1.1 本试验方法涵盖了使用商用便携式太阳反射率计测定定向反射材料的太阳反射率的技术，包括但不限于具有颗粒或表面设计的屋顶材料，其可产生角度相关的反射率。该方法的目的是评估定向反射屋顶产品的季节和年度太阳反射率。 1.2 以国际单位表示的数值视为标准值。本标准不包括其他计量单位。 1.3 本标准并不旨在解决与其使用相关的所有安全问题（如有）。 本标准的使用者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 DRM的太阳反射率取决于太阳入射角。 该方法旨在为DRM屋顶产品提供太阳反射率值。

1.1 This test method covers a technique for determining the solar reflectance of a directionally reflective material using a commercial portable solar reflectometer, including but not limited to roofing materials with granules or surface design that results in angularly dependent reflectance. The purpose of the method is to evaluate the seasonal and annual solar reflectances of a directionally reflective roofing product. 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 solar reflectance of a DRM depends on the solar incidence angle. This method is intended to provide solar reflectance values for DRM roofing products.