the moisture analysis and some water may remain in the samples. Consequently, the values obtained during the tests may be underestimated. As water bonds differently to different materials, the evaporation of water as a function of temperature may vary from one material to another.5.8 Because of the reactive nature of powders, water may react with the surface of the powder and form oxides and hydroxides. Thus, the amount of moisture may change with time even if the powder is stored in a tightly sealed container. Reaction of the powder with water may also happen during the analysis as the powder is heated up. This reaction will reduce the amount of water available at the surface of the powder and may impact the results (that is, underestimate the amount of water measured). If such reactions are expected to occur, their impact on the measurements should be evaluated. This can be done using oxygen analysis to evaluate the amount of oxide formed with time or during a test.5.9 The amount of water adsorbed on the surface of a powder depends on temperature and relative humidity and is determined by moisture sorption isotherm (water content in equilibrium on a material surface at a given temperature and moisture content). Depending on the temperature and humidity content of the atmosphere, water can adsorb and desorb from the surface of the material to reach an equilibrium with its environment.5.10 In consideration of 5.6 – 5.9, the amount of moisture in powders may change progressively and be affected by the storage, handling, and conditions of utilization. Thus, moisture content should only be measured at the time of interest (for example, shipping, reception, and usage). If not, evaluating how moisture and oxygen content evolve with time is recommended. This can be done by exposing the powder to humidity and evaluating how the moisture and oxygen content (using inert gas fusion method such as described in Test Method E1409) change with time. The effect of handling can be evaluated by measuring the moisture in test samples before and after a selected operation (for example, sieving, splitting). The stability of the moisture content depends on the nature and specific surface area of the powder and shall be evaluated for every material to be tested.5.11 The optimum test temperature depends on the material and equipment used. Test conditions should be selected to recover the maximum amount of water while the AM feedstock is not modified or deteriorated. For most equipment and AM powders, the maximum temperature of the equipment is not high enough to recover all the water from the samples and the amount of water is usually underestimated.5.12 To determine the most suitable test temperature for a specific material, tests can be performed at different temperatures from 50 °C up to the maximum temperature of the equipment. The suitable temperature can be chosen to evaporate the maximum amount of water while avoiding a modification (for example, oxidation or degradation) of the samples during the test. For some materials, it may not be possible to recover all water before the onset of the modification of the material. Consequently, the selection of the test temperature shall be selected case by case.5.13 Results can only be compared if the tests are conducted under similar conditions (temperature, time, heating rate, gas flow rate, and end criteria) and test methods have been validated and compared with reference materials (see Section 8).5.14 Depending on the design of the equipment, evaporation conditions (effective temperature seen by the samples, gas flow, and water extraction from the surface of the powder) may differ from one model of equipment to another. Validation of measurements using reference materials should be done before comparing results obtained in different laboratories or with different equipment or procedures to make sure they are comparable.1.1 This standard provides guidelines for measuring moisture in powder feedstock used in additive manufacturing (AM). It applies to metallic, ceramic, and polymer AM powder feedstocks.1.2 This guide provides a description of test methods commonly used to measure moisture and references to their associated standards.1.3 This guide provides best practice guidance on how to apply the test methods to make them suitable for AM powder characterization.1.4 This guide is suitable for measuring moisture in AM powder feedstock over the range of 10 µg/g to 10 000 µg/g.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1.1 This specification covers additive manufacturing of parts via full-melt laser beam powder bed fusion (PBF-LB) processing of maraging steel alloys. Parts made using this processing method are typically used in applications that require mechanical properties similar to wrought products, either as fabricated or heat treated. Products built to this specification may require additional post-processing in the form of machining, polishing, etc., to meet necessary surface finish and dimensional requirements.1.2 Maraging steel (MS) is a class of precipitation hardened steel, where aging heat treatment is used to form precipitates and, consequently, achieve significantly increased hardness and strength. This specification focuses specifically on 300 grade maraging steel, which corresponds to UNS K93120 and EN1.2709. MS grade 300 has higher concentrations of cobalt and titanium than lower grades.1.3 This specification is intended for the use of purchasers or producers, or both, of additively manufactured maraging steel parts for defining the requirements and ensuring part properties.1.4 Users are advised to use this specification as a basis for obtaining parts that will meet the minimum acceptance requirements established and revised by consensus of committee members.1.5 User requirements considered more stringent may be met by the addition to the purchase order of one or more supplementary requirements, which include, but are not limited to, those listed in Supplementary Requirements in Sections S1 to S3.1.6 The values stated in SI units are to be regarded as standard. All units of measure included in this guide are accepted for use with the SI.