1.1 本测试方法包括使用图像质量指示器（IQI）系统来确定相对 2. 直接热中子射线照相检查产生的射线照相图像的质量。本试验方法中提出的要求并非旨在控制材料和部件的质量水平。 1.2 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.3 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。 1.4 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====== 5.1 BPI旨在产生有关中子束和图像系统参数的定量信息，这些参数有助于胶片曝光，从而影响整体图像质量。此外，BPI可用于验证中子射线照相质量的日常一致性。钆转换屏和单乳剂卤化银膜一起暴露在中子成像束中，用于BPI的开发和测试。使用替代检测系统可能会产生对第节中使用的方程无效的密度读数 9 . 5.2 唯一真正有效的灵敏度指示器是参考标准件。参考标准零件是指与中子射线照相的物体相同的材料或部件，除非具有已知的标准不连续性、夹杂物、遗漏或缺陷。灵敏度指标旨在替代参考标准，并提供孔和间隙灵敏度的定性信息。 5.3 应在合同、采购订单、规范或图纸中规定要进行射线照相的区域或物体的数量以及使用的胶片验收标准。

1.1 This test method covers the use of an Image Quality Indicator (IQI) system to determine the relative 2 quality of radiographic images produced by direct, thermal neutron radiographic examination. The requirements expressed in this test method are not intended to control the quality level of materials and components. 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. ====== Significance And Use ====== 5.1 The BPI is designed to yield quantitative information concerning neutron beam and image system parameters that contribute to film exposure and thereby affect overall image quality. In addition, the BPI can be used to verify the day-to-day consistency of the neutron radiographic quality. Gadolinium conversion screens and single-emulsion silver-halide films, exposed together in the neutron imaging beam, were used in the development and testing of the BPI. Use of alternative detection systems may produce densitometric readings that are not valid for the equations used in Section 9 . 5.2 The only truly valid sensitivity indicator is a reference standard part. A reference standard part is a material or component that is the same as the object being neutron radiographed except with a known standard discontinuity, inclusion, omission, or flaw. The sensitivity indicators were designed to substitute for the reference standard and provide qualitative information on hole and gap sensitivity. 5.3 The number of areas or objects to be radiographed and the film acceptance standard used should be specified in the contract, purchase order, specification, or drawings.