1.1 这些试验方法确定了用作聚氨酯原料的芳香族异氰酸酯的总氯含量。总氯含量和可水解氯含量之间的差异（见试验方法 第4663页 )是氯苯量的量度， o -二氯苯和存在的其它环取代的氯化产物。这两种方法都适用于各种有机化合物，但所用的样品量不同。（参见 注1 .) 1.2 以国际单位制表示的数值应视为标准。括号中给出的值仅供参考。 1.3 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。 注1: 本标准与ISO相同 26603. 1.4 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====== 5.1 这些测试方法适用于研究或质量控制，以确定芳香族异氰酸酯的总氯含量。 在某些情况下，总氯含量可能与聚氨酯系统的性能相关。

1.1 These test methods determine the total chlorine content of aromatic isocyanates used as polyurethane raw materials. The difference between the total chlorine content and the hydrolyzable chlorine content (see Test Method D4663 ) is a measure of the amount of chlorobenzene, o -dichlorobenzene, and other ring-substituted chlorinated products that are present. Both procedures are applicable to a variety of organic compounds but the amount of sample used is varied. (See Note 1 .) 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 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 standard is identical to ISO 26603. 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 ====== 5.1 These test methods are suitable for use for research or for quality control to determine the total chlorine content of aromatic isocyanates. In some instances total chlorine content may correlate with performance in polyurethane systems.