1.1 本规程涵盖了适用于按照规程对塑料进行氙弧暴露的特定程序和试验条件 G151 和 G155 本规程还包括试样的制备、最适合塑料的试验条件以及试验结果的评估。 1.2 以国际单位制表示的数值应视为标准。括号中给出的值是英寸磅单位的数学转换，仅供参考，不被视为标准。 1.3 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。 注1: 本规范和ISO 4892-2涉及相同的主题，但技术内容不同。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ===意义和用途====== 4.1 塑料材料抵抗其电气、机械和光学性能因暴露于光、热和水而退化的能力对于许多应用来说是非常重要的。这种做法旨在引起与最终使用条件相关的性能变化，包括日光、湿度和热量的影响。本规程中使用的暴露不是为了模拟局部天气现象造成的恶化，如大气污染、生物攻击和盐水暴露。 4.2 小心 --当操作条件在本规程的可接受范围内变化时，结果可能会发生变化。因此，所有提及使用本惯例的内容都必须附有根据第节编制的报告 9 其描述了所使用的特定操作条件。参考实践 G151 有关适用于使用根据本惯例获得的结果的注意事项的详细信息。 注2: 关于实验室加速暴露试验的设计、执行和数据分析中变异性来源和应对变异性策略的更多信息，请参阅指南 G141 。 4.3 当根据与其他材料或对照品相比的性能等级来评估材料的稳定性时，实验室之间的测试结果的再现性已被证明是良好的。 6. ， 7. 因此，强烈建议在试验材料的同时暴露具有已知性能的类似材料（对照品）。 优选的是，对照材料的试样数量与用于测试材料的试样的数量相同。建议每种材料至少暴露三次，以便对结果进行统计评估。 4.4 测试结果将取决于根据实践操作设备时所采取的谨慎措施 G155 重要因素包括线路电压的调节、无盐或其他水沉积物、温度和湿度控制以及灯和过滤器的状况和使用年限。

1.1 This practice covers specific procedures and test conditions that are applicable for xenon-arc exposure of plastics conducted in accordance with Practices G151 and G155 . This practice also covers the preparation of test specimens, the test conditions best suited for plastics, and the evaluation of test results. 1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered 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. Note 1: This practice and ISO 4892-2 address the same subject matter, but differ in technical content. 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 ====== 4.1 The ability of a plastic material to resist deterioration of its electrical, mechanical, and optical properties caused by exposure to light, heat, and water can be very significant for many applications. This practice is intended to induce property changes associated with end-use conditions, including the effects of daylight, moisture, and heat. The exposure used in this practice is not intended to simulate the deterioration caused by localized weather phenomena, such as, atmospheric pollution, biological attack, and saltwater exposure. 4.2 Caution —Variations in results are possible when operating conditions are varied within the accepted limits of this practice. Therefore, all references to the use of this practice must be accompanied by a report prepared in accordance with Section 9 that describes the specific operating conditions used. Refer to Practice G151 for detailed information on the caveats applicable to use of results obtained in accordance with this practice. Note 2: Additional information on sources of variability and on strategies for addressing variability in the design, execution, and data analysis of laboratory-accelerated exposure tests is found in Guide G141 . 4.3 Reproducibility of test results between laboratories has been shown to be good when the stability of materials is evaluated in terms of performance ranking compared to other materials or to a control. 6 , 7 Therefore, exposure of a similar material of known performance (a control) at the same time as the test materials is strongly recommended. It is preferable that the number of specimens of the control material be the same as that used for test materials. It is recommended that at least three replicates of each material be exposed to allow for statistical evaluation of results. 4.4 Test results will depend upon the care that is taken to operate the equipment in accordance with Practice G155 . Significant factors include regulation of line voltage, freedom from salts or other deposits from water, temperature and humidity control, and condition and age of the lamp and filters.