材料在室外使用时，长期暴露在日光或玻璃过滤后的日光下，因此测定光、热、湿度和其他气候应力对材料颜色和性能的影响非常重要。然而，通常需要采用特定实验室光源加速老化试验来更加快速的测定光、热、湿度对材料物理、化学和光学性能的影响。实验室设备中的暴露比大气老化有更多的可控条件下进行，用来加速高聚物降解和产生失效。试验结果适用于比较材料的有关性能；一种常见的应用是确定不同批次材料的质量水平与已知性能的对照物是否相同。当材料在同一暴露设备中同时试验时，材料间的比较合适。结果可以通过比较材料的特定性能下降到某一特定水平所需的暴露时间或辐照量来表示。
When the material is used at outdoor，exposure under the sunlight or sunlight after glass filtering for a long time，so measuring light，heat，humidity and other climate stress is very important to effect on material color and performance. But usually it need adopt specific lab light source to accelerate aging test to measure the light， heat， humidity effect on material physic，chemical，optical performance more quickly.Exposuring in the lab euipment has more controlable condition to do test than atmosphere aging，it is used to accelerate polymer degradation and make it invalid.Test result is used to compare material performance；one common application is to confirm the quality level of different batch material with known performance goods，ａnd see if it is the same.When the material test at the same exposure equipment at the same time，it is most suitable for different material. the ruslt is shown as comparing the exposure time or irradiation intensity for material specific performance falling to certain level.