1.1 本规程提供了通过反射光进行外观测量的样本选择指南，并讨论了在准备测量时应考虑的因素。标准化的选择和呈现程序将有助于在不同实验室进行的评估之间达成一致，并有助于在视觉评估和仪器测量之间实现更好的相关性。 注1: 本标准不是涂料试板的制备规程； 参见实践 D823 . 1.2 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。 1.3 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 许多定期提交测量的样本在一定程度上偏离了理想要求。因此，仪器读数受到样本选择和呈现测量方式的重要影响。通过标准化和控制试验条件，促进了可重复测量。

1.1 This practice provides a guide to selection of specimens for appearance measurement by reflected light as well as a discussion of factors to be considered in their preparation for measurement. Standardized selection and presentation procedures will assist in achieving agreement between evaluations carried out in different laboratories as well as helping to achieve better correlations between visual evaluations and instrumental measurements. Note 1: This standard is not a practice for preparation of test panels of coatings; see Practices D823 . 1.2 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. 1.3 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 Many of the specimens that are regularly submitted to measurement depart in some degree from the ideal requirements. For this reason instrumental readings are affected importantly by the manner in which specimens are selected and presented for measurement. Reproducible measurements are facilitated by standardization and control of test conditions.