1.1 本指南涵盖了一种实时、现场测量传输非偏振光的多模阶跃折射率石英光纤的辐射诱导光谱衰减的方法。本程序特别针对稳态电离辐射（即α、β、γ、质子等），根据辐射源的不同，在剂量测定和屏蔽方面有适当的变化。 1.2 本测试程序的目的不是测试基于光纤的系统的光学和非光学组件的平衡，但可以修改为在连续辐照环境中测试其他组件。 1.3 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。 1.4 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。 1.5 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 电离环境将影响用于从远程位置传输光谱信息的光纤/电缆的性能。为了评估光纤传感器系统的性能，必须确定光纤中电离辐射产生的光谱衰减或干扰或两者的类型和幅值。 4.2 测试结果可作为光纤光谱传感器系统中使用的光纤的选择标准。 注1: 当暴露于电离辐射时，光纤的衰减通常会增加。这主要是由于在光学材料的缺陷位置捕获辐射电子和空穴，即形成色心。这些色心通过热和/或光学（光漂白）过程或两者的结合而减少，会导致恢复，通常会导致辐射引起的衰减减少。辐照后衰减的恢复取决于许多变量，包括测试样品的温度、样品的成分、使用的光谱和辐射类型、应用于测试样品的总剂量、用于测量衰减的光强和工作光谱。在某些连续条件下，恢复永远不会完成。

1.1 This guide covers a method for measuring the real time, in situ radiation-induced spectral attenuation of multimode, step index, silica optical fibers transmitting unpolarized light. This procedure specifically addresses steady-state ionizing radiation (that is, alpha, beta, gamma, protons, etc.) with appropriate changes in dosimetry, and shielding considerations, depending upon the irradiation source. 1.2 This test procedure is not intended to test the balance of the optical and non-optical components of an optical fiber-based system, but may be modified to test other components in a continuous irradiation environment. 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 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. ====== Significance And Use ====== 4.1 Ionizing environments will affect the performance of optical fibers/cables being used to transmit spectroscopic information from a remote location. Determination of the type and magnitude of the spectral attenuation or interferences, or both, produced by the ionizing radiation in the fiber is necessary for evaluating the performance of an optical fiber sensor system. 4.2 The results of the test can be utilized as a selection criteria for optical fibers used in optical fiber spectroscopic sensor systems. Note 1: The attenuation of optical fibers generally increases when exposed to ionizing radiation. This is due primarily to the trapping of radiolytic electrons and holes at defect sites in the optical materials, that is, the formation of color centers. The depopulation of these color centers by thermal and/or optical (photobleaching) processes, or both, causes recovery, usually resulting in a decrease in radiation-induced attenuation. Recovery of the attenuation after irradiation depends on many variables, including the temperature of the test sample, the composition of the sample, the spectrum and type of radiation employed, the total dose applied to the test sample, the light level used to measure the attenuation, and the operating spectrum. Under some continuous conditions, recovery is never complete.