1.1 本规程涵盖了计算调整系数的程序，该调整系数解释了阻燃处理对胶合板屋顶板弯曲强度的影响。根据本规程计算的调整系数将应用于未处理胶合板的设计值，以确定用作屋顶系统护套的阻燃处理胶合板的设计值。这些方法基于在高温下暴露后进行和未进行处理的材料的匹配弯曲强度测试来确定处理效果。 注1: 该分析侧重于在受控暴露于高温和高湿度的特定条件下，与环境条件平衡后，测试的经处理和未经处理材料的相对性能。 在设计阻燃处理的胶合板屋面板时，还必须考虑未处理胶合板设计中通常考虑的高温、湿度、负载持续时间和其他因素，但不在本规程下制定的处理调整范围内。 1.2 假设该程序将用于使用阻燃化学品制造商推荐的适当施工实践安装的阻燃处理胶合板，其中包括避免暴露于沉淀、直接润湿或常规冷凝。 1.3 该实践使用热负荷曲线，反映在美国大陆各种气候的正常使用条件下遇到的暴露。 选择本实践中使用的热增益、太阳能负荷、屋顶坡度、通风率和其他参数来反映常见的倾斜屋顶设计。本规程适用于坡度为3/12或更陡的屋顶、设计有符合国家实践标准的通风区域和通风位置的屋顶，以及护套底侧暴露于通风空气的设计。这些条件可能不适用于显著不同的设计，因此本惯例可能不适用于此类设计。 1.4 支持本惯例规定的信息和简要讨论见附录中的评注。 ASTM还提供了一个更详细的单独注释。 2. 1.5 本实践中的方法并不是为了解释所有报告的阻燃胶合板过早热降解的情况。 1.6 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 1.7 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。 1.8 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 本规程建立了确定调整系数的程序，该调整系数解释了阻燃处理对胶合板屋面板的隔离影响。这些影响是相对于未处理胶合板的性能确定的。本实践使用来自参考热学的数据- 设计用于模拟普通设计斜屋顶温度的荷载循环，以评估50次迭代的产品。 5.2 本规程适用于使用阻燃化学品制造商推荐的施工规程安装的材料，包括避免暴露于沉淀、直接润湿或常规冷凝。这种做法并不适用于与中所述设计有显著不同的建筑物 1.3 . 5.3 试验方法 D5516 在相当短的时间内，在实验室模拟中造成热致强度损失。实验室使用的环境条件- 被认为与现场发生的化学反应类似的活化化学反应。这一假设是这种做法的基本基础。

1.1 This practice covers procedures for calculating adjustment factors that account for the effects of fire-retardant treatment on bending strength of plywood roof sheathing. The adjustment factors calculated in accordance with this practice are to be applied to design values for untreated plywood in order to determine design values for fire-retardant-treated plywood used as sheathing in roof systems. The methods establish the effect of treatment based upon matched bending strength testing of materials with and without treatment after exposure at elevated temperatures. Note 1: This analysis focuses on the relative performance of treated and untreated materials tested after equilibrating to ambient conditions following a controlled exposure to specified conditions of high temperature and humidity. Elevated temperature, moisture, load duration, and other factors typically accounted for in the design of untreated plywood must also be considered in the design of fire-retardant-treated plywood roof sheathing, but are outside the scope of the treatment adjustments developed under this practice. 1.2 It is assumed that the procedures will be used for fire-retardant-treated plywood installed using appropriate construction practices recommended by the fire retardant chemical manufacturers, which include avoiding exposure to precipitation, direct wetting, or regular condensation. 1.3 This practice uses thermal load profiles reflective of exposures encountered in normal service conditions in a wide variety of continental United States climates. The heat gains, solar loads, roof slopes, ventilation rates, and other parameters used in this practice were chosen to reflect common sloped roof designs. This practice is applicable to roofs of 3 in 12 or steeper slopes, to roofs designed with vent areas and vent locations conforming to national standards of practice, and to designs in which the bottom side of the sheathing is exposed to ventilation air. These conditions may not apply to significantly different designs and therefore this practice may not apply to such designs. 1.4 Information and a brief discussion supporting the provisions of this practice are in the Commentary in the appendix. A large, more detailed, separate Commentary is also available from ASTM. 2 1.5 The methodology in this practice is not meant to account for all reported instances of fire-retardant plywood undergoing premature heat degradation. 1.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.7 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. 1.8 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 This practice establishes the procedure to determine adjustment factors that account for the isolated effects of fire-retardant treatment on plywood roof sheathing. These effects are established relative to performance of untreated plywood. This practice uses data from reference thermal-load cycles designed to simulate temperatures in sloped roofs of common design to evaluate products for 50 iterations. 5.2 This practice applies to material installed using construction practices recommended by the fire retardant chemical manufacturers that include avoiding exposure to precipitation, direct wetting, or regular condensation. This practice is not meant to apply to buildings with significantly different designs than those described in 1.3 . 5.3 Test Method D5516 caused thermally induced strength losses in laboratory simulations within a reasonably short period. The environmental conditions used in the laboratory-activated chemical reactions that are considered to be similar to those occurring in the field. This assumption is the fundamental basis of this practice.