1.1 本规程描述了估算水平表面上太阳紫外线总辐照度随空气质量和地理位置变化的方法。 1.2 本实践提供了一个数学模型，用于根据特定位置的全球水平辐照度（GHI）数据计算全球水平紫外线辐照度（GHUV）。 1.3 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。 1.4 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。 1.5 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 暴露在室外的产品主要由于三个压力因素而降解:阳光、温度和湿度。属性变化率是时间和压力源强度的函数。 5.2 虽然本规程中计算的紫外线辐照度与材料无关，但它与暴露在室外的聚合物材料尤其相关，因为紫外线辐射和氧气的联合作用通常是导致其降解的主要因素。因此，估算紫外线辐照度是评估产品使用寿命的重要参数。 5.3 在与降解量的相关性方面，紫外线辐射剂量通常比总太阳辐射剂量或持续时间更重要。可以使用从一个位置到另一个位置的紫外线辐射剂量比较来归一化降解结果。 5.4 与太阳总辐照度数据相比，测量的紫外线辐照度数据较少。 许多监测太阳能资源数据的地点只收集太阳总辐射的数据。这种做法允许用户根据任何站点的总太阳辐照度估算紫外线辐照度。

1.1 This practice describes methods to estimate the total solar ultraviolet irradiance on a horizontal surface as a function of Air Mass and geographic location. 1.2 This practice provides a mathematical model for calculating Global Horizontal Ultraviolet irradiance (GHUV) from Global Horizontal Irradiance (GHI) data for a specific location. 1.3 Units— The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 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. 1.5 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 Products exposed outdoors degrade due to primarily three stress factors: sunlight, temperature and moisture. The rate of property change is a function of time and stressors’ intensity. 5.2 Whereas the UV irradiance calculated in this practice is independent of material, it is especially relevant to polymeric materials exposed outdoors as the combined action of UV radiation and oxygen is often the dominant factor leading to their degradation. Therefore, estimating UV irradiance is an important parameter to assess the service life of products. 5.3 UV radiant dosage is often more important to determine in the correlation with the amount of degradation than total solar radiant dosage or duration of time. The comparison of UV radiant dosage from one location to another may be used to normalize degradation results. 5.4 Measured UV irradiance data are scarce compared to total solar irradiance data. Many locations that monitor solar resource data only collect data for total solar radiation. This practice allows the user to estimate the amount of UV irradiance from the amount of total solar irradiance for any site.