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The overall objective of this practice is to provide recommendations for the systematic acquisition of image data that indicate the health condition of the wear-sensitive SPW in PBF-LB/M machines. These data may allow a user to determine calibration and maintenance cycles based on the actual health condition of the SPW.4.2 The recommendations are intended for original equipment manufacturers (OEMs) of PBF-LB/M machines to provide guidance for the implementation of sensor systems to acquire spatially resolved data about the health condition of the SPW.4.3 The recommendations are intended for users of PBF-LB/M machines to provide guidance for the assessment of the actual health condition of the SPW to:4.3.1 Flag when a calibration or maintenance of the optical system is needed and alert the user or OEM to perform the calibration or maintenance and4.3.2 Generate statistical estimates for the useful life, or critical health state, of the SPW based on data recorded over the long term. The statistics may be used to derive maintenance cycles that allow a better utilization of the useful life of the SPW than current predetermined maintenance cycles.1.1 This practice provides:1.1.1 Recommendations for the design and integration of an area scan camera system (referred to as “camera system”) into a laser powder bed fusion (PBF-LB/M) machine to assess the health condition of the scanner protective window (SPW),1.1.2 Recommendations for data acquisition with the aforementioned system,1.1.3 Description of a methodology for processing the aforementioned data, and1.1.4 Recommendation on ex-situ measurements of laser beam parameters and part properties suitable for labeling of the processed condition data.1.2 Many of the operational descriptions included in this practice are intended as general overviews. They may not present the detailed information required.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 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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3.1 The surface roughness of PM parts is an important characteristic in relation to factors such as their load-bearing, wear, sealing, sliding, adhesion, electrical contact, and lubricant retention properties.3.2 Surface roughness may also be critical for component assembly or system performance. Dimensional fit and mating surface interaction may require certain surface roughness requirements to meet performance specifications.1.1 These test methods cover measuring the surface roughness of powder metallurgy (PM) products at all stages of manufacturing from green compact to fully hardened finished component.1.2 These test methods provide the definition and schematic of some common surface roughness parameters (Ra, Rt, and RzISO)1.3 This standard specifies two different standardized procedures for measuring the surface roughness of PM parts.1.3.1 Method 1 uses a conical stylus and a Gaussian filter.1.3.2 Method 2 uses a chisel (knife) edge stylus.1.3.3 Each test method results in a different measure of surface roughness and the results are not directly comparable.1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.5 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 test method is useful for selecting coating powders that gel in the desired time at the specified temperature. The method is not useful for determination of cure time.1.1 This test method determines the length of time a thermosetting coating powder takes to gel on a polished metal surface at a specified temperature, such as 204°C (400°F). The determination of the gel time is a very simple method for the characterization and quality control of coating powders. However, the gel time determined by this method is not directly related to the time for the coating powder to cure in practical applications.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 and health practices and determine the applicability of regulatory limitations prior to use.1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 Determining optimal strategies for the measurement and characterization of surface texture is necessary to increase confidence in the assessment of surfaces and in any further comparisons and correlations sought between manufactured surfaces, manufacturing processes, and desired functionality. Further, measurement and characterization of surface texture have implications in the field of tribology and in the determination and specification of part quality. This guide is designed to provide users of measurement technologies in both industry and academia with good practice for optimizing measurements of surfaces produced by metal powder bed fusion (PBF) manufacturing processes. While the focus of this guide is on surfaces produced by metal PBF, some of the referenced methods may also be appropriate for surfaces produced by other manufacturing processes.1.1 This guide is designed to introduce the reader to techniques for surface texture measurement and characterization of surfaces made with metal powder bed fusion additive manufacturing processes. It refers the reader to existing standards that may be applicable for the measurement and characterization of surface texture.1.2 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This guide describes the use of torque and angle-of-twist data as a preliminary acceptance criteria for a production run utilizing a previously qualified AM process through periodical or continuous evaluation. A torsion device (for example, torque wrench, instrumented lathe with torque readout) is used to break strategically placed torque specimens within the build volume in the as-built state to provide evidence of build health. If a round of tests from a production run is determined to fall outside of some criteria (for example: 3 standard deviations from the mean or other user defined criteria), additional qualification procedures should be performed to ensure the AM machine or process health are acceptable.NOTE 1: It is advantageous to locate the specimen at the same build height and near-critical locations of the part or component being fabricated for the evaluation to be representative of the specific region.5.2 This guide is not intended to replace rigorous qualification procedures and should only be considered as a preliminary acceptance criterion to increase confidence that an AM machine or process has not been significantly compromised.1.1 This guide illustrates a test specimen geometry and testing protocol that can be used to assess the quality of a metal powder bed fusion build cycle as it could be affected by major system errors (for example, corrupted calibration, disrupted inert gas flow, laser wear) severely affecting the quality of materials fabricated by laser beam powder bed fusion (PBF-LB).1.2 This method is designed to interrupt the manufacturing process if poor material quality is identified through go/no-go torque/angle of twist measurements of witness coupons after each fabrication.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 guide.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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定价： 605元 / 折扣价： 515 元

