意义和目的
4.1 The procedures described in this specification are intended to assist in the evaluation of coating performance on a variety of metal panels, including new or rusted steel.

4.2 由于太阳辐射的差异, 潮湿时间, 温度, 污染物, 和其他因素, the relative durability of paint during outdoor exposure may vary considerably depending on the location of the exposure. 所以, it cannot be assumed that the results of a single exposure at a single location will help determine the relative durability of different locations. Exposure is recommended at multiple sites with different climates that represent a wide range of expected service conditions.

4.2.1 Due to annual climate variability, the results of a single exposure test cannot be used to predict the absolute rate of material degradation. It takes several years of repeated exposure to obtain an “平均的” test result for a given location.

4.2.2 Solar radiation varies greatly with the time of year. This can lead to large differences in apparent degradation rates for many polymers. It is not recommended to compare results for materials exposed for a short period of time (less than one year) unless the materials were exposed at the same location at the same time.

4.3 Meaning and Use of G7 in practice addresses many of the variables that need to be considered in external exposure testing. Guide G141 provides more information on variability in aging tests.

美国材料试验协会D 1014-2018 “金属基材上危险油漆和涂料的户外暴露测试”

范围
1.1 This practice covers the procedures to be followed when exposing external paints and coatings directly to metal surfaces. When the sponsor actual exposure of the aging test is carried out by a separate agency, the specific conditions for testing and controlling the exposure of the specimen should be clearly defined and mutually agreed upon by the parties.

1.2 Experience has shown that the metal used as a test substrate has a significant impact on weathering results. The aim of this practice is to define specific steel and other metal surfaces for testing in order to minimize this source of variability.

1.3 以 SI 单位表示的值应被视为标准. 括号内的数值仅供参考.

1.4 本标准并非旨在解决所有安全问题, 如果有的话, 与其使用相关. 本标准的使用者有责任建立适当的安全机制, 健康和环境实践，并在使用前确定监管限制的适用性.

1.5 本国际标准是根据《关于制定国际标准的原则的决定》中确立的国际公认的标准化原则制定的, 世界贸易组织贸易技术壁垒委员会发布的指南和建议.