放射性测量.γ射线发射放射性核素.用γ射线光谱法的通用试验方法

[中文适用范围]： 本文件描述了通过伽马射线光谱法测定测试样品中伽马射线发射放射性核素的贝克勒尔 (Bq) 活度的方法。 测量是在测试实验室中进行适当的样品制备后进行的。 测试样品可以是固体、液体或气体。 应用包括： ——对核设施或天然放射性物质排放量增加的场所释放的放射性进行常规监测； ——有助于确定环境中放射性的演变； ——调查事故和事故征候情况，以计划补救措施并监测其有效性； ——评估核退役活动中可能受到污染的废料； ——监测土壤、食品、饮用水、地下水、海水或污水污泥等介质中的放射性污染； ——用于估计体内伽马射线发射放射性核素的摄入量（吸入、摄入或注射）的测量。 假设本文件的用户已获得有关测试样本或场地的成分的信息。 在某些情况下，如果需要特征限值，则还指定了用于分析的放射性核素。 还假设测试样品已经均质化并代表了测试中的材料。 包括准备测量样品的一般指南。 然而，某些类型的样品需要按照本文件中提到的特定标准的要求来制备。 一般建议对于伽马射线发射器的原位测量也很有用。 本文件包括关于设备选择（见附件 A）、探测器（附件 D 中包含更详细的信息）以及仪器调试和方法验证的一般建议。 附录 F 总结了不同测量参数对典型伽马射线能谱测量系统结果的影响。 还涵盖质量控制和日常维护，但不包括探测器和脉冲处理电子设备的电气测试。 假设所使用的任何数据收集和分析软件均已根据相关软件标准（例如 ISO/IEC/IEEE 12207）编写和测试。 涵盖使用参考源和/或数值方法的校准，包括结果验证。 它还涵盖了从光谱中估计样品活性含量 (Bq) 的程序。 本文件中阐述的原则适用于测试实验室和现场的伽马射线能谱测量。 然而，给出了原位测量的详细要求。 本文件涵盖但不限于发射能量范围为5 keV至3000 keV的光子的伽马射线发射器。 然而，大多数测量值都落在 40 keV 至 2000 keV 范围内。 放射性活度 (Bq) 范围从环境样本中发现的低水平（亚 Bq）到事故条件和高水平放射性废物中发现的活动。  [外文原描述]： This document describes the methods for determining the activity in becquerel (Bq) of gamma‑ray emitting radionuclides in test samples by gamma-ray spectrometry. The measurements are carried out in a testing laboratory following proper sample preparation. The test samples can be solid, liquid or gaseous. Applications include: — routine surveillance of radioactivity released from nuclear installations or from sites discharging enhanced levels of naturally occurring radioactive materials; — contributing to determining the evolution of radioactivity in the environment; — investigating accident and incident situations, in order to plan remedial actions and monitor their effectiveness; — assessment of potentially contaminated waste materials from nuclear decommissioning activities; — surveillance of radioactive contamination in media such as soils, foodstuffs, potable water, groundwaters, seawater or sewage sludge; — measurements for estimating the intake (inhalation, ingestion or injection) of activity of gamma-ray emitting radionuclides in the body. It is assumed that the user of this document has been given information on the composition of the test sample or the site. In some cases, the radionuclides for analysis have also been specified if characteristic limits are needed. It is also assumed that the test sample has been homogenised and is representative of the material under test. General guidance is included for preparing the samples for measurement. However, some types of sample are to be prepared following the requirements of specific standards referred to in this document. The generic recommendations can also be useful for the measurement of gamma-ray emitters in situ. This document includes generic advice on equipment selection (see Annex A), detectors (more detailed information is included in Annex D), and commissioning of instrumentation and method validation. Annex F summarises the influence of different measurement parameters on results for a typical gamma-ray spectrometry system. Quality control and routine maintenance are also covered, but electrical testing of the detector and pulse processing electronics is excluded. It is assumed that any data collection and analysis software used has been written and tested in accordance with relevant software standards such as ISO/IEC/IEEE 12207. Calibration using reference sources and/or numerical methods is covered, including verification of the results. It also covers the procedure to estimate the activity content of the sample (Bq) from the spectrum. The principles set out in this document are applicable to measurements by gamma-ray spectrometry in testing laboratories and in situ. However, the detailed requirements for in situ measurement are given in ISO 18589-7 and are outside the scope of this document. This document covers, but is not restricted to, gamma-ray emitters which emit photons in the energy range of 5 keV to 3 000 keV. However, most of the measurements fall into the range 40 keV to 2 000 keV. The activity (Bq) ranges from the low levels (sub-Bq) found in environmental samples to activities found in accident conditions and high level radioactive wastes.