1.1 本试验方法使用紫外线、可见光和近红外区域的反射光谱，以产生聚合物壁板在环境温度以上的温升指数，该温升是由于吸收太阳能量而产生的。 1.2 试验方法确定样品颜色的强度因子。强度因子是样品反射光谱和测试方法中使用的热灯能量输出的函数 D4803 . 1.3 附录X1 提供了一种使用强度因子确定严重太阳照射下样品最大温升的方法。 1.3.1 强度因子与试验方法预测的热量累积（温升）之间的相关性 D4803 存在。 1.3.2 聚合物建筑产品样品的蓄热（温升）由其反射光谱和相关回归方程确定。 1.4 单位- 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。 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 聚合物建筑产品因吸收太阳能量而蓄热，可能导致变形问题。试验方法试验方法 D4803 用于预测建筑产品的热量累积（温升）。它比较了着色PVC产品和含有炭黑的PVC面板在暴露于红外加热灯时的相对温度变化。根据在太阳照射和实验室测试中确定该黑色面板最高温度的实验结果，开发了一种确定测试面板外部温升和热量累积的方法。 该测试已证明是有用和可靠的，但耗时，需要受控条件以将变化源降至最低。 5.2 本试验方法使用分光光度计测量样品在紫外线、可见光和近红外区域的反射率，并使用试验方法中规定的加热灯的光谱功率分布 D4803 确定强度因子，强度因子是试样相对光谱能量吸收的指数。 5.2.1 试验方法下可能出现的温升 D4803 测试与该强度因子成比例。根据从试验方法获得的强度因子和温升数据的相关性推导出了一个方程 D4803 测试各种颜色和亮度的样品。共研究了99个样品，代表最低至最高温升的样品。线性回归分析得出R2相关系数为0.98。 5.2.2 中的程序 附录X1 允许预测测试方法下相同样品测试产生的温升 D4803 . 5.2.3 因为该程序与通过试验方法获得的结果相关 D4803 ，该方法在某些规定的恶劣条件下产生与黑色相比的相对温升，但不能预测产品的实际现场应用温度。这些产品温度受太阳入射角、云层、风速、绝缘、玻璃后安装等的影响。 5.3 强度因子本身是试样相对能量吸收的无量纲指数，不转换为温升。 它可用于比较不同颜色的热量累积特性，或相同颜色的不同候选配方。它还可以用于将颜色划分为强度因子范围，作为测试全壁板产品耐热变形性的基础。

1.1 This test method uses reflectance spectra from the ultraviolet, visible, and near infrared region to produce an index of the temperature rise of polymeric siding above ambient temperature that occurs due to absorption of the sun’s energy. 1.2 The test method determines the intensity factor of a sample color. The intensity factor is a function of the sample’s reflectance spectra and the energy output of the heat lamp used in the test method Test Method D4803 . 1.3 Appendix X1 provides a method for using the intensity factor to determine the maximum temperature rise of a sample under severe solar exposure. 1.3.1 A correlation between intensity factor and heat buildup (temperature rise) as predicted by Test Method D4803 exists. 1.3.2 The heat buildup (temperature rise) for a polymeric building product specimen is determined from its reflectance spectra and the correlation’s regression equation. 1.4 Units— 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. 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 Heat buildup of polymeric building products due to absorption of energy from the sun may lead to distortion problems. Test Method Test Method D4803 was developed to predict a building product’s heat buildup (temperature rise). It compares the relative temperature changes of a pigmented PVC product and a PVC panel containing carbon black when exposed to an infrared heat lamp. Based on experimental results that determined the maximum temperature for this black panel under both solar exposure and in the laboratory test, a method for determining the exterior temperature rise and heat buildup for a test panel was developed. This test has shown to be useful and reliable but is time consuming and requires controlled conditions to minimize sources of variation. 5.2 This test method uses a spectrophotometer to measure a specimen’s reflectance in the ultraviolet, visible, and near infrared region and uses the spectral power distribution of the heat lamp specified in Test Method D4803 to determine an intensity factor, which is an index of the relative spectral energy absorption by the specimen. 5.2.1 The temperature rise that would occur under an Test Method D4803 test is proportional to this intensity factor. An equation has been derived from the correlation of the intensity factor and temperature rise data obtained from Test Method D4803 testing of samples with a wide range of color and lightness. A total of 99 samples were studied and represent samples with the lowest to highest temperature rise. Linear regression analysis yields a R2 correlation coefficient of 0.98. 5.2.2 The procedure in Appendix X1 allows prediction of temperature rise that would result from testing of the same sample under Test Method D4803 . 5.2.3 As this procedure is a correlation to results obtained by Test Method D4803 , it is a method that yields a relative temperature rise compared to black under certain defined severe conditions, but does not predict actual field application temperatures of the product. These product temperatures are influenced by incident angle of the sun, clouds, wind speed, insulation, installation behind glass, etc. 5.3 The intensity factor itself is a dimensionless index of the relative energy absorption of the specimen, without conversion to a temperature rise. It can be used to compare the heat buildup characteristics of different colors, or different candidate formulations for the same color. It can also be used to categorize color into ranges of intensity factor, to be used as a basis for testing of full siding products for resistance to thermal distortion.