1.1 本指南概述了使用无损检测（NDA）仪器进行放射性材料测量的质量测量实践。本指南的主要目的是帮助用户获得高质量的NDA结果，即满足最终用户需求的结果。这是通过为数据的收集、分析、比较和应用提供可接受的统一基础来实现的。这些建议是在大多数领域实现高质量NDA测量的指南。 1.2 本指南适用于通过观察自发或受激核辐射或原子辐射（包括光子、中子或热量）来测量核材料的NDA仪器的使用。 推荐的校准、操作和保证方法代表了基于当前NDA技术的指导原则。全行业核材料测量应用和仪器的多样性妨碍了对具体测量情况的讨论。因此，遵守本指南中建议的实践必须基于对特定测量应用的贡献变量和性能要求的透彻理解。 1.3 对于给定的测量应用，必须由合格的NDA专业人员根据指南中提供的指导选择最佳仪器，并提供使用该仪器的建议 C1490 . 本指南用作参考，并补充确保仪器和方法正确实施所需的批判性思维、专业技能、专家判断和实验测试与验证。 1.4 本指南的目标受众包括但不限于管理层、审计师支持、NDA合格仪器操作员、NDA技术专家和NDA专业人员。 1.5 以国际单位制或英寸-磅单位表示的数值应单独视为标准值。每个系统中规定的值不一定是精确的等价物； 因此，为确保符合本标准，每个系统应独立使用，且两个系统的值不得组合。 1.6 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 4.1 本指南描述了旨在实现质量结果的NDA测量实践。本指南中提供的材料的应用应根据具体情况确定。并非所有应用都需要所有元素。 4.2 当测量项目或测量计划的目标有利于或需要NDA而非破坏性分析时，通常进行无损检测测量。当收集物品的代表性样品很困难或不可行（例如，废料和废物物品）、人员暴露会很严重、采样污染会扩散、二次废物的产生必须最小化、物品的重量和/或皮重无法轻易确定（例如，就地工艺设备）时，NDA通常受到青睐，快速转弯- 需要四分之一的测量结果，或者NDA测量的成本明显低于等效破坏性分析。 4.3 本指南中提供的原则应用于确定哪种测量类型最适合测量应用。该确定包括考虑待测量项目的特征以及测量计划的目标。 4.4 本指南适用于NDA仪器和测量方法套件，其中许多在参考文献中有详细描述 ( 1. ) 和 ( 2. ) . 7. 测量方法和适用使用参考的部分列表见 5.5.1 . 用户有义务在ASTM方法特定标准中寻求其他指导，因为本指南不优先。有关特定方法的更多信息，请参阅技术会议交易、期刊、商业应用说明和NRC/DOE出版物。 4.5 本指南可适用于从产品到废物的核材料范围内的许多情况。典型应用包括:超铀废物、低水平废物和混合废物的测量和表征；低于某一监管阈值的放射性测定，估计为非放射性- 检测到的放射性核素；受保障核材料的测量；发货人-收货人确认；核材料库存的确认；支持核临界安全评估；测量工艺系统中特殊核材料的滞留率；支持去污和退役活动；以及在拆除前后对设施、手套箱、热电池和环境进行的现场分析。 4.6 当应用于废物测量时，本指南应与废物管理计划结合使用，该计划根据以下部分或全部标准将分析项目的内容分为材料类别: 废物的体积密度，放射性成分和基质的化学形式，（α， n )中子强度、氢（慢化剂）和吸收剂含量、裂变材料的几何形状、厚度和分布，以及分析项目容器的尺寸和组成。每个矩阵可能需要一组不同的校准标准，并且可能具有不同的质量校准极限。对分析质量的影响（即最大限度地提高精度和减少偏差）在很大程度上取决于对该废物管理计划的遵守程度。 4.7 本指南阐述了质量测量实践的要素，如:； 核测量仪器及其维护；常见危害；设施准备情况和支持NDA设备的要求；项目范围、要求和目标；仪器的组装和部署；校准和测试；增强物理测试的计算建模；测量验证；预防性维护；以及测量控制程序。

1.1 This guide is a compendium of Quality Measurement Practices for performing measurements of radioactive material using nondestructive assay (NDA) instruments. The primary purpose of the guide is to assist users in arriving at quality NDA results, that is, results that satisfy the end user’s needs. This is accomplished by providing an acceptable and uniform basis for the collection, analysis, comparison, and application of data. The recommendations are guidelines to achieving quality NDA measurements in most areas. 1.2 This guide applies to the use of NDA instrumentation for the measurement of nuclear materials by the observation of spontaneous or stimulated nuclear or atomic radiations, including photons, neutrons, or heat. Recommended calibration, operating, and assurance methods represent guiding principles based on current NDA technology. The diversity of industry-wide nuclear materials measurement applications and instrumentation precludes discussion of specific measurement situations. As a result, compliance with practices recommended in this guide must be based on a thorough understanding of contributing variables and performance requirements of the specific measurement application. 1.3 Selection of the best instrument for a given measurement application and advice on the use of this instrument must be provided by a qualified NDA professional following guidance provided in Guide C1490 . This guide is to be used as a reference, and to supplement the critical thinking, professional skill, expert judgment, and experimental test and verification needed to ensure that the instrumentation and methods have been properly implemented. 1.4 The intended audience for this guide includes but is not limited to Management, Auditor Support, NDA Qualified Instrument Operators, NDA Technical Specialists, and NDA Professionals. 1.5 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. 1.6 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. ====== Significance And Use ====== 4.1 NDA measurement practices aimed at achieving quality results are described in this guide. The application of the material provided in this guide should be determined on a case by case basis. Not all elements are required for all applications. 