1.1这些试验方法确定并报告了粉末涂层在两个参数方面的遮盖力: 1.1.1试验方法A-给定薄膜厚度下的对比度 1.1.2试验方法B-对比度为0.98（98%）时的薄膜厚度。 注1-通过测量与膜厚度相关的遮盖力，而不是测试方法D 344和D 2805以及其他遮盖力测试方法中使用的更传统的“扩散率”函数，测量参数符合粉末涂料行业惯例。 注2:遮盖力在光度上定义为0.98对比度下的扩散率。请参阅术语D 16、D 2805以及油漆和涂层测试手册中的铺展率和遮盖力定义。 注3:0.98的对比度在涂料行业中通常被接受，表示反射隐藏功率测量的“完全”隐藏。但在视觉上，以及在光度上，它都略不完整。 1.2这些试验方法包括测定静电喷涂粉末涂层的遮盖力。 1.3这些试验方法通过反射计和测厚仪测量来确定遮盖力。它们仅限于最小CIE-Y反射率为15%的涂层。 1.4以国际单位制表示的数值应视为标准。括号中给出的值仅供参考。 1.5本标准无意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和健康实践，并确定监管限制的适用性。

1.1 These test methods determine and report the hiding power of a powder coating with respect to two parameters: 1.1.1 Test Method A-Contrast Ratio at a given film thickness 1.1.2 Test Method B-Film thickness at 0.98 (98%) contrast ratio. Note 1-The measured parameters conform to powder coating industry practice by measuring hiding power in relation to film thickness, rather than the more conventional "Spreading Rate" function employed in Test Methods D 344 and D 2805 and other hiding power test methods. Note 2-Hiding power is photometrically defined as the spreading rate at 0.98 contrast ratio. See definitions of spreading rate and hiding power in Terminology D 16, D 2805, and the Paint and Coatings Testing Manual. Note 3-The contrast ratio of 0.98 is conventionally accepted in the coatings industry as representing "complete" hiding for reflectometric hiding power measurements. But visually, as well as photometrically, it is slightly less than complete. 1.2 These test methods cover the determination of the hiding power of powder coatings applied by electrostatic spraying. 1.3 These test methods determine hiding power by means of reflectometric and thickness gage measurements. They are limited to coatings having a minimum CIE-Y reflectance of 15 %. 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 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 and health practices and determine the applicability of regulatory limitations prior to use.