1.1 本试验方法涵盖了当直接应用于刚性隔热层或盖板、结构混凝土、轻质隔热混凝土、石膏、水泥木纤维或木质屋顶板上时，测定新型低坡屋顶膜的抗冲击性。制定该程序的目的是确定当新屋顶膜在组件内应用于其测试基底上时，自由下落的钢球撞击导致的新屋顶膜穿孔或断裂的可能性，从而产生特定的冲击能量。 1.2 本试验方法旨在验证所述产品是否符合规定的抗冲击性能条件。 沥青瓦的测试超出了本测试方法的范围。试验得出的分类为2级和3级。 1.3 以国际单位制或英寸磅单位表示的数值应单独视为标准值。每个系统中规定的值可能不完全相等；因此，每个系统应独立使用。将两个系统的值合并可能导致不符合标准。 1.4 本标准并不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建立适当的安全、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《国际标准、指南和建议制定原则决定》中确立的国际公认标准化原则制定的。 =====意义和用途====== 6.1 该测试方法提供了一种评估新型屋顶膜抵抗特定冲击能量的方法。该方法在首次应用时以及在紫外线辐射和湿气导致的模拟劣化之后评估新的屋顶膜。 6.2 使用2级耐冲击性为11.0±0.3 J[8.1±0.2 ft-lb]，使用3级抗冲击性为19.4±0.4 J[14.3±0.3 ft-lb]。

1.1 This test method covers the determination of impact resistance of new low slope roof membranes when applied directly over rigid insulation or cover board, or structural concrete, lightweight insulating concrete, gypsum, cementitious wood fiber, or wood roof decks. The procedures were developed to determine the potential for puncture or fracture of the new roof membrane resulting from impacts by free-falling steel balls resulting in specific impact energies when the new roof membrane is applied over its tested substrate within an assembly. 1.2 This test method is intended to verify that products as described will meet a specific stated condition of impact resistance performance. Testing of asphalt shingles is beyond the scope of this test method. The tests yield classification identified as Class 2 and Class 3. 1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the 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 ====== 6.1 This test method provides a means of evaluating new roof membranes for resistance to specific impact energies. The method evaluates new roof membranes when first applied and also after simulated deterioration caused by the ultraviolet radiation and moisture. 6.2 Use Class 2 for an impact resistance of 11.0 ± 0.3 J [8.1 ± 0.2 ft-lb] and Class 3 for an impact resistance of 19.4 ± 0.4 J [14.3 ± 0.3 ft-lb].