This specification covers the magnetic property requirements of 50 nickel-50 iron soft magnetic parts fabricated by powder metallurgy techniques in the sintered or annealed conditions, intended for parts that require high magnetic permeability, high electrical resistivity, low coercive field strength, and low hysteresis loss. This specification does not cover parts produced by metal injection molding. Parts shall be tested and adhere to the chemical composition, sintered density and coercive field strength requirements listed in this specification. Appendices contain information on typical magnetic properties and heat treatment.1.1 This specification covers the magnetic properties of 50 nickel-50 iron parts fabricated by powder metallurgy techniques and is intended for parts that require high magnetic permeability, high electrical resistivity, low coercive field strength, and low hysteresis loss. It differs from the wrought alloy specification (see Specification A753) because these parts are porous. A number of magnetic properties such as permeability are proportional to the sintered density.1.2 This specification deals with powder metallurgy parts in the sintered or annealed condition. Should the sintered parts be subjected to any secondary operation that causes mechanical strain, such as machining or sizing, they should be resintered or annealed.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to customary (cgs-emu and inch-pound) units, which are provided for information only and are not considered standard.1.3.1 There are selected values presented in two units, both of which are in acceptable SI units. These are differentiated by the word “or,” as in “μΩ-cm, or, Ω-m.”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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1.1 This specification defines the physical and chemical requirements for hafnium oxide powder intended for fabrication into shapes for use in a nuclear reactor core.1.2 The material described herein shall be particulate in nature.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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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This specification tackles standards for pressure consolidated powder metallurgy iron-nickel-chromium-molybdenum and nickel-chromium-molybdenum-columbium pipe flanges, fittings, valves, and parts intended for general corrosion or heat-resisting service. Compacts shall be manufactured by placing a single powder blend into a can, evacuating the can, and sealing it. The can material shall then be selected to ensure that it has no deleterious effect on the final product. The specimen shall be heated and placed under sufficient pressure for a sufficient period of time to ensure that the final consolidated part is fully dense. The powder shall be produced by vacuum melting followed by gas atomization. The heats shall be thoroughly mixed to ensure homogeneity when powder from more than one heat is used to make a blend. The material shall have the chemical compositions of carbon, manganese, silicon, phosphorus, sulfur, chromium, molybdenum, nickel, iron, cobalt, columbium, aluminum, titanium, nitrogen, and copper. Hydrostatic test shall be conducted and the specimen must show no leaks. The density test shall be performed using sample suspended from a scale and weighed in air and water using Archimede’s principle. Check Analysis shall be wholly the responsibility of the purchaser. The parts of the specimen shall be uniform in quality and condition, and shall be free from injurious imperfections.1.1 This specification covers pressure consolidated powder metallurgy nickel alloy pipe flanges, fittings, valves, and parts intended for general corrosion or heat-resisting service.1.1.1 UNS N06625 products are furnished in two grades of different heat-treated conditions:1.1.1.1 Grade 1 (annealed)—Material is normally employed in service temperatures up to 1100 °F (593 °C).1.1.1.2 Grade 2 (solution annealed)—Material is normally employed in service temperatures above 1100 °F (593 °C) when resistance to creep and rupture is required.1.2 UNS N08367 products are furnished in the solution annealed condition.1.3 UNS N06600 products are furnished in the annealed condition.1.4 UNS N06690 products are furnished in the annealed condition.1.5 UNS N07718 products are furnished in the solution annealed + precipitation hardened condition.1.6 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 The following safety hazards caveat pertains only to test methods portions, Sections 7.3 and 13, of this specification: 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 become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and to 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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This practice is useful for the preparation of specimens of ore bodies for the analysis of uranium by X-ray emission. Two separate preparation techniques are described.1.1 This practice covers the preparation of uranium ore samples to be analyzed by X-ray emission. Two separate techniques, the glass fusion method or the pressed powder method, may be used.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 problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

定价： 0元 / 折扣价： 0 元

4.1 This test method is for estimating the relative amount of gamma alumina in calcined catalyst or catalyst carrier samples, assuming that the X-ray powder diffraction peak occurring at about 67 °2θ is attributable to gamma alumina. Gamma alumina is defined as a transition alumina formed after heating in the range from 500 to 550 °C, and may include forms described in the literature as eta, chi, and gamma aluminas. Delta alumina has a diffraction peak in the same region, but is formed above 850 °C, a temperature to which most catalysts of this type are not heated. There are other possible components which may cause some interference, such as alpha-quartz and zeolite Y, as well as aluminum-containing spinels formed at elevated temperatures. If the presence of interfering material is suspected, the diffraction pattern should be examined in greater detail. More significant interference may be caused by the presence of large amounts of heavy metals or rare earths, which exhibit strong X-ray absorption and scattering. Comparisons between similar materials, therefore, may be more appropriate than those between widely varying materials.1.1 This test method covers the determination of gamma alumina and related transition aluminas in catalysts and catalyst carriers containing silica and alumina by X-ray powder diffraction, using the diffracted intensity of the peak occurring at about 67 °2θ when copper Kα radiation is employed.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.

定价： 515元 / 折扣价： 438 元 加购物车