1.1 本标准涵盖了使用近红外光谱法测定多元醇羟基数的实践。 1.2 描述了定义、术语和校准技术。概述了选择样品、收集和处理数据以进行近红外校准的程序。还描述了建立、评估和验证近红外校准模型的标准。最后，描述了样本处理、数据收集和评估的过程。 1.3 本标准的实施要求NIR光谱仪的安装符合制造商的规范。 1.4 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。 1.5 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。 注1: 本标准等同于ISO 15063。 1.6 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 通用工具: 5.1.1 为了形成聚氨酯体系，有必要了解多元醇的羟基数。 5.1.2 本规程适用于研究、质量控制、规范测试和过程控制。 5.2 限制: 5.2.1 在开始校准程序之前，需要确定影响分析物多元醇近红外光谱的因素。需要了解化学结构、干扰、任何非线性、温度的影响以及分析物与其他样品成分（如催化剂、水和其他多元醇）的相互作用，以便正确选择将模拟无法充分控制的影响的样品。 5.2.2 通常认为校准仅对用于生成校准的特定近红外仪器有效。使用不同的仪器（即使由同一制造商制造）进行校准和分析会严重影响测量羟基值的准确性和精密度。用于在仪器之间传输校准的程序存在问题，应按照第节中的指南小心使用 16 . 这些程序通常需要对新仪器上的误差进行全新的验证和统计分析。 5.2.3 分析结果仅在校准中使用的羟基值范围内统计有效。外推到较低或较高的羟基值可能会增加误差并降低精度。 同样，分析结果仅对用于校准集的相同化学成分有效。成分或污染物的显著变化也会影响结果。如实践中所讨论的，异常值检测 E1655 ，是一种可用于检测上述问题可能性的工具。

1.1 This standard covers a practice for the determination of hydroxyl numbers of polyols using NIR spectroscopy. 1.2 Definitions, terms, and calibration techniques are described. Procedures for selecting samples, and collecting and treating data for developing NIR calibrations are outlined. Criteria for building, evaluating, and validating the NIR calibration model are also described. Finally, the procedure for sample handling, data gathering and evaluation are described. 1.3 The implementation of this standard requires that the NIR spectrometer has been installed in compliance with the manufacturer's specifications. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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. Note 1: This standard is equivalent ISO 15063. 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. ====== Significance And Use ====== 5.1 General Utility: 5.1.1 It is necessary to know the hydroxyl number of polyols in order to formulate polyurethane systems. 5.1.2 This practice is suitable for research, quality control, specification testing, and process control. 5.2 Limitations: 5.2.1 Factors affecting the NIR spectra of the analyte polyols need to be determined before a calibration procedure is started. Chemical structure, interferences, any nonlinearities, the effect of temperature, and the interaction of the analyte with other sample components such as catalyst, water and other polyols needs to be understood in order to properly select samples that will model those effects which cannot be adequately controlled. 5.2.2 Calibrations are generally considered valid only for the specific NIR instrument used to generate the calibration. Using different instruments (even when made by the same manufacturer) for calibration and analysis can seriously affect the accuracy and precision of the measured hydroxyl number. Procedures used for transferring calibrations between instruments are problematic and are to be utilized with caution following the guidelines in Section 16 . These procedures generally require a completely new validation and statistical analysis of errors on the new instrument. 5.2.3 The analytical results are statistically valid only for the range of hydroxyl numbers used in the calibration. Extrapolation to lower or higher hydroxyl values can increase the errors and degrade precision. Likewise, the analytical results are only valid for the same chemical composition as used for the calibration set. A significant change in composition or contaminants can also affect the results. Outlier detection, as discussed in Practices E1655 , is a tool that can be used to detect the possibility of problems such as those mentioned above.