4.2 Nondestructive assay measurements are typically performed when the items measured or goals of the measurement program favor or require NDA over destructive analysis. NDA is typically favored when collecting a representative sample of the item is difficult or impractical (for example, scrap and waste items), personnel exposure would be significant, spread of contamination from sampling would occur, generation of secondary waste must be minimized, the weight and/or tare weight of the item cannot easily be determined (for example, in place process equipment), rapid turn-around of the measurement results is needed, or the NDA measurement is significantly less expensive than the equivalent destructive analysis. 4.3 The principles provided in this guide should be used to determine which type of measurement is best suited to the measurement application. This determination involves consideration of the characteristics of the items to be measured, as well as the goals of the measurement program. 4.4 This guide applies to the suite of NDA instruments and measurement methods, many of which are described in detail in Refs ( 1 ) and ( 2 ) . 7 A partial listing of measurement methods and applicable use references is provided in 5.5.1 . It is incumbent upon the user to seek additional guidance within ASTM method-specific standards, as this guide does not take precedence. Additional information on specific methods is best found in technical meeting transactions, journals, commercial application notes, and NRC/DOE publications. 4.5 This guide may be applied to many situations spanning the range of nuclear materials from product through waste. Typical applications include: the measurement and characterization of transuranic wastes, low-level wastes, and mixed wastes; the determination of radioactivity below some regulatory threshold, estimated for non-detected radionuclides; the measurement of safeguarded nuclear materials; shipper receiver confirmation; confirmation of nuclear material inventory; support of nuclear criticality safety evaluations; measurement of holdup of special nuclear material in process systems; support of decontamination and decommissioning activities; and in-situ analyses of facilities, glove-boxes, hot cells, and the environment prior to and following demolition. 4.6 When applied to measurement of waste, this guide should be used in conjunction with a waste management plan that segregates the contents of assay items into material categories according to some or all of the following criteria: bulk density of the waste, chemical forms of the radioactive constituents and matrix, (α, n ) neutron intensity, hydrogen (moderator) and absorber content, geometry, thickness, and distribution of fissile material, and the assay item container size and composition. Each matrix may require a different set of calibration standards and may have different mass calibration limits. The effect on the quality of the assay (that is, maximizing precision and minimizing bias) can significantly depend on the degree of adherence to this waste management plan. 4.7 This guide addresses elements of quality measurement practice such as; nuclear measurement instrumentation and its care; common hazards; facility readiness and requirements to support the NDA equipment; project scoping, requirements and objectives; assembly and deployment of the instrument; calibration and test; computational modeling to augment physical testing; measurement validation; preventive maintenance; and the measurement control program.